yes but then Hiraga himself uses VAC 300b 30 watts push pull and Hiraga solid state Le Monstre with his, many of his followers use replicas of Monstre and Kaneda (solid state), Misho uses low watt single ended pentodes - 4 and 10watts. And then there are transmitter tubes.
What are the advantages/disadvantages of different amp topologies?
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yes but then Hiraga himself uses VAC 300b 30 watts push pull and Hiraga solid state Le Monstre with his, many of his followers use replicas of Monstre and Kaneda (solid state), Misho uses low watt single ended pentodes - 4 and 10watts. And then there are transmitter tubes.
You have to hear a good class d amp e.g electron audio ion mono amps, tube input stage(e82cc) this amp goes in stealth mode(top plate joke) and let you enjoy the music.
Thumbs up for this sweet amps from croatia.
Thumbs up for this sweet amps from croatia.
Kedar,
You have the most listening experience of anyone I know, do you think the VAC 300b PP or the solid state Monstre or Kaneda copies sound more real-to-life than Mark’s GM70 SET’s?
Something I am trying to answer myself. As mentioned my first two systems now - the Yamamura and the dual FLH Altec - are solid state. But specially done systems, by Be Yamamura himself making a current state amp for a single driver. The other fine tuned by Hiraga. And Misho's is single ended pentode, The Pnoe was with Mayer 46, Leif's is with 300b. Can I generalize from these - I don't know. The Mayer 46 is the your ideal example for the lowest watt tube amp. And then the GM70 is better than Kondo Neiro 2a3 And Audionote empress 2a3, and for me compared to your Ayon, but I have not heard it in these same systems. It is also better than the Silvercore 833c, the Thoress 300b hybrid, and I am sure it will be better than the Shindo 300b when I get to compare it.
Hiraga also has DIY expertise to fine tune his amps and system - the VAC 300b balances out with the crossover he has made for himself - so it is difficult to say how it would fit in to another system.
And then there are tube rolls. It is not easy to come to one conclusion here, with my approach I can shortlist for different different drive requirements and topologies, but can't draw a final conclusion - the low watt amp world is very vast and changes with driver and crossover and no. of ways.
So if I had an Altec, I would keep at home a passive pre, a Mayer 10y, and get over amps like The Hiraga, the GM70, a Mayer amp, a 300b maybe from VAC and Border Patrol. a big powered transmitter from Silvercore 304 TL, and his neohybrid, along with their associated preamps, and try to find the best match. A guy in London has the Misho chain. And to do that compare would have to pre-buy some good tubes to allow the amps to sing at their best with the right combination of the preamp.
I will get more clarity on the Hiraga SS and triodes later this year though for sure.
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he has mk2, he also has Wytech 300b and a partridge transformer made 300b. He has balanced his Altecs with the VAC
Post in thread 'SET amp owners thread'
https://www.whatsbestforum.com/threads/set-amp-owners-thread.27070/post-939577
Then the load on the power tube is higher- pushing it more in the direction of a voltage source (IOW, increasing the damping factor). You get less power, but also less distortion (as long as the OPT isn't a problem).
To your first comment above:
The sound quality at the crossover point (zero crossing) should not be an issue with any PP amp unless it's malfunctioning or the bias is poorly adjusted in some cases. That problem has been well understood for over 70 years and literally isn't a thing. The problems I hear in a lot of PP amps have nothing to do with the zero crossing and everything to do with how they make distortion.
Your second paragraph sounds a lot like what I've been telling people for decades now. However SETs don't put out the same power regardless of speaker impedance- try measuring them sometime and you'll see.
Re.: OTLs: first, its 'Futterman'. And yes, they were a bit unstable, owing to very high feedback. The ones that were less likely to oscillate were those made by Julius himself as he didn't pass along some of his tweaking techniques to his successors (like Harvey Rosenburg). Our OTLs play bass quite nicely if the speaker impedance is benign (8 Ohms or more, what an SET can drive). The reason I recommend the Audiokinesis Swarm sub is to rid the room of standing waves, which is an entirely unrelated issue. My speakers at home are flat to 20 Hz and I used our OTLs on them full range right up to when I replaced them with the class D amps.
