GaNFET vs Purifi

I want to hear your comments between GaNfet and Purifi in terms of sounds. Which one has lower distortion?

I know most class A/B amplifier has DC offtset even at a very low level. Therefore, which one has lower DC offset betwen GaNfet and Purifi?

Thanks!
 
DC offset specs for the Purifi modules are in the datasheet - if there are datasheets for whatever GaN-modules you are interested in then look there as well. Anything under 50-100mV is usually not worth worrying about.

As for the bright sound you hear, what (measurements) make you think that distortion is the cause of that?
 
Last edited:
  • Like
Reactions: starkeyg and yys310
OK, so when you wrote "GANfet" you ment that amp... there isn't just one amp using GAN you know... but now we know. Back to the question... don't VTV publish distortion figures? Purify does.

Apparently they don't... they state: No global feedback - then you can be almost sure that the VTV has at least 10x higher distortion than a Purify amp.

Its probably the same amp modules as this: https://www.audiosciencereview.com/forum/index.php?threads/peachtree-gan400-amplifier-review.42910/
The Peachtree accepts analogue signal but VTV does not. Sounds like it has an A to D stage. Shouldn't we put it into account about distortion issue.
 
Most of the gan amps out there have no post filter feedback and this suffer from load dependent frequency response, an issue resolved by modern class d design decades ago. Until gan fets are implemented in such a manner as to take advantage of their strengths, they are just a marketing ploy presenting a solution for which their isn't a problem. Hypex and Purifi both offer non-gan class d that is greatly superior performance wise.
 
The benefit of GaN amps is that their transistors can switch on and off very fast and cleanly compared to other types.

This allows the chopping frequency go to up even higher than most class D. This lets the filtering and smoothing of the chopped signal to have less of an effect on the audible frequency ranges. I think there are GaN amps that have a switching frequency as high as 800 kHz (highest I've read so far).

I have the PeachTree GAN 1. It's a very nice amp,

I have a Behringer pro sound amp that is class D

And a pair of IcePower 1200.

Of the three, the peachtree is definitely the one with the audiophile signature. That is to say that I hear it the least in the signal chain.

The Ice amps come in 2nd, and the Behringer last.

I also remember some earlier class D from my car stereo days. Some of those sounded horrible. I'd rather have a root canal performed through my ears.

In the future, I definitely have my eyes on either Purifi or Hypex. For every dollar I spend on myself, I have to spend 2 on the fam. Christmas is going to be expensive this year. . .
 
  • Like
Reactions: Tubenstein
I know GaNFET amplifier has gallium nitride FET in there. How doe it compare with traditional FET? Does gallium nitride FET lower distortion and more linear than traditional fet or bipolar transistors?

Does gallium nitride FET sound much smoother than conventional FET or bipolar transistors? Anyway does gallium nitride FET sound bright 😂
 
Tubenstein -

The jist of it is that is switches cleanly and quickly. Those who know their stuff when it comes to fets and all the physical and electrical properties of them would look at the graphs and numbers and say that it's easier to realize the theoretical possibilities of class D with a GaN fet than silicon.

The sound is essentially chopped into tinier pieces so that it is easier to filter out the switching noise. As far as distortion, they aren't particularly better in those numbers than say Hypex or Purifi, but they may have an advantage in that there is reduced phase distortion due to the ability to use gentler filters.

There are a few hifi youtubers out there that review amps by the brand AGD which uses ganfets and seem to think it's the bees knees.

My peachtree is indistinguishable to me from my neurochrome amp in terms of clarity and resolution, although it clearly has more behind it when it comes to power if used on large speakers or trying to play loudly.

Both the peachtree and neurochrome are very, very good although I'd refrain from going into all the vocabulary hifi wizards like to use in descriptions, simply because I cannot really hear a difference in them except when delivering a lot of bass. I think most of this is due to volume, not fidelity.
 
I am curious about the GaNFETs.
There are a couple of different companies building them. AGD on the high end, then you have others... notably Orchard and Peachtree*. I also think Buckeye is supposed to have a model out there too. (IIRC Amir did a review of the Peachtree....)

Now I know that not all GaNFETs are equal along w the other components that make up the Amp.

So I have to ask... what makes the amp worth the price?
Which one would you want?
(e.g. I want the AGD Audions but would probably end up w the Orchard and a linear power supply because it fits my currently non-existent budget better.)