Carver Amazing Silvers

Yep, the linked Service Manual covers the Silvers as well as the Platinums, just keep scrolling the document (or jump to p. 11).

Ah! I see the schematic. But I still don't see a woofer wiring diagram. Are they just all in parallel? Seems like I remember mine being wired some other way.
 
As I understand it, there were different tries and the woofer wiring patterns were sometimes done one way and sometimes another--not necessarily following the published SM. Think 'work in progress'.

The set I had were Originals and the last owner did them up Series-Parallel, no way to know what they were originally. I tried different ways and wasn't ever really satisfied but I never had 1200 WPC to do them justice. Tarior owns the only amp I ever had that came close. :thmbsp: Kudos to him for getting that giant working again.

But I never had the ribbons, just the woofers.
 
Bad news, two of the woofers on the problem speaker actually read "open" and at their extreme inward excursion have what appears to be a delaminated winding from the voicecoil.
Not. Good.

:tears:
 
Bad news, two of the woofers on the problem speaker actually read "open" and at their extreme inward excursion have what appears to be a delaminated winding from the voicecoil.
Not. Good.

:tears:

I thought he just replaced those with new OEM woofers... :scratch2:
 
I thought he just replaced those with new OEM woofers... :scratch2:

Yep.

I think there's a relationship here with the wiring issue and non-working ribbon, same speaker. have fun Will. I know you're motivated to be able to listen to these.
 
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I thought he just replaced those with new OEM woofers... :scratch2:

What make of woofers were those? Until the late 80' Carver used Sony woofers, but they were inadequate so they switched to Tonegen woofers in all the subsequent models.

Best Regards,
TerryO
 
Yes, there's a thread spanning a few years on these on the carveraudio forum: http://www.carveraudio.com/phpBB3/viewtopic.php?f=15&t=1516

Well I guess we have to find information where we can. Here's the lowdown on the Carver Amazing Woofers:

I created the Carver Amazing woofer system and Large Area Ribbon (co-authored with David Graebener) for Bob Carver in the mid 1980's as a consultant.

One question that is often asked was whether the Amazings had a high or low Qms. The Qms was quite high, we attempted to achieve a Qms of nearly 10, which is required if one is going to end up with a Qt of much greater than 2 and still maintain reasonable efficiency.
The trick is to be able to maintain 'linear' Qms. One of the big problems we found early in the development of the Hi-Q open baffle was that many of the Hi-Q drivers have Qms values that change depending on level. This non-linear Qms causes a non-linear Qts, which causes a non-linear frequency response with level...i.e. compression/distortion. This Qms modulation is one of the main reasons that some have found higher Qts drivers to sound bad. It’s is not the higher Qts, but the Qms -> Qts nonlinearity that causes the poor sound quality. Proper Qts match to baffle cut-off frequency will perform quite perfectly, even for higher Qt values if the resulting frequency response is flat and the Qt value is maintained at all listening levels.
The Amazing suspension components, spider and surround, took nearly 9 months to work through the design problems to chase out the non-linearities. No one had optimized high-Q woofers previous to the Amazings so the driver vendors were not able to help. We had to drive the component development ourselves. It was hard to get spiders with low enough damping (they actually call them dampers in Japan) to achieve high-Q and then it was even more difficult to develop spiders and surrounds that maintained constant damping.
Okay, that is probably more than what anyone wanted to know on that subject, but I felt it was important to start getting past this myth that “high-Q drivers are bad”. It is a systems approach. High-Q is not inherently bad, but ‘mismatched’-Q is. A high-Q driver is appropriate when matched to a ‘low-Q baffle’, just as a Low-Q driver is appropriate to match to a ‘high-Q’ Helmholtz enclosure.
The original Amazings had even higher Qts and lower Fs than the later Series. As is often suggested, lower Fs requires higher-Q, but this becomes problematic. For a fixed baffle cutoff frequency, with the standard 6 dB/octave high pass characteristic from cut-off down to the resonant frequency, the ideal high-Q gain would match that first order slope over the bandwidth from cutoff to fs. Unfortunately, the 12 dB of gain we needed in the original Amazings to achieve reference level at the Fs of 20 Hz required a Qts of about 4. This created a narrow band peak that doesn’t match the smooth, 6 dB roll-off slope of the open baffle. Because of this we had to use some shaping networks to smooth things out from 25 Hz to 100 Hz. We ended up with a fairly smooth response with a peak at 20 Hz and Fc at 17 or 18 Hz.
The later Amazings had a new lower mass paper cone woofer to replace the heavier honeycomb devices in the originals. We were able to get the moving mass down to less than 15 grams, which is quite low for a 12” woofer, but required for getting decent efficiency.
The Fs was raised to 30 Hz and the Qts was lowered to a value between 2.5 and 3. This worked much better in matching the Fs, Qts, and baffle Fc to get a smoother response and much higher efficiency.

~~~~~~~~~~~~~~~snip~~~~~~~~~~~~~~~~~

Warmest Regards,
Jim
 
Yep.

I think there's a relationship here with the wiring issue and non-working ribbon, same speaker. have fun Will. I know you're motivated to be able to listen to these.

I am not concerned that the ribbon is non-functional but stranger things have happened (I really hope it works though)

They are mighty less efficient than my SL7s but that could be expected.
 
http://www.dynavox.com/product_info.php?products_id=5&osCsid=f0c8e414478f1bf28f01e0a1a77d8044

Prices are up, I think I got them for $35 each about a year ago. cheap enough to replace instead of refoam. still have the original woofers in storage.

I remember a thread about someone wanting to replace woofers in the Amazings that got a deal on "OEM" replacements. I've also seen an epay ad for Exxxance replacements. These will work, after a fashion, but the specs really don't match up as well as they should. They were never intended for this application and are more of a generic design according to the designer.

Here's the thread, I thought that I remembered it:

http://audiokarma.org/forums/showthread.php?t=220360&highlight=Carver+Amazing&page=3

Best Regards,
TerryO
 
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Grill cloth ordered for the rear of the untis. New woofers are pending due to a possible purchase by SpeakerLabFan.
 
I've started to work on these again after a 5 month break. I've suspected the crossover caps as a source for one ribbon not working because it measured the same as the working ribbon as far as DCR goes. So I soldered together some capacitors for the crossover today, I might work on it more later this week, but no promises.
This could get interesting...
 
Byrd, you need to get those done. If you get those finished, properly placed and properly amplified, you will have an audio epiphany, guaranteed. :yes:
 
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