Let's not forget what this amp is capable of at moderate drive (2.83vrms into 8ohms), i.e., the "First Watt":
For grins, I just measured a highly rated commercial Class AB amp at the same drive level:
I think we can all see which one WILL sound better.
For grins, I just measured a highly rated commercial Class AB amp at the same drive level:
I think we can all see which one WILL sound better.
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I've always been attracted to simple designs. I have always been in the challenge of getting the best of the simplest, given that I live in a field of limitations.
Many times, the limitations have challenged me to maximize those few resources that I have.
I believe, with all my convictions, that the DLH amplifier is a good result of the challenge imposed by these limitations.
Horacio Diego Caminotti
Many times, the limitations have challenged me to maximize those few resources that I have.
I believe, with all my convictions, that the DLH amplifier is a good result of the challenge imposed by these limitations.
Horacio Diego Caminotti
I think in a blind listening test with identical source and good speakers, many people can tell. It may not be obvious at first but amps with dominant H2 and monotonically descending higher orders will always beat an amp with higher 3rd, and odd orders. It's the foot tapping urge you get with a good amp, and less fatigue.
Me, too! I have a much better chance of building it without messing it up! Even on this simple amp, I made a few mistakes but luckily, the amp tolerated it.
Congratulations on a superb result. Now, there is still something with a zero global feedback amp that sounds great to me.
Infinitely grateful for your great support. Without your support, it would not have been the same. I think we can make a good team !!!
Best regards
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Nelson did a survey once, its on his website somewhere. He found 1/3 people preferred dominant 2nd, 1/3 preferred dominant 3rd and the rest didn't care. Or something along thse lines. I've found I like a clean sound most times although I expected to prefer some 2nd order, I was surprised when it didn't seem to be that way.
I added two mounting holes, I turn some parts around, I made it a bit smaller over all the PCB layout
I use print set up at paint chose 50% and print
These type is iron transfer friendly because it is single sided
To X that heatsink at another forum I posted would be waste for these project. Similar amp enclosure with high bias handled easily the Pass Aleph30 24-0-24DC rail voltage my 625VA Plitron transformer got warm. The heatsink temperature about 40 to 45C degree.
I use print set up at paint chose 50% and print
These type is iron transfer friendly because it is single sided
To X that heatsink at another forum I posted would be waste for these project. Similar amp enclosure with high bias handled easily the Pass Aleph30 24-0-24DC rail voltage my 625VA Plitron transformer got warm. The heatsink temperature about 40 to 45C degree.
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Come on Gareth, you can feel with a stick which one sounds better!
let me tell you a story
When I first entered the hobby I read as much as I could. It seemed the secret sauce to good sound was 2nd harmonic and then decreasing higher orders. Our mutual friend Hugh designs his amps with this in mind. I build a few different amps (A, AB, tube, SS) expecting to find this to be the best approach. I didn't find it to be the case, for my ears. I really wanted to prefer a good dose of 2nd harmonic but I found it was suitable only for low volume simple music. I listen to a wide range of music. Of all the amplifiers, the ones' that get the most play time are clean and powerful SS AB amps (not all of them are good). I am still curious about other types of amps and given the following for the Pass amps I expect something of that ilk might suit - my Class A amps have all be bipolar and tube. Mind you, I have a vertical FET amp that could be biassed into class A, the topology is closer to a Krell than the simple approach here. And my JLH69 has not been used, doesn't sound good enough in the form I built it and it could be a platform to explore something similar to the amp in this thread. The journey is never really finished, but I no longer find my best amps a limiting factor. But always tempting to play
let me tell you a story
When I first entered the hobby I read as much as I could. It seemed the secret sauce to good sound was 2nd harmonic and then decreasing higher orders. Our mutual friend Hugh designs his amps with this in mind. I build a few different amps (A, AB, tube, SS) expecting to find this to be the best approach. I didn't find it to be the case, for my ears. I really wanted to prefer a good dose of 2nd harmonic but I found it was suitable only for low volume simple music. I listen to a wide range of music. Of all the amplifiers, the ones' that get the most play time are clean and powerful SS AB amps (not all of them are good). I am still curious about other types of amps and given the following for the Pass amps I expect something of that ilk might suit - my Class A amps have all be bipolar and tube. Mind you, I have a vertical FET amp that could be biassed into class A, the topology is closer to a Krell than the simple approach here. And my JLH69 has not been used, doesn't sound good enough in the form I built it and it could be a platform to explore something similar to the amp in this thread. The journey is never really finished, but I no longer find my best amps a limiting factor. But always tempting to play
I was doing similar.
