From dfischer at usol.com  Wed Aug  4 15:20:28 2004
From: dfischer at usol.com (Duane Fischer, W8DBF)
Date: Wed Aug  4 15:23:19 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
Message-ID: <200408041920.i74JKsG4006927@smtp.usol.com>


	
Greetings, 	
	
What is the 'real' advantage of a stereo uni-directional reel to reel deck
recording two tracks as opposed to a deck recording two tracks in both
directions?	
	
The obvious is that the two tracks one direction only are twice as wide and
should have greater fidelity and better frequency response with less roll off.
What else?	
	
Assume the tape speed is 7.5 ips.	
	
Thank you. 	
	

From sdaitch at ibb.gov  Wed Aug  4 17:00:48 2004
From: sdaitch at ibb.gov (Sheldon Daitch)
Date: Wed Aug  4 17:03:14 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
References: <200408041920.i74JKsG4006927@smtp.usol.com>
Message-ID: <41114E80.BAB5E6C6@ibb.gov>

Duane,

signal to noise ratio is the main benefit.
Everything else the same, the two track system
should be better by about 3 dB in the noise
ratio.

A secondary benefit is much better cross
talk figures.  In a four track stereo system,
the main problem is cross talk from the 
opposite direction tracks.  In a two track
system, the cross talk would be far less
objectionable, resulting essentially in a 
loss of separation, rather than cross talk
from an unrelated audio source. 

Track width could affect frequency response
somewhat, but not significantly, me thinks.

Sheldon



"Duane Fischer, W8DBF" wrote:
> 
> 
> Greetings,
> 
> What is the 'real' advantage of a stereo uni-directional reel to reel deck
> recording two tracks as opposed to a deck recording two tracks in both
> directions?
> 
> The obvious is that the two tracks one direction only are twice as wide and
> should have greater fidelity and better frequency response with less roll off.
> What else?
> 
> Assume the tape speed is 7.5 ips.
> 
> Thank you.
> 
> 
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
From mckee137 at mindspring.com  Wed Aug  4 17:05:16 2004
From: mckee137 at mindspring.com (Robert    J. McKee)
Date: Wed Aug  4 17:07:41 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
Message-ID: <410-2200483421514790@mindspring.com>

Duane
There should be less noise and fewer dropouts.
Bob McKee



> [Original Message]
> From: Duane Fischer, W8DBF <dfischer@usol.com>
> To: <vintage-audio@mailman.qth.net>
> Date: 8/4/04 3:23:19 PM
> Subject: [Vintage-Audio] 2Track Vs 4 Track
>
>
> 	
> Greetings, 	
> 	
> What is the 'real' advantage of a stereo uni-directional reel to reel deck
> recording two tracks as opposed to a deck recording two tracks in both
> directions?	
> 	
> The obvious is that the two tracks one direction only are twice as wide
and
> should have greater fidelity and better frequency response with less roll
off.
> What else?	
> 	
> Assume the tape speed is 7.5 ips.	
> 	
> Thank you. 	
> 	
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com ** 


From aa6dx at pacbell.net  Wed Aug  4 17:26:18 2004
From: aa6dx at pacbell.net (Mark - AA6DX)
Date: Wed Aug  4 17:28:50 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
References: <200408041920.i74JKsG4006927@smtp.usol.com>
Message-ID: <000d01c47a69$b76c4f60$7562ce3f@main>

Far less cross talk is encountered using half track recording, and there are
no sounds coming in backwards.  Mark


From wolfbob at csnsys.com  Wed Aug  4 18:30:40 2004
From: wolfbob at csnsys.com (wolfbob)
Date: Wed Aug  4 18:33:04 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
References: <200408041920.i74JKsG4006927@smtp.usol.com>
	<41114E80.BAB5E6C6@ibb.gov>
Message-ID: <007401c47a72$acd2e7e0$6600a8c0@bobgk3l43zyuqn>

Cross talk is a non-issue. I have NEVER heard any crosstalk on a properly
aligned 4 track stereo deck. Signal to noise is the main parameter and I
think the number is more like a 4+ dB improvement. Going to 15 ips will give
you better frequency response and better noise especially at the high end as
it has less equalization.

WBob

----- Original Message ----- 
From: "Sheldon Daitch" <sdaitch@ibb.gov>
To: "Vintage home and professional audio equipment from 1975 back"
<vintage-audio@mailman.qth.net>
Sent: Wednesday, August 04, 2004 2:00 PM
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track


> Duane,
>
> signal to noise ratio is the main benefit.
> Everything else the same, the two track system
> should be better by about 3 dB in the noise
> ratio.
>
> A secondary benefit is much better cross
> talk figures.  In a four track stereo system,
> the main problem is cross talk from the
> opposite direction tracks.  In a two track
> system, the cross talk would be far less
> objectionable, resulting essentially in a
> loss of separation, rather than cross talk
> from an unrelated audio source.
>
> Track width could affect frequency response
> somewhat, but not significantly, me thinks.
>
> Sheldon
>
>
>
> "Duane Fischer, W8DBF" wrote:
> >
> >
> > Greetings,
> >
> > What is the 'real' advantage of a stereo uni-directional reel to reel
deck
> > recording two tracks as opposed to a deck recording two tracks in both
> > directions?
> >
> > The obvious is that the two tracks one direction only are twice as wide
and
> > should have greater fidelity and better frequency response with less
roll off.
> > What else?
> >
> > Assume the tape speed is 7.5 ips.
> >
> > Thank you.
> >
> >
> > _______________________________________________
> > Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> > List Administrator: Duane Fischer, W8DBF
> > ** For Assistance: dfischer@usol.com **
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
>
>
>


From mclarson at rcc.com  Wed Aug  4 18:58:32 2004
From: mclarson at rcc.com (Mike Clarson)
Date: Wed Aug  4 18:59:23 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
In-Reply-To: <200408041920.i74JKsG4006927@smtp.usol.com>
Message-ID: <003a01c47a76$91874ef0$86010c0a@clarson>

Many assume "advantages" are sonic. Many are not.

Simpler mechanics

Sells more tape

Tapes play on 4 track machines (Anyone have numbers on how S/N was affected
here?)

Head alignment less critical

Heads last longer

Were available cheap when rest of the world went 4 track

--Mike

-----Original Message-----
From: vintage-audio-bounces@mailman.qth.net
[mailto:vintage-audio-bounces@mailman.qth.net]On Behalf Of Duane
Fischer, W8DBF
Sent: Wednesday, August 04, 2004 3:20 PM
To: vintage-audio@mailman.qth.net
Subject: [Vintage-Audio] 2Track Vs 4 Track




Greetings,

What is the 'real' advantage of a stereo uni-directional reel to reel deck
recording two tracks as opposed to a deck recording two tracks in both
directions?

The obvious is that the two tracks one direction only are twice as wide and
should have greater fidelity and better frequency response with less roll
off.
What else?

