$100-200 linear power supply

@ericgale 

I am of the school of thought that one would be better off buying a better amplifier than sticking 2 or 3 times the cost in a power supply.

Sure, what amp would that be? It would help if you have heard this amp so you can know what type of sound I am talking about.

This is why:

the 4706 Gaincard offered excellent measured performance. In fact, almost all the measured problems I encountered can be laid at the feet of the Humpty power supply.

In your case that's 24 volts and 4.5 amps.

That is a good point.

@akg_ca

I don’t see the merit in an approach of a new LPS at equal to or double the MSRP price of the amp unit itself. I’d put the $200 toward the cost of a better amp first.

Because from my admittedly one-sided and purely subjective listening, I like the basic sound character of this amp. It gets the first 80% right but lacks the last 20%’s refinement. It has a lively, fun sound that just bounces along to the music. The Fosi Audio V3 300W TPA3255 has the more refined "audiophile" quality sound that most people prefer. For example compare Naim to Arcam.

IME it is easier to tame an amp than put life into a dead one (ie switching to the larger 48vdc vs 24vdc P-S.)

I did try running it in for over 100 hours but sound did not change. So I first tried Talentcell 24vdc / 5 amp output. I was expecting the sonic equivalent of an electric car’s instant full torque power as compared to fuel powered engine. What I got was less dynamics and a more flat sound. The sonic character became more like the Fosi Audio V1.0 - TPA3116 50W x 2.

I also tried the $300 IFI power elite. Dynamics were the same as the stock PS but "glare" was reduced by a haze over the music.

That annoying digital “glare”, or digital “edge”, or “brittleness” is a direct function of the minimalist build quality of the amp’s components themselves, that isn’t going to be magically eliminated.

You may very well be right. I am trying to find out if cleaner input power eliminates the need for better internal amp filtering. The Pro-Ject power box I used with their transport (now departed so can not try it out) reduced just the noise to allow hearing deeper into the music. That is what I am trying to duplicate. Battery and IFI switching PS did not do that.

I can smooth out the sound by using my NOS DAC. But don’t like to fix one error with another one.

@carlsbad2

Digital glare does not exist.

Can you elaborate? To give a corollary, it sounds more like a delta-sigma DAC than NOS.

From the same review:

What is less good are the spikes overlaying the waveform at the signal’s zero-crossing points, which imply inadequate standing bias current in the Gaincard’s output stage. When RD writes about "a hardness or glare in the upper midrange and treble," I do wonder if that correlates with the presence of the high-order harmonics that will result from this behavior. Of course, RD also found that this character dissipated after a very long break-in period.

 

Lab 4706 Gaincard, 1kHz waveform at 22W into 4 ohms (top), distortion and noise waveform with fundamental notched out

@jl35 

What made you decide on the TDA7498 and not something like the V3?