XXHighEnd

Ultimate Audio Playback => Your questions about the PC -> DAC route => Topic started by: boleary on February 15, 2010, 01:19:57 pm



Title: S/PDIF Cable
Post by: boleary on February 15, 2010, 01:19:57 pm
I'm currently connecting my usb/spdif converter (M-Audio) to my dac with a 12 inch, six dollar spdif cable. In anticipation of getting the Hiface happening, I am wondering if upgrading such a short cable will make much of a difference. Prices of cables are really unbelievable. Is a .5 meter cable that costs $125 really worth it?
 


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 01:56:57 pm
Hi Boleary,

If you are handy, you can DIY, I have a nice recipe.

Belden 1694A or 1505A coax cable with Eichmann Silver Bullet RCA Plugs.

It will cost you half the price (depends on costs Eichmann) and much better sound then any prefab.
This will sure make a difference for the better.
Don't spend high amounts of money on a cable, you will be disappointed.


Title: Re: S/PDIF Cable
Post by: boleary on February 15, 2010, 02:15:04 pm
Thanks Roy. I'm sorta handy and could probably handle this task. The Eichmans are expensive and I assume are totally worth the cost.


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 02:23:09 pm
I have already made a dozen of these for my friends.
This cable is best value for your money.

I can made a guide on how to build, material list etc.
Its not that hard, the only thing you should worry about is not firing up your eichmanns with a too hot solder iron.
If you can't get Belden cable, I can send it over to you. (availability depends on continent)
And look for a good price on the eichmanns, because they are sometimes sold for twice as much.

Roy


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 02:35:03 pm
Just checked.........I still have some mtrs of Belden 1694A.
And have an adres here in Holland for the SilverBullits.
They also deliver per/two

If there is interest I can make some more.


Title: Re: S/PDIF Cable
Post by: boleary on February 15, 2010, 02:37:03 pm
Again, thanks Roy. If you are willing, I'll take a guide since I've never done it before, otherwise I can ask Uncle Google. The cheapest I've found the Eichman's thus far is $139 for a set of 4. Know anyone who sells just a pair or is four the minimum amount?


Title: Re: S/PDIF Cable
Post by: boleary on February 15, 2010, 02:44:51 pm
Of course I'm interested. Just sent you an email.


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 03:23:57 pm
You could also use the copper bullits they are much cheaper.
But if you choose the copper version, you could also take any kind of RCA.

Just made a phone-call on the silverbullits, they cost 24euros each

complete cable costs about 90euro incl pp. (and will look better then the one on pic)

But keep in mind a standard I2S connection will do much better.
But who has I2S, at this point! ;)


Title: Re: S/PDIF Cable
Post by: PeterSt on February 15, 2010, 03:31:38 pm
;)


Title: Re: S/PDIF Cable
Post by: PeterSt on February 15, 2010, 03:46:30 pm
Btw, I don't want to discourage anyone, but keep in mind the current currency rate, which is 1.36.

IMO a good digital cable is more important than a good interlink.

And boleary, on this matter, using RCA connections on a 75Ohm cable is not the best thing to do. That should be BNC ...
(hence, you don't want to change something about the HiFace, right ? :) :))

(*and* those cables :swoon:)


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 03:56:43 pm
Quote
IMO a good digital cable is more important than a good interlink.

I think both are equally important, but I did lots of expermenting on SPdif and some are sounding truly awful.

Quote
And boleary, on this matter, using RCA connections on a 75Ohm cable is not the best thing to do. That should be BNC ...
(hence, you don't want to change something about the HiFace, right ?  )


BNC is the best connection for SPdif, but you need a special tool to make a decent BNC connection.

Hiface is also in BNC available, what about your DAC ?

Otherwise its best to use Canare BNC connectors.

Next best is the Eichmann Silver Bullit (or equal)


Title: Re: S/PDIF Cable
Post by: boleary on February 15, 2010, 04:01:37 pm
Well, BNC sounds great but my dac 's spdif input is rca. It also has a balanced AES/EBU but no way to use it.