Assume the tape speed is 7.5 ips.

Thank you.


From wolfbob at csnsys.com  Wed Aug  4 20:31:39 2004
From: wolfbob at csnsys.com (wolfbob)
Date: Wed Aug  4 20:34:00 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
References: <003a01c47a76$91874ef0$86010c0a@clarson>
Message-ID: <008a01c47a83$93307f30$6600a8c0@bobgk3l43zyuqn>

Somethings wrong here:
----- Original Message ----- 
From: "Mike Clarson" <mclarson@rcc.com>
To: "'Vintage home and professional audio equipment from 1975 back'"
<vintage-audio@mailman.qth.net>
Sent: Wednesday, August 04, 2004 3:58 PM
Subject: RE: [Vintage-Audio] 2Track Vs 4 Track


> Many assume "advantages" are sonic. Many are not.
>
> Simpler mechanics

Where??? same everything mechanical

>
> Sells more tape

Very true..also requires rewinding before play (should be stored tails out)

>
> Tapes play on 4 track machines (Anyone have numbers on how S/N was
affected
> here?)

By about 4-5 dB

>
> Head alignment less critical

True but not really. You should have about the same criticality to get the
best out of the deck.

>
> Heads last longer

No...exactly the same.

>
> Were available cheap when rest of the world went 4 track

Not really as those early 2 track decks weren't worth much copmpared to the
"professional" ones to come later and even today.
WBob


>


From aa6dx at pacbell.net  Wed Aug  4 22:15:23 2004
From: aa6dx at pacbell.net (Mark - AA6DX)
Date: Wed Aug  4 22:18:12 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
Message-ID: <00ae01c47a92$23e6aaf0$7562ce3f@main>

Cross talk is indeed an issue.  One may never hear crosstalk on a properly
aligned 4 track, but, if you purchase pre- recorded tapes, or the product
comes from a different recorder, you may well have your recording invaded by
other way sound.  Industry standard test tapes are designed to eliminate
this problem, but a lot of audiophiles never bothered, because the tapes
played back swell on their own machine.  Signal to noise is very
important... but so is equalization and head room.  As an aside, most home
users did not set their equalization to match their chosen brand and
specific blank tape, and lost much of the quality they hoped to gain by the
expenditure for the "high priced spread".

Why do you suppose the broadcast industry universally uses half track?
Surely not so they can spend more money on tape!  If your local radio
station gets its ads (hopefully for your favorite presidential candidate)
via ancient reel to reel tape, it will be half track.

15 IPS and half track was (or is, I don't know) the professional standard
for high fidelity stereo content using 1/4" tape.  One inch tape if you were
serious, and could afford the hardware.

I spent 10 years in the sales part of audio, and 10 years in Broadcast, and
throw in a few years in the advertising agency business.  But there are
those who know more than I.

Far West Mark



From dfischer at usol.com  Wed Aug  4 23:02:58 2004
From: dfischer at usol.com (Duane Fischer, W8DBF)
Date: Wed Aug  4 23:14:59 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
Message-ID: <200408050312.i753CaG4011985@smtp.usol.com>

Mark and All, 	
	
I certainly do not remember any user controlled equalization control on the reel
to reel decks I owned during the sixties and first several years of the
seventies. I do remember them in the middle seventies though. I used Sony, Voice
Of Music, Grundig and Teac.	
	
My Revox B77 from 1980 has it, as does the Teac A-5500 from circa 1975. 		
	
The only time I ever experienced any crosstalk was when I recorded on tapes
longer than 1800 feet. Hence, I stopped using them. I always purchased a better
quality tape and this appeared to minimize any recording or playback issues. I
also made sure that the machines were properly maintained, cleaned and used on a
regular basis. They did not like being allowed to sit idle for too long!  	
	
Does anyone know when equalization controls became standard on home consumer
stereo equipment?	
	
Duane W8DBF	

	
The only time I ever experienced any crosstalk was when the recording tape was
longer than 1800 feet. The more thin the tape was, 

----------
From: Mark - AA6DX <aa6dx@pacbell.net>
To: Vintage home and professional audio equipment from 1975 back
<vintage-audio@mailman.qth.net>
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
Date: Wednesday, August 04, 2004 10:15 PM

Cross talk is indeed an issue.  One may never hear crosstalk on a properly
aligned 4 track, but, if you purchase pre- recorded tapes, or the product
comes from a different recorder, you may well have your recording invaded by
other way sound.  Industry standard test tapes are designed to eliminate
this problem, but a lot of audiophiles never bothered, because the tapes
played back swell on their own machine.  Signal to noise is very
important... but so is equalization and head room.  As an aside, most home
users did not set their equalization to match their chosen brand and
specific blank tape, and lost much of the quality they hoped to gain by the
expenditure for the "high priced spread".

Why do you suppose the broadcast industry universally uses half track?
Surely not so they can spend more money on tape!  If your local radio
station gets its ads (hopefully for your favorite presidential candidate)
via ancient reel to reel tape, it will be half track.

15 IPS and half track was (or is, I don't know) the professional standard
for high fidelity stereo content using 1/4" tape.  One inch tape if you were
serious, and could afford the hardware.

I spent 10 years in the sales part of audio, and 10 years in Broadcast, and
throw in a few years in the advertising agency business.  But there are
those who know more than I.

Far West Mark



_______________________________________________
Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer@usol.com ** 
From wolfbob at csnsys.com  Wed Aug  4 23:30:49 2004
From: wolfbob at csnsys.com (wolfbob)
Date: Wed Aug  4 23:33:06 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
References: <00ae01c47a92$23e6aaf0$7562ce3f@main>
Message-ID: <00b401c47a9c$9ae285c0$6600a8c0@bobgk3l43zyuqn>

No sorry but wrong again. All the test tapes I have (about 12) all are full
track and are not ever used to align the heads in any dinmension that would
influence crosstalk. That is done by mechanical alignment of the tape edges
and the head gaps. Test tapes are used for setting levels, aligning azimuth
and correcting equalization, not for setting where the tape goes by the
heads. Again after aligning, testing and using about three different 1/4
inch 4 track reel to reel decks per week for the last five years, that I
have never heard ANY crosstalk on an aligned deck either with it's own or
other decks tape or with prerecorded tapes (which I have about 100). You
possibly are mistaking print through for crosstalk.

If you think the gap spacing is tight in 1/4 inch 4 track, it is the same as
1/2 inch 8 track and 1 inch 16 track, the very popular standards for the
recording industry. Carrying it to an extreme look at the cassette where you
have 4 tracks in 1/8 inch or so. Yet the cassette is not driven by the
appearance of any crosstalk.

Now it was a problem in the decks made in the early 40s before they figured
out how to get some shielding between the gaps, but all of the Japanese,
most of the US and all but some early European decks have never had this
problem. Certainly any 4 track stereo deck used adequate shielding and
therefore no crosstalk as they were all built after about 1950.

