Topping A90 Discrete Review (Headphone Amp & Preamp)

[808lab]

I'm getting the exact same error. My A90 Discrete amplifier stopped working and all I get to see is error -5. Did you end up figuring out what caused the issue ?

Which dac you use?

 

[madani]

Which dac you use?

I've connected A90 Discrete to a D90SE. I spent hours today to figure out a way to fix the issue. Here are the steps that I took that finally fixed the issue for me. I'm not sure what this error message means or why it appeared or why it's not appearing again, but my A90 Discrete started working again after following these steps

1. Unplug from everything (DAC, power, headphone)
2. Wait for 5 minutes
3. Plug the power back in
4. Turn the amplifier on
5. I got error -5
6. I left it on for more than 10 minutes (I forgot about it after spending hours trying to diagnose the problem)
7. The -5 error disappeared on its own!

 

[tomelex]

I've connected A90 Discrete to a D90SE. I spent hours today to figure out a way to fix the issue. Here are the steps that I took that finally fixed the issue for me. I'm not sure what this error message means or why it appeared or why it's not appearing again, but my A90 Discrete started working again after following these steps

1. Unplug from everything (DAC, power, headphone)
2. Wait for 5 minutes
3. Plug the power back in
4. Turn the amplifier on
5. I got error -5
6. I left it on for more than 10 minutes (I forgot about it after spending hours trying to diagnose the problem)
7. The -5 error disappeared on its own!

That is not good in the long term.

 

[escalibur]

I've connected A90 Discrete to a D90SE. I spent hours today to figure out a way to fix the issue. Here are the steps that I took that finally fixed the issue for me. I'm not sure what this error message means or why it appeared or why it's not appearing again, but my A90 Discrete started working again after following these steps

1. Unplug from everything (DAC, power, headphone)
2. Wait for 5 minutes
3. Plug the power back in
4. Turn the amplifier on
5. I got error -5
6. I left it on for more than 10 minutes (I forgot about it after spending hours trying to diagnose the problem)
7. The -5 error disappeared on its own!

How common this issue is nowadays? I'm planning to upgrade my A90 to A90D but this issue makes me thinking will I be forced to RMA my unit to whatever place the used unit might be bought from.

 

[SiamXIII]

You can't imagine how I moved from night to day today... I was able to return my Stealth + DAC + both Amps.
And now I can't stop being awed song after song.

To make it shine my advice is :
- Windows volume doesn't matter (it's ignored)
- SMSL DAC USB Driver on windows
- selected windows device : SMSL USB DAC
- foobar output : primary sound driver
- foobar volume @ 0db (max)
- SU-9 Pro @ -6db to remove RCA & DSP distorsions
- A90D (button B) in either Volume Curve 1 or 2 with High gain
- A90D custom C1 for headphone only, custom C2 for loudspeakers only
- LA90 AB @ 50% volume

Tears are close!

@amirm Thanks for the tests. Helped a lot to narrow flagship hardware for a bargain!
Got my whole setup for about 6000€ during chinese black friday (excluding my loudspeakers).

What is difference with SMLS DAC>A90D>LA90 vs SMSL DAC>LA90?

Currently have SMSL D300>LA90 and thinking about preamp.

 

[metasharp]

LA90 is a speakers amp. A90D is a headphone amp. it is in passthrouh when plugged on the la90 regarding speakers so no difference with or without

 

[SiamXIII]

LA90 is a speakers amp. A90D is a headphone amp. it is in passthrouh when plugged on the la90 regarding speakers so no difference with or without

A90D is also preamp with analog volume control vs digital volume control in SMSL DAC. Have you tried to set DAC in fixed vol mode and control volume on A90D?

 

[metasharp]

don't do it or say hello to distorsion.

 

[SiamXIII]

don't do it or say hello to distorsion.

What will cause it?

 

[metasharp]

to remove audible distorsion i had to set the volume (variable mode) of the dac to -4db for xlr outputs or -6 or -7db for rca outputs.

it's easy to test by activating the dsp effects such as clear 1, 2 or 3 on the dac. The sound starts to pchhhrrrrrrrr loudly if not using the above setting to lower the volume.

 

[SiamXIII]

to remove audible distorsion i had to set the volume (variable mode) of the dac to -4db for xlr outputs or -6 or -7db for rca outputs.

it's easy to test by activating the dsp effects such as clear 1, 2 or 3 on the dac. The sound starts to pchhhrrrrrrrr loudly if not using the above setting to lower the volume.

It's strange. Had no issues on SMSL D300 in fixed mode.

 

[metasharp]

fixed sets the volume to 0

 

[SiamXIII]

fixed sets the volume to 0

And at fixed it sounds way better and less compressed, than at 70/100.

 

[metasharp]

what is 70/100??

 

[SiamXIII]

what is 70/100??

Volume is set on 70 out if 99 in variable vol mode.

 

[808lab]

Volume is set on 70 out if 99 in variable vol mode.

Can you explain it more deeply?
I’m waiting for my a90d+d90le stack that I’ve bought

 

[metasharp]

UPDATE

To make it shine my advice is :
- Windows volume doesn't matter (it's ignored)
- SMSL DAC USB Driver on windows
- selected windows device : SMSL USB DAC
- foobar output : USB DAC ASIO (to make sure the DAC receives native bits/KHz)
- foobar volume @ 0db (max)
- SU-9 Pro @ -4db to remove XLR/DSP distorsions or -7db to remove RCA/DSP distorsions (to test, listen a music and activate Sound mode "Rich 1", if you hear pchrrrrrrrrrrrr, lower the DAC volume)
- SU-9 Pro in PRE mode "Fixed" (unlike what's said in the manual, it doesn't forces the volume to 0db, it actually freezes the volume at the chosen value of variable mode)
- A90D (button B) in either Volume Curve 1 or 2 with High gain
- A90D custom C1 for headphone only, custom C2 for loudspeakers only
- LA90 AB @ 50% volume

 

[leonidas]

I‘ve ran into multiple reviews of the A90D lately on YouTube where the reviewer critiziced the A90D for being „too perfect“. They say it is only built around measurements.

At the end of those videos they claim you essentially need a certain degree of distortion to even make the music enjoyable and how better amps sound which measure worse. They even claim those „worse“ amps are so much better and they even deliver better soundstage, more details, better bass etc…

Is this all the classic audiophile esoteric nonsense or do they have a point?

 

[Purité Audio]

The former.
Keith

 

[Grobbelboy]

Hah, purely coincidentally I just skimmed through this video which fits that description very well. I just had to stop watching after the umpteenth silly subjective claim.

Once again the idea that you just can’t expect something great when you don’t spend thousands of dollars, like the reviewer of course has done, is pushed to the front constantly. The anecdotal reputation of Topping’s offerings blowing up headphones is also wheeled out in the conclusion.