Best SET amps vs. CAT? CAT destroy all, or different tastes?

caesar

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I have heard a good number of guys tell me (all independent of each other, so this is not group-think) they would take CAT over any SET, regardless of price.

I'm not into SET gear, but I understand they have a great midrange but are compromised in bass and elsewhere. CAT, on the other hand, doesn't have the euphonic "fat" in the midrange, and at the same time is good everywhere else.


So does CAT pretty much destroy all SET gear, unless the listener prefers only the midrange-focused music?
 

JackD201

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I'll take the top VAC over the CAT. I'm not associated with either in fact CAT is not represented over here and VAC is competition. That said, SETs are usually characterised as sagging at the extremes because most people have heard them mated with speakers that need more juice. With the right speakers even fleas like 45s and 50s can be quite linear (at leat into the lower mids, upper bass). With speakers like those I have a hard time believing a high powered PP amp can better a top notch SET amplifier. I very well could be wrong of course but I doubt it.
 

caesar

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I'll take the top VAC over the CAT. I'm not associated with either in fact CAT is not represented over here and VAC is competition. That said, SETs are usually characterised as sagging at the extremes because most people have heard them mated with speakers that need more juice. With the right speakers even fleas like 45s and 50s can be quite linear (at leat into the lower mids, upper bass). With speakers like those I have a hard time believing a high powered PP amp can better a top notch SET amplifier. I very well could be wrong of course but I doubt it.

Seems like a very plausible explanation, Jack. What are the characteristics or specs of speakers that would work well with a SET?

And as for VAC vs. CAT, I think they are both top notch. I always thought VAC was a bit warmer than CAT, but I never heard them side by side. In your experience, how are they different?
 

JackD201

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Seems like a very plausible explanation, Jack. What are the characteristics or specs of speakers that would work well with a SET?

And as for VAC vs. CAT, I think they are both top notch. I always thought VAC was a bit warmer than CAT, but I never heard them side by side. In your experience, how are they different?

I feel the CATs I've heard don't quite have the "flow" in the micro details the VACs do. It's what might be analogous to grain is a solid state device, something I attribute to zero crossing distortion. This is where SETs excel because they never cross to begin with. Theres always a charge. Please EEs and tube designer gods do not strike me down with lightning, I'm doing the best I can with my limited understanding and vocabulary here. Anyway the VACs seem to have the bias thing down pat and are as close to SET as I've heard from PP and that is having them sitting right next to a Wavac 833. The big CATs I've heard with big Hansens (love those speakers too by the way) and while I honestly had no complaints, but asked to split hairs here, yeah I'd say that at least the big CATs I heard some years ago lagged in that regard. Who knows what changes Mr Stevens has made since then so for all I know that's been dealt with as well.

As for specs I suggest as Steve does but just as important a flat impedance curve. I'd also look at the mechanical roll off of the lowest octave driver. For the typical 300b and lower I'd say 105dB to be linear, about ~100dB for the 6c33s, 211s and 845s, ~95dB for GM70s, T1610s ~90 for the transmitter tubes. It should be noted that I have seen a number of amps fall flat ( I support the local tube community by commissioning works) because of poor transformer work. One thing the top notch SETs have are good OPTs. I kind of understand why ralph did away with them altogether. They are that "make or break".


The X2 is one of those outliers having the large short throw mid bass driver. Is it 11" Steve? This driver makes it VERY SET friendly. It is large, fast and needs little excursion to hit SPL.
 
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Steve Williams

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The X2 is one of those outliers having the large short throw mid bass driver. Is it 11" Steve? This driver makes it VERY SET friendly. It is large, fast and needs little excursion to hit SPL.


The mid bass driver is actually 13"
 

DaveyF

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Yup, CAT destroys all, LOL. That's why they are called the MIGHTY CAT!!

Seriously though, the sound of CAT gear is not really the same as the sound of SET. IMHO, both have a deserved place in the audio world. Both serve a particular purpose and depending on the speaker, one could easily prefer SET over CAT or vice versa.
I do think that CAT is a far more versatile amp and one would be unlikely to go wrong in most any set up...which cannot really be said for almost all SET amps. Get it wrong with an SET and you are in trade mode quickly.
 

the sound of Tao

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Great push pull eg CAT, Conrad Johnson, Jadis, Audio Research are all genuinely great... The best of SET... Kondo, Silbatone, Wavac, Shindo Lamm et al. are probably beyond great... Just a personal perspective tho and nothing more.
 

LL21

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Great push pull eg CAT, Conrad Johnson, Jadis, Audio Research are all genuinely great... The best of SET... Kondo, Silbatone, Wavac, Shindo Lamm et al. are probably beyond great... Just a personal perspective tho and nothing more.

I have spent many years with CJ amplification and always felt it was great. i once spent an afternoon at home auditioning Shindo and found it mesmerizingly good. It was not their amplification but their preamp, so not quite part of this SET/PP discussion, but i have to say i totally got the appeal. I ultimately went up in the CJ line instead, but i could totally see the Shindo appeal, and i also have heard a sensational system powered by Kondo's best. I would be very interested to hear Lamm and Wavac someday.
 

the sound of Tao

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I'm with you and would feel indeed very fortunate to live with any of these extraordinary works of art. We are at every level spoiled for choice, the audiophile might be somewhat of a dying breed but we are certainly going out in style lol
 

LL21

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I'm with you and would feel indeed very fortunate to live with any of these extraordinary works of art. We are at every level spoiled for choice, the audiophile might be somewhat of a dying breed but we are certainly going out in style lol

Hah! I like that...! At the same time, we may yet get the last laugh...with headphone going for hundreds to thousands on the 'wider market'...i think we may yet see a renewed interest in high quality audio equipment for the home at some point in the future as those who 'grew up' on high end headphones start to buy their first nice home and want to put better quality audio in the house. Given the housing market, that might be a little while, but i could see that happening.
 

