[SET Man]

Hey!

    Might as well go for the Guniness World Records for amp with the lowest THD at a given wattage commercially available

     When I started out interested in Hi-End audio in my mid teens I was fascinated by megawatts amps, giant speakers with many drivers and yes measurement specs. Well, funny that I ended up with 18wpc SET amps and 6" Fostex based Single Driver speaker now

    Anyway, I've never heard any DAC amps, so I'm not in a position to comment if DAC amps with super low THD sound better than my highly distorted ancient tech SET amps. After all we buy audio to listen with our ears and not watching it through a measurement scope. Well, at the end of the day... whatever floats your boat man!

Buddy

[sumoking]

The DAC amps are extremely clean and less distortion can be a really good thing. It's already amazing sounding amp line.  If its now a better sounding amp, it is a good thing for the audio world.

Tommy- Specs aside, can you share if the amp sounds better with this change?

Cheers.

[Shear Bliss VMPS]

Tommy does a extra zero or two matter in this day and age ? I think not. Sounds like a 1970s era rehash of specs & power on big massive receivers wars of the day. What should matter most is tonal quality and the most natural midrange that can be wrought from a Class D design.

I feel there is still room there in this regard to make the entire midrange more natural in human warmth terms. Yes a very tough nut to crack for sure, but one that would give the greatest returns tonally and sound wise. Also shut critics of Class D design UP !!

Your MEGAschino mk2.5 upgrade is stellar and totally awesome sounding. It has a beautiful grip and control of my Tekton Electron SEs. But believe improvements in human vocal warmth would/could reveal a new revolution in your amps and perhaps Class D designs too. Tommy shift your restless energy out of extra zeros which mean absolutely nothing, and make your designs throughout the entire midrange area a little bit more natural sounding. And also saying this, becoming the first to do so perhaps.

Sincerely, Doug West

[RonN5]

Doug,

I agree that the chase for zeros matters less than the chase for tone (and soundstage and realism).

For me, one of the benefits of getting the voices right is eliminating sibilance...which was a big improvement when I switched from the Halo to the 2Cherry.

One of the great things about Tommy's amps is the tone but you will also hear that said about some of the tube amps that have far more distortion....meaning that the chase for zeros won't be an acceptable standard for many. 

Also, it seems pretty common that an amp can have great tone with one pair of speakers but not as good with another pair...and change up the room setting and the tone may improve or lessen again....meaning there is always the aspect of how equipment plays together and how it sounds in a specific room.

Finally, there is the whole issue evolving amplifier technology and how do you find a way to stand out with your product in a way that people are willing to give you a try vs the latest new technology product that is getting a lot of hype?

[Barry]

I recently simulated the circuitry for a new spin on our amp technology....

With very realistic component values and some clever tweaks, I was able to get THD at rated lower down to 0.00002%.  Yes, that’s FOUR zeros.

Interestingly, the original purpose of the changes was to increase damping factor at high frequencies, which these new circuits also do quite well.  The simulations take a long time, some more than an hour for a very particular scenario, so I run them in the background when there’s time.

What amount of THD (or lower) do you believe is “essentially distortion free”?

I’m using cherry amp (bi-amp). Very happy with it.  They present good micro details and very musical.  Whenever I change the components or having new tweaks.  They tell me if it sounds better or worse right away. 

There are amp which make things sounds better.  Cherry amp make good sources sound great, and bad source sound ugly.  I prefer amp presenting the truth instead of hiding or beautifying it.  Only this way we could set up the system to the next level.

Of course, having good measurement does not mean good sound.  There are many other factors to take care of.   As a user for 5 years with continuous fine tuning, I would say cherry amp reference class gear.  They are as musical as your source could deliver.

I’m interested to hear the next gen cherry amp soon.

[Shear Bliss VMPS]

Wanted to re-visit my May 8th post. I hope it did not come across as sounding or appearing as being unhappy! Nothing of the sort here as its just simply the finest amplifier I have ever owned.

We all have our own biases whether it be room size or acoustic damping / defusing panels etc. For instance I have always had a problem with the power band of music around the 1Khz range, before and after. When I mention midrange warmth its in this area I like more recessed and laid back. Different speakers can change this as we know.

Will be rolling my Acoustat 1100s back in soon for hopefully a short listen. Will be bi-wired like my Electron SE are now, same cables etc. Lets see how the precieved difference in DB plays out.