WBob


----- Original Message ----- 
From: "Mark - AA6DX" <aa6dx@pacbell.net>
To: "Vintage home and professional audio equipment from 1975 back"
<vintage-audio@mailman.qth.net>
Sent: Wednesday, August 04, 2004 7:15 PM
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track


> Cross talk is indeed an issue.  One may never hear crosstalk on a properly
> aligned 4 track, but, if you purchase pre- recorded tapes, or the product
> comes from a different recorder, you may well have your recording invaded
by
> other way sound.  Industry standard test tapes are designed to eliminate
> this problem, but a lot of audiophiles never bothered, because the tapes
> played back swell on their own machine.  Signal to noise is very
> important... but so is equalization and head room.  As an aside, most home
> users did not set their equalization to match their chosen brand and
> specific blank tape, and lost much of the quality they hoped to gain by
the
> expenditure for the "high priced spread".
>
> Why do you suppose the broadcast industry universally uses half track?
> Surely not so they can spend more money on tape!  If your local radio
> station gets its ads (hopefully for your favorite presidential candidate)
> via ancient reel to reel tape, it will be half track.
>
> 15 IPS and half track was (or is, I don't know) the professional standard
> for high fidelity stereo content using 1/4" tape.  One inch tape if you
were
> serious, and could afford the hardware.
>
> I spent 10 years in the sales part of audio, and 10 years in Broadcast,
and
> throw in a few years in the advertising agency business.  But there are
> those who know more than I.
>
> Far West Mark
>
>
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
>
>
>


From dfischer at usol.com  Thu Aug  5 00:08:04 2004
From: dfischer at usol.com (Duane Fischer, W8DBF)
Date: Thu Aug  5 00:10:43 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
Message-ID: <200408050408.i7548LG4012337@smtp.usol.com>

Bob, 	
	
How does the calibration tape work for the Teac AN-180 external Dolby and
equalization unit? It is my understanding that once it is calibrated, the tape
is not needed again. True or myth? 		
	
Duane W8DBF	

	
 
----------
From: wolfbob <wolfbob@csnsys.com>
To: Mark - AA6DX <aa6dx@pacbell.net>; Vintage home and professional audio
equipment from 1975 back <vintage-audio@mailman.qth.net>
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
Date: Wednesday, August 04, 2004 11:30 PM

No sorry but wrong again. All the test tapes I have (about 12) all are full
track and are not ever used to align the heads in any dinmension that would
influence crosstalk. That is done by mechanical alignment of the tape edges
and the head gaps. Test tapes are used for setting levels, aligning azimuth
and correcting equalization, not for setting where the tape goes by the
heads. Again after aligning, testing and using about three different 1/4
inch 4 track reel to reel decks per week for the last five years, that I
have never heard ANY crosstalk on an aligned deck either with it's own or
other decks tape or with prerecorded tapes (which I have about 100). You
possibly are mistaking print through for crosstalk.

If you think the gap spacing is tight in 1/4 inch 4 track, it is the same as
1/2 inch 8 track and 1 inch 16 track, the very popular standards for the
recording industry. Carrying it to an extreme look at the cassette where you
have 4 tracks in 1/8 inch or so. Yet the cassette is not driven by the
appearance of any crosstalk.

Now it was a problem in the decks made in the early 40s before they figured
out how to get some shielding between the gaps, but all of the Japanese,
most of the US and all but some early European decks have never had this
problem. Certainly any 4 track stereo deck used adequate shielding and
therefore no crosstalk as they were all built after about 1950.

WBob


----- Original Message ----- 
From: "Mark - AA6DX" <aa6dx@pacbell.net>
To: "Vintage home and professional audio equipment from 1975 back"
<vintage-audio@mailman.qth.net>
Sent: Wednesday, August 04, 2004 7:15 PM
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track


> Cross talk is indeed an issue.  One may never hear crosstalk on a properly
> aligned 4 track, but, if you purchase pre- recorded tapes, or the product
> comes from a different recorder, you may well have your recording invaded
by
> other way sound.  Industry standard test tapes are designed to eliminate
> this problem, but a lot of audiophiles never bothered, because the tapes
> played back swell on their own machine.  Signal to noise is very
> important... but so is equalization and head room.  As an aside, most home
> users did not set their equalization to match their chosen brand and
> specific blank tape, and lost much of the quality they hoped to gain by
the
> expenditure for the "high priced spread".
>
> Why do you suppose the broadcast industry universally uses half track?
> Surely not so they can spend more money on tape!  If your local radio
> station gets its ads (hopefully for your favorite presidential candidate)
> via ancient reel to reel tape, it will be half track.
>
> 15 IPS and half track was (or is, I don't know) the professional standard
> for high fidelity stereo content using 1/4" tape.  One inch tape if you
were
> serious, and could afford the hardware.
>
> I spent 10 years in the sales part of audio, and 10 years in Broadcast,
and
> throw in a few years in the advertising agency business.  But there are
> those who know more than I.
>
> Far West Mark
>
>
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
>
>
>


_______________________________________________
Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer@usol.com ** 
From wolfbob at csnsys.com  Thu Aug  5 01:58:30 2004
From: wolfbob at csnsys.com (wolfbob)
Date: Thu Aug  5 02:00:48 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
References: <200408050408.i7548LG4012337@smtp.usol.com>
Message-ID: <00d201c47ab1$3c602330$6600a8c0@bobgk3l43zyuqn>

True, if nothing changes. The tape is an easy one to get. Someone with a
calibrated deck can make you a tape at 185nWb/m fluxivity and I believe 700
Hz. This is dB or the reference level for Dolby systems. dbx systems use
1000 Hz at 185 nWb/m. The frequency is the crossover point for the
compression and needs to be correct.

WBob

----- Original Message ----- 
From: "Duane Fischer, W8DBF" <dfischer@usol.com>
To: "Vintage home and professional audio equipment from 1975 back"
<vintage-audio@mailman.qth.net>
Sent: Wednesday, August 04, 2004 9:08 PM
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track


