70ft best cable: long AES or spdif with Gefen Cat5 extender?

[jbpsrca]

Hi folks,

 

My PC-XP music server is 70ft from listening room audio equipment. I want to switch from current squeezebox setup, to using Media Monkey direct from server to DAC. Objective is optimal sound quality, with better software interface / responsiveness.

 

Current DAC is Bel Canto 2 (w spdif (coax or toslink)). Future DAC (6 months / year +) targeting Bereley Alpha or similar high end.

 

Considering 2 choices for bridging that 70ft from server to DAC:

 

Option 1: Install a Lynx 16AES card in Music server, with a custom 70ft AES cable terminated HD26 to AES. Connect to current spdif DAC with Neutriks AES to spdif transformer.

 

Option 2: Install a best quality spdif IO Card (ESI @ Julia?), and bridge a short TOSLink cable at each device with a 70ft CAT5 cable connected with Gefen CAT5 spdif extension transformers.

 

Both options seem rated for this distance on paper. But I am unable to decipher to specs to determine which option offers the fewest compromises, injects the fewest jitter problems, etc.

 

Seems there are concerns in this forum with longer AES cables?

Seems like the Gefen solution is recommended in this forum for its conenience, but hasn't been tested for optimized performance with a good spdif card (if there is such a thing?)

If a long AES cable works, will the Neutriks spdif transformer trash it all at the end?

 

Any thoughts or other recommendations welcome!

 

 

[DSD_mastering]

You can go either of several ways. Out computer room is 70 - 100 feet away, depending on which room your in. Our video machines have Lynx cards in them and have no problem at all with AES/EBU signals up to 100ft. No transformers required. These were custom cables by Redco.com

 

Another direction you can go is the RME MADI cards. MADI will let you go hundreds of feet with no problem.

 

We use NTI and Gefen CAT5e extenders for all our DVI, VGA, USB, FW and KVM switches without a problem.

 

 

Regards,

 

 

[tmfidelis]

Dear jbpsca:

 

The solution does not address your objective to achieve optimal sound quality, fyi. Relocating the computer next to the DAC will minimize reflections and reduce environmental noise entering into the equalization. By the time one purchases extremely well built wire, one can build a silent PC and control it via wired Remote Desktop.

 

Again, I am focusing on the words "optimal sound quality".

 

Regards,

 

Tim Marutani

Emeryville, CA

 

[bordin]

Hi folks,

 

I got my AES16e a few weeks ago and had a chance to build a DIY AES-2-SPDIF adapter.

 

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My playback machine is located across the room. So, I made a 16-ft AES/EBU cable, using Belden 1800B bulk and 2 XLR plugs, for extending the Lynx breakout cable . The result at the converted end through my DIY AES-2-SPDIF adapter is excellent. Only there is 24 ns delay, but the waveform is still perfect.

 

Ch1 (yellow) was measured at the end of the 6-ft breakout cable, and Ch2 (blue) was at 22 feet. The value of 3.3 Vpp of AES/EBU was converted to 0.758 Vpp S/PDIF (in 192k testing).

 

 

From listening tests, there is no degradation in the sonics. The Lynx still sounds fantastic over the 22-ft distance.

 

 

The S/PDIF output of my Juli@ sounds similar to the signals of my M-Audio Audiophile USB, Firewire Solo and my friend's Asus Xonar HDAV 1.3.

 

IMHO, the AES16e card is another class of a digital transport for music playback, at least, as good as quality CD transports, such as C.E.C. TL2 that I've auditioned in my system with my OMZ DAC/PREAMP & X-2 cables. The sonics is very musical, particularly *very* well balanced and more detailed.

 

Once you hear the AES16's in your system, I don't think you would go back to any cheaper audio interface devices. This also made me realized that some unpleasing sounds in the system is because of the transport, not the DAC ! Many people don't pay much attention on the transport part. It's really worth investment ! TOSLink connection is typically inferior to AES or S/PDIF, sound-wise.

 

Regarding active signal converters, I'm doubtful about accuracy of the conversion process, given the Lyxn's output (clocking) is very precise already.

