• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. 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 D90 Balanced USB DAC Review

spiritofjerry

Active Member
Joined
May 8, 2018
Messages
146
Likes
107
What? I don't have a ground loop issue anymore, so why would I need to do anything?

Also, you could have just placed some tape over the 5v and ground pins in your USB cable and saved $50, it's the exact same thing.

Listen, I know you think you solved your issue because you can't hear it, but you just paid money for a hacky non-fix. Like, you could have just used a cheater plug on your amp for a buck.
 

hmscott

Addicted to Fun and Learning
Joined
May 17, 2020
Messages
604
Likes
493
What? I don't have a ground loop issue anymore, so why would I need to do anything?

Also, you could have just placed some tape over the 5v and ground pins in your USB cable and saved $50, it's the exact same thing.

Listen, I know you think you solved your issue because you can't hear it, but you just paid money for a hacky non-fix. Like, you could have just used a cheater plug on your amp for a buck.
Happy to hear you have your solutions, good luck. :)
 

hmscott

Addicted to Fun and Learning
Joined
May 17, 2020
Messages
604
Likes
493
I woke up this morning to a pleasent surprise, a Topping HS01 had already been "ordered" on my account at Hifigo.com, and the HS01 is already shipped and on it's way to me. I guess they hoped I'd say "yes" to the request for testing, and they were correct. :)

It looks like my long drawn out squawk about my Topping A90/D90 "noise" issues posted here on ASR are coming around again for me to test new solutions.

A few months ago I put out an RFQ to World's Best Cables on Amazon to custom build 4 cables of lengths 3' and 6', with 3.5mm to RCA ends for field use, and so I could connect my devices with 3.5mm audio ports to my A90/TA-20 desktop setup.

I'd been through a number of progressively more expensive series of pre-built cables for 3.5mm to RCA and they all failed to block RFI/EMI in my set up. Very disappointing actually, how poorly shielded cables are made today.

The Worlds Best XLR/RCA cables built from Mogami 2534 with 4-wire quad-star faraday-cage-like shielding were the only ones I found out of a similar long hunt for RFI/EMI blocking cables that worked in my environment. So I asked WBC if they would build cables to spec using similar shielding design but modified to a light build for hand-held use.

If Ithe 3.5mm-RCA custom built cables were built using Mogami 2534 the cables would be unweildy in the field and in the hand (some are hand-held devices) with such a heavy thick cable, but Mogami makes a similarly shielded quad wire Mogami 2893 which should fill the need nicely. I'm looking forward to testing the cable for RFI/EMI rejection.

I'll post my findings as I discover them. A word about my current state of health, it's not great, so I'm much slower to "get around to it" than usual, but I do persist - so eventually I'll post something, my apologies in advance for any delay's.

I've been working up to the custom 3.5mm to RCA cable testing for quite a long time, and it is nice that Topping released the HS01 USB Isolator I can test at the same time, coincidentally I have a number of deliveries scheduled to arrive this Thursday, 11/11 that were supposed to arrive later in November and December, so it looks like some of the shipping blockages may be working themselves out for the Holidays, hopefully the HS01 won't take too long to get here.

My Kindle Paperwhite Signature Edition also arrives Thursday - and I am hoping, although I haven't seen it discussed or confirmed anywhere, that a USB-C to 3.5mm audio adapter will pass audio out the Kindle's USB-C port; then I can use one of the custom built WBC 3.5mm to RCA cables to play my Audiobooks EMI/RFI free through my A90/TA-20.

Now, perhaps someone will give the Topping U90 a try and report on it here on ASR as well. :)

If there are any updates I'll add to this post later...

Update: Sorry for the delay, I posted my first reaction to the HS01 here on head-fi, and I haven't used the Topping HS01 much since, I don't want to leave it connected because the HS01 runs far too hot compared to the ifi iDefender+ - which has no noticeable temperature above ambient - I noted the temps measured with an Infrared Thermometer set to "Objects" compared to other powered on items in that post as well. I have other things going on right now so I cannot put time into reviews - but I will try to squeeze in time to apply "noise" from the GPU to the HS01 sometime this month. Not looking promising though, as I don't think I will get past the "hot" running temperature of the HS01 - what is it doing that generates so much heat?? It should be an inert device except for switching in load for the ground loop mitigation, it shouldn't be doing "processing" of the digital signal, as it appears to be doing due to the long delay (compared to the iDefender+) when plugging in. See my post on head-fi.
 