I used to own A7s. No worries playing a class D on there. Our's plays nice on that speaker despite the high power on account of low noise and a very nice first Watt. If the volume is up too high even a 30 Watt tube amp will damage that diaphragm; speaking from experience. You might contact John at Classic Audio Loudspeakers to see if he has a replacement diaphragm available- he played the difference between the aluminum and beryllium diaphragms for me at CES 20 years ago and it was pretty impressive. The aluminum breaks up and gets harsh if you play it too loud.
There is opinion and there is fact. I recognize both. I've spent a lot of time in my career trying to sort out why people have certain observations about the various topologies. Turns out you can measure and predict a lot of it (owing to improvements in measurement tech in the last 20 years). This is so true that I've found that if you can duplicate the distortion of a certain amp in another amp, the two will sound the same regardless of the topology. I can tell you that neither the measurement people over at ASR or the subjective camp like to hear that. They both tend to get angry about it. But once you understand that the distortion of the amp is in fact its sonic signature, then life gets easier. I don't know how many designers have done this sort of research but I do know I'm not the only one.
To my (your) first comment above:
From experience only (not an engineer), I have noticed that the more engineering / processing of signal, the less real it sounds. PP splits the signal, amplifying one half in one valve, the other half in another valve, then recombines it. A PP may have more power, even less distortion, but no matter how well it is done, IMHO, music from a PP amplifier doesn't sound as real as a directly heated class A SET amplifier.
My records from the 40's and early 50's are some of the best sounding records I own. Why? I believe it was because there was very little manipulation of the sound during recording (and playback). During early studio recordings, the sound engineer would record to tape samples of the music then listen and adjust microphone placement in the room until the recording levels were just right (all done in digital on a computer these days). Recording several takes then cutting and splicing tape before cutting the final master recording to lacquer was basically it.
There were other tricks that were employed back then that did not mess with the signal either, such as recording to two tapes simultaneously then playing then slightly out of sync while being recorded to another tape. I read that the recording studio built had a large echo chamber built into the floor behind Nat King Cole to add fullness (now "effects" are artificial, and added post performance digitally). I always loved Sun Records, why? Because Sam Phillips, the founder of Sun Records, always used minimalistic recording setups. He knew that the more you messed with the sound, the worse it became.
Today, each member of the band records their bit of a song as a digital file, send it over the WWW to the producer whose sound engineers use to create a Frankenstein creature, bits and parts sewn together, out of tune bits corrected, bits they like amplified, those they don't softened or removed, artificial effects added and then electronically sent (again over the WWW) to the record pressers to mass produce.
And as for "distortion", the elimination of such, it seems to me, being the raison d'être of sound engineers. I remember in the 90's how every music playback system (nearly all from Japan) each competed by advertising lower amounts of "Total Harmonic Distortion". The consumer was led to believe that a Sony stacked system with 0.0001 percent THD would obviously sound better than a competitors system that had only 0.001 percent THD. Meanwhile, Japanese audiophiles were buying up VOT speakers and the flea-powered SET amplifiers from theatres that were being torn down or re-fitted with Dolby Surround Sound speakers and subwoofers as well as the mega-watt transistorised amplifiers required to play such.
Measurements are taken of things that engineers can measure, not of things which they can not. I have never been able to pre-determine which system will sound most real/natural to me by looking at measurements, but I have found that the less one processes music, the more real it sounds. If that is because "distortion" is making me think such, well then let's have the distortion.
Interesting amplifier but not one I've encountered. What sort of price is a pair?
