USB cable comparisons

[Superdad]

Sorry to be a cynic here, but if a 2M length of power cable makes such a huge difference after many KM of plain vanilla copper transmission lines,

and distribution transformers , then it suggests that the power supply area of the amplifier or whatever,could do with a lot of further improvement.

Even care with separation between power leads and interconnects can make a world of difference, as can ensuring that all mains plugs and sockets

are properly maintained.

Alex

 

Well the whole discussion of power cabling is off-topic in this thread, but I'll take the bait here anyway:

 

Based on decades of empirical listening and testing, I fully disagree. All my components have very well engineered power supplies, yet power cords do make a difference. So much so that not only did I build my room with walls wired with the same heavy gauge, shielded cable as my power cords (and a dedicated sub-panel, plus #0 wire to the main panel), but I paid PG&E a lot of money to have the 120-ft. of aluminum wire--from my main panel to our power-pole transformer (of which out here in the countryside we are the only users of)--replaced with copper wire. It made a very real difference.

The other side of the transformer is of course miles of very high voltage transmission, and those lines have always been--at least here in the USA for the last 45 years--aluminum.

 

BTW, for almost 3 decades I have found that the 2 legs of the 240V sound different. That is, here in the USA we have 3 wires coming to the house: 1 neutral, 1 120V, and an opposite 120V. Move a single circuit breaker one position up or down the panel and you put it on the other side of the line. To find the best sounding side, turn all the other panel breakers off, do the shift, then listen.

It is important to have amp, preamp, and DAC all on the same side of the line--whichever side sounds best. The best will not be the side the at first "wows" you and is exciting and upfront. The musically correct side is more subdued and less fatiguing. Tighten very firmly all the breaker panel screws that hold the wires. (Sometimes the 240V stoves, electric water heaters, clothes dryers, or air conditioning units will be wired to your panel with large gauge aluminum wire. Those wires need de-ox compound on them because aluminum oxide insulates, and also need to be very tight or they generate heat and vibration.) Once you know which leg of your supply you like, you can look at everything else that is on that side of the line (remember, breakers on the left and right sides of your panel are NOT opposite legs, they are interwoven so that each breaker vertically is the opposite phase from the one above or below--that is why those ganged handle double breakers work for 240V). At least try to get certain appliances, such as washing machine and refrigerator, to the opposite side of the line. My room has VARIACs (variable transformers) for control of my 120V halogen fixtures, but I advise others to put dimmable halogen lighting (and all rheostat type room light dimmers throughout the house) on the opposite side of the line from your stereo.

I wired my room to be able to switch over to 240V, and I'll probably reconfigure my power amp for that first (it is a hassle to get at the large primary jumper wires on the transformers in my amp). It may be a nice thing.

 

We now return to the USB cable discussion in progress.

Actually, I have been following this thread because I am looking for a great sounding USB cable under $300. My NOS BB1704 DAC with 24/192 async XMOS USB input does not use 5V USB power at all, so I would prefer a cable that offers 5V disconnection if possible. Right now I insert a thin strip of business card into the USB connector at the computer side to keep power off the line. That sounds better in an obvious way. So if I choose a USB cable that still has the power wire--as 98% of them do--I'll just use the same free trick.

[Superdad]

Thanks for settling that once and for all.

 

Please don't be snarky. Especially to someone's first--and reasonably thoughtful post. Sb6 might or might not be new to computer audio and/or he might have decades of listening experience and a really fine system. We need a greater diversity of voices around this place, and I'd hate to turn people off and have them thing that CA is just like AA or, heaven forbid HA.

 

Cheers,

ALEX

[Superdad]

Reverendo:

Despite my not posting to this thread (as I have nothing to contribute at this time), please be assured that I am watching with interest and appreciate your detailed observations. As amazing as my system is at this point, I am, believe it or not, still using a 0.5 meter Belkin semi-generic USB cable into my A+>NOS DAC. I am ready and willing to drop up to about $280 on a great cable. I'm sure I'll borrow a couple from The Cable Co. library first, but I'd like to narrow it down before I do.

 

So everybody, please keep these comparisons coming!

 

Thanks,

ALEX

[Superdad]

Reverendo: Do I recall correctly that you also have/had a Mapleshade Clearlink in house? If so, how does it compare to the Purist?

 

Also, is the Purist a loan checked out from The Cable Co. or a dealer--or did you actually shell out $900+ plus for it based on reputation? Not really any of my business, but I let out a small gasp when I just checked the price.

 

Really glad you are still enjoying the Cantata. I am a fan of Jeff Kalt's designs--and of the PCM1704!

 

Cheers,

ALEX

[Superdad]

...In regards to the Clearlink Plus: I sold it, since it was clearly inferior to the Diamond in my system and I was willing to cash out the extra bucks for that upgrade. It still is the best cost/benefit USB Cable that I know. Let's see if I can get an Ultimate for a special price now. Will have to send the Ultimate soon, since my friend's now heard of my listening impressions.

 

Thanks for clarifying that!

[Superdad]

The only question now is if I can bring myself to invest this kind of money in a USB cable. The results are there, but cost/benefit starts to kick in big time. Let's see if I can find a Lightspeed for a decent price.

