Nothing. If the response is flat to 100kHz, harmonic distortion is sufficiently below -75dB at all frequencies, noises and beats of all types are below the hearing threshold, square wave & impulse response reveal virtually no abberations or slewing, and there is no pre or post-ringing, then they will be performing identical. As such, they do sound identical. Beyond that, one may wish to look to ensure that internal components are adaquately chosen.
All properly designed amplifiers perform identical and faithfully reproduce audio waveforms to a degree of accuracy that is beyond human auditory descrimination. Those that induce high distortion belong in two catagories; substandard design and intended distortion. The sole reasons that audiophiles believe that their expensive big name amplifier sounds better or different at all from a HT receiver are entirely the effects of their integral auditory bias system. It's in their heads. An ABX test isolates the biases and will confirm this.
Now, there are several tests that are commonly overlooked by manufacturers, but one of the companies you have mentioned is flatly exempt- Yamaha. They put their designs under serious testing scrutiny, both empirical and subjective. In Tom Nousaine's paper, one of their mid-grade HT receivers was used in an independant ABX test versus a set of $14,000 Pass Labs class A monoblocks, and they were sonically indistinguishable to all those subjects involved in the listening test.
Last edited:
Thanks olafk
I think I can reshape this layout a little bit
can you mark where the jumper wires goes ?
from the top use S2 from Sprint Layout any
color is ok
thank for sharing
Regards
Juan
Attachments
This indicates that you are a rational individual capable of critical reasoning. That is good. KEF's statement is to create a market. The extant fallacy in the speaker marketeer's claim is evident in that they do not attempt to identify what parameter wherein your receiver is supposidly lacking. Power? Only if the amp is being operated near clipping. To their credit, Yamaha designed some of the lowest distortion audio amplifiers ever made, on the order of good opamps today.
Last edited:
soundcheck
Some subjective impressions for comparison.
Sorry Mile, I meant A17 in my last post. I did not built the A23.
A17 and A33 are very similar in my ears. The A33 is highly detailed and a bit more beautiful in bass. But the difference is not great. And I could not run them at the limits.
I have heard compared to the A9. And if I could choose, I would like a amplifier mixed with an A33 and A9. A9 has a touch more of a tube amp. Especially in the bass has a little smoke, more profound, but in a pleasant way.
Can I be understood?
regards Olaf
Some subjective impressions for comparison.
Sorry Mile, I meant A17 in my last post. I did not built the A23.
A17 and A33 are very similar in my ears. The A33 is highly detailed and a bit more beautiful in bass. But the difference is not great. And I could not run them at the limits.
I have heard compared to the A9. And if I could choose, I would like a amplifier mixed with an A33 and A9. A9 has a touch more of a tube amp. Especially in the bass has a little smoke, more profound, but in a pleasant way.
Can I be understood?
regards Olaf
Last edited:
Thanks olafk
I think I can reshape this layout a little bit
can you mark where the jumper wires goes ?
from the top use S2 from Sprint Layout any
color is ok
thank for sharing
Regards
Juan
Did you mean this?
Attachments
Some subjective impressions for comparison.
Sorry Mile, I meant A17 in my last post. I did not built the A23.
A17 and A33 are very similar in my ears. The A33 is highly detailed and a bit more beautiful in bass. But the difference is not great. And I could not run them at the limits.
I have heard compared to the A9. And if I could choose, I would like a amplifier mixed with an A33 and A9. A9 has a touch more of a tube amp. Especially in the bass has a little smoke, more profound, but in a pleasant way.
Can I be understood?
regards Olaf
A9 is my favorite I made similar amps AX9 and C9 and PSU40 for them.
Attachments
You speak of average power that would be half of the max power which is 4.95W. I will research more about this
that's right - half of current does not mean half of power, because power is related in square to a current. for example,1/2 x 1/2 = 1/4...
Yes, I agree.
Might be a good idea, to design a A9 along with PSU as a compact stereo layout. But it would be nice instead of the BC550 to take another transistor, which one could better fit to the heat sink. The layout should be changed - but should not be a problem. Can you prefer one (MJE340)?
regards Olaf
hello sir
about selling PCB sir well .... actually is more in the diy side making them more as personal use to enjoy the build, I order a few PCB of the AX-14T "but .... as personal use" good thing that here in this sections many good people share the layout and with that we have many options to chose from, that make it fascinating
Regards
Juan
about selling PCB sir well .... actually is more in the diy side making them more as personal use to enjoy the build, I order a few PCB of the AX-14T "but .... as personal use" good thing that here in this sections many good people share the layout and with that we have many options to chose from, that make it fascinating
Regards
Juan
I would like to believe that for myself. But trying to be rational, I do not want to be ignorant. Also with so many people spending so much money, I don't want to blindly assume they are all ignorant and subject to hype. So want to keep an open mind.
So if there are people in the audience who have actually compared yamaha, Denon and Onkyo with higher priced amps, I would like to know what they found. It will be really useful to me and thank them in advance.
great job,Olaf and Mile!
i was rude enough to copy your work to our local forum (i also aded direct link to your post there),and i sincerely hope that someone near me will build your pcb of A33 so than we could compare A23 with A33.
thank you so much for effort you invested in drawing visually simple PCB,and for testing it. great job for all DIY comunity,greetings for Mile and you Olaf! great job...
i was rude enough to copy your work to our local forum (i also aded direct link to your post there),and i sincerely hope that someone near me will build your pcb of A33 so than we could compare A23 with A33.
thank you so much for effort you invested in drawing visually simple PCB,and for testing it. great job for all DIY comunity,greetings for Mile and you Olaf! great job...
You should start your own thread with these questions. This thread is about Apex amps which are DIY. You will get far more folks looking at your questions.