> Bob,
>
> How does the calibration tape work for the Teac AN-180 external Dolby and
> equalization unit? It is my understanding that once it is calibrated, the
tape
> is not needed again. True or myth?
>
> Duane W8DBF
>
>
>
> ----------
> From: wolfbob <wolfbob@csnsys.com>
> To: Mark - AA6DX <aa6dx@pacbell.net>; Vintage home and professional audio
> equipment from 1975 back <vintage-audio@mailman.qth.net>
> Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
> Date: Wednesday, August 04, 2004 11:30 PM
>
> No sorry but wrong again. All the test tapes I have (about 12) all are
full
> track and are not ever used to align the heads in any dinmension that
would
> influence crosstalk. That is done by mechanical alignment of the tape
edges
> and the head gaps. Test tapes are used for setting levels, aligning
azimuth
> and correcting equalization, not for setting where the tape goes by the
> heads. Again after aligning, testing and using about three different 1/4
> inch 4 track reel to reel decks per week for the last five years, that I
> have never heard ANY crosstalk on an aligned deck either with it's own or
> other decks tape or with prerecorded tapes (which I have about 100). You
> possibly are mistaking print through for crosstalk.
>
> If you think the gap spacing is tight in 1/4 inch 4 track, it is the same
as
> 1/2 inch 8 track and 1 inch 16 track, the very popular standards for the
> recording industry. Carrying it to an extreme look at the cassette where
you
> have 4 tracks in 1/8 inch or so. Yet the cassette is not driven by the
> appearance of any crosstalk.
>
> Now it was a problem in the decks made in the early 40s before they
figured
> out how to get some shielding between the gaps, but all of the Japanese,
> most of the US and all but some early European decks have never had this
> problem. Certainly any 4 track stereo deck used adequate shielding and
> therefore no crosstalk as they were all built after about 1950.
>
> WBob
>
>
> ----- Original Message ----- 
> From: "Mark - AA6DX" <aa6dx@pacbell.net>
> To: "Vintage home and professional audio equipment from 1975 back"
> <vintage-audio@mailman.qth.net>
> Sent: Wednesday, August 04, 2004 7:15 PM
> Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
>
>
> > Cross talk is indeed an issue.  One may never hear crosstalk on a
properly
> > aligned 4 track, but, if you purchase pre- recorded tapes, or the
product
> > comes from a different recorder, you may well have your recording
invaded
> by
> > other way sound.  Industry standard test tapes are designed to eliminate
> > this problem, but a lot of audiophiles never bothered, because the tapes
> > played back swell on their own machine.  Signal to noise is very
> > important... but so is equalization and head room.  As an aside, most
home
> > users did not set their equalization to match their chosen brand and
> > specific blank tape, and lost much of the quality they hoped to gain by
> the
> > expenditure for the "high priced spread".
> >
> > Why do you suppose the broadcast industry universally uses half track?
> > Surely not so they can spend more money on tape!  If your local radio
> > station gets its ads (hopefully for your favorite presidential
candidate)
> > via ancient reel to reel tape, it will be half track.
> >
> > 15 IPS and half track was (or is, I don't know) the professional
standard
> > for high fidelity stereo content using 1/4" tape.  One inch tape if you
> were
> > serious, and could afford the hardware.
> >
> > I spent 10 years in the sales part of audio, and 10 years in Broadcast,
> and
> > throw in a few years in the advertising agency business.  But there are
> > those who know more than I.
> >
> > Far West Mark
> >
> >
> >
> > _______________________________________________
> > Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> > List Administrator: Duane Fischer, W8DBF
> > ** For Assistance: dfischer@usol.com **
> >
> >
> >
>
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
>
>
>


From mckee137 at mindspring.com  Thu Aug  5 05:47:35 2004
From: mckee137 at mindspring.com (Robert    J. McKee)
Date: Thu Aug  5 05:49:56 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
Message-ID: <410-2200484594735260@mindspring.com>

"As an aside, most home users did not set their equalization to
match their chosen brand and specific blank tape, and lost much
of the quality they hoped to gain by the expenditure for the "high
priced spread."".

I believe one will find that equalization does not change from
tape to tape.  What does require changing is the bias level.
This of course is on the record side of the process.  The 
playback equalization is the same for all formulations of 
tape at a given speed.  Only EE tape uses a different EQ
on playback.  WBob will need to confirm that point but
I believe it is correct.

Playback head wear and subsequent relapping will most
times cause a need for playback reequalization.  This
should not be an issue on glass head machines.

Bob McKee
using only Crown reel to reel equipment


From dfischer at usol.com  Thu Aug  5 07:58:41 2004
From: dfischer at usol.com (Duane Fischer, W8DBF)
Date: Thu Aug  5 08:01:34 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
Message-ID: <200408051158.i75BwvG4014534@smtp.usol.com>

Bob, 	
	
I just happen to have the original tape and a copy of the manual. I got this
from a Ham friend on the west side of Michigan who saw it in a local shop. He
got it for a very small price. Because he is an excellent technician, he checked
it out prior to buying it. Other than some dirt, it looked new.	
	
he got it home and opened it up. Inside it looked like new. He doubted it had
ever been used, and if so, very very little. He cleaned all controls and the
front panel up, it looks like it just came out of the original box in the
seventies. 			
	
I did some checking and learned that the Teac AN-180 sold new for $350, no
inexpensive item for the seventies! 	
	
My cousin, Mr. If It Isn't Classical Or Opera, It Is Not Music, has the AN-60
for his Revox B77. (This Revox had no Dolby for those are wondering.) It looks
like a little toy compared to this complex machine with knobs, switches, meters,
jacks and so forth.	
	
It was tested and passed perfectly. Fully functional with all components within
tolerances.	
	
I do not truly understand what I am about to say, so know that at the outset! 	
	
I have heard that once upon a time commercial FM stations broadcast in a format
that required, or could use, a product like the Teac AN-180 to equalize the
incoming signal. This practice was shortlived though and was quickly dropped.
What was this all about? I know it was supposed to improve the frequency and/or
quality of the broadcast signal. Did it and if so, why was it dropped, and so
quickly? Simply not practical? More hype than fact? Cost too much for the
obvious improvement to temtp the consumers, as in passing fad? 		
	
It appears that one can add Dolby to anything you can plug into this item. 	
	
Duane W8DBF	

	



----------
From: wolfbob <wolfbob@csnsys.com>
To: Vintage home and professional audio equipment from 1975 back
<vintage-audio@mailman.qth.net>
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
Date: Thursday, August 05, 2004 1:58 AM

True, if nothing changes. The tape is an easy one to get. Someone with a
calibrated deck can make you a tape at 185nWb/m fluxivity and I believe 700
Hz. This is dB or the reference level for Dolby systems. dbx systems use
1000 Hz at 185 nWb/m. The frequency is the crossover point for the
compression and needs to be correct.

