[Vintage-Audio] Speaking On Speakers

[JM/CO]

There were several factors at work here. First, this must be viewed in the
context of a timeline.
When "Hi-Fi" was new ( post WW II ), it was very expensive, and therefore
only affordable to a relatively few, relatively "sophisticated" listeners.
The dominant music of choice was classical, and most people sat in one spot
and listened. Audio was not an instant mass consumer success like TV was at
the same time.
The Klipsch corner horns were first produced in 1946. They are among the
most efficient speakers ever produced. The dominant electronics of the time
called for  power amplifiers which tended toward (very ) low power, thus
making the high efficiency of horn loaded / bass reflex speakers desirable.
A 12 watt amplifier, such as a Brook,  was considered "overkill". There was
great debate in the Audio Press as to whether Triode or Pentode technology
was superior.The best pentode vacuum tube audio amplifier circuit ever
developed, the McIntosh, was first introduced in 1947. Early versions were
only 15 watts.
Wealthy folks also tend to live in large houses, and like to look at pretty
furniture. Most of these early speaker cabinets fit this requirement nicely.
As we moved into the 60's, and "stereo" began to dominate, audio technology
became the technology of choice of the masses, who, for the most part, did
not have critical listening skills, nor the large living areas required for
the older, larger designs. Also, two speakers took up more room than one.
Listening habits had also changed. FM Stereo began to broadcast in 1959, and
stations that had, for years, been locked into a classical format, began to
change. The music of choice had become Rock, and while some listeners wanted
to sit and listen while imbibing their favorite substances, others wanted to
dance to "punchy" bass, and "sizzling" highs.
Another factor was the development of more powerful  amplifiers. The pentode
"Williamson" and McIntosh designs gave way to solid state beasties, which
could achieve a superior power to weight ratio. As power pushed up, speaker
efficiency could afford to be lowered, and the "air suspension" or "acoustic
suspension" speakers ( first designed by JB Lansing ) began to dominate. The
overall system would equal, in loudness, the capabilities of earlier
designs.
As we moved into the '70s, these two consumer trends, toward smaller size,
and more power available, led to speaker designs that were very in-efficient
( Bose 901, AR-3, Ohm "A" etc. )  but could be powered by relatively in -
expensive large amplifiers to produce decent sound.
By the early 1970's, power amplifiers of up to 350 watts per channel ( Phase
Linear / Crown ) were being used in home audio systems.
Unfortunately, the quality of the components in these "consumer grade"
speakers left something to be desired. There are truck - loads of 60's and
70's vintage speaker systems showing up in local landfills these days
because the foam suspension material for the woofers / midranges has all
rotted. By contrast, many of those old "boatanchor" speakers made by such as
Electrovoice, Bozak, Altec Lansing, Tannoy, J. B. Lansing etc, etc, are
still working just fine, and are highly sought after and expensive today.
Oh- one other thing. Electromagnets, as a speaker component, disappeared
before WW II. ALNICO was discovered ( I think ) in 1938.
Chuck N1LNH
-----Original Message-----
From: Duane Fischer, W8DBF <dfischer@usol.com>
To: vintage-audio@mailman.qth.net <vintage-audio@mailman.qth.net>
Date: Tuesday, July 30, 2002 4:57 PM
Subject: [Vintage-Audio] Speaking On Speakers


>
>
>Now I realize I am probably drawing a battle line in the sand by
approaching
>this topic, but I am bored, it is hotter than a Beavers butt in a blow
drier in
>MI and I need some excitement besides listening to the condensation water
drip
>off the toilet tank onto the bathroom floor!
>
>So here we go:
>
>There were many different designs for speakers in the middle to late
sixties.
>Some were air suspension, some were floor firing, some used permanent
magnets,
>some used electromagnets and some used ... Some cabinets were infinite
baffle,
>some were bass reflex and others were folded horn. What was the supposed
>advantage of the air suspension and other designs over the traditional pm
>speakers with front firing ports? Leave price out as a factor, I understand
the
>cheaper concept, which is generally not related to better or more
efficient.
>
>Thanks.
>
>Duane W8DBF
>
>
>
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