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 04:10:27 pm
Quote
Btw, I don't want to discourage anyone, but keep in mind the current currency rate, which is 1.36.

This will be your problem too, Peter !

How much for NOS1 in Dollar ??  :dancing:


Title: Re: S/PDIF Cable
Post by: han on February 15, 2010, 04:23:17 pm
Hmm,

This discussion gives me the chance to pose my question about Firewire cables again....

Am I right that even the quality of cables in the digital part are important if we consider SQ?

Anybody experience with Firewire cables maybe?  :yes:

Regards, Han


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 04:28:42 pm
The best connection is NO connection, so everything in between will alter SQ.

I can imagine for FW that will be the same. (or I2S) (or wait for super-conductors)

I don't know if there are good connectors available for DIY, cable is not the biggest problem.

But are there decent FW or I2S connectors on the market yet ?

I dunno....


Title: Re: S/PDIF Cable
Post by: PeterSt on February 15, 2010, 05:13:20 pm
i2s connectors do not exist, since i2s does not exist as external connection.

FW cables should not be all that important, because what's transferred over them is just digital and error checked.
Btw, I once tried to make a FW cable myself, but it didn't want to work. Never understood why.


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 05:29:40 pm
Quote
i2s connectors do not exist, since i2s does not exist as external connection.

Yes, you are right!
What connectors are you planning to use on NOS1 then??
RJ-45 DIN/cat5 connector or some other 5/6 pins mini-DIN connector.

I think CAT5 can be an option for the cable, also from Belden 1585A (Teflon) or something like that.


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 15, 2010, 05:41:28 pm
There are I2S Cables Available (http://www.revelationaudiolabs.com/cables-digital/index.htm#i2s)
There are I2S Cables Available (http://www.revelationaudiolabs.com/cables-digital/index.htm#CAT5-RJ45-i2s)

But is there a standard, guess not. (ISO)


Title: Re: S/PDIF Cable
Post by: PeterSt on February 15, 2010, 11:25:58 pm
Quote
What connectors are you planning to use on NOS1 then??

None ... No external i2s for sure ...


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 16, 2010, 12:02:03 am
Quote
What connectors are you planning to use on NOS1 then??

None ... No external i2s for sure ...


With your plans do we still need a SSD in PC for better SQ ?
 :)


Title: Re: S/PDIF Cable
Post by: manisandher on February 17, 2010, 12:14:57 pm
I don't actually use RCA spdif cables in my setup (I use dual-wire AES for signal and BNC for wordclock, between the Weiss and PMII). However, I came across this thread quite a while ago that intrigued me: http://goodsoundclub.com/Forums/ShowPost.aspx?postID=5565#5565.

From the thread, apparently the old Belkin Synapse Platinum Digital cables (the blue ones from the 1990s) are the 'dog's bollocks', as we say here in the UK. You may notice that there is a poster called 'miab' who is offering these cables for $65 each plus shipping. I've just ordered a couple of these from him, and they should be in the post to me right now. I'm hoping to be able to convert one to BNC and use it for my wordclock. Assuming I don't screw it up and need the other one, I may have one spare. I'd be happy to sell it for the price I paid for it (even if I'm hit with customs duty, the price shouldn't be more than £60 plus shipping). Alternatively, you might want to contact miab directly to ask if he has more...

If you're thinking of another solution, one thing to bear in mind is that cable length is important. Some people believe that too short is no good! See http://www.positive-feedback.com/Issue14/spdif.htm.

Mani.


Title: Re: S/PDIF Cable
Post by: PeterSt on February 17, 2010, 12:33:11 pm
Quote
Some people believe that too short is no good!

IMO this would be specifically true when the termination isn't right. And ... with any 75 Ohm cable and RCA connectors this would be the case (not correctly terminated). So, you'll get reflections, and the longer the cable, the less impact the reflections have (onto the original output).