WBob

----- Original Message ----- 
From: "Duane Fischer, W8DBF" <dfischer@usol.com>
To: "Vintage home and professional audio equipment from 1975 back"
<vintage-audio@mailman.qth.net>
Sent: Wednesday, August 04, 2004 9:08 PM
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track


> Bob,
>
> How does the calibration tape work for the Teac AN-180 external Dolby and
> equalization unit? It is my understanding that once it is calibrated, the
tape
> is not needed again. True or myth?
>
> Duane W8DBF
>
>
>
> ----------
> From: wolfbob <wolfbob@csnsys.com>
> To: Mark - AA6DX <aa6dx@pacbell.net>; Vintage home and professional audio
> equipment from 1975 back <vintage-audio@mailman.qth.net>
> Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
> Date: Wednesday, August 04, 2004 11:30 PM
>
> No sorry but wrong again. All the test tapes I have (about 12) all are
full
> track and are not ever used to align the heads in any dinmension that
would
> influence crosstalk. That is done by mechanical alignment of the tape
edges
> and the head gaps. Test tapes are used for setting levels, aligning
azimuth
> and correcting equalization, not for setting where the tape goes by the
> heads. Again after aligning, testing and using about three different 1/4
> inch 4 track reel to reel decks per week for the last five years, that I
> have never heard ANY crosstalk on an aligned deck either with it's own or
> other decks tape or with prerecorded tapes (which I have about 100). You
> possibly are mistaking print through for crosstalk.
>
> If you think the gap spacing is tight in 1/4 inch 4 track, it is the same
as
> 1/2 inch 8 track and 1 inch 16 track, the very popular standards for the
> recording industry. Carrying it to an extreme look at the cassette where
you
> have 4 tracks in 1/8 inch or so. Yet the cassette is not driven by the
> appearance of any crosstalk.
>
> Now it was a problem in the decks made in the early 40s before they
figured
> out how to get some shielding between the gaps, but all of the Japanese,
> most of the US and all but some early European decks have never had this
> problem. Certainly any 4 track stereo deck used adequate shielding and
> therefore no crosstalk as they were all built after about 1950.
>
> WBob
>
>
> ----- Original Message ----- 
> From: "Mark - AA6DX" <aa6dx@pacbell.net>
> To: "Vintage home and professional audio equipment from 1975 back"
> <vintage-audio@mailman.qth.net>
> Sent: Wednesday, August 04, 2004 7:15 PM
> Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
>
>
> > Cross talk is indeed an issue.  One may never hear crosstalk on a
properly
> > aligned 4 track, but, if you purchase pre- recorded tapes, or the
product
> > comes from a different recorder, you may well have your recording
invaded
> by
> > other way sound.  Industry standard test tapes are designed to eliminate
> > this problem, but a lot of audiophiles never bothered, because the tapes
> > played back swell on their own machine.  Signal to noise is very
> > important... but so is equalization and head room.  As an aside, most
home
> > users did not set their equalization to match their chosen brand and
> > specific blank tape, and lost much of the quality they hoped to gain by
> the
> > expenditure for the "high priced spread".
> >
> > Why do you suppose the broadcast industry universally uses half track?
> > Surely not so they can spend more money on tape!  If your local radio
> > station gets its ads (hopefully for your favorite presidential
candidate)
> > via ancient reel to reel tape, it will be half track.
> >
> > 15 IPS and half track was (or is, I don't know) the professional
standard
> > for high fidelity stereo content using 1/4" tape.  One inch tape if you
> were
> > serious, and could afford the hardware.
> >
> > I spent 10 years in the sales part of audio, and 10 years in Broadcast,
> and
> > throw in a few years in the advertising agency business.  But there are
> > those who know more than I.
> >
> > Far West Mark
> >
> >
> >
> > _______________________________________________
> > Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> > List Administrator: Duane Fischer, W8DBF
> > ** For Assistance: dfischer@usol.com **
> >
> >
> >
>
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
>
>
>


_______________________________________________
Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer@usol.com ** 
From wolfbob at csnsys.com  Thu Aug  5 10:54:48 2004
From: wolfbob at csnsys.com (wolfbob)
Date: Thu Aug  5 10:57:15 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
References: <410-2200484594735260@mindspring.com>
Message-ID: <000901c47afc$27d5b240$6600a8c0@bobgk3l43zyuqn>

Playback eq is independent of tape. Record eq and bias are dependent. That
being said, there is very little change in record performance if you use the
"wrong" bias/eq. In most cases you will not achieve the best that the
specific tape can produce, but the resulting recording will be entirely
useable. This is particularily true in using some of the newer tapes such as
GP9 or 499 where the capability of the tape is astounding when properly set
up, but more like olden tapes if not.

True in the reel to reel world that the playback eq changes for tape speed
and for EE tape.In the cassette world there are about four different
playback eqs for various tape types.

WBob

----- Original Message ----- 
From: "Robert J. McKee" <mckee137@mindspring.com>
To: "Vintage home and professional audio equipment from 1975 back"
<vintage-audio@mailman.qth.net>
Sent: Thursday, August 05, 2004 2:47 AM
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track


> "As an aside, most home users did not set their equalization to
> match their chosen brand and specific blank tape, and lost much
> of the quality they hoped to gain by the expenditure for the "high
> priced spread."".
>
> I believe one will find that equalization does not change from
> tape to tape.  What does require changing is the bias level.
> This of course is on the record side of the process.  The
> playback equalization is the same for all formulations of
> tape at a given speed.  Only EE tape uses a different EQ
> on playback.  WBob will need to confirm that point but
> I believe it is correct.
>
> Playback head wear and subsequent relapping will most
> times cause a need for playback reequalization.  This
> should not be an issue on glass head machines.
>
> Bob McKee
> using only Crown reel to reel equipment
>
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
>
>
>


From wolfbob at csnsys.com  Thu Aug  5 11:17:23 2004
From: wolfbob at csnsys.com (wolfbob)
Date: Thu Aug  5 11:19:47 2004
Subject: [Vintage-Audio] 2Track Vs 4 Track
References: <200408051158.i75BwvG4014534@smtp.usol.com>
Message-ID: <001101c47aff$4fd75de0$6600a8c0@bobgk3l43zyuqn>

The broadcast folk have tried a lot of things over the years but now they
just mash everything to 10 dB dynamic range and send it out as loud as they
legally can.

Realize that all Dolby and dbx are recording processors. They are for
improving the dynamic range and frequency response of the tape recording
process. The are not processors to be added to already recorded  material.
What I am trying to say is that to use Dolby or dbx the material has to have
been recorded using the matching Dolby or dbx. There are several (like 6)
different kinds of Dolby and two different kinds of dbx and these too have
to be matched between record and playback. Don't invoke these processors on
ordinary non-processed recordings. they will sound very tinny and in general
bad.

Now something you can add to anything, particularly modern CDs and any FM
broadcast is than expander. I have a dbx 3BX III that adds back in some
dynamic range and makes most music much more delightful. It also has enough
leds to keep one happy just staring at it. Another toy that helps a lot is
the subharmonic generator. This takes the very lowest bass material and
synthesizes matching energy an octave lower. Makes the bass in most music
very clean and whole. I have the dbx 120. Note that these units are made by
dbx but are not dbx compressor/expanders in the dynamic noise reduction
(DNR) sense like your AN-180 or the AN-60. dbx does make several DNR units
both type I and type II which are incompatable with each other.

I think it interesting that the audio processors made 20-30 years ago are
now manditory for listening to CD and FM music. The equivalent of these
units are not being made today. The recording industry has ruined good
recorded music with their processing for use in boom boxes and autos with
the addition? of  massive compression. Good music has been reduced to the
lowest common denominator.

