Topping A90 Discrete Review (Headphone Amp & Preamp)

[zhgutov]

Another thing about the volume control (preamp) of A90D.
The following measured with D90SE, A90D and E1DA via XLR.

This is IMD swept of D90SE + E1DA (20 kHz bandwidth):

This is IMD swept with A90D in the middle, volume 87 vs 99 (20 kHz bandwidth):

This is IMD swept with A90D, volume 87 vs 99 (48 kHz bandwidth):

And the second harmonic difference in THD:

Crosstalk difference (again):

It looks like at least the part of the distortion rise with frequency measured by Amir (and l7audiolab) via XLR comes from the volume control.
Again, not sure if this is possible to hear.

 

[trl]

There might be some differences between ADC's inputs as well, hence a small diff. in the resulted values.

 

[zhgutov]

There might be some differences between ADC's inputs as well, hence a small diff. in the resulted values.

V87L is measured at the same input sensitivity as D90SE, so the IMD graph should be ok.

And this is THD for the digital vs analog volume measured at the same input sensitivity of E1DA:

RMAA takes one channel for each measurement in the case of comparison.
This is not perfectly accurate, but it shows the idea of the difference.
The second harmonic is higher on both channels for V87L.

For the reference, this is THD of D90SE at the same input sensitivity:

The results are repeatable.

 

[julyjol]

Hello friends, I bought the A90D at the end of 2022 and today it finally caused an error, I was listening to music and suddenly crackles and pops were heard and it showed the error "-5" on the screen, I turned it off and turned it back on and now it comes up the error "-4" and it no longer manages to boot. Does anyone have any idea what happened and if there is a solution? greetings

 

[Jimster480]

Hello friends, I bought the A90D at the end of 2022 and today it finally caused an error, I was listening to music and suddenly crackles and pops were heard and it showed the error "-5" on the screen, I turned it off and turned it back on and now it comes up the error "-4" and it no longer manages to boot. Does anyone have any idea what happened and if there is a solution? greetings

Wwo that isn't good, how many hours do you have on it?

 

[Toni Mas]

Hello friends, I bought the A90D at the end of 2022 and today it finally caused an error, I was listening to music and suddenly crackles and pops were heard and it showed the error "-5" on the screen, I turned it off and turned it back on and now it comes up the error "-4" and it no longer manages to boot. Does anyone have any idea what happened and if there is a solution? greetings

Thanks Topping for providing an error code number and thus glad to see that everything is under control...

Though i prefer to stay away from "bootable" audio gear...

 

[Jimster480]

Thanks Topping for providing an error code number and thus glad to see that everything is under control...

Though i prefer to stay away from "bootable" audio gear...

lmao pretty savage

 

[Toni Mas]

lmao pretty savage

These guys must learn that reliability is a MUST at any price point and gear should last for years even if sustainability requiremets are more of a threat than an opportunity for their fast growing businesses...

 

[Jimster480]

These guys must learn that reliability is a MUST at any price point and gear should last for years even if sustainability requiremets are more of a threat than an opportunity for their fast growing businesses...

Yep and so far my Topping products have but it makes me wary to see newer products, especially high end have failures after not that much time.

 

[pseudoid]

There is certain amount of "reliability" you expect even from TP but - like TP - audio hardware is relatively cheap enough to flush... rinse... repeat.
I hope @restorer-john doesn't see this!
I replaced a perfectly working 12y.o. Rotel with a Fosi (no software to tank, no error codes to decipher) and I already know the ...rinse... repeat... cycles may be in the horizon.

 

[restorer-john]

Hello friends, I bought the A90D at the end of 2022 and today it finally caused an error, I was listening to music and suddenly crackles and pops were heard and it showed the error "-5" on the screen, I turned it off and turned it back on and now it comes up the error "-4" and it no longer manages to boot. Does anyone have any idea what happened and if there is a solution? greetings

5 , 4 ...

It's Topping's countdown to BOOM! Put it carefully outside, far away from the house and call the authorities. *kidding*

 

[Rhamnetin]

There is certain amount of "reliability" you expect even from TP but - like TP - audio hardware is relatively cheap enough to flush... rinse... repeat.
I hope @restorer-john doesn't see this!
I replaced a perfectly working 12y.o. Rotel with a Fosi (no software to tank, no error codes to decipher) and I already know the ...rinse... repeat... cycles may be in the horizon.