 

Thanks for the report. Now I have another reason to be glad I backed Light Harmonic's latest campaign (Geek Pulse: A Digital Audio Awesomifier for Your Desktop | Indiegogo) over at Indiegogo for the Geek Pulse desktop DAC/headphone amp: They hit a fundraising milestone and announced that all backers will be getting one of their upcoming Lightspeed Jr. cables for free. It is supposed to be almost the same design as the expensive one, but it does not have the separately housed power line. That's okay by me since my main system DAC does not need any USB power and I already tape off pins 1 and 4 at the computer end.

 

So Reverendo, perhaps you might consider waiting and buying a Lightspeed Jr. for $99 (don't know their ship date) and seeing how close it comes the pricey one.

 

Goodnight,

Alex C.

[Superdad]

In my tests I compared the Clearlink Plus with the power leg cut and removed against the AudioQuest Diamond and the Lightspeed. The Clearlink Plus was the clear winner. I believe that removing the power leg really improved the quality of sound.

 

Dave, I guess that begs the logical question of how the Clearlink Plus compared to the AQ and Lightspeed prior to pulling the power leg.

And to carry it further, you could slip a narrow strip of business card stock (long and folder over so you can control it as you plug in) over the +5V contact of the computer end of the USB on the AQ. That way you can compare it versus the Clearlink on even footing.

 

(BTW, that is how I lift the leg on my current USB cable. Wait, that makes it sound like I am a dog peeing on it!)

[Superdad]

Who knows? That might improve the electrical continuity. You guys seem willing to try anything else ;>)

 

My dog has more iron in her diet. Not enough silver or copper. ;-O

[Superdad]

^Nice report Blake--and a great plan in the end! Hope it works out REALLY well. I'm sure you'll share the results.

 

Happy almost Turkey Day!

[Superdad]

I don't have an opinion on the sound of the Audioquest USB cables, but I do feel compelled to point out that Audioquest's marketing department is most likely close in size to the total company staff of any of the other brands you list--save for Belkin and Kimber.

And Audioquest's total marketing budget (for things like samples to reviewers) could even eclipse the total annual revenue of a few of the other firms.

 

USB cables are likely not real high on reviewers' list of components they spend time comparing. So if the Audioquest samples sound better than the generic cable they were using--bingo, it gets recommended. Not to say that comparisons have not been made. Just pointing out some obvious factors.

[Superdad]

Another problem is that when the computer is connected to I.E.C. mains earth, due to many USB devices having an internal connection between Shield and 0 volts leads, there is an earth loop.

 

I severed all connections to mains earth decades ago. All my audio gear (including computer and DAC) is floated. No main earth connection on any of my power cords. (Not that I use power strips, but lifting the wire in the power cord keeps them from seeing each others' ground pins even if they are on the same strip or outlet.) Nothing good running around on the mains earth (though I admit that for USA 120V, the neutral is bonded to "ground" way back at the panel. But my system is on a separate, dedicated sub-panel.).

And it's important to have all the audio gear on the same phase of the 120-0-120 (and to choose the better sounding side); Except for the computer. I prefer to run that on the opposite side of the line from the DAC/preamp/power amp.

[Superdad]

 

P.S.

How are things progressing on your J.S. designed Mac Mini Linear PSUs ?

 

Thanks for asking. Heading into production shortly. Lots of parts on order already. Not just for Mac minis though. Two outputs, individually selectable voltages, up to 5A+.

[Superdad]

Can you describe how you isolated the 5 volt lead?.

 

Just cut a 2mm wide x 4cm long strip of business card stock paper, insert over the contact of pin 1 of the "A" (computer end), fold back over the connector, put your thumb on it and make sure it stays straight as you insert into the jack.

 

I actually do that for both pins 1 and 4, but only because I can never remember which side is pin 1 and which is pin 4. The shell and pin 4 are common with each other anyway IIRC; very few DACs will work with just the 2 data pins and no shell connection.

 

Best,

Alex C.

[Superdad]

The data output carries no power with the V+ wire connected to usb ground

and with the bleed wire connected to the load end only

 

fmak: Your report is VERY interesting to me, though a little confusing. Are you saying that you are grounding the 5V VBUS line coming out of your computer's USB port?! That can't be right.

 

Also, not commenting specifically on your set up, but rather to everyone experimenting with DIY USB cables: AFAIK, a single twisted pair of data-only will not work, regardless of your DAC not needing 5V (to confirm connection or run). Sure, I lift both my power and "ground" pins (1 & 4) of my USB cable, but the connector shells are still joining the grounds of the two devices. I have not heard of anyone being able to completely sever that connection and still have transmission work properly (iFi USB ground "lifting" not withstanding--I think that device somehow presents ground to both host and DAC but isolates them from each other).

 

BTW, I also use Lucian's WaveIO.

 

Regards,

 

Alex C.

[Superdad]

I DIY'd my own USB cable without power (data only) and it works fine.

