[nigel801]

I use my A90 by my bedside because it is the perfect size for an end table. Using my Mojo/Poly (in fixed pre-amp mode) via 3.5mm to RCA sounds very good. While burning it in at my seated headphone station connected via XLR to a PS Audio Directream DSD and AK380cu via XLR cradle, I noticed the SQ from (input) XLR and RCA have the same sound level when the OUTPUT is 4.4mm or XLR. Your Hugo 2 is the better DAC over the D90. The D90 is a fine DAC, if a bit lean and analytical. The Hugo 2 is much more musical and authoritative. I use Roon with the Mojo/Poly and you could as well with the addition of the Chord 2Go with your Hugo 2.

Many thanks for your feedback, I knew my Hugo 2 is a better DAC than D90 but wasn't sure adding RCA to chain on A90 and using XLR output for Arya and Z1R will make any downgrade in SQ but your experience confirms its not the case. Thanks Again,

 

[Gordilocks]

Nice. That's pretty much my upcoming experiment as I'm expecting a Mojo and D90/A90 stack next week. Want to see if I'll be fine using the Mojo in place of the D90. I'm half tempted to add a Bifrost 2 and Asgard 3 into the mix. Too many choices!

I use my A90 by my bedside because it is the perfect size for an end table. Using my Mojo/Poly (in fixed pre-amp mode) via 3.5mm to RCA sounds very good. While burning it in at my seated headphone station connected via XLR to a PS Audio Directream DSD and AK380cu via XLR cradle, I noticed the SQ from (input) XLR and RCA have the same sound level when the OUTPUT is 4.4mm or XLR. Your Hugo 2 is the better DAC over the D90. The D90 is a fine DAC, if a bit lean and analytical. The Hugo 2 is much more musical and authoritative. I use Roon with the Mojo/Poly and you could as well with the addition of the Chord 2Go with your Hugo 2.

 

[sabloke]

I'm selling my Mojo as my desktop DAC is RME ADI-2 FS and on the go I use Fiio M11 Pro. Still weighing the pros and cons for paring the RME with A90. Is it worth it? My cans and IEMs are not that hard to drive but I guess A90 might do some magic paired with the German DAC. Thoughts?

 

[Arniesb]

I'm selling my Mojo as my desktop DAC is RME ADI-2 FS and on the go I use Fiio M11 Pro. Still weighing the pros and cons for paring the RME with A90. Is it worth it? My cans and IEMs are not that hard to drive but I guess A90 might do some magic paired with the German DAC. Thoughts?

Its not about wolume, but its all about refinement, parts, power supply.
Also it is good that dac and and amp have its own power supply.

 

[Sean_MR]

Would love to hear more impressions from people who have/had both a THX amp and an A90 amp! Seeing lots of people who say they can’t hear any difference, and other people who say they can actually hear a difference!

 

[RuiNguyen]

I use my A90 by my bedside because it is the perfect size for an end table. Using my Mojo/Poly (in fixed pre-amp mode) via 3.5mm to RCA sounds very good. While burning it in at my seated headphone station connected via XLR to a PS Audio Directream DSD and AK380cu via XLR cradle, I noticed the SQ from (input) XLR and RCA have the same sound level when the OUTPUT is 4.4mm or XLR. Your Hugo 2 is the better DAC over the D90. The D90 is a fine DAC, if a bit lean and analytical. The Hugo 2 is much more musical and authoritative. I use Roon with the Mojo/Poly and you could as well with the addition of the Chord 2Go with your Hugo 2.

Hello, I can see in your comment that you has Anthem STR Pre-Amp and A90. I also has Anthem STR Pre-Amp and I am thinking about buying an A90 to be used as a Pre-Amp in my second system. Is A90 good to be used as a Pre-Amp? Is it as good as Anthem STR Pre-Amp?

