• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

USB high-speed isolators comparison tests

Alou

Active Member
Joined
Oct 21, 2019
Messages
146
Likes
52
Looking back on the beginning on the tread ,it just started with if USB isolation is good or not and someone pointed that you cant really tell unless you have a problem to check (a poluted USB so to speak) and its completely true,you can add anything if there is no problem you want see results.
Then a fellow forum guy pointed he just wants to try a separate 5V supply ,well ok its not a big deal to try such a thing ,experimentation always gives as lessons but to believe a solid gold ,silver ,titanium or whatever cable will make the sane speaker sound better.......ok thats were we enter the twilight zone.
 

SIY

Master Contributor
Technical Expert
Joined
Apr 6, 2018
Messages
8,993
Likes
20,654
Location
Alfred, NY
What I said is that do not care for what you call "proper listening tests". What I say, which you stubbornly refuse to accept, is that audio engineers develop capacities and perceptions that do not nee any listening test to prove they exist.

What extra insight do you get from peeking? Why do you distrust your ears?

The second sentence is hilariously wrong. At least if audio engineers are humans with human brains. Which all the ones I've met and talked with over the years sure seem to be.
 

SIY

Master Contributor
Technical Expert
Joined
Apr 6, 2018
Messages
8,993
Likes
20,654
Location
Alfred, NY
A fallacy, even if it is the case, the other kind of test is far worse and even more unreliable

Paraphrased: Not all experiments with controls are valid. But all experiments without controls are invalid.
 

Willem

Major Contributor
Joined
Jan 8, 2019
Messages
3,109
Likes
4,633
I see no real arguments from Carlmart, but only statements. Also, I see no references to any refereed pubIications. If any of my students do this I fail them.
 

Xulonn

Major Contributor
Forum Donor
Joined
Jun 27, 2018
Messages
1,802
Likes
5,958
Location
Boquete, Chiriqui, Panama
Hola from Panama, Alou,

The nice thing about audio science is that it can tell you if a certain piece of electronics can convert, amplify or modify an audio signal faithfully, and if it is electrically safe and well constructed. Testing can also tell us if a cable or accessory gizmo will preserve or modify that signal. Anyone who does not understand that concept of how science works is incapable of having an intelligent conversation about audio.

I have no idea how anyone with a modicum of intelligence can claim that the philosophy of this website is to rely on measurements alone for selecting audio components, cables and accessories. To make that claim is either a lie - or a lack of basic awareness of reality.

Based on testing and subjective comments here - and some unidentified personal subjective impulses - I chose earlier this year to buy a Topping DX7s DAC/Headphone Amp - even though I currently do not own headphones. I got a deal on MassDrop - $369 vs $499 list price - and bought one in April. When it arrived I dropped it into my system (listed below my signature) and it worked perfectly the first time I turned it on without a single problem - and has continued working that way since I bought it. It does everything I want, and I don't need a preamp anymore since it has multiple, selectable, digital inputs. The DX7s has an excellent volume control, and a nice, inexpensive remote is available if I want it. It is bigger and heavier than the micro-DACS, and I like that. In my 60+ years of playing with audio, it is one of the few components I have purchased with absolutely zero regrets after putting it into my system.

I know that there are many DACs on Amir's list that measure as well or better than the DX7s, and cost either more or less, although only a few have a remote and volume control with a positive and substantial tactile character. However, my final choice was entirely subjective. Even though I had two cheap little Topping PA3 micro-amplifiers die on me in the past year, I still went with Topping for my mid-price DAC, because it is both a heavier-duty component than the micro DACs and amps, and I saw it as a lower cost alternative to RME or Benchmark, two of thr more expensive ASR-tested DAC/HA products that I find attractive.

Regarding the topic of this thread, I see no reason to buy a "USB high-speed isolator" because testing told me that my DAC with a decent stock USB cable from my dual-booting, Linux based INTEL NUC feeding, it drives my vintage Classé Model Seventy A/B amplifier just fine. The only thing I hear in my media/office room that I don't like is uneven frequency response. Rather than fiddling with upstream components, connections, gizmos, and cables, I will work with room treatments, REW and DSP.

