yes less is more if not needed, 3 x extra stages or global feedback.
Why don't you just get a boombox then? By your logic, the less the better- surely an all in one boom box must be the ultimate!
Really? suppose your system looks a bit like this, a "knob twiddlers" delight.
We'll see what happens now with GaN that it has one of the biggest Electronic tech giants owning them
https://www.infineon.com/cms/en/about-infineon/press/press-releases/2023/INFXX202310-014.html
We'll see what happens now with GaN that it has one of the biggest Electronic tech giants owning them
https://www.infineon.com/cms/en/about-infineon/press/press-releases/2023/INFXX202310-014.html
Last edited:
That was the point I was trying to make. No angst about triange wave accuracy, it comes for free as part of the topology. And that to me is part of the beauty of the UcD concept. You use the phase shift of the output filter and in doing so include it in the feedback loop and get fantastic measured performance with a very low component count (as noted in the AES paper). At least to me it is an exceedingly clever solution to the particular problem it is trying to solve.Actually self-oscillating amplifiers still work with a triangle wave.
It's only being created by the self-oscillation itself, not by a separate modulator.
This can also be measured btw.
Which has some advantages, especially in/near clipping behavior (as well as a few disadvantages).
Others may disagree, especially those who find the amount of NFB a 6th order implementation needs. but each to their own...
To bad they never implemented it in an ASIC, like TI did with their TPA and TAS range.That was the point I was trying to make. No angst about triange wave accuracy, it comes for free as part of the topology. And that to me is part of the beauty of the UcD concept. You use the phase shift of the output filter and in doing so include it in the feedback loop and get fantastic measured performance with a very low component count (as noted in the AES paper). At least to me it is an exceedingly clever solution to the particular problem it is trying to solve.
That would have been, winner winner chicken dinner.
(although the DSP really sucks at these TAS chips, omg)
Last edited:
I guess you could say less distortion is more better.The Peachtree has factors more distortion with less stages than the Purifi, Hypex and Orchard. So tell me again, how is less more?
This THD of .00027% (Purifi), comparision to the THD of .002% (Peachtree GaN), is aboslutley meaningless, when speakers your playing into are THD of 1-2% or even more.
I'm the first to believe in good specs to a point, and I listen also, but the "spec feaks" that fist pound the table with this minscule difference of .00027% is better than .002% are just that goggle eyed "SPEC FREAKS". They should stay away with their opinions from recommending any kind of audio product for sound quality. Because they don't listen to music at all, they just look at specs so they can brag about how they won the comparison.
Cheers George
I'm the first to believe in good specs to a point, and I listen also, but the "spec feaks" that fist pound the table with this minscule difference of .00027% is better than .002% are just that goggle eyed "SPEC FREAKS". They should stay away with their opinions from recommending any kind of audio product for sound quality. Because they don't listen to music at all, they just look at specs so they can brag about how they won the comparison.
Cheers George
Last edited:
Believing in good design and engineering, as evidenced by stellar measured performance, and listening to music are not, despite your baseless claim, mutually exclusive. The Peachtree products you are touting are an old, out of date design which by today's standards is flawed- load dependent frequency response is just plain poor design. Add to that the false claims they make regarding their GaN implementation which does nothing to take advantage of the actual benefits of GaN devices and you end up with an overpriced product which under performs in today's market. Your shilling of this train wreck is a sad and confused mess when there are plenty of well designed class d amps with stellar performance available from honest and forthright companies.
You owning shares in what you try to promote here is bad form.
Also, see to that the title is corrected - you by now must have seen that the company that makes the amp state that it is indeed using a class-d output stage. You even posted in the "Class-D" subform - or was it moved by mods?
//
Also, see to that the title is corrected - you by now must have seen that the company that makes the amp state that it is indeed using a class-d output stage. You even posted in the "Class-D" subform - or was it moved by mods?
//
Hi,This THD of .00027% (Purifi), comparision to the THD of .002% (Peachtree GaN)
Do you have a web link for the specification you have stated ?
I checked the Peachtree website and other website reviews for the GaN 1 and there are no specifications for THD. Given the design is zero feedback, then the other GaN amplifiers being zero feedback which have <0.04% THD, are a good indication that the GaN 1 will be the same.
Regards,
Shadders.
Indeed, the reference waveform is not a triangle or sawtooth, thus the equations that follow.Page 4...."When the reference waveform is not a triangle or sawtooth, the modulation becomes nonlinear" ...
http://amorgignitamorem.nl/Audio/HD702/UcD/ucd_aes.pdf
//
If you are not convinced, you can study the schematic page 7. In case of doubt, LTspice is your friend.
The older Peachtree Gan-400 with analog input stages, was .004% you can check on ASR. I was out by .002% not that it matters one iota, and that .002% could be the difference between having analog v digital inputs. And the spec OCD goes on.then the other GaN amplifiers being zero feedback which have <0.04% THD
Cheers George
Hi,
Thanks for the indication for the link.
The GaN400 is no different from any other class D that does not employ a lot of feedback such as Purifi/Hypex, especially at 0.004%.
There does not seem to be a link for the GaN 1 amplifier showing THD figures, except the Peachtree website which states < 0.04% THD for the Carina GaN which has zero feedback.
As such, any THD figure you have provided in reference to the GaN 1 will be null and void.
This is not an OCD issue, it is just that you have repeatedly provided THD figures which have no basis in fact, and Gallium Nitride FETs make no difference.
Regards,
Shadders.
Thanks for the indication for the link.
The GaN400 is no different from any other class D that does not employ a lot of feedback such as Purifi/Hypex, especially at 0.004%.
There does not seem to be a link for the GaN 1 amplifier showing THD figures, except the Peachtree website which states < 0.04% THD for the Carina GaN which has zero feedback.
As such, any THD figure you have provided in reference to the GaN 1 will be null and void.
This is not an OCD issue, it is just that you have repeatedly provided THD figures which have no basis in fact, and Gallium Nitride FETs make no difference.
Regards,
Shadders.
Last edited by a moderator:
Drumbeat pounding a rhythm to the brain - la de da de dee, la de da de daa.And the spec OCD goes on.
Because they get asked for.it is just that you have repeatedly provided THD figures which have no basis in fact
Like I said it matters not one iota if distortions are .002 or .0002 if the speakers you listen to are over 2% or so.
This like I said it's become a specification ocd thing that maters absolutely nothing to what's "listened" too.
Cheers George
HI,Because they get asked for.
Like I said it matters not one iota if distortions are .002 or .0002 if the speakers you listen to are over 2% or so. This like I said, it's become a specification ocd thing that maters absolutly nothing to what's "listened" too.
Your post #1 specifically states :
"5: has impressive low .004% THD, very good for an amp without any feedback!!!,"
You specifically raise the THD as something "very good" when in fact your figures are wrong (should be <0.04%). You now go on to claim that THD specifications are OCD. If they don't matter, don't raise them.
Regards,
Shadders.
- Home
- Amplifiers
- Class D
- Peachtree new GaN-1 all "Digital Amplifier" the future?? (and it's not Class-D)