 

[jbpsrca]

Great posts, folks. Helps alot.

 

Bordin, thanks for the details of your recent project, and comparisons of the Lynx AES to the spdif route. I'm liking what you did, ad I'm leaning that route. Bruce, thanks for the real life experience in the studio with all these options. As always, great resources with helpful, pertinent info in this forum.

 

Tim, thanks for the suggestion for the cost effectiveness of a local silent PC. That is a good option, but I also want to maintain my vinyl ripping studio (only 2,000 more albums to go!!!) at my current server location, and I'd prefer not to build a 2nd music server ( I geek all day at work, and want to minimize my geek footprint at home, if I can). I do appreciate the concerns about the cables, but:

1. I don't understand reflections as a problem in a long AES cable. I thought reflections were only a problem in too short optic cables?

2. I don't see a proper AES cable subject to environmental noise, nor it having an impact on a digital signal within the cable, as long as the cable is operating within specs.

Am I missing something here? I would think Bob, in a heavily equipped studio environment, would be suffering from such environmental noise, if that were the case (for analog audio cables, I can see the signal being much more sensitive to environmental influences)

 

Cheers!

 

 

 

[Happy]

All

 

I decided to make a Synchronous system - that is to say Lynx output clocked to the Alpha DAC (as opposed to an async system e.g. firewire DAC).

 

If you assume that the playback system Amarra and Itunes output the correct samples at the correct time then the engineering of the system is heavily influence by the clock distribution. The clock distribution will be affected by the cables/impedences and crosstalk/emc etc..

 

I especially wanted to remove the influence of a very electrically noisy computer.

 

So I tried the following setup: Macpro -> Lynx PCIe _> cheap cable (long cable) -> Antelope DA reclocker -> very good cable (2ft) -> Alpha DAC.

 

I am delighted with the results - Much wider sound stage, much better separation.

 

I then tested a benchmark DAC (in place of the Alpha) again very good results. The difference between the Benchmarkk without the Reclocker and with the reclocker is very apparent - the difference for the Alpha DAC more sutle.

 

I also noted that before the reclocker the system would improve over time - as things warmed up - sometimes as long as 2 hours. With the reclocker the system works very well out of the gate.

 

I mention this because this may solve your cable problem - with the reclocker the ingress signal can jitter quite a lot - much less dependence on the cable length and any impedance mismatches.

 

Note: I have no affiliation whatsoever with any equipment companies etc...

 

The reclocker has the advantage of 'following' the output rate - so if Amarra plays a 192khz signal the reclocker will lock on to the new signal - this is different from clocking the Lynx card directly which would require manually changing the clock if sample rates of the song are different.

 

Regards

/Paul

 

 

[jbpsrca]

Excellent suggestion. I'm following your other Antelope DA thread with great interest.

 

This device seems to have the added short term advantage for me of:

1. running a long AES cable from the Lynx to the Antelope (sounds like Wild Kingdom, here ;-)

2. using the Antelope to convert AES in to a short spdif out cable to my current Bel Canto DAC (which only has spdif input). If the Antelope handle this format conversion as well as re-clocking all in one box (as it seems to do), then its a true winner for me right now.

 

Thanks!

 

 

 

[Happy]

jbpsrca

 

I just did a quick test - AES into the DA then SPDIF out - the DA doesn't seem to reclock to both "thru" ports - sorry about that. Other reclockers may. Alternatively one would need an AES to spdif conversion just before the DA - happily the impedance mismatch shouldn't provide a problem given the reclocking thats about to happen.

 

Best of luck

 

/Paul

 

[vortecjr]

Im going to pick and choose what things to comment on since I'm comming late on this.

 

A custom 70ft AES cable terminated HD26 to AES does not really bother me. Converting it at the last minute and connecting it a spdif DAC does. I could be way off, but the unused cable in that conversion acts like a 70 antenna that dumps whatever back to your source! I guess I don't like the odds of that being any good....hehehe. I looked at a bunch of these AES to spdif units. The Neutriks adapters (my terminology because it does not convert the digital signal) are not really designed for a true adaptation. Only one actually has the ohm correction and voltage correction and you need both. Take a look at this short post and my comments:

http://www.computeraudiophile.com/content/Computer-PS-Audio-DAC-III

I understand the temptation (I was also tempted) to use the aes16 card and then adapt to spdif with something, but it really defeats the optimized design of the card. I'll leave it to other to comment on the Gefen...