Unlike the false claims of the antagonist in this thread, I, like most other regulars here, use objective data for "screening" out poorly designed, manufactured, or otherwise "defective" components, and then I use subjective parameters to make a final decision. I am intelligent, aware, and experienced enough to know that there is no way any other similar good-measuring DAC at any price would sound different if all input and output parameters are within spec and ratings.
 

Alou

Active Member
Joined
Oct 21, 2019
Messages
146
Likes
52
Holla Xulon,
i came to this forum when searching for the D10 andn now i ordered the DX7pro after liking the sound of the Sabre dac so much i said to get he flagship chip and because i wanted a second dac for my office ,so the D10 will go there!
I agree with you in all.
 

mamba76

Member
Joined
Aug 12, 2021
Messages
44
Likes
5
What would be the point of testing isolators and not test the ability to isolate ?
Sure there will be galvanic separation but one also would like to measure/test how much LF and HF injected voltages/currents are attenuated.

The regen is not an isolator, the intona is.
I expect both to be 'transparant' for USB as would the HiFime be as well.

What the intona and hifime do and the regen does not is isolate.
When one wants to test the isolation a groundloop has to exist otherwise it is merely a test to see if USB signals pass (which they probably will)

Isolators will only 'help' DACs when they actually break a groundloop and one gets rid of weird noises in the audio this way.
Therefore it is pointless to test without such a groundloop IMO and one needs a DAC that is affected by groundloops in the first place to show it does what it is designed for.
When you just want to reclock and get a cleaner +5V there are other solutions (which don't do much in most cases).
What device did you use to break the ground loop ? Thanks
 

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
13,035
Likes
29,366
Location
The Neitherlands
I do not have any ground loops so do not have to break one either.
All the outlets (except for the kitchen and laundry room) in my house (and previous houses) all do not have safety ground so no (high current) loops can exist.
The point I am trying to make is that the circumstances determine where the ground loop occurs and that it needs to be broken somewhere if one hears unwanted 'sounds' caused by a ground loop.
 

Alou

Active Member
Joined
Oct 21, 2019
Messages
146
Likes
52
How can you be sure that you do have a ground loop ,you should hear something obvious like humming ?
Am asking cause i read in some post ,not here necessarily, that ground loop can exist but you want hear it because audio is masking it ,Sounds little unidentified.
How do you now you have "dirty 5v" form USB.
Amir also measured usb dacs with USB power and with external power and found no difference in sound.
All these thing with usb isolators is in debate many years now ,personaly i dont have an opinion ,i have check and done tests with older dacs and found that the usb isolator was cutting my bandwidth since it was rate for small data rates and had problem with high res 192 files ,they were not playing.With normal 44.1 files i found no difference to my ears,i cant measure ,dont have the equipment.
On the newer isolators that came out i havent tried . On the other hand since i work in the brodcast and IT industry ,most ceritified ATA80 power supplies specialy on the better worksations are generaly clean with allot of AC filters in them.We have measured allot of them not for audio purposes but still we measure for "dirty" power. Usually debates if this things work or not go on for pages and pages .But i am curious about discoveries.
 

mamba76

Member
Joined
Aug 12, 2021
Messages
44
Likes
5
In my case I am using measurement equipment to perform tests through my audio DACs (MiniDSP / REW) and when I plug the AC charger in for the laptop I get a horrible 50hz noise in my measurements. Iv ordered a couple of low cost 'full speed' USB isolators that are Galvanically isolated, so they claim. I don't need high speed as Im not streaming just for device control plus the high speed one are expensive!
 

Alou

Active Member
Joined
Oct 21, 2019
Messages
146
Likes
52
So if you don't hear a think no ground loop i guess.
Ohh by the way i have an USB isolator i no longer need,if i find it i would let one of you guys have it for free ,just pay postage.
I will look tonight!
 
Top Bottom