Is there a Solid State amp that can satisfy a SET guy?

@almarg Thank you very much, Al. The posts caught my attention as I am in the middle of choosing a 211 or 845 amp. You’ve allayed the concerns the posts raised.

@atmasphere Can you comment as well? Thanks.

I’m open to hearing from all four members from my initial post, on the topic, should you have additional and/or other perspectives to share.

Thanks in advance.

Hi again, David. I would add that it follows from what I said about output transformer quality (and various other factors as well) that generally speaking I would expect a 211 or 845 amp to cost a great deal more than a 300B amp providing comparable sonic quality.

Good luck in your search! Best,
-- Al

@almarg  Al, Yes indeed! Those price differentials!!! : )

I'm also curious about the comments on Parallel builds of the 211 /845 being superior to single tube 211/845 based amplification?

I'm also curious about the comments on Parallel builds of the 211 /845 being superior to single tube 211/845 based amplification?

I can't shed any light on that, David.  Best,
-- Al

Thank you, Al. 

I would second the recommendation of your friend regarding the Alephs being SS amps that are closest to tubes. They are "single ended transistor" designs. But to sound their best, your speakers need a nominal (not just recommended) impedance of better than 4 Ohms. And for HT, you would likely need close to 100W for a large to medium room. I’ve been using the Aleph 2 monos since the mid 90s. Used them for 2.1 audio and for HT and other setups. No harshness and there is a sweet midrange. They do get hot. But so do tubes.

A Parallel SET amp will have half the output impedance of a single-tube SET - all else being equal. That will have a positive result driving a typical speaker with a varying impedance curve!

The short answer to the OP’s question is no.  
And for the OP to ask means he already knows.

@wig Thanks!

@roberjerman Thank you.

It is kind of impossible to find an Aleph 3!
There are a couple of Aleph 5s but I think the 3 may be better?
An amp designer friend says that "the lower the power the better".
Don't know if that is necessarily true but may apply to SET amps?
Should I try the Aleph 5? Not sure if it is as sellable as a 3 if I don't like it.
Then there are the comments that there is NO SS amp that can satisfy a SET 300B guy. I don't know for sure if that is true.
Three amps I would now be interested in trying are:
Pass Aleph 3 (or 5?)
Bakoon 13R
Pass XA 25!

BTW-The ongoing thread for months now on its 214th page is @whitecamaross discussion and many videos all about SS amps (cables, et al). Not a tube amp considered at all... well maybe an AR or two.

Re the Bakoon 13R, be aware that the input impedance of its RCA input is only 10K, which will not be a good match for many and perhaps most tube-based components.

I believe the other input choice provided by the 13R, a "Satri Link," would only be usable if driven by a Bakoon component providing that kind of output.

Regards,
-- Al

I would opt for the Aleph 5 (rather than the 3) if doing some HT.

Why do some people use question marks after statements?

To indicate that their statement should be read with an uptalk intonation

Have used SET amps for the last four decades. A SET amp produces a 3d sound to each instrument and the stage which contributes to music sounding real. The SS amps that for me capture much of this is the Pass XA25 and FW SIT3, i was so impressed with the XA25 that i purchased one 2 months ago. They do take about 100-150 hours to sound their best and an initial one hour warm up.

""To indicate that their statement should be read with an uptalk intonation."
I do understand that, but it's written word, and should be written correctly. It's annoying.

It’s just as annoying as people, who use uptalk when they speak.
But, since it’s an audiophile forum, they can get away with this kinda stuff. After all, all we care about is how their equipment sounds, not how they talk :-)

Yes there is only one : Robert Koda.
Better than Dartzeel.

@rh67 

Have used SET amps for the last four decades. A SET amp produces a 3d sound to each instrument and the stage which contributes to music sounding real. The SS amps that for me capture much of this is the Pass XA25 and FW SIT3, i was so impressed with the XA25 that i purchased one 2 months ago".

Very interested if you could ellaborate on diferences between XA25 and SIT3. How are they different between them and how do they differ from your SET experience? BTW, what kind of music do you listen to?

I'm designing an active system around SETs for midrange and treble, but SIT3 and XA25 often make it to the "what if". But haven't heard them.

