Maybe its mostly used in RF amplifiers...
https://www.chalmers.se/en/centres/...for_the_linearization_of_power_amplifiers.pdf
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Hi Chris,
I would agree with your statement "fix the problems where they exist with the appropriate tools".
Now the problem is to define a boundary for the problems that should be solved as a result of the measurements.
Assuming Cyrus engineers own the suitable tools, is there a problem to fix in the Mono X amp?
From the published data it would seem so, as the measurements are anything but spectacular when compared to the NC400.
So I wonder why they didn't fix the problem since they just would need to add tons of global feedback to fix it.
Or there is nothing to fix, it depends on the used boundary.
Andrea
I would agree with your statement "fix the problems where they exist with the appropriate tools".
Now the problem is to define a boundary for the problems that should be solved as a result of the measurements.
Assuming Cyrus engineers own the suitable tools, is there a problem to fix in the Mono X amp?
From the published data it would seem so, as the measurements are anything but spectacular when compared to the NC400.
So I wonder why they didn't fix the problem since they just would need to add tons of global feedback to fix it.
Or there is nothing to fix, it depends on the used boundary.
Andrea
I don't want to name names, but I will say they tend to have what makes sense for them. For example, some only do analog audio design. They don't do dacs, so they don't need gear that is spec'ed to be really good for some aspects of data converters.
Have one here. May sell it. The modified Aragon 8008 MkII drives the Sound Lab electrostats better, and IMHO it loses less of low level details too.
Andrea, zero feedback class-B amps sound different (Class-B is the output stage of the current buffer). It is not "fluent". They have strength in dynamic and unique character in the bass region, almost similar to class-D amplifiers.
Agreed. IME accepting a little not-too-bad distortion may be the price one has to pay to improve other device characteristics. Its a trade off to get more realistic sound. IMHO its not so much about people liking more distortion; that seems a red herring (distracting) hypothesis.
Thank you Matt.
@TNT
Thank you, I'm far from that level of expertise. Just extending basic stuff known to work in single driver systems into multi amp system, allows me to use lower distortion drivers. Never expect it to be perfect, just a technique I can try to reduce system THD for I have no knowledge of other alternatives. From an ABX tone test made available by PMA, I know I can hear 0.9% H2 @300, 1k & 3kHz therefore I have been looking for ways to reduce the final acoustic distortion. Perhaps I won't live to see the end of the road but I enjoy the journey anyway.
@TNT
Thank you, I'm far from that level of expertise. Just extending basic stuff known to work in single driver systems into multi amp system, allows me to use lower distortion drivers. Never expect it to be perfect, just a technique I can try to reduce system THD for I have no knowledge of other alternatives. From an ABX tone test made available by PMA, I know I can hear 0.9% H2 @300, 1k & 3kHz therefore I have been looking for ways to reduce the final acoustic distortion. Perhaps I won't live to see the end of the road but I enjoy the journey anyway.
Would it not be possible that those saying that speak their own preference? They seem to champion lowest THD amps which tend to preserve the distortion of the speakers pristine as can be.
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Hi Andrea,
The design of the Mono X is based on diamond buffers. They do not require local feedback, but my designs in the same area use a diamond buffer within the feedback network of a standard gain stage. In that configuration there is less distortion and performance can be higher than a normal darlington, common emitter output stage. They are also very fast. It's just another way to build an amplifier and I am exploring this type of design as it looks promising.
Other examples of this include earlier Nakamchi amplifiers like the 620, and the Marantz 170DC and 300DC. There are others, and I like the sound of them, especially after I improve them. The Mono X is different in that there isn't any feedback used. The performance is quite good considering there isn't any feedback.
They don't really have any problems to fix given that the design is centered on the premise that there isn't any feedback. I just want to prove that I can't improve them since I own them. I have very little equipment that I have not been able to improve. One such device is my ReVox B261 tuner. I did have to align it when i got it. Someone else had messed with it so badly it took almost two days to bring it back into alignment. Parts had been changed and that needed to be corrected as well. The B261 is one of the best tuners out there. My only real issue are the darned 36 volt meter lamps. Mine just burned out, so I'll be using LEDs and designing a circuit to drive them as the replacement LEDs are 12 V strips.
-Chris
The design of the Mono X is based on diamond buffers. They do not require local feedback, but my designs in the same area use a diamond buffer within the feedback network of a standard gain stage. In that configuration there is less distortion and performance can be higher than a normal darlington, common emitter output stage. They are also very fast. It's just another way to build an amplifier and I am exploring this type of design as it looks promising.
