Do USB Filters Make DACs Sound Better? (Video)

[solderdude]

Would you be interested to further discuss this topic in a dedicated thread?

Not really, I know how to build and use filters to pass EMC tests with flying colors. It's a (small) part of my daily job amongst other electronic designs. In railway measuring systems though... not as tough as automotive but a lot heavier immunity and emission as well as other EMC demands as home appliances.

 

[Gatordaddy]

@amirm

Really nice work on this video. You've cut a lot of the "um"s and "uh"s and other filler which is pretty impressive since there aren't noticeable cuts in the edit. You come across as both authoritative and conversational. I'm looking forward to video commentary to supplement future speaker reviews.

For those that think video reviews are redundant: it's a lot easier to get an impression of the reviewer's opinions or priorities when the viewer is able to pick up non verbal cues. I see these being a lot easier to digest for a less technically savvy audience than the written reviews. From an objective standpoint: of course the data is the data. But for people who aren't experts (myself included) video reviews can make it easier to contextualize the measurements.

 

[Lambda]

Not really

CMC= common mode choke

The biggest German manufacturer of soft magnetic materials explicitly stats its a "CMC"= common mode choke.
@solderdude your the only source saying its not a "real" one.

 

[NoSnakeOil2]

great video! nice to see you on camera.)

 

[Oukkidoukki]

How dare they? sincerely, Greta..............no seriously, this is embarrasing audiogest, how dare you......how can you sleep at night...

 

[Lambda]

how can you sleep at night

They only ripping of the ones that want to believe. No one relay need this product, so no harm (expect financial) is done by not delivering.

In Germany we have an industry selling Placebo medicine People actually dying because they believe and refuse real treatment.

 

[Katji]

In Germany we have an industry selling Placebo medicine People actually dying because they believe and refuse real treatment.

I would bet that it was not happening in GDR.

 

[edahl]

Yes, unfortunately culturally we have gravitated from online text to YouTube videos and podcasts for most things these days.

I don't think there's anything unfortunate about it. Just find the good ones, or contribute with the good stuff if you can't find it and you're so inclined. Bullshit in tech reviews is just as present in written media.

We're fortunate to have Amir on YouTube now, and I have to say I'm highly looking forward to headphone reviews making their way there as well. Perhaps it could begin to fill the hole left by InnerFidelity?

 

[solderdude]

The biggest German manufacturer of soft magnetic materials explicitly stats its a "CMC"= common mode choke.
@solderdude your the only source saying its not a "real" one.

Look closely... this is NOT a screened coax cable in the picture. Also I have said many times a ferrite works for common mode RF.
I have never stated that it is not for common mode. It does not work for differential mode. That's why ferrites work great for radiated emission. The reason why you rarely see them is because they are expensive (compared to caps) and manufacturers only use them when they cannot meet requirements otherwise. And those are requirements for radiated emission.

A common mode choke (with separated windings) works differently, but both use ferrites and winding(s)

I have no idea what you are going on about. The info is there. There is nothing mysterious about it. Books and webpages have been written about it.
I am keeping no secrets... in fact I am doing the opposite.
I don't need to be ones teacher for EMC.

 

[Hifihedgehog]

We're fortunate to have Amir on YouTube now, and I have to say I'm highly looking forward to headphone reviews making their way there as well. Perhaps it could begin to fill the hole left by InnerFidelity?

To be fair, I would say Amir has already done this and more with the framework he has provided for us here. We already have speakers and headphones covered, across passives, actives, amplifiers, DACs and more. I just wish Tyll was around to get more people to buy into Amir and ASR because people knew him from Headphone.com or HeadRoom. I bet he would have had Amir writing articles on InnerFidelity just as he had NwAvGuy on there. I do agree text is not immune either to junk science and other audiophoolery either because people can lie or perpetuate lies under the guise of them being facts. But I still feel it does put an idea under more scrutiny when someone is forced to put down their reasoning in writing. In writing, there is less hiding behind showmanship and persona and more attention on the person explaining themselves.

