Sunday I went over to a friend's house to look at a Western Electric 12" driver he had pulled from an old console. It the model 728b. A real gem.
This is a 12" fullrange from the late 1940's. Super well built and heavy. In the console it was driven by a parallel P-P 2A3 amp, yikes! The console cost near $1200 at the time, or about $11K in today's dollar.
Below I have attached some quick FR measurements that I did. Not your usual 12 driver. Normally I don't show such an expanded amplitude scale, but here it was done to show the low distortion of the driver. 3rd harmonic is shown, but the others are in line with this, dropping off naturally from 2nd thru 7th. A very clean driver. Notice the lack of bad cone break up.
We measured it "naked" in a chair, then in a loosely sealed box of about 1.8 cubic feet. It did well. Of course it beams, but it's a 12" cone with no whizzer. It was driven by a mono 6L6 P-P amp for the tests. DCR is 3 ohms, a surprise for a vintage driver.
They sure don't make then like this any more.
This is a 12" fullrange from the late 1940's. Super well built and heavy. In the console it was driven by a parallel P-P 2A3 amp, yikes! The console cost near $1200 at the time, or about $11K in today's dollar.
Below I have attached some quick FR measurements that I did. Not your usual 12 driver. Normally I don't show such an expanded amplitude scale, but here it was done to show the low distortion of the driver. 3rd harmonic is shown, but the others are in line with this, dropping off naturally from 2nd thru 7th. A very clean driver. Notice the lack of bad cone break up.
We measured it "naked" in a chair, then in a loosely sealed box of about 1.8 cubic feet. It did well. Of course it beams, but it's a 12" cone with no whizzer. It was driven by a mono 6L6 P-P amp for the tests. DCR is 3 ohms, a surprise for a vintage driver.
They sure don't make then like this any more.
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Yeah, the cone is a little unusual with that bend toward the dust cap. I don't know what that does.
The driver sounds good, certainly does not sound "modern." Very clean, and you can hear that on sweeps and music. But to me, it does not sound as good as it measures, something odd in the midrange - like a tonal balance issue. Still, I did not get to hear it in the console where it belongs.
These drivers fetch north of $1200 any day. Some go for twice that or more.
The driver sounds good, certainly does not sound "modern." Very clean, and you can hear that on sweeps and music. But to me, it does not sound as good as it measures, something odd in the midrange - like a tonal balance issue. Still, I did not get to hear it in the console where it belongs.
These drivers fetch north of $1200 any day. Some go for twice that or more.
Bell Labs and all the technical, financial 'backdoor' support this implies to develop bleeding edge materials, manufacturing technology back in the early '30s when it was originally created, hence the primary reason for a ~11 k adjusted pricing. Consider that at least some of their designers made six digit salaries during the Depression according to a then crusty 'old' engineer I knew back in '64 that had apprenticed there during audio's 'golden years'.
We can easily best it today by a fairly wide margin, but the cost! If you have to ask the price, you can't afford it.
GM
Big dip around 4.8kHz IMHO would be very audible, as well as the broad dip at 500Hz and the higher Q one at 950Hz, a few peaks of sufficient amplitude as well - otherwise a remarkably good level of performance for a 12" driver. I'm sure it beams, and fairly badly at that..
I think the geometry was designed specifically to control breakup modes and the cone area probably is not constant with frequency either. (Decoupling part of the cone above some predetermined frequency.)
How were the measurements performed?
This looks a lot like the big, big brother of the 755..
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cool,
my question is,
how would a driver like this compare sonically to a modern driver with similar ts parameters?
is there a benefit to owning a driver like this apart from curiosity?
reason i ask is because i see vintage/older audio stuff in thrift stores regularly, if it has a sonic benefit i might have to start buying some of it.
but if theres no real sonic benefit, ill just buy a driver new and leave the 300lb cabinet at the thrift store
my question is,
how would a driver like this compare sonically to a modern driver with similar ts parameters?
is there a benefit to owning a driver like this apart from curiosity?
reason i ask is because i see vintage/older audio stuff in thrift stores regularly, if it has a sonic benefit i might have to start buying some of it.
but if theres no real sonic benefit, ill just buy a driver new and leave the 300lb cabinet at the thrift store
By the look of those low distortion results, they may in fact be showing a lot
of the amps distortion (6L6 PP). It would be interesting to do them with a
VLD SS amp and see if there is any difference.
Awesome looking driver!
Z
Pretty much as you see them, mic, amp, soundcard, HOLMImpulse. Nothing definitive, just a "wonder what it looks like" view. Below is the driver popped in a box for a listen. Just the 12 is connected
Yeah, we were going to use a SS amp, but opted for valve. Not unhappy with the results. But until I hear these in an optimum setup, I would have other ways to invest $3000 dollars in a pair of drivers. Real collector's items, for sure.
There was a second console with the same 4X 2A3 amp, but a Jensen fullrange speaker. The Rek-o-kut turntable is sweet.
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