Carver ALIII Amplification

[zingo]

I may have the opportunity to get a custom pair of Carver ALIII ribbon speakers made at the old Carver shop. The specs are very similar to the original except they are sealed back (non-dipole) with a larger box/loading for the woofer. My question is, how might my 40wpc tube amp do powering those speakers? Obviously hearing is believing and I will set-up a demo if I can, but I want to make sure it's not going to be a waste of my time as the tube amp is not leaving my rig. I've heard that the Carver ALIII speakers like power, but power isn't everything either. Any feedback would be very helpful as I've heard the speakers a few months ago and they sounded good with the 150wpc SS set-up the owner was running. Thanks!

[Face]

They're pretty inefficient, so I wouldn't expect huge dynamics from a 40wpc amp unless you have smallish room. Other than them being 8ohms, I can't find any impedance data on them, so I don't know exactly how tube friendly they are. Is the woofer self powered?

[zingo]

Here are the specs I found:

Response: 34 Hz to 20 kHz +- 3dB
Impedance Nominal 4 ohms
Sensitivity 86 dB ref. to 1 watt at 1 meter
Crossover 150 Hz
Ribbon Driver 48-inch dipole ribbon
Woofer 10-inch Quasi-butterworth 3rd order aligned woofer system, which fires downward in a circular pattern.
Recommended Power Up to 575 watts per channel; 65 watts minimum, 8 ohms rated.
Net Weight 80 lbs. each
Dimensions 14.5Wx16.5Dx72.5H

[zingo]

They're pretty inefficient, so I wouldn't expect huge dynamics from a 40wpc amp unless you have smallish room. Other than them being 8ohms, I can't find any impedance data on them, so I don't know exactly how tube friendly they are. Is the woofer self powered?

The woofer is passive just like in the original design. The option since my integrated amp has subwoofer and/or amplifier output would be to get a dedicated amp for the woofers. That might lighten the load on the tubes as they would be dedicated to the ribbon. Granted, that ribbon would still not be as easy a load as my current horns, but it may make a difference.

[heiney9]

40 wpc of tube power I think is wishful thinking for an 86dB efficient speaker that uses a ribbon and is 4 ohms nominal. If it were me I'd try to get my amp there for a demo to see if it's compatible for my listening habits, etc.

H9

[Face]

It could work, I used a Stingray in Triode(20wpc) on less efficient speakers. But in your case, I have no idea what the impedance curve looks like, desired SPL, etc... Bi-amping will help a lot, even a plate amp would be fine playing to 150hz. H9's suggestion of a demo using your amp is a great idea too.

[zingo]

A demo would be required before I make any move, but I was just trying to feel out if I was doomed from the start with tubes and ribbons.

[F1nut]

My question is, how might my 40wpc tube amp do powering those speakers?

Poorly.

[cnh]

I remember hearing a set of Carvers (Original 4 X 12" and gold ribbons) on two Carver Silver 7s play a symphony and thinking that the mono-blocks could just about handle powering them but were quickly approaching their limits. I must say, though, that Carver Amazings produced some of the most realistic concert hall performances I've ever heard. I'm not sure, that they were as 'amazing' on more pedestrian forms of music. But, they certainly excel at reproducing the concert hall ambiance, but boy are they power hungry!!

cnh

[zingo]

Thanks for the realism Jesse; it's always helpful. Well the combination isn't looking good, but they are a cool pair of speakers, and I might as well see if I can get a demo with them and my amp to listen for myself. Thanks!

[tonyb]

Poorly.

Straight and to the point....gotta love it. Agree with that assesment too.

[zingo]

It looks like I may demo the speakers with a higher power class-D amp as I just don't feel the tubes would cut it. Class D is an interesting topology to be that I don't think sounds good with all speakers. I know those amp LOVE low impedance loads which is while they are often used for subwoofers, but maybe the ribbons would be a good fit as well. Who knows, maybe the combination of tube pre, class D amp, and ribbons will be delightful...

[zingo]

Update: Yesterday I picked up a custom pair of H/K775 monoblocks. The original transformer died in one last year, so the owner had both replaced with an external dual-mono power supply and had the amps tuned up at the same time. They sound great and are nice high-current amps. I hear they even go to 2 ohms if pushed, and I'm sure the new power supply only helps the amps.

I currently have them hooked up to my Klispch with a tube pre and they sound really nice; differently centered and focused than the tubes, but pleasant. I will be demoing the ribbons with these HK775 to see what I think.

[Big Dawg]

I may have the opportunity to get a custom pair of Carver ALIII ribbon speakers made at the old Carver shop. The specs are very similar to the original except they are sealed back (non-dipole) with a larger box/loading for the woofer. My question is, how might my 40wpc tube amp do powering those speakers? Obviously hearing is believing and I will set-up a demo if I can, but I want to make sure it's not going to be a waste of my time as the tube amp is not leaving my rig. I've heard that the Carver ALIII speakers like power, but power isn't everything either. Any feedback would be very helpful as I've heard the speakers a few months ago and they sounded good with the 150wpc SS set-up the owner was running. Thanks!

Are these the ones being made out of aluminum in conjunction with Bob Carver? I'd be interested in hearing your assessment. Have you spent any time with any original Amazings (including platinum and silver), or ALIII or ALIII+?

[zingo]

No; This pair of ALIIIs was customized at the Carver shop back when it was the original company. One of the techs wanted a pair of ALIIIs that was not bi-polar and could be placed against the wall. They then figured out "correctly" how to close the back and then they ran the woofer box up the back of the speaker, increasing its volume and changing/improving bass response. This does remove the magical bipolar element of listening to open ribbons, but it does make them easier to place and less effected by a room. I have not heard an original pair or Amazings, but I did like the sound of the custom ALIIIs at my friends house.

[zingo]

[Face]

Shouldn't they be futher from the rear wall?

[nooshinjohn]

You may want to try a Sunfire 300/2 on those. It is my understanding that they are a match made in heaven. Beautiful speakers btw. I am curous to see how the mods were done on these.

[zingo]

These speakers are one of two made custom from the original Carver shop. The back of the ribbon was closed with felt, the woofer was moved to be from facing below the ribbon, and the box is rear ported and runs the length of the ribbon. I've not heard the original ALIII, but the bass on these is impressive and I'm sure improved by the large box. The crossovers were also adjusted to compensate for the customizations. They are no longer di-polar so wall placement is not an issue which is nice. I knew these were a hard load to drive, but at around 9 o'clock on the volume, my H/K 775s are pegging at about half their output, but they do sound good and it think they are a good match; or at least not a bad match. This is my first experience with ribbons and I'm surprised by how different their off-axis response is; almost the opposite of my horns. I still really like the directness and clarity of the horns, but these speakers are extremely engaging and make for an excellent listening experience.

More to come as I play with different amps on them...

[F1nut]

The back of the ribbon was closed with felt

That was how they came starting with the Plat's. It doesn't stop the bi-polar design, just lessens it a bit allowing for closer rear wall placement.

[zingo]

Interesting Jesse; thanks for that piece of info on the Plats.