 

[edahl]

To be fair, I would say Amir has already done this and more with the framework he has provided for us here. We already have speakers and headphones covered, across passives, actives, amplifiers, DACs and more. I just wish Tyll was around to get more people to buy into Amir and ASR because people knew him from Headphone.com or HeadRoom. I bet he would have had Amir writing articles on InnerFidelity just as he had NwAvGuy on there. I do agree text is not immune either to junk science and other audiophoolery either because people can lie or perpetuate lies under the guise of them being facts. But I still feel it does put an idea under more scrutiny when someone is forced to put down their reasoning in writing. In writing, there is less hiding behind showmanship and persona and more attention on the person explaining themselves.

I've been heavily involved in a YouTube channel for a couple years now, and we always write the script in advance. I think it's good practice for the reason you say, though it probably varies with subject, experience and so on.

 

[Lambda]

Look closely... this is NOT a screened coax cable

Why dose it matter here and or for this argument?
Are you saying it would be something different if it would be a coaxial wire? An ideal Bifilar Wire with conductors close together wold work the same way.

Also I have said many times a ferrite works for common mode RF.

so it is a common mode choke?

It does not work for differential mode.

Like a Ideal common mode choke... that's the point of an common mode choke high impedance in common mode, low impedance in differential mode.

The info is there. There is nothing mysterious about it. Books and webpages have been written about it.

And all of them seem to conclude a bifilliar or coaxial bifillar common mode choke with one turn is still a common mode choke.
Never saw someone stating any different.

Anyways you seem to accept that they (both) add impedance in common mode and and thereby they can reduce common mode (RF) curret!

Kirchhoff's current law tells us there need to be some sort of a loop for current to flow.
(HF-RF current can kind of "jump" trough the air a fair bit...)
On Parth this (RF) current can flow is trough the (Mains) Ground (or something else)

But in the case it dose and the Common mode current loops goes over ground i call it a Ground loop.

Is that not a ground loop for you? if not how would you call it?

No matter how you want to call them... Filters (i refer to as common mode choke) that can reduce common mode currents exist. they are widely used in industry's
USB devices that emit common mode currents also exist.
USB DACs susceptible to common mode currents also exist.

is the tested device a common mode choke? NO. can it reduce common mode currents? NO. dose it improved the audio? NO

Dose it proof all common mode choke/filter are useless snake oil. also no.

If you want to test a water filter you would not do it with clean water, would you?
If you don't have clean water (coming from you USB port) you shuld check why and if your DAC can't handle a litte bit dirt on its in put you schuld get one that can.

 

[Morpheus]

Yes, unfortunately culturally we have gravitated from online text to YouTube videos and podcasts for most things these days. That simple fact, for example, has killed off many non-specialized computer review websites who were not wise enough to expand into audiovisual content. I understand videos speak a thousand words or just say in one visual word things words never could properly convey, but I detest the current state of the medium. Most of these video "reviews" these days are just drones mindlessly regurgitating PR releases, ego-stroking and grandstanding, and only revealing the good while purposely concealing the bad. Because of that, I make it a point to only read articles when I research PC hardware, so AnandTech or bust for me. And I try to do the same with audio products when and where I can. Nonetheless, like you say, I think it is smart and even advisable to publish YouTube reviews because that is honestly the only way you can reach most people these days. Tyll Hertsens, who also on more of the objectivist side of the aisle in the world of audio, saw the value of it himself and he did the same at a point with InnerFidelity, in fact. Man, speaking of which, I wish Tyll was still around writing these days, or InnerFidelity would never have devolved into a clown show (which happened in thanks mostly to "audiophool" extraordinaire Rafe Arnott, who virtually banned half of InnerFidelity's original following from the site's comment section when they called him out for being manufacturers' lap dog) and finally the extinct dinosaur it now is.

