• Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Topping A90 Headphone Amplifier Review

I just got a topping a90 and it works perfectly swell. my only issue is i hear a slight high pitched whine on the unit (without headphones just listening to it with my ear near the front panel). Should i be worried? Funnily enough my d10balanced also has a whine which i hope i can fix with a usb power isolator.

probably the power supply or some capacitor that you hear . I also hear that type of noise from laptops, routers , phone chargers etc when I get close to them.
 
probably the power supply or some capacitor that you hear . I also hear that type of noise from laptops, routers , phone chargers etc when I get close to them.
normal for these types of electronics right? though this is the first time ive ever heard it in an amp hahaha
 
I have my original A90 for a few years already. I use almost all interfaces on it. I followed the ground noise discussion and knew what about it from John in this thread.
Since I was using active near field monitors and Fostex T60RP planar headphones most of the time, it wasn't an issue which bothered me that much.
Recently I'm using high sensitivity IEMs by purpose. I can't bear the noise. I would like to see how I could have both RCA and XLR inputs with minimised noise from the RCA.
I'm using my system in Germany with the dual grounded pins socket. Here is my system and set-up.

PC(USB) -> Gustard X16 MQA DAC -> A90 XLR inputs
LED monitor 3.5mm phone out -> A90 RCA inputs <- Source of the ground noise!
A90 XLR outputs -> Adam Audio T5V near field monitors


I need the RCA inputs to let my HDMI monitor to output audio signal to A90, so that I can use A90 for headphones or audio monitors.
The source of the ground noise is rather obvious. I don't have ground noise once I disconnect the RCA connection from A90. Noise has gone.
I have tried to use a JDS Atom(external power adapter) as an intermediate device in-between HDMI monitor and A90. The noise was still there. When Atom is connected to A90 through RCA with a battery powered MP3 player, the noise doesn't exist.

Is there anything which I could do on my HDMI monitor or the RCA cable for the phone out?
 
hi i have a90 and d90 og version combo... but still wonder if i have a chance to upgrade, what product should i get?

and for a90 volume knob, what percentage usually we use?
 
hi i have a90 and d90 og version combo... but still wonder if i have a chance to upgrade, what product should i get?

and for a90 volume knob, what percentage usually we use?
I’d consider the d90 a90 combo endgame…an upgrade would be an atmos 11 channel avr lol
 
hi i have a90 and d90 og version combo... but still wonder if i have a chance to upgrade, what product should i get?

and for a90 volume knob, what percentage usually we use?

If both work and have all the features you need, then none. Upgrade your headphones..
 
I have my original A90 for a few years already. I use almost all interfaces on it. I followed the ground noise discussion and knew what about it from John in this thread.
Since I was using active near field monitors and Fostex T60RP planar headphones most of the time, it wasn't an issue which bothered me that much.
Recently I'm using high sensitivity IEMs by purpose. I can't bear the noise. I would like to see how I could have both RCA and XLR inputs with minimised noise from the RCA.
I'm using my system in Germany with the dual grounded pins socket. Here is my system and set-up.

PC(USB) -> Gustard X16 MQA DAC -> A90 XLR inputs
LED monitor 3.5mm phone out -> A90 RCA inputs <- Source of the ground noise!
A90 XLR outputs -> Adam Audio T5V near field monitors


I need the RCA inputs to let my HDMI monitor to output audio signal to A90, so that I can use A90 for headphones or audio monitors.
The source of the ground noise is rather obvious. I don't have ground noise once I disconnect the RCA connection from A90. Noise has gone.
I have tried to use a JDS Atom(external power adapter) as an intermediate device in-between HDMI monitor and A90. The noise was still there. When Atom is connected to A90 through RCA with a battery powered MP3 player, the noise doesn't exist.

Is there anything which I could do on my HDMI monitor or the RCA cable for the phone out?
Use an hdmi audio extractor to get spdif optical and then a cheap spdif in dac like topping or smsl etc.
 
oh okee, so no need upgrade to d90 3d for example? or d900 ? hahaha

now i use senheiser hd 800..

Exactly! By upgrading a transparent DAC and amp to another transparent transparent DAC and amp you are setting yourself for disappointment if your expectation is better sound.