Pity there's no balanced in. What Class D technology is used? With the quoted output, perhaps Purifi Eigentakt - just about the best available. I wonder how it would compare with Atma-Sphere's Class D mono amps that use GaNFETs..
GANFETs 2×200Watt at 8ohm2× 400Watt 4 Ohms RMS as far as I know.
I'm not opening the lid of the amplifier. exsample sound vid
Electron Audio – Made in Croatia
electron-audio.com
I am an engineer if that helps.
Your statement about PP in the first paragraph does not describe how PP works. The signal is never 'split'. Not even sure what that means. What does happen is that the signal is amplified in two phases, each being whole, not half. Its not 'recombined' so much as the opposing phases are applied to a single load such that the current flows back and forth.
Again, if you want to compare PP to SET, you have to start by making sure you've covered the variables. For example most SETs use DHTs, so use DHTs in the PP design! Or insure that it has the same output power as the SET and in either case is built with similar component quality and attention to detail. As far as I know, I'm the only one active here who has ever tried to do that. Its not easy- the output transformer is a variable all its own; the DHT that runs PP is going to make about 4x more power so you have to be careful about making sure both amps play at the same level in comparison. But once you've shut down some of the variables what comes out is that a good PP design will run circles around an SET using the same DHTs. Its easier to make out vocals, there's more bass authority, images in the sound stage are more palpable and so on.
I agree for the most part with the next 4 paragraphs as they apply to recording (which has little to do with amplifier design). When I record, while we have a mix board that's quite capable, I use a set of Western Electric mic preamps which can drive the tape machine directly and so bypass the board entirely. It makes for a better recording IMO.
Regarding the last paragraph, I agree that a simple system can sound better. FWIW, our OTLs only have one stage of gain so have a simpler signal path than you see in SETs. You can have the same involving character without so much distortion. You simply get closer to the music.
I guessed you’re an engineer because you seem to always address measurements, that those measurements mean something is wrong with that amp topology and what engineering gear/additions/cheats will be necessary to improve those measurements.
I am not saying you are purposely ignoring “naturalness of sound” as the ultimate measure of any amplifier topology, I believe that designing amplifiers to sound real/natural is not (and never has been) part of an electrical engineering curriculum. Instead, it seems to me that electrical engineers are sol taught a series of well established methods to manipulate measurements (like negative feedback), in oder to measure better (assuming that such makes an amplifier sound better, yes, but more natural?).
I recently went around to a friend’s house to listen to changes he was making to his system. I must admit that bi-amping his speakers with the 300B SET driving mids and top end while a small Class-D amp. powered the bass sounded better than the 300B alone. The simpler M-7 Kondo phono-pre however, was a huge improvement over his more complicated two-box pre-amplifier and separate high-end phono pre. In light of this I will agree a class D can sound very good (driving bass speakers), but must maintain that well designed simpler circuits will probably sound more real than well designed more complicated circuits.
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Where is the atmosphere on this track? I know this album very well and this sounds very damped/dry without a lot of the space.GANFETs 2×200Watt at 8ohm2× 400Watt 4 Ohms RMS as far as I know.
I'm not opening the lid of the amplifier. exsample sound vid
Electron Audio – Made in Croatia
Have you had any experience with this particular engineer’s amps and pre-amps? I have ( including his class d) and in my opinion they are first and foremost natural sounding (perhaps as opposed to colored sounding — which may be how some experience “natural”).
Not all engineers rely only on measurements... Maybe I should put that a different way:
Some engineers are also audiophiles and care a lot about how things sound. But its a simple fact that no matter what kind of amp you have, you have to take measurements to make sure the amp works. Voltage tests are measurements- if they are off from nominal values you start looking for why, like a bad tube, wiring error or the like... measurements are essential and anyone thinking otherwise is trying to live their life according to a made up story; a myth.
The pragmatic engineer has to do a bit of research to be able to draw a line between what we can hear and what we can measure.