@lewinskih01, I can’t comment on the sonic differences between the XA25 and SIT3 (I’m a very happy owner of an XA25, but I haven’t heard the SIT3). However a non-sonic difference that may be important in many applications is that the gain of the SIT3 is **very** low for a power amp (spec’d as 11.5 db; measured by Stereophile as 11.3 db). That would make it a non-starter for use in my system, for example, since the DEQX HDP-5 I use as my preamp provides little gain. In fact the 20 db gain of the XA25 (which is about 6 or 7 db less than typical for a power amp) approaches (but does not quite reach) the point of being marginal in my system when I'm playing LPs.

Best regards,
-- Al

The posts caught my attention as I am in the middle of choosing a 211 or 845 amp. You’ve allayed the concerns the posts raised.

@atmasphere Can you comment as well? Thanks.

@david_ten   The bigger the SET, the more issues you have with bandwidth. Some of this depends on design, for example the type of amp known as a 'parafeed' can have more bandwidth since DC is kept out of the core of the output transformer. This is why the 300b for the most part has described the upper limit of 'hifi' since getting more than about 7 or 8 watts means that the audio passband is compromised. If you really want to get the soundstage right, the amp needs to have minimal phase shift in the audio regions so it will need bandwidth past 80KHz. Most larger SETs simply can't do that!


Also if you want to get the bass right, you need bandwidth on the bottom end to prevent phase shift from robbing the amp of that impact. The general rule of thumb is 10x the cutoff frequency so to do 20Hz correctly you have to go to 2Hz. Again, most SETs can do that, many struggle to get down to 20Hz without rolling off!

IOW the larger SETs can be regarded as a tradeoff between bandwidth and power. Now as I've mentioned a fair amount, with SETs that do not run feedback (which is the vast majority of them) you really don't want to run them past about 20-25% of their full power rating in order to really be hearing what they do. This means that you really need an efficient speaker. Higher power SETs try to get around this limitation somehow, but IME this is a forlorn hope. So if you need more power, you are far better off getting a moderately powered push-pull amp. The distortion is lower overall, so you get a greater amount of 'usable' power. I put that in quotes because of course you can run an SET past that power limit I mentioned, what happens is you get more distortion and it starts to sound loud. But that is an interaction with the kind of distortion its making (higher ordered harmonics) and the way our ears perceive sound pressure (it uses higher ordered harmonics to gauge sound pressure). A push-pull amp is less likely to do this.

If you've ever read a comment about how 'dynamic' a certain SET is, that comment derived directly from running the amp on a speaker that was not efficient enough to prevent the user from running above that 20-25% power region. Dynamics are supposed to come from the recording, not the amp!! The word 'dynamics' as used by audiophiles usually means 'distortion' and the latter can replace the former in most audiophile conversation without changing the meaning of the sentence in which the change occurred.


Bottom line: I would think twice about a buying a higher powered SET, if getting the music to sound more real is your goal. OTOH no worries if you just want a nice sounding stereo that sounds loud.

Thanks for the more easily understood, non technical explanation Ralph. One comment that pertains to my exact situation is that when I do crank the volume on my 300B SET it does start to sound loud! I have put in a First Watt M2 amp into my system. Through what I have come to understand and accept is that SS may be more intellectual and SET more visceral. But the detail, bass and overall impact are things to be appreciate and enjoy. However, it is also clear that I am an emotional man, especially when it comes to my hi fi and even the two channel home theater that it doubles. I am forcing myself to continue to listen to the M2 but I don’t know if I will be able to sacrifice the visceral. I believe I could get that with say one of your amps but 38, I think, tubes and very low WAF. Could I get this with a push pull tube amp? Then a BIG SS plus is getting an amp with a lot of power and a lot of head room. I imagine the effortless sound of tons of headroom my be very attractive. Intellectual? Now listening to a great recording of a Telemann chamber orchestra and hearing the inner detail makes it quite enjoyable. I can imagine how additional headroom would add a lot! However, it still does not grab my subjective and emotional senses. Could SS be a more objective and intellectual exercise?

Wow, this is just so typical.
Here your correct, and we probably all agree.

If you really want to get the soundstage right, the amp needs to have minimal phase shift in the audio regions so it will need bandwidth past 80KHz. Most larger SETs simply can’t do that!

Neither can Class-D because of it’s switching frequency and associated output filter to get rid of it, that brings phase shift down into the audio band as this shows in red. https://ibb.co/sjNy1Fq
Over here https://forum.audiogon.com/discussions/gan-based-class-d-power-amps you say the opposite, because you have a Class-D coming out.

