[cloudbaseracer]

I am looking to find a way to take several digital sources (at least 2) and have them switched into a single digital output.  I found several units:

http://www.inday.com/da4x/da4x.htm     ---    192Khz

http://www.gefen.com/kvm/dproduct.jsp?prod_id=2616 ----  I realize this unit is 96Khz

I am wondering if there is anything I should look for between units?  What would keep the signal the purist from source thru the unit and to the output?  Stupid question but  "is digital digital"? If it is not converting to analog can one unit have more effect than another? 

Any other units I should look at?


James

[Rich Carlson]

I had the Inday and wasn't happy with it - flimsy construction and flaky switching, eventually crapped out altogether.  The Gefen is better built, though it doesn't have as many inputs. 

[richidoo]

Here's a nice one for only $550. It's the only pro quality unit I could find.
http://www.rdlnet.com/product.php?page=449

All the consumer type switches only seem to have toslink optical. If that's what you need, then maybe this: http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=180-980   but it looks junky.

But if your sources are coax output, you will incur additional jitter by converting to toslink and back, probably even more through the cheap switcher.

Ideally you would maintain 75ohm impedance throughout the switcher, low jitter design. Depends what you wanna spend, how good you want it to sound. Jitter is audible. Quality cables help too.

Rich

[cloudbaseracer]

I should have stated that I am in fact looking for coax input.  It would be great to have a unit that is remote controlled as well.

The Gefen is definitely more cost effective than the RDL and as I only need 2 inputs may be the best purchase given Rich's experience with the Inday.

Essentially what I am trying to do is to get the digital signal from my Motorola/Comcast box as well as the digital signal from a Squeezebox Duet to go into my Berhinger DCX2496 which has been converted to accept and maintain a digital source all the way through.

So, jitter will/can occur even if it the signal is not converted to analog at any time?

James
 

[richidoo]

The cable box and SB have optical outs but the DCX needs coax.  Better to stick with coax for all.

Jitter can be created at any point along the digital path. It's the timing variation between individual bits. Very, very slight differences can be perceived. The math is hard to believe that we can hear a trillionth of a second, but it is true (or something is true - the differences are audible when jitter reduction techniques are used.)  Toslink transceivers add it. Non standard connections which are not 75 ohms can cause the standard transceivers to add jitter. Even cable connectors (RCA) do not meet the spdif spec and add jitter. Unless you are prepared to weed it out at every step, might as well not worry about it - just enjoy the show!  Cable audio is compressed anyway, which is more distortion than jitter. SB is relatively low jitter for consumer gear, depending on the file quality you play. Jitter free playback is expensive. The new Bryston CDP is one of the best examples of state of the art in jitter reduction.

http://forums.avguide.com/viewtopic.php?p=9441&sid=d63fc12a4dec9842ff89f09673ada7b3
http://www.stereophile.com/features/368/
http://www.stereophile.com/reference/193jitter/
http://www.audiocraftersguild.com/AandE/npt.on.jitter2.htm
March 2008 TAS magazine, Jitter article by Robert Harley
Google for more if you can stand it... haha
Rich

[cloudbaseracer]

Actually, I will be running with the digital outs on these units.

Oddly enough, today, I connected the Comcast digital out into my Berhinger and it made a weird ticking type sound and the tv audio did not come through.  Not sure what this is about. Isn't it a true digital out? Due to having no switcher I had just been turning up the speakers on the plasma when watching Comcast programming.  I just assumed that the digital out would work.  In fact, I am pretty sure I had it going into the Berhinger about 5 weeks ago before I sent the Berhinger DCX off to have the digital output board installed.  Not sure what is going on here?

James

The cable box and SB have optical outs but the DCX needs coax.  Better to stick with coax for all.

Jitter can be created at any point along the digital path. It's the timing variation between individual bits. Very, very slight differences can be perceived. The math is hard to believe that we can hear a trillionth of a second, but it is true (or something is true - the differences are audible when jitter reduction techniques are used.)  Toslink transceivers add it. Non standard connections which are not 75 ohms can cause the standard transceivers to add jitter. Even cable connectors (RCA) do not meet the spdif spec and add jitter. Unless you are prepared to weed it out at every step, might as well not worry about it - just enjoy the show!  Cable audio is compressed anyway, which is more distortion than jitter. SB is relatively low jitter for consumer gear, depending on the file quality you play. Jitter free playback is expensive. The new Bryston CDP is one of the best examples of state of the art in jitter reduction.

http://forums.avguide.com/viewtopic.php?p=9441&sid=d63fc12a4dec9842ff89f09673ada7b3
http://www.stereophile.com/features/368/
http://www.stereophile.com/reference/193jitter/
http://www.audiocraftersguild.com/AandE/npt.on.jitter2.htm
March 2008 TAS magazine, Jitter article by Robert Harley
Google for more if you can stand it... haha
Rich

[mgalusha]

I don't know if it's an option but if the comcast box allows you to select the digital output format make sure it's PCM 2.0 and not some type of dolby digital encoding. The DCX can only digest standard pcm encoding.

[cloudbaseracer]

I don't know if it's an option but if the comcast box allows you to select the digital output format make sure it's PCM 2.0 and not some type of dolby digital encoding. The DCX can only digest standard pcm encoding.

Stopped by Comcast today and the guy there called some other guy cause they don't do technical out of this really big facility they are in???? Anyway, the guy on the other end said no PCM.  This sucks!! I feel I will not be able to listen to any output other than Audio through the CS2's.

James