Last edited:

trl

Major Contributor
King of Mods
Joined
Feb 28, 2018
Messages
1,980
Likes
2,547
Location
Iasi, RO
My Topping D90/A90 had lots of noise related issues to resolve
What exact issues, please?

Have you tried to disconnect all cables from D90 and A90 and leave connected only the audio cable between A90 and D90 and the two power cables? Is there still noise on your headphones?

BT streaming shows any noise?
 

antcollinet

Master Contributor
Forum Donor
Joined
Sep 4, 2021
Messages
7,698
Likes
12,992
Location
UK/Cheshire
... Very disappointing actually, how poorly shielded cables are made today...
It doesn't matter how good the shielding is if the EMI isn't going though it to the signal cables, but is conducted along it (ground loop) causing ground voltage diffferences between devices.
 

hmscott

Addicted to Fun and Learning
Joined
May 17, 2020
Messages
604
Likes
493
What exact issues, please?

Have you tried to disconnect all cables from D90 and A90 and leave connected only the audio cable between A90 and D90 and the two power cables? Is there still noise on your headphones?

BT streaming shows any noise?
My local EMI/RFI noise is from nearby power lines, cell towers, building power and facilities, and EMI/RFI from my own electronics. It is a noisy challenging environment.

Others also report EMI/RFI noise on their A90 RCA connections - requiring XLR cabling to halt it - while others reported no noise on RCA connections - the noise levels reported vary due to local environmental conditions.

And, others reported the PC USB noise independant from other environmental EMI/RFI noise as well - passed through to the A90 from the D90. My PC passes noise from my GPU and other operations through the USB 5V lines to the D90, and on through to the A90.

A while back I solved the noise problems with the A90/D90 using shielded RCA/XLR cables + ifi iDefender+ inline on my PC USB cable, and now I'm going to try using the new Topping HS01 USB Isolator - and also try new shielded cables with devices I have that use 3.5mm line outputs - I had even worse EMI/RFI interference with pre-made 3.5mm to RCA cables over the past few months.

BTW, the noise from the USB cable connected to the D90 passed through to the A90 also showed up when using another audio input on the A90, or using BT paired with the D90, until I removed the USB cable from the D90. Even if I wasn't actually using the USB input from the D90 the noise was passed through.

I ended up using 2 iDefenders, one on the D90 USB cable and one on the FiiO M15 USB cable, until I used the FiiO DK1 dock which has independent power and data USB-C connections, that was enough to interrupt the noise from the PC USB cable to the M15 directly.

Now I can use RCA only, BT, M15, etc as long as the PC USB cable to the D90 has the iDefender+ connected.
It doesn't matter how good the shielding is if the EMI isn't going though it to the signal cables, but is conducted along it (ground loop) causing ground voltage diffferences between devices.
Yup, but I had multiple sources of noise injected into the set up. I solved each one independently only to find I needed to make another mitigation to remove all the noise. Even after the RCA/XLR/USB vectors were long solved, adding 3.5mm to RCA cables brought back the EMI/RFI noise through those new cables.

Even though I had no audible "Ground Loop" noise problems through new power filters/adapters, I've moved to battery power with no ground connections at all, I use the Ravpower RP-PB187 to power the D90/A90/TA-20.
 
