Topping A90 Headphone Amplifier Review

[hmscott]

Thanks for the reply, the noise is audible from outside the unit, both in the power cord area and in the rest, but you must bring your ear close to it and be in a quiet room, otherwise being very light it is not easy to notice. The noise does not spread through the cables from what I could see and hear, through XLRs are completely silent while if I go from RCA to M gain at high volume (3/4 of pot volume) I can hear some noise floor (it could also be the famous hum of the ground loop you guys were talking about in the previous posts). Both the D90 and the A90 are plugged in a filtered EMI/RFI power strip that is connected to wall. The D90 is fed by USB, but I tried in Optical too, the “hum” noise is exactly the same on RCA, so I think it’s actually ground loop noise and not source dependent, my source is actually surprising silent and interference free from what I can see, If I do the same test but with DAC off, I can’t hear any “hum” noise even at max volume on H gain on my headphones. I think this case of “hum” ground noise is pretty normal and easily remediable with a ungrounded high quality Power cord.

Nice description. I'll check later and post.

BTW, I'm not hearing what I consider "AC hum" when the RCA cable is connected. I only hear the USB crackle.

In H Gain with the USB cable disconnected I get a high pitched oscillation sound at Zero volume that only happens in H Gain switched on with XLR and RCA cables connected. It's definitely not "AC hum", as that has a distinct low frequency AC cycle tone.

Fortunately, with the XLR cables connected and the RCA cables disconnect in XLR only mode with the USB cable connected it is dead silent in all A90 Gain and Volume settings.

This noise floor discussion with regard to RCA connection made me curious so I tried both shorter and longer RCA cables between D90 and A90 and I can not hear any noise even in high gain at max volume level. I am using USB connection (same cable that came with D90) to D90 from my PC.
RCA cables are also cheapo cables (shorter one came with my iFi micro iDSD black label and longer one is just cheap generic RCA cable).

Both my XLR and RCA cables are 0.5m. Hifigo may get me shorter RCA / XLR cables and a split power / data USB cable to compare, I'll update about that later too.

How short in inches / cm's is your RCA (XLR?) cables?

I haven't tried the included USB cable... I'll try that later too.

 

[Seijuro]

Hello everyone. This is my first post but I've been reading this forum for quite some time. I have the D90+THX 887 stack and reading the this thread am I correct to assume that upgrading to the A90 would not audibly improve the sound quality beyond being able to use high gain with no clipping? I rarely use high gain and when I do I don't know what to listen for to detect amp clipping (I have heard clipping in a Focal Elex when the volume was too high though). From what I've seen the pre-amp to drive powered monitors seems to be the A90 only real advantage over the THX amps. One reviewer put it on par with the HPA4 which I've never heard but hear great things about despite it's insane price tag. If anyone has any experience with my present stack (THX 887 or 789) and upgraded to the A90. I'd love your feedback. Thank you!

 

[JohnYang1997]

Hello everyone. This is my first post but I've been reading this forum for quite some time. I have the D90+THX 887 stack and reading the this thread am I correct to assume that upgrading to the A90 would not audibly improve the sound quality beyond being able to use high gain with no clipping? I rarely use high gain and when I do I don't know what to listen for to detect amp clipping (I have heard clipping in a Focal Elex when the volume was too high though). From what I've seen the pre-amp to drive powered monitors seems to be the A90 only real advantage over the THX amps. One reviewer put it on par with the HPA4 which I've never heard but hear great things about despite it's insane price tag. If anyone has any experience with my present stack (THX 887 or 789) and upgraded to the A90. I'd love your feedback. Thank you!

Quieter with sensitive iems. 4.4mm output jack. Internal power supply.

 

[Veri]

Hello everyone. This is my first post but I've been reading this forum for quite some time. I have the D90+THX 887 stack and reading the this thread am I correct to assume that upgrading to the A90 would not audibly improve the sound quality beyond being able to use high gain with no clipping? I rarely use high gain and when I do I don't know what to listen for to detect amp clipping (I have heard clipping in a Focal Elex when the volume was too high though). From what I've seen the pre-amp to drive powered monitors seems to be the A90 only real advantage over the THX amps. One reviewer put it on par with the HPA4 which I've never heard but hear great things about despite it's insane price tag. If anyone has any experience with my present stack (THX 887 or 789) and upgraded to the A90. I'd love your feedback. Thank you!

If the 887 suffices there's no "real" reason. The A90 has SE/XLR pre-amp out, and like John mentions better low-level performance for IEMs etc. But the 887 is no slouch. The pre-amp and 4.4mm output is one of the main benefits imo.

 

[PCZ_97]

Hello everyone. This is my first post but I've been reading this forum for quite some time. I have the D90+THX 887 stack and reading the this thread am I correct to assume that upgrading to the A90 would not audibly improve the sound quality beyond being able to use high gain with no clipping? I rarely use high gain and when I do I don't know what to listen for to detect amp clipping (I have heard clipping in a Focal Elex when the volume was too high though). From what I've seen the pre-amp to drive powered monitors seems to be the A90 only real advantage over the THX amps. One reviewer put it on par with the HPA4 which I've never heard but hear great things about despite it's insane price tag. If anyone has any experience with my present stack (THX 887 or 789) and upgraded to the A90. I'd love your feedback. Thank you!