+1 for the debacle of Innerfidelity. One of my older go to places to get sound, objectively backed advice from Tyll and also read from Bob Katz and others, a total shame after that Rafe guy took over..what a pitty, so much good work wasted..
On youtube Amir's videos..They are excellent to catch up on basics, but the written reviews are much better: more info, you can examine graphics in more detail, and much quicker to get his take but also make your appreciation of the data provided, so I hope those don't get phased out..Videos are great for general subjects in audio/ tutorials/wider breadth of analysis, as the ones that have surfaced. However, I don't have time for 35 mins of youtube, but certainly have 5 mins to scan daily what he has examined in his written reports, ASR has become sort of the weather app, always chek it out before heading out to work

 

[JimmyBuckets]

Personnaly, I don't see the benefit of video reviews.
I never look at them.

But that may be just me.

Maybe if you watched them with a usb isolator you could hear it better

 

[solderdude]

Dose it proof all common mode choke/filter are useless snake oil. also no.

If a common mode choke (with say 100 windings) and a cable with 1 to 5 windings were exactly the same and interchangeable then why do both exist ?

Yes, I have said many times that both filter common mode mode RF (but not audible range though some common mode chokes can come close).
You continue to suggest I deny that .. why ?
You also seem to suggest that for HF the source/load impedance of a ground loop is equal to the DC resistance (or resistance in the audible range)
It isn't. It's where the whole operation of common mode filtering is based on.

When there is HF in the ground loop both can lower those ground loop currents. The ferrite around a cable only a little at very high RF, the common mode choke a LOT at different frequency ranges. Both will do NOTHING for audio frequency ground loops.
They could help reduce audible noises IF they originate from RF being 'AM detected' (demodulated, rectified) by semiconductors.

 

[Lambda]

If a common mode choke (with say 100 windings) and a cable with 1 to 5 windings were exactly the same and interchangeable then why do both exist ?

If µF electrolytic capacitors exist why do ceramic capacitor with pF-fF exist?
Are vacuum capacitors no "real" capacitors because they leaking the electrolytic and have low capacity.

But both are Capacitors same way a Ferrite with 1-5 turns is low inductance common mode choke and a with say 100 windings is a higer inductance common mode choke.

You continue to suggest I deny that .. why ?

because you continue arguments like:
"real common mode filter would... ...with windings in opposite directions so the core does not saturate."
"the difference between a ferrite with a cable running through it and a common mode filter where 2 signal wires are separated and go around"
"this is NOT a screened coax cable " (sugesting one can not have a cmc on a screened coax cable?)

Your seem verry reluctant against acknowledging that small value CMC are still CMC.
And you See to deny that they can Help with current's coming/going trough GND?
Even if this currents can be in the low 100khz range?

You also seem to suggest that for HF the source/load impedance of a ground loop is equal to the DC resistance (or resistance in the audible range)

No. but if to Grounded metal boxes (PC and DAC or AVR) standing right next or in top of each other there ground loop
impedance can be "low" at high frequency's.

When there is HF in the ground loop both can lower those ground loop currents. The ferrite around a cable only a little at very high RF, the common mode choke a LOT at different frequency ranges. Both will do NOTHING for audio frequency ground loops.
They could help reduce audible noises IF they originate from RF being 'AM detected' (demodulated, rectified) by semiconductors.

I Agree with what your wanting to say.

But:
"Common mode choke a LOT at different frequency ranges." implying ferrites are no (real) CMC or that a "real" CMC has higher impedance or different physical construction.
That's like talking about real capacitors if your talking about big capacitors and not acknowledging ceramics as capacitors.
Also i like to differential between "do NOTHING for audio frequency" and "do negligible little..."

 

[solderdude]

- sigh -

 

[MZKM]

Here is tonight's video.

I would suggest that you make a Channel Trailer video, which is a video that people see on your account’s homepage; a semi-short video where you go over your job history/credentials and your goals with the channel.

 

[Adam Bernau]

@amirm Today i saw another product worthy of your attention
https://www.sotm-audio.com/sotmwp/english/portfolio-item/snh-10g/

 

[Russ_L]

Wow. Another great video to set their heads on fire on the Computer Audio BS website.

Russ