Last edited:

trl

Major Contributor
King of Mods
Joined
Feb 28, 2018
Messages
1,980
Likes
2,547
Location
Iasi, RO
until I removed the USB cable from the D90. Even if I wasn't actually using the USB input from the D90 the noise was passed through.
So noise comes from the ground of your laptop/computer? Then get a device that removed the ground of your USB cable and injects an external +5V. Maybe iDefender 3 + iPower or a similar combo.
 

hmscott

Addicted to Fun and Learning
Joined
May 17, 2020
Messages
604
Likes
493
So noise comes from the ground of your laptop/computer? Then get a device that removed the ground of your USB cable and injects an external +5V. Maybe iDefender 3 + iPower or a similar combo.
...A while back I solved the noise problems with the A90/D90 using shielded RCA/XLR cables + iFi iDefender+ inline on my PC USB cable, and now I'm going to try using the new Topping HS01 USB Isolator - and also try new shielded cables with devices I have that use 3.5mm line outputs - I had even worse EMI/RFI interference with pre-made 3.5mm to RCA cables over the past few months.
Yup, the iFi iDefender+ I am using is the newest revision after the iDefender3 from iFi, and it works:
https://ifi-audio.com/products/idefender-plus/
Here is the previous version iFi iDefender3:
https://ifi-audio.com/products/idefender3-0/

I am hoping the Topping HS01 works as well.
 
Last edited:
  • Like
Reactions: trl

spiritofjerry

Active Member
Joined
May 8, 2018
Messages
146
Likes
107
Yup, the iFi iDefender+ I am using is the newest revision after the iDefender3 from iFi, and it works:

I am hoping the Topping HS01 works as well.
So, you already fixed your issue, but you're buying another, more expensive product, to fix it again?
 

spiritofjerry

Active Member
Joined
May 8, 2018
Messages
146
Likes
107
So noise comes from the ground of your laptop/computer? Then get a device that removed the ground of your USB cable and injects an external +5V. Maybe iDefender 3 + iPower or a similar combo.
Better to use a true fix like a galvanic isolator. The iDefender is just a ground lift, and it doesn't always work to remove all noise as it doesn't always separate ground. As mentioned previously in this thread, you will have more luck just taping over the 5v and ground pins on your USB cable, much cheaper to boot.

If the new topping product is a true isolator as it states, then it's far superior to the ifi device.
 

spiritofjerry

Active Member
Joined
May 8, 2018
Messages
146
Likes
107
Anyway I make my own World’s Best Cables.
Have soldering iron, conquer the world!

Conclusions
All of these cables are transparent for audio. While they did pick up some noise, that happened by completely touching a power transformer. And even then, the level did not rise to audible levels (although my AP analyzer may be more immune to this noise than your audio gear). So assuming you avoid touching a transformer to your cables, electrically all three cables have bandwidth that exceeds 200 kHz, and any noise or distortion is the result of the source, not the cable.
 

Dclone

Member
Joined
Apr 30, 2020
Messages
53
Likes
46
Instead, I recommend spending the small amount of $ and get a device that is designed to accomplish the interruption of the USB power-line noise safely.

Neither ifi nor Topping are "playing Russian Roulette" with their solutions, they both disconnect the power and power-ground, there is no "danger" in that solution. Adding 5V USB external power is also safe with their products.

"Pulling the Ground pin" isn't safe, because a path to ground could be introduced to your device through an external connection. If you pay attention and are careful, then that can work safely, but I wouldn't suggest it to anyone unfamiliar with electronics and know what to watch out for down the road.

I use a Ravpower RP-PB187 ground isolated battery solution to power my Topping D90 MQA + A90/Xduoo TA-20 - and it doesn't have any other external connections that could provide a path to ground. The chassis are insulated from external grounds, and no other devices that would be grounded will be connected to them.

Again the ifi iDefender+ is only interrupting the power-line pair, in a safe noise isolating solution. Hopefully Topping's HS01 copied that functionality.