The 887 is great, atm I own both the 887 and the A90, they are very similar and not far from each other performance wise, I’m A/Bing both and I can actually distinguish both all the time, probably thanks to very revealing headphones like the HD800S too, the 887 is a little less refined up in the treble, they are both linear and neutral, the A90 is a little warmer and slightly forgiving (don’t expect by a lot) compared to thx amps, it puts you in a bigger room and imaging is impressive, it has better control too. Details wise, they are both top notch. The THX is more intimate but I can say that the main difference for me was the imaging and soundstage capability of the A90, in this respect it is audibly superior to THX. That said, you may like the intimate presentation of THX amps more tho. It’s an upgrade? I would say yes, but don’t expect impressive change, the only real audible improvement would be in imaging and soundstage capability, slightly better control, more refined up top and you can add the other features people mentioned above, so it’s up to you.

 

[Seijuro]

Thank you for the replies!

 

[Veri]

I’m A/Bing both and I can actually distinguish both all the time

Ok but can you prove that at all ? Anyone can make extraordinary claims.

 

[Matias]

Here is the photo of my D90 + A90 stack which now completed after I received my Topping A90 yesterday. I was using Monolith THX 887 before as main amplifier. I got it within 6 days from the order (including 2 extra days it took after arriving in my country as it was just sitting (Thanks to DHL who is taking 3-5 days extra after the shipment has arrived in my country due to current COVID-19 situation). Ordered from Shenzhenaudio through aliexpress and these guys are always pretty fast with order processing and shipping. I order my Topping D90 through them as well back in early January.

View attachment 70300

Very nice! How a photo with both turned on, a headphone cable plugged in and volume somewhat louder as if in use?

 

[PCZ_97]

Ok but can you prove that at all ? Anyone can make extraordinary claims.

I can't prove it obviously, I can just share some photos to show that I own them both, btw would you gently tell me what "extraordinary claim" I'm making? Because I think I have described both well without exceeding in any sector as some audiophiles do on other forums, mine are strictly personal opinions and are related to my setup, everyone is obviously free to think what he wants. Counts that I'm still not sure if I want to sell the 887 because I consider it somehow a little different from the A90 that I can justify owning both, in that the 887 is completely colorless sound wise and in some situations I appreciate it more than the slightly warmer A90, I still have to do other days of listening to better evaluate, but I repeat, these are MY strictly personal opinions on the two amps atm. So yes, anyone can make “claims”, I’m just making mine, free to think what you want .

 

[hmscott]

Thanks for the reply, the noise is audible from outside the unit, both in the power cord area and in the rest, but you must bring your ear close to it and be in a quiet room, otherwise being very light it is not easy to notice. The noise does not spread through the cables from what I could see and hear, through XLRs are completely silent while if I go from RCA to M gain at high volume (3/4 of pot volume) I can hear some noise floor (it could also be the famous hum of the ground loop you guys were talking about in the previous posts). Both the D90 and the A90 are plugged in a filtered EMI/RFI power strip that is connected to wall. The D90 is fed by USB, but I tried in Optical too, the “hum” noise is exactly the same on RCA, so I think it’s actually ground loop noise and not source dependent, my source is actually surprising silent and interference free from what I can see, If I do the same test but with DAC off, I can’t hear any “hum” noise even at max volume on H gain on my headphones. I think this case of “hum” ground noise is pretty normal and easily remediable with a ungrounded high quality Power cord.

The sound is standard transformer mechanical noise - but super low - and comes on after flipping the front switch to HPA, right after the relay click which is much louder.

I have to put my ear right against the case of the A90 to hear it. Even with everything turned off other than the A90 there is enough background noise to make the sound inaudible at a 1/2 inch away from the A90 case.

I don't hear anything like that through my headphones. All I get is dead silence in all Gain modes L/M/H with the volume at 100%.

That's the kind of hum frequency I would expect to hear via a ground loop, and I am not hearing that through the headphones.

What I hear when using the RCA connection between the A90 and D90 MQA is coming from the USB cable passing PC hash and that internally generated high pitched noise in H Gain 0% volume with RCA / XLR cables attached.

Given the materials and cost of the A90 I think the transformer mechanical noise is well damped and controlled.

 

[PCZ_97]

The sound is standard transformer mechanical noise - but super low - and comes on after flipping the front switch to HPA, right after the relay click which is much louder.

I have to put my ear right against the case of the A90 to hear it. Even with everything turned off other than the A90 there is enough background noise to make the sound inaudible at a 1/2 inch away from the A90 case.

I don't hear anything like that through my headphones. All I get is dead silence in all Gain modes L/M/H with the volume at 100%.

That's the kind of hum frequency I would expect to hear via a ground loop, and I am not hearing that through the headphones.