WBob


----- Original Message ----- 
From: "Duane Fischer, W8DBF" <dfischer@usol.com>
To: "Vintage home and professional audio equipment from 1975 back"
<vintage-audio@mailman.qth.net>
Sent: Thursday, August 05, 2004 4:58 AM
Subject: Re: [Vintage-Audio] 2Track Vs 4 Track


> Bob,
>
> I just happen to have the original tape and a copy of the manual. I got
this
> from a Ham friend on the west side of Michigan who saw it in a local shop.
He
> got it for a very small price. Because he is an excellent technician, he
checked
> it out prior to buying it. Other than some dirt, it looked new.
>
> he got it home and opened it up. Inside it looked like new. He doubted it
had
> ever been used, and if so, very very little. He cleaned all controls and
the
> front panel up, it looks like it just came out of the original box in the
> seventies.
>
> I did some checking and learned that the Teac AN-180 sold new for $350, no
> inexpensive item for the seventies!
>
> My cousin, Mr. If It Isn't Classical Or Opera, It Is Not Music, has the
AN-60
> for his Revox B77. (This Revox had no Dolby for those are wondering.) It
looks
> like a little toy compared to this complex machine with knobs, switches,
meters,
> jacks and so forth.
>
> It was tested and passed perfectly. Fully functional with all components
within
> tolerances.
>
> I do not truly understand what I am about to say, so know that at the
outset!
>
> I have heard that once upon a time commercial FM stations broadcast in a
format
> that required, or could use, a product like the Teac AN-180 to equalize
the
> incoming signal. This practice was shortlived though and was quickly
dropped.
> What was this all about? I know it was supposed to improve the frequency
and/or
> quality of the broadcast signal. Did it and if so, why was it dropped, and
so
> quickly? Simply not practical? More hype than fact? Cost too much for the
> obvious improvement to temtp the consumers, as in passing fad?
>
> It appears that one can add Dolby to anything you can plug into this item.
>
> Duane W8DBF
>
>
>
>
>
> ----------
> From: wolfbob <wolfbob@csnsys.com>
> To: Vintage home and professional audio equipment from 1975 back
> <vintage-audio@mailman.qth.net>
> Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
> Date: Thursday, August 05, 2004 1:58 AM
>
> True, if nothing changes. The tape is an easy one to get. Someone with a
> calibrated deck can make you a tape at 185nWb/m fluxivity and I believe
700
> Hz. This is dB or the reference level for Dolby systems. dbx systems use
> 1000 Hz at 185 nWb/m. The frequency is the crossover point for the
> compression and needs to be correct.
>
> WBob
>
> ----- Original Message ----- 
> From: "Duane Fischer, W8DBF" <dfischer@usol.com>
> To: "Vintage home and professional audio equipment from 1975 back"
> <vintage-audio@mailman.qth.net>
> Sent: Wednesday, August 04, 2004 9:08 PM
> Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
>
>
> > Bob,
> >
> > How does the calibration tape work for the Teac AN-180 external Dolby
and
> > equalization unit? It is my understanding that once it is calibrated,
the
> tape
> > is not needed again. True or myth?
> >
> > Duane W8DBF
> >
> >
> >
> > ----------
> > From: wolfbob <wolfbob@csnsys.com>
> > To: Mark - AA6DX <aa6dx@pacbell.net>; Vintage home and professional
audio
> > equipment from 1975 back <vintage-audio@mailman.qth.net>
> > Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
> > Date: Wednesday, August 04, 2004 11:30 PM
> >
> > No sorry but wrong again. All the test tapes I have (about 12) all are
> full
> > track and are not ever used to align the heads in any dinmension that
> would
> > influence crosstalk. That is done by mechanical alignment of the tape
> edges
> > and the head gaps. Test tapes are used for setting levels, aligning
> azimuth
> > and correcting equalization, not for setting where the tape goes by the
> > heads. Again after aligning, testing and using about three different 1/4
> > inch 4 track reel to reel decks per week for the last five years, that I
> > have never heard ANY crosstalk on an aligned deck either with it's own
or
> > other decks tape or with prerecorded tapes (which I have about 100). You
> > possibly are mistaking print through for crosstalk.
> >
> > If you think the gap spacing is tight in 1/4 inch 4 track, it is the
same
> as
> > 1/2 inch 8 track and 1 inch 16 track, the very popular standards for the
> > recording industry. Carrying it to an extreme look at the cassette where
> you
> > have 4 tracks in 1/8 inch or so. Yet the cassette is not driven by the
> > appearance of any crosstalk.
> >
> > Now it was a problem in the decks made in the early 40s before they
> figured
> > out how to get some shielding between the gaps, but all of the Japanese,
> > most of the US and all but some early European decks have never had this
> > problem. Certainly any 4 track stereo deck used adequate shielding and
> > therefore no crosstalk as they were all built after about 1950.
> >
> > WBob
> >
> >
> > ----- Original Message ----- 
> > From: "Mark - AA6DX" <aa6dx@pacbell.net>
> > To: "Vintage home and professional audio equipment from 1975 back"
> > <vintage-audio@mailman.qth.net>
> > Sent: Wednesday, August 04, 2004 7:15 PM
> > Subject: Re: [Vintage-Audio] 2Track Vs 4 Track
> >
> >
> > > Cross talk is indeed an issue.  One may never hear crosstalk on a
> properly
> > > aligned 4 track, but, if you purchase pre- recorded tapes, or the
> product
> > > comes from a different recorder, you may well have your recording
> invaded
> > by
> > > other way sound.  Industry standard test tapes are designed to
eliminate
> > > this problem, but a lot of audiophiles never bothered, because the
tapes
> > > played back swell on their own machine.  Signal to noise is very
> > > important... but so is equalization and head room.  As an aside, most
> home
> > > users did not set their equalization to match their chosen brand and
> > > specific blank tape, and lost much of the quality they hoped to gain
by
> > the
> > > expenditure for the "high priced spread".
> > >
> > > Why do you suppose the broadcast industry universally uses half track?
> > > Surely not so they can spend more money on tape!  If your local radio
> > > station gets its ads (hopefully for your favorite presidential
> candidate)
> > > via ancient reel to reel tape, it will be half track.
> > >
> > > 15 IPS and half track was (or is, I don't know) the professional
> standard
> > > for high fidelity stereo content using 1/4" tape.  One inch tape if
you
> > were
> > > serious, and could afford the hardware.
> > >
> > > I spent 10 years in the sales part of audio, and 10 years in
Broadcast,
> > and
> > > throw in a few years in the advertising agency business.  But there
are
> > > those who know more than I.
> > >
> > > Far West Mark
> > >
> > >
> > >
> > > _______________________________________________
> > > Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> > > List Administrator: Duane Fischer, W8DBF
> > > ** For Assistance: dfischer@usol.com **
> > >
> > >
> > >
> >
> >
> > _______________________________________________
> > Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> > List Administrator: Duane Fischer, W8DBF
> > ** For Assistance: dfischer@usol.com **
> > _______________________________________________
> > Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> > List Administrator: Duane Fischer, W8DBF
> > ** For Assistance: dfischer@usol.com **
> >
> >
> >
>
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
>
>