 

Jason:

Did you literally do just a twisted pair and not have anything soldered to the shells of the connectors?! Skipping the power is one thing (I do that too), and not connecting pins 1 and 4 is fine. But I have been told that USB simply won't work with just 2 wires and no ground connection (typically via the shells). Perhaps your computer and DAC are seeing each other's grounds via some other path (mains ground pin?).

 

Please also remind me of your computer>DAC path (anything in between? what DAC?).

[Superdad]

If there's an offer to try the cable there, I didn't see it.

 

Can you direct me to it, please?

 

Upper-left of his FaceBook page. Looks like this:

 

[Superdad]

I also am a loudspeaker designer and i have been reviewed by many magazines I don't know if you ever heard of Hales design group. Have you ever looked outside of your house and see the steel wire cables that come to your house....

 

To paraphrase from a famous political debate:

I knew Paul Hales, and you sir are no Paul Hales.

 

BTW, the high tension wires--which bring power to your neighborhood step-down transformers--are aluminum, not steel.

[Superdad]

okay so back to the original topic about describing your terminology of USB cables which you seem to be avoiding like hyper layering, plasticity can you please give me those definitions of those words explain them and how they come to be while listening to music it seems that you're avoiding the answer to the question. Hmmmmm

 

I think you don't know what you're talking about when it comes to them and you can't describe/define the words you are using. ….

….Are these words in some kind of audiobook are these words that you just made up again described to me how you would use them when you are listening to music please.

 

 

And I'm not trying to be rude...

 

It seems you don't have to try. It just comes naturally to you. Just like your run-on sentences and paragraphs.

Just saying "Cheers and happy listening" does not excuse you waltzing in here like you own the place and acting like we all just fell of the turnip truck.

 

Cheers!!

[Superdad]

Our friend appears to've been banned...

 

And no trace of all his classic run-on rants. Once he admitted to dictacting those things to his iPhone, I couldn't shake the image of him sitting there shouting at his phone. I hope he remembers to take his blood pressure medication...

[Superdad]

Today I taped over the 5v on a Wireworld Starlight 7 that I had previously disregarded and it sounds quite a bit better and I am finding that there is a characteristic sound difference in my setup with cables that do not have 5v as opposed to those that do.

 

It would be nice to have an explanation for this other than placebo or psychosis etc.

 

Well, the obvious (even if it is not the whole story) explanation is that taping over pins 1 and 4 (I assume at the computer end like I do) is keeping that voltage from even being present on the length of the cable, and from interacting with the signal pair (though the signal pair is itself separately shielded).

That's the whole idea behind the split cables in the first place--for users whose DACs do need the 5VBUS to operate.

 

And no, it's not placebo or psychosis, despite what some here want us to think.

[Superdad]

In fact, notwithstanding the redundant power lead, the basic copper Kimber sounds the best of the three.

 

But that of course begs the question of how the Kimber sounds to you with the power lead(s) taped over, since that is the topic of this moment. Just something fun to try...

[Superdad]

However, I.M.E. it's best to tape over/disconnect only +5V and use the black 0 volts return wire instead of the shield for the earth return ,which is likely to be directly connected to I.E.C. mains earth in a desktop PC.

With both Pins 1 and 4 disconnected, the shield works for the earth return ,as it is normally connected internally to the 0 volts (black) wire in the USB device itself. In other words a noisier earth return.

 

Thanks for the suggestion. What that makes me wonder is if one could then get away with disconnecting the shield at one end--and still have transmission work. While that would not accomplice true galvanic isolation, I love the idea of not having the chassises grounded together via USB shields!

[Superdad]

I tried it both ways and I did feel that taping only pin 1 yielded the best results with the blackest background.

 

Very cool. I'll have to try that.

But did you also interrupt the shield/shell at one end? That's what I want to try and have work.

[Superdad]

Not sure I understand. If the DAC does not utilize the power lead at all, why would the that particular USB connector prong be wired to anything in the DAC's circuitry?

 

Because the point of omitting the power from the cable is to not have the power running down the length of the cable next to the signal. If the DAC did use the power, then you could not do that in the first place.

 

And I asked if you did or would try that with the Kimber because you were discussing the Elijah power-less cable versus the Kimber and sort of implied that lifting the power had no benefit. But I think you just prefer the sound of the Kimber and wanted to know if it improves further if you isolate the power leg. All this at the computer end of the cable (easiest there and the only way to accomplish what we are talking about (other than to cut the wire at the computer end).

 

I hope all that makes more sense now.

 

BTW, I have compared the Swedish Supra USB--which I've had for about a year--versus some expensive cables and wow, this thing is a giant bargain ($50 retail) and seems to have it all. I encourage all to give it a try. Rich, detailed, quiet, spacious, musical, blah, blah… I have not found any faults with it so far. Then again, with something like this, one can only know in comparison to other cables--and I admit that I have not tried very many.

[Superdad]

Areal sleeper too is the Supra USB cable from Sweden. $50 and they have a USA distributor with stock. I have been using it for over a year and it has bested several cables 10 times the price. No lack of bass, no lack of detail, no fatigue (after some burn-in)--quite sweet and neutral--at least in my system.

Would love to hear from anyone else here who has tried the Supra.