What I hear when using the RCA connection between the A90 and D90 MQA is coming from the USB cable passing PC hash and that internally generated high pitched noise in H Gain 0% volume with RCA / XLR cables attached.

Given the materials and cost of the A90 I think the transformer mechanical noise is well damped and controlled.

Thanks for checking it out, I was just curious. Through RCA I can only hear the “hum” if I’m raising the volume passing half pot in H gain, or 3/4 volume pot in M gain, so I believe it’s just ground noise, I can’t hear any USB noise in my setup, I’m going to try an hq ungrounded power cord and see if the hum disappears.

 

[fendy323]

Hello, im new on this audio world,
i've plan to build my endgame rig,
i buy sennheisher hd 800s and still confused to choose the dac/amp, and someone suggest me to buy topping A90 with D90 for combination, is it a perfect setup for my hd 800s ?
and from comment below i notice that topping plan to launch P90, should i wait ? and if p90 already launch, which combination should i buy ?
Stick to D90+A90?
P90+D90?
P90+A90?
Or buy three of them?

 

[JohnYang1997]

Hello, im new on this audio world,
i've plan to build my endgame rig,
i buy sennheisher hd 800s and still confused to choose the dac/amp, and someone suggest me to buy topping A90 with D90 for combination, is it a perfect setup for my hd 800s ?
and from comment below i notice that topping plan to launch P90, should i wait ? and if p90 already launch, which combination should i buy ?
Stick to D90+A90?
P90+D90?
P90+A90?
Or buy three of them?

There's no p90. It's either preamp pre90 which is for the power amp in the future, or P90 power supply which doesn't exist.

 

[fendy323]

There's no p90. It's either preamp pre90 which is for the power amp in the future, or P90 power supply which doesn't exist.

so when preamp pre90 launch, should i buy too? for combining with a90+d90

and how about d90 + a90 for hd800s ? is it perfect combination for endgame rig at this time?
or should i add more money for buy the another combination..?

 

[odyo]

so when preamp pre90 launch, should i buy too? for combining with a90+d90

and how about d90 + a90 for hd800s ? is it perfect combination for endgame rig at this time?
or should i add more money for buy the another combination..?

D90+A90 one of the best you can buy but to be honest you don't need to spend too much for dac amp. I see you are new. Dac, amp world is an audiophile rabbit hole and unnecessarily complex with subjective opinions. So no one can say buy this or that to you with 100% certainty. You don't need p90 or anything btw.

 

[Veri]

Hello, im new on this audio world,
i've plan to build my endgame rig,
i buy sennheisher hd 800s and still confused to choose the dac/amp, and someone suggest me to buy topping A90 with D90 for combination, is it a perfect setup for my hd 800s ?
and from comment below i notice that topping plan to launch P90, should i wait ? and if p90 already launch, which combination should i buy ?
Stick to D90+A90?
P90+D90?
P90+A90?
Or buy three of them?

You don't need future product P90 for HD800. you should read up about the basics maybe? I feel like you're gonna throw/spend money without really knowing much

 

[fendy323]

D90+A90 one of the best you can buy but to be honest you don't need to spend too much for dac amp. I see you are new. Dac, amp world is an audiophile rabbit hole and unnecessarily complex with subjective opinions. So no one can say buy this or that to you with 100% certainty. You don't need p90 or anything btw.

hmm, so what should i buy for drive hd800s perfectly bro?
really confused about it, someone even suggest me buy hugo 2 but i figure it out some member said the power not enough.

You don't need future product P90 for HD800. you should read up about the basics maybe? I feel like you're gonna throw/spend money without really knowing much

yepp, im new and confused to drive my headset , the reason i asked p90 maybe because someone said p90 preamp will launch soon, and its make me not sure buy d90+a90 right now or wait p90

basiclly maybe i only need the rig for drive hd800s perfectly, and stop buy anything (if not really improve) for the headset in the future

 

[Veri]

A90+D90 should suffice for many years to come.

 

[Seijuro]

I have a HD800s with a THX 887 + D90. I run them balanced XLR and on medium gain rarely go past 1 o'clock.

 

[Gnadna]

I can't prove it obviously, I can just share some photos to show that I own them both, btw would you gently tell me what "extraordinary claim" I'm making? Because I think I have described both well without exceeding in any sector as some audiophiles do on other forums, mine are strictly personal opinions and are related to my setup, everyone is obviously free to think what he wants. Counts that I'm still not sure if I want to sell the 887 because I consider it somehow a little different from the A90 that I can justify owning both, in that the 887 is completely colorless sound wise and in some situations I appreciate it more than the slightly warmer A90, I still have to do other days of listening to better evaluate, but I repeat, these are MY strictly personal opinions on the two amps atm. So yes, anyone can make “claims”, I’m just making mine, free to think what you want .

I have the smsl sp200 which should be quite close from the 887 as well as the A90. I can confirm most of PCZ_97 impressions. A90 is slightly warmer (bass and low medium). the thx feels a bit more energetic though. Both units are really good. I was not expecting such quality for moderately priced units coming out from a Spl phonitor which just died.