I designed many amplifier with many design philosophies. H2 dominant, H3 dominant, very low THD in all audio frequency, etc. Some of friends like my H2 dominant amplifier, other like H3 dominant amplifier, and other like very low THD in all audio frequency. Me, I like very low THD in all audio frequency
and when we change volume control, the sound (the character) must be not change (below clipping).But for solid state amplifier, if we make high enough slew rate and it will be like-able
Interesting story, I was always a class AB fan. Probably because all the heat scared me living in a overly hot environment.
Then I built a JLH and another, then increased power and it sounded very good. After living with JLH for a few years, while you were fiddling with the NAIM, I pulled my old class AB out of storage and fired it up.
Suddenly I was overwhelmed by the crisp clean sound that I experienced, an the class A sounded muddled and dead.
Interestingly, I think I get used to how something sounds and a change is as good as a holiday. It demonstrated to me that when I hear something different than I am used to it seems to be more revealing than I remembered.
Then I built a JLH and another, then increased power and it sounded very good. After living with JLH for a few years, while you were fiddling with the NAIM, I pulled my old class AB out of storage and fired it up.
Suddenly I was overwhelmed by the crisp clean sound that I experienced, an the class A sounded muddled and dead.
Interestingly, I think I get used to how something sounds and a change is as good as a holiday. It demonstrated to me that when I hear something different than I am used to it seems to be more revealing than I remembered.
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That reminds me, I have to finish off the Naim. And many other things. The day job along with the kids and the house - it's like having two jobs - leaves me struggling for time.
I am not happy with my JLH, too many old 2N3055s in parallel means huge capacitance. I should dig it out and try it again. If my memory of it is confirmed, I may just change over to the DHL
I am not happy with my JLH, too many old 2N3055s in parallel means huge capacitance. I should dig it out and try it again. If my memory of it is confirmed, I may just change over to the DHL
I'm beginning to think that my ideas of high H2 and monotonic decreasing harmonics may not be the only issue. I have designed amps with vanishing low distortion and high (local) feedback and they sound very, very good.
However, there may be many issues in the design of a good amp. Ignoring the variability of the listener, and some will like Class A, some will like AB, and some will only love SETs, there are thorny problems of spatial information, intermodulation, and low noise. I think choice of parts is important too, and layout may influence things.
Consider the diamond buffer. I built one years ago using adaptive bias on the drivers, and it sounded very, very good. BUT there were lots of odd orders in the FFT, highish THD, and I was horrified with what I saw. Yet it sounded damn fine, WTF??
The DLH is an interesting amplifier. With a quasi, you ideally like to have a symmetric current response from the two outputs, so one goes up, the other goes down, and they track with currents. This is not possible using that topology with bipolar or lateral outputs. One goes up and down much more than the other, and this reduces efficiency and makes it look like a SE amp, not that this is bad.....
I believe that the primary influence on a good sound is the topology. I would not put a percentage on it, this stuff is not yet understood. I do like a singleton, like my NAKSA, but then, the SAKSA has a LTP input stage and it sounds better again. I dunno. What does a nerd do about this stuff? Maybe stump up the huge figures and buy a Chinese SET amp. They sound pretty good and tick most of my boxes.
Hugh
However, there may be many issues in the design of a good amp. Ignoring the variability of the listener, and some will like Class A, some will like AB, and some will only love SETs, there are thorny problems of spatial information, intermodulation, and low noise. I think choice of parts is important too, and layout may influence things.
Consider the diamond buffer. I built one years ago using adaptive bias on the drivers, and it sounded very, very good. BUT there were lots of odd orders in the FFT, highish THD, and I was horrified with what I saw. Yet it sounded damn fine, WTF??
The DLH is an interesting amplifier. With a quasi, you ideally like to have a symmetric current response from the two outputs, so one goes up, the other goes down, and they track with currents. This is not possible using that topology with bipolar or lateral outputs. One goes up and down much more than the other, and this reduces efficiency and makes it look like a SE amp, not that this is bad.....
I believe that the primary influence on a good sound is the topology. I would not put a percentage on it, this stuff is not yet understood. I do like a singleton, like my NAKSA, but then, the SAKSA has a LTP input stage and it sounds better again. I dunno. What does a nerd do about this stuff? Maybe stump up the huge figures and buy a Chinese SET amp. They sound pretty good and tick most of my boxes.
Hugh
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