Other examples of this include earlier Nakamchi amplifiers like the 620, and the Marantz 170DC and 300DC. There are others, and I like the sound of them, especially after I improve them. The Mono X is different in that there isn't any feedback used. The performance is quite good considering there isn't any feedback.
They don't really have any problems to fix given that the design is centered on the premise that there isn't any feedback. I just want to prove that I can't improve them since I own them. I have very little equipment that I have not been able to improve. One such device is my ReVox B261 tuner. I did have to align it when i got it. Someone else had messed with it so badly it took almost two days to bring it back into alignment. Parts had been changed and that needed to be corrected as well. The B261 is one of the best tuners out there. My only real issue are the darned 36 volt meter lamps. Mine just burned out, so I'll be using LEDs and designing a circuit to drive them as the replacement LEDs are 12 V strips.
-Chris
Isn't that largely because they don't have the same listening experiences?
If anyone listened to my friend's system, they would be impressed with how realistic a system can be. One visiting Japanese audio consultant and reviewer said it was one of the best few systems in the world that he had ever listened to. Unfortunately it is very costly to do at that level, and it takes expertise to know how to design it and put it together. Even then, it is not perfect; the way the overall system departs from reality is above the threshold of audibility (including the audible imperfections of recordings that the system reveals).
The lesson for me was that maybe there is a path to optimal realism, but there are many more false paths that lead to some relative optimum, or else to wasted money.
Now I should answer as others repeat over and over: can you prove it?
can you share what you heard over the internet?
Instead I leave this answer to the clever people who write on this thread.
On the other hand I am a poor hobbyist rather than a smart audio designer.
Hi Mark,
That is very true.
All you can do is put together a system that you can live with and enjoy. Luckily, we here can build and use the advice of various experts. There are even some mighty good kits available as group buys or in the store. They might not be the very best, but are often significantly better than what you can buy at reasonable money.
Knowledge is key, and here you are surrounded by countless knowledgeable individuals willing to help. Yes we have complete flakes as well, but you can usually sort through people.
-Chris
That is very true.
All you can do is put together a system that you can live with and enjoy. Luckily, we here can build and use the advice of various experts. There are even some mighty good kits available as group buys or in the store. They might not be the very best, but are often significantly better than what you can buy at reasonable money.
Knowledge is key, and here you are surrounded by countless knowledgeable individuals willing to help. Yes we have complete flakes as well, but you can usually sort through people.
-Chris
Hi Andrea,
I guess my previous post might apply to you as well.
The proof is in careful measurements and proper interpretation of them. If something "looks" terrible, it likely doesn't sound very good when compared to things that are very good. The only things we can transmit is a written description of what we hear, and measurements.
-Chris
I guess my previous post might apply to you as well.
The proof is in careful measurements and proper interpretation of them. If something "looks" terrible, it likely doesn't sound very good when compared to things that are very good. The only things we can transmit is a written description of what we hear, and measurements.
-Chris
Well, if you are curious, ask Chris to record the sound of zero-feedback class-B amp and another one from "normal" amp 9not class-D). I will tell you which is which.
If you have good ears and at least have built a thousand amplifiers, you might be familiar with amplifier sounds. Here is attached a typical current buffer that I have worked with and am familiar with.
Replace the class-B current buffer with Pass Labs F4 and I believe you will like it better. Have you built the F4?
Attachments
You keep saying that - but most of us see you as a business man. Isn't that strange?
In apost above you just said you had unlimited development budget - can't you at least try to keep a coherent story - it is quite distressing to see you dig yourself into a deep logical cul-du-sac...
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You keep saying that - but most of us see you as a business man. Isn't that strange?
In apost above you just said you had unlimited development budget - can't you at least try to keep a coherent story - it is quite distressing to see you dig yourself into a deep logical cul-du-sac...
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I have personally explained this to you several times but obviously your logic fails.
My business is IT, and just because audio devices are an hobby for me and my friend we have no budget limit.
If the goal was business I would have to deal with a budget imposed by marketing because in the end the products would have to be sold to survive.
Instead IT pays the bill, so I can afford to spend 5 USD and more for a 0.001% resistor.
And if you are so smart as you claim (I'm not very sure) you can imagin how many resistors I need to build a 24 bit segmented sign magnitude discrete DAC.
But since I build it for myself I don't need to worry about the logic of the market.
I think I'll retire before you understand it.
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