(I didn't read that link, and I hope it tells similarly :))


Title: Re: S/PDIF Cable
Post by: boleary on February 17, 2010, 12:49:21 pm
Thanks Mani. I'll definitely check out that thread, though I've settled on a solution. My next question concerns interconnects. Having read this article, http://consumerist.com/2008/03/do-coat-hangers-sound-as-good-monster-cables.html, a while ago, I've never taken them too seriously. However, after hanging around here for the last year or so I think I need to ask: anyone have suggestions on interconnects? How much do they matter?


Title: Re: S/PDIF Cable
Post by: manisandher on February 17, 2010, 12:57:23 pm
I didn't read that link, and I hope it tells similarly :)

You're bang on. So, you're not just a pretty face after all ;)

Mani.


Title: Re: S/PDIF Cable
Post by: boleary on February 17, 2010, 01:06:40 pm
Forgot to ask: So whats the optimal length for an S/PDIF cable, 75 ohm, rca connectors?


Title: Re: S/PDIF Cable
Post by: manisandher on February 17, 2010, 01:21:17 pm
...anyone have suggestions on interconnects? How much do they matter?

How big is your can for the worms that'll sprawl out of asking such a question?

FWIW, many years ago, I tried more (analogue) cables than I can remember - both interconnects and speaker cables. I spent a veritable fortune on this endeavour.

I found that I really didn't like silver-plated or solid silver... at all. No matter what the make, or price (and I'm talking thousands of dollars here). I even tried solid gold (yes, solid gold) which I liked a lot more than any silver one. I actually still have these... but have them 'wasting away' in my office system.

There were two makes/models that I preferred over all the others.. and they were a fraction of the price of the silver/gold ones I tried. One was Van den Hul 'The Second' interconnects and speaker cables. Probably too 'dark' for most people, but such a natural and full tonal texture. The other was Analysis Plus Solo Crystal interconnects and speaker cables. Indeed, I use these exclusively in my main system - with active crossovers and 8 amps, as you can imagine, I'm using a lot of these cables. I didn't care at all for the more expensive Analysis Plus silver- and gold-plated cables - I actually hated the former.

Now, I'm certainly not suggesting that you do what I did - actually buy the cable then sell what you don't like at a massive loss, if at all. (In fact, I probably have the world's most expensive cabling in my car, becaue I couldn't sell it. But my car is so noisey that I can't hear a thing anyway!)

Try to find a retailer who will let you return what you don't like... that's my only advice really.

Mani.


Title: Re: S/PDIF Cable
Post by: manisandher on February 17, 2010, 01:22:24 pm
Forgot to ask: So whats the optimal length for an S/PDIF cable, 75 ohm, rca connectors?

Over 1.5m, according to Dan Lavry...

Mani.


Title: Re: S/PDIF Cable
Post by: manisandher on February 17, 2010, 01:42:15 pm
... that's my only advice really.

Actually, that's not my only piece of advice. On top of this, I would say stick with good quality pure copper over anything else (except maybe carbon). Even then, the insulation material/geometry will have an effect, and this is why you're going to have to listen to it in your own system.

A final thought - don't forget that there will be cabling inside your electronics and speakers that may ultimately act as the weakest link. This is why I have my speaker cables soldered directly onto my speaker drivers. But I don't intend to do the same thing with all my electronics!

If I had to do it all over again, I'd stick with cheap OFCC cables from my local electronics supplier... honestly. There are far more important nuts to crack, IMHO... like taking the digital 'glare' out of digital - something that Engine#4 looks like it's going to help us do.

Mani.


Title: Re: S/PDIF Cable
Post by: boleary on February 17, 2010, 01:44:41 pm
Again, thanks Mani!


Title: Re: S/PDIF Cable
Post by: PeterSt on February 17, 2010, 01:49:56 pm
About my earlier mentioned "don't go over 1m for SPDIF" ... a long time ago I learned by heart (from whereever) that 90cm would be a good length. Today ? I don't know. I have always be ignorant and used a cable as short as possible with 75 Ohm RCA connectors (they do exist). So, now I indeed read that article from/about Steve, and when the internal circuitry doesn't comply to 75 Ohm termination, YMMV.

