[coolsax]

so I'm going to be using a laptop as source with an HRT Music Streamer II as a USB DAC.  My amp will be about 8 feet or so from the amp, which is where the laptop will be as well.  Would I be better off with a 10+ft USB cable with a short RCA interconnect, so that the DAC is close to the amp or would I better off sound wise with a short USB to the DAC on a shelf next to seating area and then a longer RCA interconnect to the amp.  any thoughts?  Would it make a difference either way ?

[AVnerdguy]

Better to keep the analog connection (RCA cable) as the shorter of the 2 to reduce possible hum issue and you don't need the extra capacitance of the analog wire to reduce hi freq response - although at that length it shouldn't be too much of an isse.

In practice, the USB specification limits the length of a cable between full speed devices to 5 meters (a little under 16 feet 5 inches). For a low speed device the limit is 3 meters (9 feet 10 inches). This should make it in your set up.

[ultrafi]

How 'bout neither?

The USB cable will be the most critical cable in your system; thus, I'd opt for as short a one as possible.  Here capacitance really is at issue because the frequencies are an order of magnitude greater than the highest audio frequencies.  More cable is more reactance. 

I've built a couple hundred USB cables so far, further numbering in variations of more than 40.

I'd figure $100 per foot.  My math tells me 8x$100=$$

Long interconnect; well expense again...$$

How 'bout scoring a iTouch or some such wireless device for remote control...figure a couple hund....

Just my $0.02.

AVnerd, I think you meant to say high speed device?!

[AVnerdguy]

No, actually I copied and pasted directly from www.USB.org site by asking for maximum allowable length of a USB cable.

[ultrafi]

Ah,....with faster - the cable must be shorter.

Try: http://en.wikipedia.org/wiki/Universal_Serial_Bus:

"The maximum length of a standard USB cable (for USB 2.0 or earlier) is 5 metres (16.4 ft).[28] The primary reason for this limit is the maximum allowed round-trip delay of about 1,500 ns. If USB host commands are unanswered by the USB device within the allowed time, the host considers the command lost. When adding USB device response time, delays from the maximum number of hubs added to the delays from connecting cables, the maximum acceptable delay per cable amounts to 26 ns.[28] The USB 2.0 specification requires cable delay to be less than 5.2 ns per meter (192,000 km/s, which is close to the maximum achievable transmission speed for standard copper cable).[29] This allows for a five meter cable. The USB 3.0 standard does not directly specify a maximum cable length, requiring only that all cables meet an electrical specification. For copper wire cabling, some calculations have suggested a maximum length of perhaps 3 m."

[werd]

Ah,....with faster - the cable must be shorter.

Try: http://en.wikipedia.org/wiki/Universal_Serial_Bus:

"The maximum length of a standard USB cable (for USB 2.0 or earlier) is 5 metres (16.4 ft).[28] The primary reason for this limit is the maximum allowed round-trip delay of about 1,500 ns. If USB host commands are unanswered by the USB device within the allowed time, the host considers the command lost. When adding USB device response time, delays from the maximum number of hubs added to the delays from connecting cables, the maximum acceptable delay per cable amounts to 26 ns.[28] The USB 2.0 specification requires cable delay to be less than 5.2 ns per meter (192,000 km/s, which is close to the maximum achievable transmission speed for standard copper cable).[29] This allows for a five meter cable. The USB 3.0 standard does not directly specify a maximum cable length, requiring only that all cables meet an electrical specification. For copper wire cabling, some calculations have suggested a maximum length of perhaps 3 m."

Oddly enough my wireworld usb is 7mtrs.  http://www.wireworldcable.com/products/57.html

I guess the designs allows up to 7mtrs for usb.

[Mike B.]

I run a 10' USB from my computer to the DAC. I did try an experiment by ordering two identical USB cables. Nothing special. Gold plated Chinese mass produced. I sent one to Jena Labs and had them cryo it. there was a noticeable difference for the good with the cryoed cable.

[MerlinWerks]

All good and valid points from a technical perspective, but the bottom line is you will in all likelihood be fine with either way. I do like the wireless touch/phone/tablet as a remote solution the best though 

[coolsax]

thanks for all your suggestions.. I think I will likely try the 3-4 meter USB cable, likely an audioquest forest with a shorter RCA and go from there.. as long as I shouldn't have any degradation of the digital signal over a 10-13 foot span then I think that would be the best option..   I had thought about a squeezebox touch for a shorter distance and using a Itouch as a remote, but I decided on going Laptop b/c it would allow me to surf the net too while during casual listening sessions., 

[ultrafi]

coolsax,

work...likely yes, though maybe not at hi rez....

sound the best, nope...not even close in a decent system.

Sorry; but, I calls like I hears 'em.

HTH

[coolsax]

Well after emailing back and forth with the guys over at HRT I think i've reversed course and will go with a shorter USB and longer RCA,, did the measurements longest rca i'll need is 3 m so not as bad as originally thought.  my system isn't SOTA by any means, just a music hall integrated and Sierra-1s and my main purpose is to just enjoy the music as long as it sounds good to my ears I think I should be fine..