[Boatanchors] Yet another tube question

[Albert LaFrance]

Here's a great example of "audiophool" products:
http://www.audioasylum.com/audio/general/messages/104180.html

Albert LaFrance

----- Original Message ----- 
From: "Bob Young" <youngbob53 at msn.com>
To: <boatanchors at mailman.qth.net>
Sent: Monday, February 05, 2007 12:44 PM
Subject: [Boatanchors] Yet another tube question


> I'm a musician, a bass player to be exact and I use 300 WRMS Ampeg SVT's 
> with 6 6550's, 3 in parallel on each side. I didn't buy matched tubes the 
> last time although I agree they are clearer sounding, I like a little grit 
> in my sound. Also matched tubes for a guitar player not only gives him more 
> power it also makes the distortion that most guitar players use a little 
> more uniform and clean (is not a contradiction, really). Audiophool for me 
> starts when an audiophile feels that he "hears" a difference between #14 
> lamp cord speaker cable and some "magic" cable for 100 bucks with gold 
> plated connectors. I've used matched tubes in my audio stereo amps though 
> and have used matched sets in my SVT, just can't justify the added expense 
> for them when I'm playing rock n roll loudly and can't hear the difference 
> anyway. I do buy good tubes though and next time probably will buy matched 
> sextets of them, Svetlana makes good tubes for Russian, last a long time and 
> sound good,
> 
> Bob young
> Millbury, Ma
> KB1OKL
> >
> >Message: 2
> >Date: Mon, 5 Feb 2007 19:20:23 +1100
> >From: "Brian A Clarke" <brianclarke01 at optusnet.com.au>
> >Subject: Re: [Boatanchors] Yet another tube question
> >To: <boatanchors at mailman.qth.net>
> >Message-ID: <012f01c748fe$7c19b0e0$0202a8c0 at Belkin>
> >Content-Type: text/plain; charset="iso-8859-1"
> >
> >Just a moment fellas,
> >
> >Selecting tubes for RF PAs doesn't need to be too accurate. What you need 
> >to
> >bear in mind is that if you have a set designed to deliver 400 W from two
> >tubes in parallel, and one of those tubes is a bit low in performance, and
> >the operator tries to get the full bottle, then the life of both tubes will
> >be shortened because of the excessive temperature rise. Balance within 20%
> >is probably close enough.
> >
> >In audio applications, there is a very good reason for balancing tubes'
> >emissions much more accurately, and that is that if there is an imbalance,
> >then the secondary of the output transformer will be passing some net DC
> >that will go towards magnetising the core and thus reducing the inductance.
> >This will change the shape of the hysteresis curve and have two effects -
> >distortion on high powered peaks that wasn't there before, and loss of
> >bass - the OPT needs inductance in order to have enough reactance at the
> >lower frequencies. For stage musicians, balancing the output tubes allows
> >more power output before distortion sets in - very handy. Most musically
> >inclined folks can hear these effects quite easily - dubbing them
> >'audiofools' is a sign of ignorance.
> >
> >73 de Brian, VK2GCE.
> >
> >
> >
> 
> 
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