JackD201

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The mid bass driver is actually 13"

There ya go. Even better. That's a typical size for a pro long throw midrange. At least it was until line arrays and gobs of affordable Class D and Class H came to the fore. Back in the golden days of VOTTs and JBLs drivers app. this size with short excursions were made to produce ~5Khz and below IIRC.

My speakers are 94dB but will crap out in the bass with even 50wpc. I've heard Steve's. They can punch a hole in your chest with 30. His subs came in very low, I'd guess around 50Hz, maybe lower. The X series really is an outlier as far as dynamic speakers and SETs go. I can't really think of any current production, non-active bass, large format box speakers that can match it in the mid-bass with so little juice. There are a few small ones like those from Living Voice, big 'uns, much rarer. If anyone can name some more that would be great. I'd really like to know.
 

LL21

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There ya go. Even better. That's a typical size for a pro long throw midrange. At least it was until line arrays and gobs of affordable Class D and Class H came to the fore. Back in the golden days of VOTTs and JBLs drivers app. this size with short excursions were made to produce ~5Khz and below IIRC.

My speakers are 94dB but will crap out in the bass with even 50wpc. I've heard Steve's. They can punch a hole in your chest with 30. His subs came in very low, I'd guess around 50Hz, maybe lower. The X series really is an outlier as far as dynamic speakers and SETs go. I can't really think of any current production, non-active bass, large format box speakers that can match it in the mid-bass with so little juice. There are a few small ones like those from Living Voice, big 'uns, much rarer. If anyone can name some more that would be great. I'd really like to know.

Learn something every day...thanks Jack. Would be interesting to hear how Steve has set his sub crossover rolloff. I cut off my Velodyne above 40hz with a 48db rolloff.
 

caesar

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I'm with you and would feel indeed very fortunate to live with any of these extraordinary works of art. We are at every level spoiled for choice, the audiophile might be somewhat of a dying breed but we are certainly going out in style lol

Maybe even too much choice, Tao, making heads spin and freezing the ability to pull the trigger...

Also, just noticed in your signature a very interesting system combination of Shindo and Sanders on your Maggies. Seems like polar opposites. Out of curiousity, have you tried Bryston with Shindo in your system?
 

andromedaaudio

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I dont know ive only heard so much amps , but its amplifying at a very high/powerfull and satisfying level , thats all that matters .
Its all about taste which is very good otherwise there would be only 1 amplifier and 1 speakerdesigner to supply the market .
What Cat does have is a powersupply (capacitator bank /transformers) that are the largest ive seen on any tube amp CAT also uses a lot of tubes to reach the amp output compared to the competition , enough to unleash a hurricane.
Mine uses 8 KT 120 tubes for 100 watts on 1 channel.
The only downside i can think of is that the poweramp is producing some transformer hum
 

rockitman

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I dont know ive only heard so much amps , but its amplifying at a very high/powerfull and satisfying level , thats all that matters .
Its all about taste which is very good otherwise there would be only 1 amplifier and 1 speakerdesigner to supply the market .
What Cat does have is a powersupply (capacitator bank /transformers) that are the largest ive seen on any tube amp CAT also uses a lot of tubes to reach the amp output compared to the competition , enough to unleash a hurricane.
Mine uses 8 KT 120 tubes for 100 watts on 1 channel.
The only downside i can think of is that the poweramp is producing some transformer hum

with Cat, the transformers are out in the open. Try some Stillpoints LP1 pucks on top of each trans to damp the vibs...
 

DSkip

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I've run SET amps for at least 10 years. Best advice is to gave a very efficient speaker. Mine are 95 dB sensitive so no problem.

I'm going to go against this and suggest that efficiency is a very small deciding factor as long and they are 87db or better. Mind you my set amps are 28 wpc. What I find to be a bigger factor is the impedance curve of the speaker. My set amps do absurdly well with 8 ohm nominal speakers. Throw th on 4 ohm speakers, and they fall on their face.
 

andromedaaudio

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with Cat, the transformers are out in the open. Try some Stillpoints LP1 pucks on top of each trans to damp the vibs...

In the open ? they have a metal casing protecting the trannies and caps with airflow openings , ive tried some weightdampening which is quite effective on reducing casing vibration but besides that you have transformer hum , the electricity sets the windings in motion , i dont assume you mean putting a stillpoint directly on the windings
Boulder pots the transformers and puts great effort in reducing noise and vibration , so probably they dont need much cooling .
My zanden 300 B Set also had some transformer hum , the Graaf GM 200 OTL had it to a greater extend still , regarding SET versus ...., the CAT is also triode design , and i am glad i traded the zanden for the one i have now , i think all this Single ended triode magic talk ? comes down to execution of design , they can all sound good , allthough 300 B SET designs dont deliver the bass control i want , plus in the end " Power corrupts " .
Maybe the Lamm set or wavac or another based on a different higher power tube might give different SET results

boulder transformer by andromeda61, on Flickr
 
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