Thanks Tommy for your stellar products!!

[morganc]

Wanted to re-visit my May 8th post. I hope it did not come across as sounding or appearing as being unhappy! Nothing of the sort here as its just simply the finest amplifier I have ever owned.

We all have our own biases whether it be room size or acoustic damping / defusing panels etc. For instance I have always had a problem with the power band of music around the 1Khz range, before and after. When I mention midrange warmth its in this area I like more recessed and laid back. Different speakers can change this as we know.

Will be rolling my Acoustat 1100s back in soon for hopefully a short listen. Will be bi-wired like my Electron SE are now, same cables etc. Lets see how the precieved difference in DB plays out.

Thanks Tommy for your stellar products!!

Nice.  What amp are you running?

[AmpDesigner333]

The DAC amps are extremely clean and less distortion can be a really good thing. It's already amazing sounding amp line.  If its now a better sounding amp, it is a good thing for the audio world.

Tommy- Specs aside, can you share if the amp sounds better with this change?

Cheers.

So far, this result is only from a simulation, but we've come to the point where sim results are very close to real life -- with the right components and layout.

More importantly, the output impedance is close enough to zero that damping factor over 1000 is easily exceeded.  That's where trace, wire, and connector resistance actually make a difference.

Sound quality wise, we've found that you can hear the difference, but more from the way the amp handles transients and arbitrary waveform tracking toward the extremes of current draw.  So much is in the implementation and not the specifications, per se.  Items like power supply rejection ratio and the noise floor shape play a part in what you hear as well.

There's no such thing as a "perfect amplifier", but we're getting closer!

[planet10]

the output impedance is close enough to zero that damping factor over 1000 is easily exceeded.  That's where trace, wire, and connector resistance actually make a difference.

And by the time you put a voice coil in series (not to mention that oft seen first inductor), the real damping factor is somehwere 20-40ish. Why not just specify R_out. Damping is a marketing dept creation to make a small number look big.

There's no such thing as a "perfect amplifier", but we're getting closer!

A step closer would be variable _out so you could dial in the amount of electrical damping applied to the loudspeaker. Too low is only an asset if you have a speaker with an ugly/significantly non-flat speaker impedance. It is possible to overdamp the loudspeaker.

dave

[AmpDesigner333]

And by the time you put a voice coil in series (not to mention that oft seen first inductor), the real damping factor is somehwere 20-40ish. Why not just specify R_out. Damping is a marketing dept creation to make a small number look big.

A step closer would be variable _out so you could dial in the amount of electrical damping applied to the loudspeaker. Too low is only an asset if you have a speaker with an ugly/significantly non-flat speaker impedance. It is possible to overdamp the loudspeaker.

dave

The voice coil is what’s being driven. The source impedance under certain conditions can be calculated with damping factor. I find it hard to be biased against any useful performance measurement regardless of how some companies choose to use it.

A loudspeaker that can be overdamped by lack of drive strength is not my type of loudspeaker.  Truly good designs sound better and better with lower impedance drive.  Low impedance drive also overcomes the reactance of the drivers PLUS crossover.  That’s a circuit that is designed assuming voltage source drive.

[planet10]

I will beg to differ.

dave

[opnly bafld]

I will beg to differ.

dave

+1

[Nsm1979]

+1

I am all for people having a difference of opinion.  I am even more in favor of people having strong convictions.  That’s what makes this forum what it is.

That said, have either of you heard one of Tommy’s Cherry amps?  I own one that I picked up off the preowned market.  So really, no affiliation with DAC. The mono amp I own is easily the best I have owned and possibly the best I have had the pleasure to listen to.  He has come out with quite a few new models since mine came out of his factory. I hope to acquire one of his newer creations in the future.  As for now, I have no desire to look elsewhere for my amplification.

Curious to what you “differ”?

[opnly bafld]

I am all for people having a difference of opinion.  I am even more in favor of people having strong convictions.  That’s what makes this forum what it is.

Curious to what you “differ”?

The same thing as planet10. 

Never experienced a Cherry amp and probably never will, never said anything good or bad about the amps, even defended Tommy a time or two when he was new to the forum.
I just have a different opinion as to what makes a good speaker, matching amplifiers to speakers, and at what point damping factor becomes a non factor.