I hope when ASR members get the Topping HS01 or U90 they report to this thread and elsewhere how they work for them :)

Update: Here is a technical explainer PDF with more detailed information on what the iDefender+ does, I hope it clears up some confusion as to what the iDefender+ isn't doing as well:
Hi! I bought both U90 and iDefender+ yesterday from Shenzhen Audio. I live in Sweden so it Will take approx 1 week for them to arrive. I will use them one at a time with my D90 MQA and brand new Asus laptop. I will chose the one which sounds best for that setup and then use the other with my DX7/S or SMSL SU-9 in my other setups. Will share my findings after I have tested. Btw Shenzhen does not charge shipping costs. Have bought all my Topping and SMSL products from them.
 

hmscott

Addicted to Fun and Learning
Joined
May 17, 2020
Messages
604
Likes
493
Hi! I bought both U90 and iDefender+ yesterday from Shenzhen Audio. I live in Sweden so it Will take approx 1 week for them to arrive. I will use them one at a time with my D90 MQA and brand new Asus laptop. I will chose the one which sounds best for that setup and then use the other with my DX7/S or SMSL SU-9 in my other setups. Will share my findings after I have tested. Btw Shenzhen does not charge shipping costs. Have bought all my Topping and SMSL products from them.
Congratulations!, that's awesome.

I hope @JohnYang1997 can drop by for some insights about the HS01 and U90, and perhaps @amirm will check them out for review.

I look forward to your comments, thanks for posting :)
 

hmscott

Addicted to Fun and Learning
Joined
May 17, 2020
Messages
604
Likes
493
Anyway I make my own World’s Best Cables.
Have soldering iron, conquer the world!
Yup, that is what WBC and other budget cable builds that build for quality do, they pick the best components and use best practices in the construction and design and offer a better price than the original.

Making our own can save even more money, but cost a lot more if you aren't already set up to do it, and already have gained experience soldering and cable making. I don't recommend it to an amateur novice looking to save a few bucks unless they are prepared to invest in the tools, redo the work several times, and perhaps ruin cable/connector stock in the process. All costly entries to start up DIY cable making from scratch.

I started building cables professionally - for pay - when I was in Jr. High. I had the great fortune of making friends with a buddy whose father was an Engineer with his own consulting company, with contracts with top industry customers back in the late 60's/70's, and he took me on to apprentice.

I worked building cables, wire-wrapping, silk-screen boards, doing point to point soldering, and fine soldering on small circuits where my small hands - I was 13 to start - could fit into places grown-up hands couldn't easily reach. He specialized in test rigs for projects, test equipment builds, cable arrays for taking measurements - some hundreds of feet long. Some as small as need to fit inside fish for tracking them in rivers.

I also did a lot of other things required to take a project contract from plans to tested and calibrated end result to a customer, a great training ground to get all the skills a product engineer needs to be successful. And, I earned good money, far better than I earned selling greeting cards door to door starting at 8, and that was good money too.

After a year of apprenticeship, I had started High School, and he placed me with a larger company doing contract work for a wide range of digital and analog controls for turbine engines, working on racks of relays being converted to digital controls. They also did medical component builds, and test equipment for various medical laboratories, which meant on occasion I worked on those builds to help get them out the door.

I was on the manufacturing push line for a year there, then one day I was asked to build from plans a test rig for a new board, and after completing that, writing the test scripts for it, running a few trays of test boards through it, I graduated to test technician. After doing that for a year I was loaned out to the Engineering department to work on new designs, the first being an RCA Cosmac 1802 design.

Then I was asked to program an 8080 system in Macro Assembler an entire inventory system to track components from purchasing through incoming test through kitting for projects, and on to finished deliverables - at the same time I asked to work in purchasing to gain experience with the component costs and lead times.

So, I have had a long career of building, testing, and engineering electronics, if I wanted to build cables for fun I would, if I wanted to build cables to save money - I would chuckle to myself - and then look for well constructed cables using top components that I would use to build my own cables - to save time.

If you are trying to learn by doing DIY projects, building cables is a good start, and I recommend it. But, not for everyone, most people just want a well made cable using top components for their home systems. There is nothing wrong with that need either, because not everything needs to be built from scratch. Sometimes we just need a built assembly to use to construct an overall system to enjoy - our focus for design is higher up on the component build chain.