Did you EQ your HD800? That will have a real impact on sound.
 
Exactly! By upgrading a transparent DAC and amp to another transparent transparent DAC and amp you are setting yourself for disappointment if your expectation is better sound.

Did you EQ your HD800? That will have a real impact on sound.
oh damn, i think it will increase the better sound :"

nope, do you have some recomendation eq for hd800?
 
oh damn, i think it will increase the better sound :"

nope, do you have some recomendation eq for hd800?

Equilizer APO with Peace GUI if on Windows. It's free, and tutorials on YouTube are available to help you set it up.
HD800 EQ:

Edit: Here is the link to all Oratory1990 EQs:
 
Last edited:
Equilizer APO with Peace GUI if on Windows. It's free, and tutorials on YouTube are available to help you set it up.
HD800 EQ:
sorry little confused, i use oratory in apo peace autoeq, why oratory on there is different than on reddit?
which one should i use?

standard vs optimum hifi curve which one should i get?
 
Last edited:
sorry little confused, i use oratory in apo peace autoeq, why oratory on there is different than on reddit?
which one should i use?

standard vs optimum hifi curve which one should i get?
The Oratory PDFs EQs are made manually by him.

The ones in AutoEQ are not made by him but generated by the AutoEQ software from his measurements.

It depends on the specifics but I have generally found his to be better. I think the AutoEQ defaults are better than they used be, they used have a number of issues like making very sharp and specific EQ adjustment to unreliable treble measurements and EQing not to Harman but to their own target (a bass-reduced version of Harman). I know a newer version of the software introduced low and high shelves and I think they also switched to Harman from their own curve. So possibly they are a lot closer now. But I'd still use Oratory1990's own PDFs EQs which are listened to by Oratory. The AutoEQ process is entirely automated and it can be more of a starting point.
 
The Oratory PDFs EQs are made manually by him.

The ones in AutoEQ are not made by him but generated by the AutoEQ software from his measurements.

It depends on the specifics but I have generally found his to be better. I think the AutoEQ defaults are better than they used be, they used have a number of issues like making very sharp and specific EQ adjustment to unreliable treble measurements and EQing not to Harman but to their own target (a bass-reduced version of Harman). I know a newer version of the software introduced low and high shelves and I think they also switched to Harman from their own curve. So possibly they are a lot closer now. But I'd still use Oratory1990's own PDFs EQs which are listened to by Oratory. The AutoEQ process is entirely automated and it can be more of a starting point.
ohh coooll,, oke i will input manually based on the oratory pdff..

herman standard vs optimum hifi curved, which one should i use?

last question..
on band 1, band 2, and band 9, if i choose the filter first (low/high self), why i cannot change the Q-factor?

should i input qfactor first than put the filter later?

Thank you all <3
 
@fendy323 the Optimium Hifi curve is a headphone version of B&K's 1974 Optimum Hifi curve. It is effectively Harman with less bass. Which you would pick would depend on your bass preference (or, you could just lower the bass shelf on the Harman one).

There is an option on AutoEQ to have a shelf with adjustable Q, it's the shelf with the little number on it. Having said that I think the default Q is close enough so it doesn't really matter.
 
@fendy323 the Optimium Hifi curve is a headphone version of B&K's 1974 Optimum Hifi curve. It is effectively Harman with less bass. Which you would pick would depend on your bass preference (or, you could just lower the bass shelf on the Harman one).

There is an option on AutoEQ to have a shelf with adjustable Q, it's the shelf with the little number on it. Having said that I think the default Q is close enough so it doesn't really matter.
hii i try follow oratory pdf
harman =

hifi =

try both pdf, but i notice that hifi sound is louder than harman, is it normal? if normal, so i just need to decrease my music volume?

bytheway, on A90 volume knob, how many percentage usually do you use?
 
hii i try follow oratory pdf
harman =

hifi =

try both pdf, but i notice that hifi sound is louder than harman, is it normal? if normal, so i just need to decrease my music volume?

bytheway, on A90 volume knob, how many percentage usually do you use?