From aa6dx at pacbell.net  Thu Aug  5 13:26:25 2004
From: aa6dx at pacbell.net (Mark - AA6DX)
Date: Thu Aug  5 13:29:29 2004
Subject: [Vintage-Audio] Reel to Reel Info
Message-ID: <009701c47b11$647116d0$7562ce3f@main>

Howdy Y'all
http://home.flash.net/~mrltapes/
This site, which has the data from the Magnetic Reference Library, has quite
in depth information on the reel to reel recorder alignment, and set up.
Many items are presented in Portable Document Format (PDF), so it is advised
to have Adobe Acrobat Reader, or its equivalent, on your computer.   Be
prepared to spend some time, as it well written and documented, making for a
good read!  I have not tuned up a tape recorder since about 1983, so I
enjoyed getting a refresher course!  I remember the automated radio stations
that ran banks of reel tapes, and would like to know how many heads I have
lapped!   Used a plate of glass, varying degrees of emery paper, and then
polished with a jeweler's rouge cloth.
As to crosstalk (unwanted signal leakage from one signal path to another), I
was often replacing headblocks, and so forth, and had to adjust the az and
zenith, the wrap, etc ..  and the positioning of the tape came as part of
the game, but I don't disagree with WBob and all.  We used to get a lot of
poorly recorded ad spots from hither and yon, many small, and I mean small,
market stations used home quality stereo machines, which the jocks beat to
death. Golly, my forgettery is working swell!
But, to show I am not totally out of it (yet), may I refer you to this
Internet site.
http://c2.com/cgi/wiki?ReelToReelTape

Here's a great source for more info:
http://www.churchsoundcheck.com/tra.html
And a sample from this site:
-------------------------------
There are five basic head alignment checks to make. They are azimuth,
zenith, wrap, height, and tape-to-head contact. Azimuth is probably the more
critical alignment, because this is what will cause the phase cancellations.
An improper azimuth adjustment will show up on playback through phase
cancellations, because in effect it creates a time discrepancy between the
tracks.
Azimuth is the alignment of the heads perpendicular to the direction of tape
travel. If the azimuth is misadjusted, any program recorded on both tracks
will be played back slightly out of phase.
Zenith is the alignment of the heads in the same plane as the tape. For
example, the bottom of the head can be kicked out too far, which may cause
the top tracks not to fully contact the head, and would cause the tape to
ride up on the head, snapping back down occasionally. The zenith can also be
misaligned so that the top of the head is shoved too far out. The head
should be aligned so that the tape rides against it with smooth contact to
the entire surface.
Wrap is the alignment of the head so that the tape contacts the head at the
center, aligned with the head gaps. The wrap adjustment causes the head to
swing in an arc centered on the middle of the head, and moves the center of
the head from the left to the right of center, depending on which way you
adjust the screw.
Head height is adjusted so that the tape rides perfectly centered from top
to bottom on the head. You can tell this immediately just by looking at the
tape as it rides across the heads.
Tape-to-head contact is just that - the head should be positioned far enough
into the tape path to ensure good contact with the tape. If it were too far
back, insufficient pressure would cause playback to be inconsistent.
Other than a cursory look, you probably won't need to adjust any alignment
settings on the erase head. Your first alignment will be on the reproduce
(repro) head, followed by a brief confirming check of the record head by
switching the machine to the selective synchronization status. A more
precise setting of the record head can be made during the first stages of
the record electronics alignment.
------------------------------------------------
Cheers ... back to the house remodel .. Far West Mark
(We hauled a two-ton Roberts recorder, last of my reel machines, to the
church bazaar yesterday!)



From dfischer at usol.com  Thu Aug  5 15:56:21 2004
From: dfischer at usol.com (Duane Fischer, W8DBF)
Date: Thu Aug  5 16:00:10 2004
Subject: [Vintage-Audio] Reel to Reel Info
Message-ID: <200408051957.i75JvKG4020324@smtp.usol.com>

Good stuff Mark! Thanks. 	
	
You disposed of your last real tape machine? Pray tell what do you use in its
place that is comparable? If not a Sony "l" cassette deck or DAT deck, the reel
to reel was the real winner!	
	
Duane W8DBF	


----------
From: Mark - AA6DX <aa6dx@pacbell.net>
To: Vintage home and professional audio equipment from 1975 back
<vintage-audio@mailman.qth.net>
Subject: [Vintage-Audio] Reel to Reel Info
Date: Thursday, August 05, 2004 1:26 PM

Howdy Y'all
http://home.flash.net/~mrltapes/
This site, which has the data from the Magnetic Reference Library, has quite
in depth information on the reel to reel recorder alignment, and set up.
Many items are presented in Portable Document Format (PDF), so it is advised
to have Adobe Acrobat Reader, or its equivalent, on your computer.   Be
prepared to spend some time, as it well written and documented, making for a
good read!  I have not tuned up a tape recorder since about 1983, so I
enjoyed getting a refresher course!  I remember the automated radio stations
that ran banks of reel tapes, and would like to know how many heads I have
lapped!   Used a plate of glass, varying degrees of emery paper, and then
polished with a jeweler's rouge cloth.
As to crosstalk (unwanted signal leakage from one signal path to another), I
was often replacing headblocks, and so forth, and had to adjust the az and
zenith, the wrap, etc ..  and the positioning of the tape came as part of
the game, but I don't disagree with WBob and all.  We used to get a lot of
poorly recorded ad spots from hither and yon, many small, and I mean small,
market stations used home quality stereo machines, which the jocks beat to
death. Golly, my forgettery is working swell!
But, to show I am not totally out of it (yet), may I refer you to this
Internet site.
http://c2.com/cgi/wiki?ReelToReelTape

Here's a great source for more info:
http://www.churchsoundcheck.com/tra.html
And a sample from this site:
-------------------------------
There are five basic head alignment checks to make. They are azimuth,
zenith, wrap, height, and tape-to-head contact. Azimuth is probably the more
critical alignment, because this is what will cause the phase cancellations.
An improper azimuth adjustment will show up on playback through phase
cancellations, because in effect it creates a time discrepancy between the
tracks.
Azimuth is the alignment of the heads perpendicular to the direction of tape
travel. If the azimuth is misadjusted, any program recorded on both tracks
will be played back slightly out of phase.
Zenith is the alignment of the heads in the same plane as the tape. For
example, the bottom of the head can be kicked out too far, which may cause
the top tracks not to fully contact the head, and would cause the tape to
ride up on the head, snapping back down occasionally. The zenith can also be
misaligned so that the top of the head is shoved too far out. The head
should be aligned so that the tape rides against it with smooth contact to
the entire surface.
Wrap is the alignment of the head so that the tape contacts the head at the
center, aligned with the head gaps. The wrap adjustment causes the head to
swing in an arc centered on the middle of the head, and moves the center of
the head from the left to the right of center, depending on which way you
adjust the screw.
Head height is adjusted so that the tape rides perfectly centered from top
to bottom on the head. You can tell this immediately just by looking at the
tape as it rides across the heads.
Tape-to-head contact is just that - the head should be positioned far enough
into the tape path to ensure good contact with the tape. If it were too far
back, insufficient pressure would cause playback to be inconsistent.
Other than a cursory look, you probably won't need to adjust any alignment
settings on the erase head. Your first alignment will be on the reproduce
(repro) head, followed by a brief confirming check of the record head by
switching the machine to the selective synchronization status. A more
precise setting of the record head can be made during the first stages of
the record electronics alignment.
------------------------------------------------
Cheers ... back to the house remodel .. Far West Mark
(We hauled a two-ton Roberts recorder, last of my reel machines, to the
church bazaar yesterday!)