But, I really enjoyed building cables while I was going through the process of learning how to build them, especially the ones with dozens of wires - the big round green ones - and the long long long ones with wires and sensors potted into rods strung together for what seemed like an endless chain, to be dropped into the ocean to measure temperature layers in the depths. Fun stuff. :)
 
Last edited:

Doodski

Grand Contributor
Forum Donor
Joined
Dec 9, 2019
Messages
21,581
Likes
21,874
Location
Canada
Yup, that is what WBC and other budget cable builds that build for quality do, they pick the best components and use best practices in the construction and design and offer a better price than the original.

Making our own can save even more money, but cost a lot more if you aren't already set up to do it, and already have gained experience soldering and cable making. I don't recommend it to an amateur novice looking to save a few bucks unless they are prepared to invest in the tools, redo the work several times, and perhaps ruin cable/connector stock in the process. All costly entries to start up DIY cable making from scratch.

I started building cables professionally - for pay - when I was in Jr. High. I had the great fortune of making friends with a buddy whose father was an Engineer with his own consulting company, with contracts with top industry customers back in the late 60's/70's, and he took me on to apprentice.

I worked building cables, wire-wrapping, silk-screen boards, doing point to point soldering, and fine soldering on small circuits where my small hands - I was 13 to start - could fit into places grown-up hands couldn't easily reach. He specialized in test rigs for projects, test equipment builds, cable arrays for taking measurements - some hundreds of feet long. Some as small as need to fit inside fish for tracking them in rivers.

And, I earned good money, far better than selling greeting cards door to door starting at 8. After a year of apprenticeship, I had started High School, and he placed me with a larger company doing contract work for a wide range of digital and analog controls for turbine engines, working on racks of relays being converted to digital controls. They also did medical component builds, and test equipement for various medical laboratories.

I was on the manufacturing push line for a year there, then one day I was asked to build from plans a test rig for a new board, and after completing that, writing the test scripts for it, running a few trays of test boards through it, I graduated to test technician. After doing that for a year I was loaned out to the Engineering department to work on new product designs, the first being a Cosmac 1802 design. Then I was asked to program in assembler for an 8080 system in Macro Assembler and entire inventory system to track components through incoming test through kitting to projects.

So, I have had a long career of building, testing, and engineering electronics, if I wanted to build cables for fun I would, if I wanted to build cables to save money - I would laugh at myself - and look for well constructed cables using top components that I would use to build my own cables. :)
That's awesome!
 

mocenigo

Major Contributor
Joined
Dec 8, 2018
Messages
1,288
Likes
1,052

Conclusions
All of these cables are transparent for audio. While they did pick up some noise, that happened by completely touching a power transformer. And even then, the level did not rise to audible levels (although my AP analyzer may be more immune to this noise than your audio gear). So assuming you avoid touching a transformer to your cables, electrically all three cables have bandwidth that exceeds 200 kHz, and any noise or distortion is the result of the source, not the cable.

So stiff: Lack of sense of humour? And what is wrong by soldering your own cables? I could buy cheaper ones which most likely perform indistinguishably? Yes of course I can do that, but where's the fun? It is not that I am pursuing audiophile snake oil by taking exotic materials and unobtanium based solder...
 

spiritofjerry

Active Member
Joined
May 8, 2018
Messages
146
Likes
107
So stiff: Lack of sense of humour? And what is wrong by soldering your own cables? I could buy cheaper ones which most likely perform indistinguishably? Yes of course I can do that, but where's the fun? It is not that I am pursuing audiophile snake oil by taking exotic materials and unobtanium based solder...
A few comments up hmscott declared he had EMI noise in his cables he could hear. Unless he lives in a power transformer, or he was using fishing wire, I doubt that was the case.

I also make my own Mogami cables for their suppleness. But that's the only reason.
 

Harmonie

Major Contributor
Forum Donor
Joined
May 30, 2020
Messages
1,927
Likes
2,085
Location
France
A few comments up hmscott declared he had EMI noise in his cables he could hear. Unless he lives in a power transformer, or he was using fishing wire, I doubt that was the case.

I also make my own Mogami cables for their suppleness. But that's the only reason.

If @hmscott would be leaving in a power transformer, he would probably be safe of EMI as I would imagine it as a Faraday cage :p
 
Top Bottom