In the mean time I read this a while back from Steve, and I think it is really good : http://www.empiricalaudio.com/computer-audio/audio-faqs/short-versus-long-cables
This is about the tradeoff between long interlinks and short LS cables, and vise versa.


Title: Re: S/PDIF Cable
Post by: manisandher on February 17, 2010, 01:52:57 pm
Hey Peter, have you ever discussed carbon cables with a particular neighbour of yours?

Mani.


Title: Re: S/PDIF Cable
Post by: PeterSt on February 17, 2010, 01:59:50 pm
No, but if he steps inside (Van den Hul) he will probably start crying, and next will think I can't be serious about such a subject.


Title: Re: S/PDIF Cable
Post by: manisandher on February 17, 2010, 02:10:45 pm
Thinking about it, I probably liked his 'The Second' cables because I was using a pair of B&W N802 speakers at the time, which are just way too bright ordinarily. I sold these to my sister, and still have to cover my ears whenever I'm at her place, because they sound so grating... even with the 'darkness' that the VdH The Seconds bring to the party.

Nice article BTW; http://www.empiricalaudio.com/computer-audio/audio-faqs/short-versus-long-cables. Cables really are a bottomless pit though. Like I said earlier, there are much bigger nuts to crack in audio... IMHO.

Mani.


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 17, 2010, 04:48:01 pm
Thnx Mani for stepping in, (and Peter)

And for providing some decent links
I have a disc somewhere with all my links from the past on making good cables.
But can't find a damm thing anymore. (long time ago)
And things are changing at such a fast rate.

Boleary's wish in length is too short, also my advise 0.80m-1.50m certainly not shorter.

About those connectors indeed they should be 75ohm, but I can not believe the M-audio or MSB or Hiface has perfect 75ohm Receptacles, (yea, BNC on HiFace, OK)
or even a precision 75ohm resistor on their part.
It doesn't stop with just the cable, when you take a look inside your equip. you start to wonder why invest in a expensive cable at all, without doing the inside too.
And with equipment I also mean: the expensive sh|t too.

There are 75ohm RCA connectors indeed.
http://www.canare.com/ProductItemDisplay.aspx?productItemID=40
But you have to look what connector fits the Belden 1694A cable for eg.

Personally I have good experiences using Eichmann on WBT Next-gen Receptacles (analog and digital)
But then again for digital BNC is better and cheaper, but not always do-able, and if you make just 1 cable,
you have to buy a BNC krimp-tool too.(??$)

Btw. I always peal off the outside PVC cover from the cable and use teflon plumbers tape instead.
And I always make a seperate ground connection instead of using the outside shielding mesh of the cable)
Leave the mesh and foil in place, but don't connect it to ground, use seperate wire for that.

But your options are still open Boleary............
Don't make your decision that fast, do some reading about the subject. (you don't have the hiface yet, anyway)

You could also try to get some canare 75ohm RCA connectors, (US only, I believe) they are much cheaper then eichmann (maybe 15$ per 2)

And for last, its always hard to judge, when not listened to what you actually buying.
But you have no choice with DIY.
And dealers that provide a decent means of trying them out, mostly provide you with far too expensive cables.
But don't forget you always have the right to return after several days. (even if you buy on the internet)

getting crazy already...hehe

Grtz

Roy
 


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 17, 2010, 05:59:58 pm
From the thread, apparently the old Belkin Synapse Platinum Digital cables (the blue ones from the 1990s) are the 'dog's bollocks', as we say here in the UK. You may notice that there is a poster called 'miab' who is offering these cables for $65 each plus shipping. I've just ordered a couple of these from him, and they should be in the post to me right now. I'm hoping to be able to convert one to BNC and use it for my wordclock. Assuming I don't screw it up and need the other one, I may have one spare. I'd be happy to sell it for the price I paid for it (even if I'm hit with customs duty, the price shouldn't be more than £60 plus shipping). Alternatively, you might want to contact miab directly to ask if he has more...