_______________________________________________
Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer@usol.com ** 
From dfischer at usol.com  Thu Aug  5 16:20:19 2004
From: dfischer at usol.com (Duane Fischer, W8DBF)
Date: Thu Aug  5 16:23:54 2004
Subject: [Vintage-Audio] Re Glass Heads
Message-ID: <200408052021.i75KLGG4020662@smtp.usol.com>


	
Because audio tape depends upon magnetic arrangement of the ferrite particles,
how does a 'glass' head do this when it is not a conductor? 	
	
Duane W8DBF 	

From aa6dx at pacbell.net  Thu Aug  5 17:48:24 2004
From: aa6dx at pacbell.net (Mark - AA6DX)
Date: Thu Aug  5 17:53:17 2004
Subject: [Vintage-Audio] Re Glass Heads
References: <200408052021.i75KLGG4020662@smtp.usol.com>
Message-ID: <006d01c47b36$42717a00$7562ce3f@main>

http://www.jrfmagnetics.com/tapeheadintro.html
This site has about all the details on the glass bonded ferrite heads.  I
remember them in the era of the 70s in the Roberts and Akai machines.  The
Cross Field Head Akais were the hot thing for quite a while for military
folks to buy at the PX, and Akai became a well known name in consumer
electronics because of that.  Roberts, the same thing with different
badging, was more expensive and eventually was overcome by the influx of
products from Japan and Europe.
Far West Mark


From wolfbob at csnsys.com  Fri Aug  6 03:02:10 2004
From: wolfbob at csnsys.com (wolfbob)
Date: Fri Aug  6 03:04:46 2004
Subject: [Vintage-Audio] Re Glass Heads
References: <200408052021.i75KLGG4020662@smtp.usol.com>
Message-ID: <006501c47b83$4b637d00$6600a8c0@bobgk3l43zyuqn>

A glass head is not glass. It is a ferrite rather than a metalic core and
has windings just like a metal head. What they found was that on the ferrite
heads the gap would erode rather rapidly due to friction and heating with
the tape motion knocking off minute chunks of the ferrite. So Akai and soon
others found ways to coat the ferrite with a very thin layer of glass that
would bond to the ferrite and had the correct temperature coefficients etc.
and took the wear to almost nothing.  However the gap still erodes. The
erosion is a wear that is manfested in the reduction of very high frequency
response rather than the groove wear that is the case for metal heads. The
trailing edge of the gap just removed, making the gap wider and the
frequency response less. I have often found a new GX-747 that will go to 3
dB down at 34 kHz and those more worn that will do 18 kHz. The degradation
is gradual and in both channels at the same time and quite un noticable
unless you are a golden ear or a bat.

WBob

----- Original Message ----- 
From: "Duane Fischer, W8DBF" <dfischer@usol.com>
To: <vintage-audio@mailman.qth.net>
Sent: Thursday, August 05, 2004 1:20 PM
Subject: [Vintage-Audio] Re Glass Heads


>
>
> Because audio tape depends upon magnetic arrangement of the ferrite
particles,
> how does a 'glass' head do this when it is not a conductor?
>
> Duane W8DBF
>
> _______________________________________________
> Home: http://mailman.qth.net/mailman/listinfo/vintage-audio
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer@usol.com **
>
>
>


From dfischer at usol.com  Sun Aug  8 15:47:41 2004
From: dfischer at usol.com (Duane Fischer, W8DBF)
Date: Sun Aug  8 15:52:58 2004
Subject: [Vintage-Audio] Admin Post - Please Read
Message-ID: <200408081949.i78JnUG6026558@smtp.usol.com>


	
This is from Tim Miller, who handles most of the operation of QTH.NET mail for
owner Alan Waller, K3TKJ. It affects AOL users only. 	
	
Please do NOT discuss this on this list! If you have comments, send them to Tim,
not I. You can reach him at:	
	
listowner@mailman.qth.net	
	
Over the last year or so our system has been periodically blocked from sending
mail into the AOL system.  A month ago, I finally made arrangements with them to
be white listed and put an end to this once and for all.  To be white listed by
them I had to agree to receive any and all complaints logged by their users
about mail being sent from our system (we don't send spam, no problem).

While this seemed easy, I found that AOL provides their users a button on their
interface that says something to the effect that "this message is spam", and
when they highlight a message and push it, we get a "complaint" logged against
us and mailed to us.  No one at AOL reads this stuff, but they keep track of
them and after we reach a certain percentage of the mail we send vs how many
complaints we get, they block our entire system.  I've also found that the spam
button is next to the delete button, and a clueless user MIGHT use it to delete
messages.  Here in lies the problem.

I am getting plenty of these "complaints" and since AOL does not tell me who is
complaining (apparently a privacy issue), it's near impossible to find out who
they are and remove them from the system.

So, I'm asking all list owners to post a message to all of your lists reminding
AOL people not to use the "spam" button as a delete button and if they are
subscribed to your list and don't want to be, help them get off the list so we
don't get blacklisted by AOL.

Thanks for your help.  If you have any questions about this, let me know.

Tim




From dfischer at usol.com  Tue Aug 31 18:01:55 2004
From: dfischer at usol.com (Duane Fischer, W8DBF)
Date: Tue Aug 31 18:05:14 2004
Subject: [Vintage-Audio] Request For Assistance
Message-ID: <200408312159.i7VLxfG4017575@smtp.usol.com>


	
Gentlemen, 	
	
I would very much appreciate it if one of you would do an Internet search for me
to find copies of two albums by Nashville musician Floyd Cramer. He had a series
called the "Class Of ..." This started in 1965 and continued through at least
1974. I can not locate the "Class Of 1970" and the "Class Of 1971" I have
checked many stores that specialize in vinyl, but these two years simply never
show up.	
	
As most of you  know, I am totally blind, so doing an Internet search like this
can be extremely difficult using screen reading software. if one of you can find
the time to check this for me, it would be most appreciated. Thank you.	
	
Duane Fischer, W8DBF	
dfischer@usol.com	
 