Neither can Class-D because of it's switching frequency and associated output filter to get rid of it, that brings phase shift down into the audio band as this shows in red. https://ibb.co/sjNy1Fq

This statement is false in that it ignores entirely self-oscillating amplifiers which are able to correct for phase shift. All the class D amps designed by Bruno Putzeys can do this. Self oscillating amps have been around for over 15 years.

However, it still does not grab my subjective and emotional senses. Could SS be a more objective and intellectual exercise?

You are touching correctly on something about how audio interacts with the brain. The brain has tipping points- in the case of music, its normally processed in the limbic centers. If the brain picks up on something wrong, it will move the processing to the cerebral cortex! Suddenly the music is less involving. IMO/IME, if you want the emotional involvement (and since music is an art form as old as humans themselves, emotional involvement would seem pretty important) then at least for the time being, you're going to have to deal with tubes.

@lewinskih01 The difference between the XA25 and SIT-3 is very hard to put into words but in a nutshell the XA25 has more bass control and weight the overall presentation has a little more authority will a little more defined presentation of the soundstage and instruments. With the SIT-3 there is a sense of tube bloom, both amps have this but it`s more noticeable with the SIT-3. For me it was a give and take what i had always wished a SET could be better at the XA25 brings. Does the XA or SIT-3 sound like a SET amp? With 3D imaging yes but the tube bloom of lets say a 300B tube is not going to be there but you will have traces of that signature and the XA25 and SIT-3 maintain the realism that SET`s are famous for.

Pre-amps have a big impact on how the SIT-3 and XA25 present their sound currently i`m using a LTA as a pre and the combination works really well, i just placed an order with Supratek for a Chardonnay pre, i had heard one of these pre`s about ten years ago and i have never forgotten how great that pre sounded and now they have a gen3 that`s even better from what i have read.

What i listen too is all over the place, classic rock is at the top, then jazz, jam music, progressive rock Porcupine Tree for example then the classics Frank Sinatra ect. and others Sade, Nora Jones and so on.

Hope this helps somewhat.

You are digging your self a big hole Ralph.

@rh67. I look forward to the compare and contrast of the LTA and Supratek with the XA25 once you have it all settled. 

@annika I`m excited to get the Supratek and pair it with the XA25.

There is really little to no evidence for this statement, and considering the lobotomy most speakers do to phase-shift, it is hard to justify some extra margin from the amplifier destroying sound-stage. Sound-stage is based on volume (not phase dependent), ear to ear timing cues (also not phase dependent as long as shift is same for both speakers). That also primarily happens much less than 20KHz.


I don't think I have ever read any experiment that shows the ability to differentiate anything but quite significant phase shifts.

If you really want to get the soundstage right, the amp needs to have minimal phase shift in the audio regions so it will need bandwidth past 80KHz. Most larger SETs simply can't do that!

@rh67
That is helpful,  thank you!
In my context it seems the SIT3 might be the better choice. I'm assembling a 4-way active system and this amp would drive the midrange (300-1800Hz), so the added bass presence from the XA25 wouldn't be developing. Would you agree?
However I drive the amps directly from a SS DAC, so if a SET had enough power it would likely be the preference. 

Good food for thought.
Thank you!

@atmasphere Ralph, thanks for your response to and explanation of my question. For example, one ’higher power output single tube’ amp has Bandwidth listed as 10Hz through 60kHz. Based on what you shared earlier, how much of an impact would you expect minimal phase shift ’issues’ to have on overall sound quality? I did make note of your recommended "best range being 2Hz through 80kHz."

I realize all amps will have trade offs based on design and choices made with respect their build.

Those who disagree with Ralph... are you saying the above is not something I should be concerned about with respect higher output single tube SET amps?

Thank you.

I personally love my CH Precision M1.1 Amplifier. 

Sound-stage is based on volume (not phase dependent), ear to ear timing cues (also not phase dependent as long as shift is same for both speakers). That also primarily happens much less than 20KHz.


I don't think I have ever read any experiment that shows the ability to differentiate anything but quite significant phase shifts.