 

[capetownwatches]

Hello, I can see in your comment that you has Anthem STR Pre-Amp and A90. I also has Anthem STR Pre-Amp and I am thinking about buying an A90 to be used as a Pre-Amp in my second system. Is A90 good to be used as a Pre-Amp? Is it as good as Anthem STR Pre-Amp?

A90 at $500 vs Anthem at $4000..? Not really a fair fight I would say.

 

[capetownwatches]

Would love to hear more impressions from people who have/had both a THX amp and an A90 amp! Seeing lots of people who say they can’t hear any difference, and other people who say they can actually hear a difference!

My personal impression comparing THX 789 with A90 is that the Topping is the better amp to my ears, and not by a small margin either. I found extended listening with the 789 could get fatiguing due to its clinical and upfront delivery, whereas the A90 added a touch of warmth and was less etched. This with HD600/650, LCD2F and DT990 600 with hot-rodded NFB11.32 and RL Concero as sources. I could just enjoy the music for longer with the A90 which strikes a fine balance between high frequency detail and smoothness. Of course YM may well V...

 

[Flextreme]

Would love to hear more impressions from people who have/had both a THX amp and an A90 amp! Seeing lots of people who say they can’t hear any difference, and other people who say they can actually hear a difference!

Yep that is my observation too. I have a very strong suspicion that specifically with power hungry headphones, and especially planars like the Arya (that I own) and for instance LCD4 the A90 true clean power potential can show it full value. When the headphones are relatively easy to drive, and/or not a 'planar' the A90 is a perfectly good amp, but the difference to THX seems small. Some even dislike the A90 with some headphones.

For instance, my HFM edition X v2's are super easy to drive, I might even prefer the SP200 with them. But for me the A90/Arya combination is just f*&#ing magical. Coming from a SMSL SP200, the difference was massive with Arya's: warmer timbre, no harshness, more detail, sub, bass, soundstage, pace, dynamics, texture... etc....

 

[Sean_MR]

Yep that is my observation too. I have a very strong suspicion that specifically with power hungry headphones, and especially planars like the Arya (that I own) and for instance LCD4 the A90 true clean power potential can show it full value. When the headphones are relatively easy to drive, and/or not a 'planar' the A90 is a perfectly good amp, but the difference to THX seems small. Some even dislike the A90 with some headphones.

For instance, my HFM edition X v2's are super easy to drive, I might even prefer the SP200 with them. But for me the A90/Arya combination is just f*&#ing magical. Coming from a SMSL SP200, the difference was massive with Arya's: warmer timbre, no harshness, more detail, sub, bass, soundstage, pace, dynamics, texture... etc....

Thanks for the impressions! I have a pair of Stellia’s as my headphones which are super easy to drive and ridiculously sensitive. So I wonder if I wouldn’t get much benefit going from the 789 to the A90 then?

Also @capetownwatches, would you say the A90 has all of the detail and technical performance of the 789, plus the added warmth? Or is the some of the detail sacrificed for warmness? Just wondering if it really is the best of both worlds, or if it makes some small trades.

 

[MRHiFiReviews]

Would love to hear more impressions from people who have/had both a THX amp and an A90 amp! Seeing lots of people who say they can’t hear any difference, and other people who say they can actually hear a difference!

I went into my subjective opinion in this video if you want to check it out
Topping A90 Headphone Amplifier Review, The Best Reference Headphone Amp Under $500?

 

[elricofchaos72]

Hello, I can see in your comment that you has Anthem STR Pre-Amp and A90. I also has Anthem STR Pre-Amp and I am thinking about buying an A90 to be used as a Pre-Amp in my second system. Is A90 good to be used as a Pre-Amp? Is it as good as Anthem STR Pre-Amp?

Sorry for the late response. Short answer is No. As a preamp the A90 is not near as good as its Headphone portion. It can add gain via the volume knob to the preamp however. But it is not a very good preamp. Probably why Topping is making a separate P90 preamp. I had the A90 preamp connected to the Dragon IHA-1...sound quality was only average compared to other sources via A90. Hope that helps.