Yes, that is normal. Harman EQ needs -7,5dB attenuation not to clip the bass, while the Optimum doesn't.
My advice is to forget about the Optimum curve and just tune the Harman according to your preference. Adjust the band like Oratory said here:

1754417388162.png


If you want to use both, just attenuate Optimum until it sounds similarly loud to Harman in EQ APO.

1754417553068.png
 
Yes, that is normal. Harman EQ needs -7,5dB attenuation not to clip the bass, while the Optimum doesn't.
My advice is to forget about the Optimum curve and just tune the Harman according to your preference. Adjust the band like Oratory said here:

View attachment 467879

If you want to use both, just attenuate Optimum until it sounds similarly loud to Harman in EQ APO.

View attachment 467881


here my harman settings based on oratory PDF, help me to check it, please? ,

On filters low and high (band 1, 2, 9) i must input Q first before put the filters or i cannot change the Q, is it normal?

I'm afraid of making mistakes. and thank you so much <3
Screenshot 2025-08-06 020434.png



this for hifi
Screenshot 2025-08-06 020538.png


for both is it correct?
 

Attachments

  • Screenshot 2025-08-06 014213.png
    Screenshot 2025-08-06 014213.png
    47.8 KB · Views: 51
Last edited:
here my harman settings based on oratory PDF, help me to check it, please? ,

On filters low and high (band 1, 2, 9) i must input Q first before put the filters or i cannot change the Q, is it normal?

I'm afraid of making mistakes. and thank you so much <3
View attachment 467887

Everything’s fine with your EQ. Now you can play around with bands 2, 3, 5, and 9 to fine-tune the sound. For example, I lowered my HD800s to a 1 dB gain on the 2nd band. The bass didn’t sound right with a 4.5 dB boost.

Since the preamp is set to -7.5 dB, you’ll need to turn up the volume compared to before, when you didn’t have it. That’s completely normal when applying negative gain. The A90 has plenty of headroom, so that won’t be an issue. Just be careful not to accidentally turn off the preamp while listening at high volumes - it will get LOUDER.

Basically, whenever you adjust anything in the EQ APO/Peace, make sure to lower the volume or pause the music first! Make your changes, save them, and only then start listening again. I can’t tell you how many times I meant to enter 2.3 dB but accidentally typed 23 dB… so yeah, use common sense.

If you want to compare the sound with Harman EQ versus no EQ, you’ll need to create a new EQ profile that’s completely flat, but with a -5 dB or -6 dB preamp adjustment. This will match the SPL (volume) level to your Harman EQ profile. That way, you can toggle between them and hear the differences while keeping things roughly level-matched.

Once you get the hang of it, it’s a piece of cake. By the way, how did you like the change with the EQ?

For bands 1, 2 and 9, you can use highlighted filters to set the slope.

1754420255553.png
 
Since the preamp is set to -7.5 dB, you’ll need to turn up the volume compared to before, when you didn’t have it. That’s completely normal when applying negative gain. The A90 has plenty of headroom, so that won’t be an issue. Just be careful not to accidentally turn off the preamp while listening at high volumes - it will get LOUDER.

Basically, whenever you adjust anything in the EQ APO/Peace, make sure to lower the volume or pause the music first! Make your changes, save them, and only then start listening again. I can’t tell you how many times I meant to enter 2.3 dB but accidentally typed 23 dB… so yeah, use common sense.

If you want to compare the sound with Harman EQ versus no EQ, you’ll need to create a new EQ profile that’s completely flat, but with a -5 dB or -6 dB preamp adjustment. This will match the SPL (volume) level to your Harman EQ profile. That way, you can toggle between them and hear the differences while keeping things roughly level-matched.

Once you get the hang of it, it’s a piece of cake. By the way, how did you like the change with the EQ?

For bands 1, 2 and 9, you can use highlighted filters to set the slope.

View attachment 467893
wahh, thank you bro, thats so clearr.. by the way can you share your 800s best settings, please?

After using the EQ, I found the sound to be calmer than before, with more focus on various aspects, such as a more solid bass, etc. The default 800s were sometimes "too flat."
But the first time I used the Harman Oratory PDF, the sound was much lower than the default, so I wondered what if I had entered the wrong PDF.

i will try to adjust 2, 3, 5, and 9 as your suggest :D
 
Back
Top Bottom