@roberttdid

This is all true. However there is a reason that wide bandwidth is a sought-after thing going well back (Stewart Hegeman, designer of the original H/K Citation series, felt wide bandwidth to be quite important). That reason is simply while the ear is insensitive to phase in sine waves, triangle waves and the like, it does use phase information for echo location and so does respond to phase information when a spectrum of frequencies are involved. It also interprets phase shift as a tonal coloration; a change in FR one or two octaves outside of the audio passband can be heard as a tonality in the audio band, with little regard for the loudspeakers involved. I had this demonstrated to me in spades about 30 years ago when I was sorting out an MFA Magus preamp in my shop; the complaint was brightness in the phono. It turned out to have an extra timing constant that set the phono EQ to flat at 50KHz. This was clearly audible as a brightness. By simply removing the components responsible in the EQ network, the RIAA slope was restored (at 50KHz) and the brightness removed. When the RIAA curve was tested using an inverse RIAA network, it was perfectly flat up to 20KHz before and **after** the change. I passed this information back to MFA and they incorporated it into their later production of that preamp.


In high end audio we are always concerned about the nth degree; if you really want to get soundstage right, you need wide bandwidth in the electronics even though the speakers won't reproduce it. And we also want the tonality to be correct; especially in an amplifier with a higher output impedance like an SET its going to have FR errors; it will do it no good if it sounds dark on top due to a rolloff above 20KHz.


Alternatively you can employ enough feedback so that the amplifier can compensate for phase shift in the audio passband. But to do that you need north of 60dB of open loop with good Gain Bandwidth Product and good phase margins, since you'll need to blow off 35dB of that gain (if we are talking about a power amp) with feedback.  This is next to impossible with tube amps and very difficult with traditional solid state designs (to my knowledge the Benchmark is one of the very few to do this). The most common amps that employ this much feedback are self-oscillating class D amps (mostly designed by Bruno Putzeys).

For example, one ’higher power output single tube’ amp has Bandwidth listed as 10Hz through 60kHz.

@david_ten 

Almost any power tube has bandwidth from DC to several MHz at least. We have 40MHz bandwidth in the output section of our amps- we intentionally limit the bandwidth in the voltage amplifier. The real issue is the bandwidth of the output transformer (which we haven't got).


The power bandwidth and the low power bandwidth are two different things BTW. I'm of the opinion that they should be nearly the same. But in many amps they are not- its common for the 1 watt bandwidth to be much wider than the full power bandwidth. So it might be a good idea to get some clarity about what is meant by

Bandwidth listed as 10Hz through 60kHz.

@atmasphere  Thank you for the insight. I will look into it.

This has been educational and helpful. Much appreciated. 

Hi everyone

Pass Labs class ‘A’ amps, to my ears, are magic. I have owned the xa30.8 and I just love it. My speakers are extremely inefficient (83db) and it not only drives them effortlessly but it always remains so musical. I have a tube preamp for that tonal color and accurate timbre. 

To all the other Pass Labs amp owners out here, leave it on always. I have noticed that every time I have to unplug it from the wall, it takes exactly 3 full days until it sounds right again. There are subtle temporal cues that you can hear when it’s been fully warmed up that just aren’t 100% right when it’s just been turned back on. I leave mine on all the time and it always sounds amazing!

Scot

@david_ten My best advise is to forget about specs just go listen to the equipment your interested in first. Let your ears be your guide, knowing specs before hand can influence the brain and what you think your hearing.

I have decades of 211-845 amp use, Audio Note Ongako and Kagura 211 amps, Sophia Electric 845 Mono Blocks and LM 845 amps. If you went by specs alone you would never listen to these amps, sound wise they are some of the best sounding bar none. My personal preference are the 211 tubed amps.

@scothurwitz I purchased a Pass XA25 a couple of months ago and i agree there is some magic (voodoo) going on. Once they get past their burn in time the XA25 took 120 hours there is some magic to be had. When i bought mine it had a ten day trial where i could have sent it back and i almost did a couple of times but once it got beyond the 120 hours it has settled down and has been near perfect and this is coming from a SET guy. The Pass is the best SS amp that i have heard and i have tried many including the latest D amps.

I have a Pass XA25, LTA UltraLinear, SIT 3, FW7

The Pass is a very good amp, much preferred to my ears over the SIT3 however I don’t believe that my speakers are the best match for the SIT3 so please take that into consideration (Tannoy Eaton ~ 89db @ 8 ohm). That said, I find the SIT3 too rounded for my taste.

The XA25 gives you phenomenal transients, accurate bass (not heavy), lots of color, great staging & imaging. It presents an incredible amount of detail while sounding relaxed. However in contrast to the LTA UL - it is drier.  The tone color is there, but the juice and body isn’t there to the same extent. You still know it’s a solid state amp in a A/B comp.  

All in though - very highly recommended. It tends to be the main amp in my rig for most music. Prefer the XA25 for jazz, fusion, blues etc., but the UL takes the cake for classical !