 

Tim, I agree!

 

Bordin, can you tell us some more on why the two square waves don't look the same? It appears like you have an improvement on the square wave. I'm I looking at it right?

 

Paul, wow you most be like on stage with the band....hehehe. Post some pics of the room it sounds interesting!

 

Regards

 

Jesus R

www.sonore.us

 

[bordin]

Hi Jesus,

 

To my knownledge, every electrical transmission line acts like your plastic pipe that can absorb vibration from the water pump and maintain a contant pressure level at the opening end for sprinkling your lawn.

 

The yellow waveform seems to have some interference. It was measured at the connection at the end of Lynx's breakout cable . So, a good cable must "dilute" noise. I guess the 16-ft cable acts like a passive regulating device (with certain LRC characteristics) for signal transmission.

 

[vortecjr]

thanks and post the name of the software/scope when you have a chance....

 

Jesus R

www.sonore.us

 

[bordin]

Jesus, I got this one 10 years ago, the first budget DPO in the market.

 

 

 

You can use any digital storage oscilloscope or a PC-based oscilloscope. Google can help. ;-)

 

[machinehead]

Hi Bruce,

 

I took a look at Redco products, nice stuff.

 

Do you use their speaker wire as well for your studio? If not what brand do you use?

 

Thanks,

 

Jeff

 

[DSD_mastering]

My whole studio is wired with JPS Labs Aluminata/SC3 (in-wall, interconnects and speaker)The only thing that JPS doesn't do are the DB25/26 cables. Those I get done at Redco with Mogami Gold.

 

 

Regards,

 

[machinehead]

Wow! that is pricey cable! You must have more in cable than my house is worth!

 

Could you comment on what percentage high end cables affect sound vs. good quality cables?

 

Thanks,

 

Jeff

 

[DSD_mastering]

Hi-end cable such as Transparent and MIT with their network boxes really messes with the sound... IMHO.

Really good quality cable such as JPS, Cardas, Kimber and such really does a good job with opening up the sound of a system. Yes.. system.. it's all about synergy. Some cables don't work with some systems.. especially systems that use proprietary engineering like CAST from Krell or DartZeel.

You put a good power cable in your system... you "might" hear a difference... You replace every cable in your system with the same brand good cable and it is noticeable. It's all cumulative.

The difference between $100/ft. cable and $1000/ft. is that last !% of euphoria.

 

 

Regards,

 

 

[The Computer Audiophile]

If anyone is still interested in the Gefen extender I reviewed one of them here http://www.computeraudiophile.com/Gefen-Digital-Audio-Extender-Review

 

[aps]

Jbpsrca

 

How do this project work out? I've got a similar challenge and am interested in your feedback.

 

Cheers,

APS

 

[jbpsrca]

It worked GREAT! Just got it hooked up and sorted out last night, for the first time - and it was phenomenal.

 

I ran the 70ft Redco made Gotham cable straight to my Berkely DAC for a few days. It worked OK, but sound quality was not as "magical" as I had heard the Berkeley DAC in another system. And then the playback started to skip, fuzz, static, and all sorts of other obscene sounds intermittently.

 

Then I plugged the 70ft cable into the Antelope DA, and a 1m Harmonic Technologies Digital Magic 1 cable from the Antelope to the Berkeley - and it was AMAZING!

 

Completely stable playback, no digital artifacts. And the sonic quality leapt forward exponentially - rich, vibrant, detailed, pristine - truly a phenomenal sound. Produced more out of the Berkeley than I even thought capable - based on my listenings at previous demos - and I came in with VERY high expectations.

 

This was a home run solution for me - no doubt about it.

 

[aps]

Jbpsrca

 

Thanks for the feedback. It sounds like a very good result and another option to consider given my remote server.

 

APS