Hey Mani,

A good SPdif cable is important because data and clock are combined in one signal.
So if data and clock are split up, cable becomes a bit "less" important

Do you have experiences in using different cables on just the wordclock ??

I thought this should only be a decent shielded 75ohm cable with BNC connectors.
Nothing more nothing less.
Or maybe this is actually what you are doing.

Roy


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 17, 2010, 06:02:53 pm
Also a good site for DIY and cables:

http://www.vhaudio.com/


Title: Re: S/PDIF Cable
Post by: PeterSt on February 17, 2010, 06:56:02 pm
Quote
So if data and clock are split up, cable becomes a bit "less" important

Maybe not Roy. Because then both have a relation in separate cables. :yes:


Title: Re: S/PDIF Cable
Post by: Ava12 on February 17, 2010, 07:03:09 pm
I'm currently 'designing' the digital inputs of my new dac and the outputs of my sources (mainly the M-Audio FW interface of course^^) and it struct me, why not use lab-like cables for the SPDIF signal like Aircell 5 or RG58/RG214. Well I'll try this.
My question is, are there different BNC plugs for 50Ohm and 75Ohm? Or is it one and the same?
Greetz Ava


Title: Re: S/PDIF Cable
Post by: PeterSt on February 17, 2010, 07:10:22 pm
The BNC plugs are different too. But why use a 50 Ohm cable where 75 is "needed" ?


Title: Re: S/PDIF Cable
Post by: Ava12 on February 17, 2010, 07:21:50 pm
You're right why hastle, I thought there're higher quality cables in 50Ohm (RG214) but ok, then these are only better at higher frequencies than the 2.8MHz, we're using.
It wouldn't have made a difference to just use 50Ohm resistors instead of the 75Ohm ones, that's why I thought "just try"^^.
I'll try some RG59 then, with 0.1% 75Ohm resistors :)
Greetz


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 17, 2010, 07:26:26 pm
The value for the impedance depends on the input resistor.
Kinda impedance correction, if resistor and chip-to-chip connection is 75ohm.
This rules out the total capacitance of cable.
Correct me if I'am wrong here.

also:
75 ohms: The characteristic impedance 75 ohms is an international standard, based on optimizing the design of long distance coaxial cables. 75 ohms video cable is the coaxial cable type widely used in video, audio and telecommunications applications. Generally all baseband video applications that use coaxial cable (both analogue and digital) are matched for 75 ohm impedance cable. Also RF video signal systems like antenna signal distribution networks in houses and cable TV systems are built from 75 ohms coaxial cable (those applications use very low loss cable types). In audio world digital audio (S/PDIF and coaxial AES/EBU) uses 75 ohms coaxial cable, as well as radio receiver connections at home and in car. In addition to this some telecom applications (for example some E1 links) use 75 ohms coaxial cable. 75 Ohms is the telecommunications standard, because in a dielectric filled line, somewhere around 77 Ohms gives the lowest loss. For 75 Ohm use common cables are RG-6, RG-11 and RG-59.


Title: Re: S/PDIF Cable
Post by: AUDIODIDAKT on February 17, 2010, 07:42:59 pm
The reason why the cable must have a for eg. 75ohm load,
is because the impedance of a cable is changed with frequency.

If there is no 75ohm load, mismatch will happen at certain freq.

but there is also:

risetime, dispersion, skin effect etc etc
also the architecture of the cable, the distance between dataline and ground.


Title: Re: S/PDIF Cable
Post by: manisandher on March 14, 2010, 01:41:01 am
Do you have experiences in using different cables on just the wordclock ??

I thought this should only be a decent shielded 75ohm cable with BNC connectors.
Nothing more nothing less.
Or maybe this is actually what you are doing.

Yes, this is exactly what I'm doing.

I haven't tried too many BNC wordclock cables. The one I use at the moment is a very reasonably priced one made by a UK company called Trichord (trichordresearch.com). As you said, it's a simple shielded 75ohm cable with BNC connectors - nothing more, nothing less.

Mani.