If I could combine the UL and the Pass - I’d be done. The Bakoon 13R is on my list, looking forward to the 6moons review of the XA25 INT vs the Bakoon. I’m curious to know if the Bakoon is less "dry" sounding (again relatively speaking) than the XA25.

Valvet is also on the list

@rh67  Thanks for your advice. I've reached out via PM.

ag3__ description on the XA25 is spot on with my experiences. In my system, I use a Cary 805C (845 SET)  and XA25. I switch between the two based upon the music and my mood at the time. Generally, I prefer the Cary.

Sansui go on for almost 50 years in audio and the goal for their last 30 years was reproducing their best tube amplifier sound (1965) in a solid state version(1995), they accomplish that after more than 30 years of continuous research... Name one company in audio that have the same goal for 30 years ? Not an indefinite improvement goal, nor a general one, but a very difficult task and precise one, finally accomplished just before their bankrupcy.....Read that review... this is astounding...

http://www.sansui.us/issues_AU111vsAL907MR.htm

My rightly embedded Sansui is the AU-7700 and gives me great dynamic with organic sound without feeling any lacks in details... I embed it rightfully tough, controlling mechanically for resonance, and electrically for a lower noise in the electrical house grid and in my room controlled acoustics I dont feel at all any lack attributed to S.S. amplifiers in general....I own also one Sansui of the alpha series.....


A reminder: it is way more important to embed rightly any electronic component than even upgrading it, because you will never know his true potential S.Q. without a rightful embeddings in the 3 dimensions : mechanic, electric, and acoustic....

There is no comparison at all between the same amplifier rightly embedded and not rightly embedded....This is true for any amplifier.....Out of the box without treating any embeddings dimension is not the way to use ANY electronic component....

Here is the story between the comparison by Sansui between his best tube amplifier and his best solid state one....

http://www.sansui.us/issues_AU111vsAL907MR.htm

Hi everyone

I to am very interested in hearing the LTA amps. As you all probably know, these are all David Bernings designs implemented by Linear Tube Audio at much more reasonable price points. David Berning is a brilliant designer and engineer who has been granted a patent for his ZOTL design and really thinks outside the box. 

The other name brand that has mentioned in this thread is Valvet. Every time I look at the pictures inside these amps and see the simplicity of the build quality and how few parts are being used I want to hear them. 

Scot

This is actually developing into really good thread.I suspect a lot of the posters here really do have good sounding systems.And I am not talking in the "hi fi" sounding sense.And that is perhaps what is great about SETs.I know that if I am going to listen to a system using a good a SET I know I am likely to hear some great music.Not just some soulless "audiophile " pap.Perhaps another way of rephrasing the original title could be-"If you like SETs what other amplifiers do you also enjoy listening to" .In my case it is the Bakoons.Indeed that is exactly how I would describe them.Which does not mean they sound exactly like a good SET.They don't but they have the musical essence of a really good SET. But I am sure there are others and it is great to hear about them.

I'd like to try a Bakoon against my Valvet/Passxa25/First Watt Sit 1 + 3 etc....problem is they are almost impossible to re-sell due to their lack of a following here in the USA. So its a REAL Gamble investing in one without auditioning. Im going to assume you also cant get a 20+% Discount off the MSRP because of the limited # of dealers. I am sure they sound absolutely wonderful.

Bakoon. The offspring of a baboon and a raccoon? Rocky Rebozo?

David Berning is a brilliant designer and engineer who has been granted a patent for his ZOTL design and really thinks outside the box.

This is the only amplifier with I will replace my 2 Sansui...

I read a lot about....The only new complete transformation of the tube amplifier for the last 50 years it seems.... 

I've got a Pass XA30.5 and a Golden Tube SE40.  I'm rigged to switch between them depending on what I'm listening to.  Both so good, but different.

@riaa_award_collectors_on_facebook 

I’d love to hear that comparison. The NA dealer is offering free shipping and 45d in home demos right now on the Bakoon 13R (perks of being a small amp)

Sometime over the next 6-12 months I’d like to get the Bakoon in and compare vs the XA25 and the LTA UL. What I hope is for it to be a mix of the two. My rudimentary understanding of the circuit leads me to believe that the reduced damping relative to the XA25 might produce a "juicier" sound (more body, air and ), without compromising detail retrieval and those wonderful transients.

How does the Valvet compare to the XA25 and the SIT1/3 ? Assuming it’s the e2se ?