And if mine fails, I'm going the Schiit route like I did for my DAC after SMSL let me down with their aptly named "SU-X." Schiit and JDS Labs seem to last. I suppose I can use my TP to wipe my Schiit?

 

[pseudoid]

I'm going the Schiit route

Don't forget to bring a paddle for that creek!

 

[Jimster480]

And if mine fails, I'm going the Schiit route like I did for my DAC after SMSL let me down with their aptly named "SU-X." Schiit and JDS Labs seem to last. I suppose I can use my TP to wipe my Schiit?

I wouldn't ever buy any of their products. There are plenty of other brands around which you can try before you end up buying the literal worst brand in the name of Audio.

Don't forget to bring a paddle for that creek!

Exactly. Scum should never be supported.

 

[pseudoid]

I replaced a perfectly working 12y.o. Rotel with a Fosi (no software to tank, no error codes to decipher) and I already know the ...rinse... repeat... cycles may be in the horizon.

Some Much credit should be given to FOSI for this:

 

[trl]

Hello friends, I bought the A90D at the end of 2022 and today it finally caused an error, I was listening to music and suddenly crackles and pops were heard and it showed the error "-5" on the screen, I turned it off and turned it back on and now it comes up the error "-4" and it no longer manages to boot. Does anyone have any idea what happened and if there is a solution? greetings

Sorry to hear that, There's a pic in my teardown explaining briefly these error codes, hope it helps somehow:

You might want to contact Topping, maybe @JohnYang1997 knows a bit more about it. However, do keep us updated.

 

[Toni Mas]

Sorry to hear that, There's a pic in my teardown explaining briefly these error codes, hope it helps somehow:

You might want to contact Topping, maybe @JohnYang1997 knows a bit more about it. However, do keep us updated.

Weird to see that may be the unit is not detective, but only needs the "firmware" upgraded to a bug free new version...

 

[mocenigo]

5 , 4 ...

It's Topping's countdown to BOOM! Put it carefully outside, far away from the house and call the authorities. *kidding*

This is unfair. It is obvious that they do not have sufficient experience or knowledge to deal with power stages, whether this is for power amps or headamps. However, their DACs and Preamps are solid and last long without issues.

 

[Roland68]

This is unfair. It is obvious that they do not have sufficient experience or knowledge to deal with power stages, whether this is for power amps or headamps. However, their DACs and Preamps are solid and last long without issues.

Please don't be angry with me if I say this so directly, but firstly, @restorer-john statement is not unfair, and secondly, you don't seem to be aware of the botched work that the Topping company installs in the devices.
And just to make this clear again, I am actually a Topping fan, especially of Topping's development performance.
But what Topping is doing with customers regarding these cast modules is an absolute and bottomless outrage and completely disrespectful to every buyer.
And although the problem with these cast modules has been known for two years and devices continue to fail as a result, these modules continue to be installed in current and new devices.

I now had 5 failed devices myself and another 11 in my acquaintances and circle of friends.
In the industrial sector, I have over 30 years of experience with cast modules for underwater, aircraft/avionics, chemical, various industrial sectors, etc. Such modules often work for over 10 years under the worst conditions.
But Topping has no idea about this and makes several mistakes when casting the modules, even though this technology has long been a solved problem.
And apart from that, it is absolutely stupid and pointless to forget about electronic circuits or modules in the audio sector. The only purpose is to keep the circuit secret, but precisely because of the failures, almost all circuits of these modules have now been published. Bravo topping, goal achieved!

I will no longer buy devices with these modules and no one in my acquaintances and circle of friends will either.
Because of this alone, Topping sold over 50 fewer devices last year, just to my acquaintances and circle of friends. More was spent on DIY.
As long as Topping continues to do this crap, I will no longer recommend these devices.

 

[julyjol]

Update: After contacting the topping technical service and it must be said that they have been very quick in responding, they recommended that I update the firmware and they sent me a file with the name A90D26, it is curious that on the official website the latest update that There is 2.4, now I have the problem that my Windows computer does not detect the a90, the truth is that it has never detected it even though it is working correctly and it has always shown me the code "-2" on the screen. I don't know if it is the cables or Windows or what do I know, I have tried with usbC-usbC and usbC-usbA cables and on different computers and nothing, I only have to try on MAC. The same thing has happened to someone and they have solved it ? Greetings to the forum