P.S. I did have high hopes for the A90 as a preamp, that was my initial plan. Ended up buying a Schiit Freya S instead for my headphone station. My first Schiit product ever. Very impressed with it as a preamp. Just dont sit too close to it. The volume resistors are noisy and will be heard through open back HP if seated within a few feet of the unit. Otherwise excellent preamp for the cost.

 

[jpanic4]

Would love to hear more impressions from people who have/had both a THX amp and an A90 amp! Seeing lots of people who say they can’t hear any difference, and other people who say they can actually hear a difference!

I'm comparing the 789 and A90 on an SMSL M200 and Topping E30 dac. Really hard for me to put into words since I'm not really good at describing sound like some of the others on this thread. The biggest difference to me is that since the A90 is a little warmer than the 789. And the 789 maybe due to the less warm nature seems to be better at lower end detail. It also feels like the higher are slightly brighter. Since Im using it on a HD-6XX I don't have the best opinion on soundstage. I feel like some songs sound better on the A90 and others on the 789. Sorry for confusing you even more. I have to decide if Im going to keep the 789 by tomorrow since that is the last date for a full refund return. Also there is a possibility I might sell the A90 on here. I have the volume wobble others have talked about but otherwise in excellent condition.

 

[nigel801]

Hi All, I just came across this video about distortion on RCA connection , since I am planning to use it with Hugo 2 via RCA only I need to know if anyone else facing same issue of distortion on RCA.

 

[hmscott]

With a little research I was able to mitigate the noise problem by finding RCA / XLR cables made with wire designed for really good noise rejection and EMI / RFI protection in a build that uses a Faraday cage design for the wiring. I was about to send back the A90 / D90 MQA, but the new cables got rid of so much of the noise - and the A90 / D90 MQA sound so much better now that the noise floor has been dropped so far - that I decided to keep them.

I have both RCA and XLR cables between the A90 and D90 MQA and am switching back and forth between the interconnects with that switch on the A90, I have spent hours listening on the RCA connection and it sounds great

Here are the details I posted on ASR:

Has anyone with the D90 / A90 / ? fixed or substantially improved the RCA connection "noise" by shortening RCA cables or buying better shielded RCA cables? How about better shielded USB cables?, or some other method of reducing the PC noise brought in through the USB cable? If you've debugged your noise problem to root cause + solution, please let us know the details.

Before I spend $ on new RCA / USB cables or other solutions, I'd like to know if it's worth the effort. I'd like to use RCA output from the A90 to drive power speakers, but I could put the extra $ instead into better powered speakers + XLR cables.

Thanks for the suggestions, I found these premade RCA Mogami 2534 1.5 foot / 0.5 foot sets ( 4 wire) and premade RCA Mogami 2549 (2 wire) 1.0 foot as a jumper between the A90 / D90 MQA - see their Construction and Specifications images for more details:

0.5 Foot – Directional Quad High-Definition Audio Interconnect Cable Pair Custom Made by WORLDS BEST CABLES – Using Mogami 2534 Wire and Amphenol ACPR Die-Cast, Gold Plated RCA Connectors
by WORLDS BEST CABLES
https://www.amazon.com/0-5-Foot-Directional-High-Definition-Interconnect/dp/B01ALHT7CI

1.5 Foot – Directional Quad High-Definition Audio Interconnect Cable Pair Custom Made by WORLDS BEST CABLES – Using Mogami 2534 Wire and Amphenol ACPR Die-Cast, Gold Plated RCA Connectors
https://www.amazon.com/1-5-Foot-Directional-High-Definition-Interconnect/dp/B01ALHUSYE

Mogami 2534 vs 2549 - EMI shielding vs "Sound"...?