It turns out that in the last 30 years our ability to measure things has dramatically improved! But the understanding of what the measurements are showing us is considerably more rare- even to those doing the measurements.
Here's an example: I don't think anyone would argue that harmonics are what define the individual sound of musical instruments- for example the difference between a trumpet and a clarinet. But the measurement guys get up in a huff when you try to tell them that the distortion of the amplifier is modifying that sound of those instruments and that you can hear that as a change in their tonality.
I'm not one of those; I'm the in-between guy that has sorted out an obvious and simple fact: that the 'sound' of any amp, its 'sonic signature' is exactly two things, the first might be frequency response error but the major aspect being how the amp makes distortion. Further, I understand that when you put a musical signal through an amplifier, the harmonic distortion the amp makes isn't a separate signal that might be so many dB down and perhaps 'not audible' because its masked... because the amp makes distortion it adds harmonics to the musical instruments and thus modifies their tonality.
This is a simple realization and its weird to me that most people haven't figured this out; if they have they certainly are not vocal about it!
If you've heard differences between various tube amps, consider this: the differences between various class D amps is more extreme. Some are so bad they are unlistenable to me, some are boring as it gets (lifeless), some are wimpy and don't play bass and some are outright musical by any metric.
When the viewpoint is myopic, such as a seemingly zealous/religious adherence to only one approach to audio, that's when you get in trouble. For decades, people thought of me as that guy that makes OTLs. No-one expected we would produce our own class D amp since tube guys must not know anything. All I can say to that is if you have an engineering degree, if its to be useful you also have to be pragmatic. The head engineer at HH Scott, Daniel Recklinghausen, once said "If it measures good and sounds bad, -- it is bad. If it sounds good and measures bad, -- you've measured the wrong thing." If you think measurements are unimportant you are missing the truth of this very insightful statement.
“If it measures bad, but sounds good you measured the wrong thing” or perhaps your measurements mean nothing.
Here is something for you to consider:
Back when Mr. Recklinghausen said that the only distortion specs were IMD and THD. IMD means quite a lot since its really audible. But THD not so much- in fact really low THD figures have often been associated with bad sounding amps.
But what they didn't do back then was measure distortion vs frequency, which was unfortunate because there is a strong correlation between the musical nature of an amplifier and its distortion vs frequency curve.
For example, if I have this right you like SETs. It might interest you to know that all zero feedback amplifiers have a ruler flat DvsF curve across the audio band. Its not even right to say its a curve. This is IMO/IME essential to getting an amp to sound musical. To explain to you why that is so gets pretty technical as you have to talk about feedback and Gain Bandwidth Product, and why if those things aren't right the amp can sound messed up. I think I might have covered that already in this thread anyway.
Amps that don't have feedback don't have to worry about Gain Bandwidth Product so how musical they are depends on their distortion spectra. There is a member here who goes by 'morricab' who is an SET aficionado and he harps on how you have to have exponential decay of amplitude of higher ordered harmonics as the order of the harmonic is increased (turns out as long as the decay of higher orders is on an exponential curve, the actual exponent isn't important but that's another topic) in order for the amp to sound right. He's not wrong.
That's clearly a set of measurements!
This being the internet you can say what you want but that does not make it true. Engineering makes all audio (including SETs) possible as well as cars, the internet, airplanes and so on. Its not like you get to pick and choose; measurements are essential in all engineering disciplines.
Measurements are only a guide to an exciting rendition of music that will closely resemble the experience of the live performance.
Do conductors use measurements to judge the performance of their orchestra? No of course they don't!
Do orchestras sound the same when they play in different concert halls? No of course they don't.
But likewise all amps should not sound the same, which in theory, they would if they all measured perfectly. They don't, and neither should they measure perfectly. The best measuring amp I've ever owned happens also to be just about the dullest. A bit a "character" in amps and speakers will make as big a difference to one's enjoyment of the music as choosing the best concert hall with the brightest orchestra, led by the most engaging conductor.
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