1 Foot – Directional High-Definition Audio Interconnect Cable Pair Custom Made by WORLDS BEST CABLES – Using Mogami 2549 Wire and Amphenol ACPR Die-Cast, Gold Plated RCA Connectors
https://www.amazon.com/gp/product/B01ALFR02Y

Robert R 5.0 out of 5 stars Brand Lives Up To Its Name
Reviewed in the United States on June 23, 2020
Verified Purchase
"Very nice high quality interconnect. I did some research and the Mogami 2549 in this offering seems to be a better option vs. heavier shielded cable also offered by WBC which only improves EMI resistance. Some posts claim that the wire in this cable sounds better vs heavier shielded counterparts. At the end of the day, this is a high-quality well soldered interconnect with excellent packaging and presentation. It's serving my needs well in between my E30 DAC and 789 Amp."

The 0.5m XLR cables from SKW are working fine - no noise even at H Gain 100% volume... so for now I'll stick with those. Amazon has SKW 1.5m as the shortest length; the 0.5m length I sourced from Hifigo in China:
https://hifigo.com/products/skw-hif...ixer-amplifiers-1-pair?variant=32043150934065
https://www.aliexpress.com/item/33034630648.html
https://www.amazon.com/SKW-Balanced-Female-Microphone-2-Pack/dp/B07Q8Q16F9

Good news, the Mogami 2534 based World's Best Cables (WBC) got rid of the RCA noise. The WBC Mogami 2534 RCA cable pair also got rid of most of the USB noise.

I also got a Tripp-lite shielded cable with Ferrite Chokes, and it does reduce the small amount of GPU load noise by a noticeable amount, but just swapping in the RCA Mogami 2534 wired cable was the biggest change. A WBC Mogami 2534 XLR pair round out the cable changes.

Now I can only hear a smidge of GPU noise at 100% GPU usage, but it's so low I can't hear it while playing media - I can enable / disable the GPU load and not hear any difference in the audio. No more USB crackling either.

I can turn up the A90 volume to 100% on H Gain switched to XLR and no noise. On H Gain switched to RCA the "low level hum" without hash noise starts in at 2 oclock. So far I have no headphones that need that much drive. The highest I drive my headphones is 12 oclock on H Gain.

For now that's all good enough, and it was worth the cost and effort.

I also bought a Mogami 2549 based RCA cable pair, I'll try that out later. I'll probably pick up a WBC 2549 based XLR pair too and pair them all up together. Comments say they sound better than the 2534 heavy shielded cable, but I went with the heavy shield product first to make sure I gave the new cabling the best chance.

The cables aren't "cheap", but they aren't expensive either. If you have RCA noise problems or USB noise problems I'd recommend them as a last ditch solution before giving up on the A90 / D90.

Spoiler: New cables:

1 Foot – Quad Balanced Microphone Cable Custom Made by WORLDS BEST CABLES – Using Mogami 2534 Wire and Neutrik NC3MXX-B Male & NC3FXX-B Female XLR Plugs. *sold as a single cable, buy 2x*
https://www.amazon.com/gp/product/B00WU1BP10

1 Foot – Directional Quad High-Definition Audio Interconnect Cable Pair Custom Made by WORLDS BEST CABLES – Using Mogami 2534 Wire and Amphenol ACPR Die-Cast, Gold Plated RCA Connectors
https://www.amazon.com/gp/product/B01ALHTVMO

1 Foot – Directional High-Definition Audio Interconnect Cable Pair Custom Made by WORLDS BEST CABLES – Using Mogami 2549 Wire and Amphenol ACPR Die-Cast, Gold Plated RCA Connectors
https://www.amazon.com/gp/product/B01ALFR02Y/

Mogami 2534 wire:



Mogami 2549 wire:



WBC RCA Faraday cage wiring design:


Tripp Lite USB 2.0 Hi-Speed A/B Cable with Ferrite Chokes (M/M) 3-ft. (U023-003)
https://www.amazon.com/gp/product/B008VOPCGY

https://www.audiosciencereview.com/...d90-balanced-usb-dac-review.10519/post-475832

I can answer questions here