[michaelconnor]

Okay, I'm currently using the AV710's Wolfson DAC, and for the most part I've been pretty happy with it. However, I'm going to be upgrading my amp (pa2v2) pretty soon and was thinking about getting Headroom's Micro Stack. My question is, would it be worth it to upgrade to the Micro DAC and use the Chaintech's SPDIF? $270 isn't pocket change, and the Wolfson isn't terrible. Is a dedicated DAC really worth the difference? Or should I just go with a new amp?

 

[AdamWill]

I did a similar upgrade (AV710 to Firestone Spitfire) and there's a definite difference. It's not like going from ipod buds to decent headphones, but it's not difficult to notice either.

 

[grandenigma1]

the microstack is a very fine setup. I have both and the microdac has better detail and clarity. I would certainly recommend it.

 

[michaelconnor]

Thanks for the advice. Are either of you using USB? or is SPDIF the way to go?

 

[grandenigma1]

Ive never used USB as I find it limiting in bandwidth.

 

[AdamWill]

Spitfire doesn't have a USB input, so I use optical. Given you have the AV710 already I'd probably go optical if I were you (apparently most DACs with a USB input convert the USB signal to S/PDIF internally prior to decoding it, so that's a 'longer' signal path) but I really doubt it makes a significant different below 48KHz.

 

[Revliskciuq]

The Spitfire is a great DAC, especially when paired with the optional PSU - but it still sounds great on its own.

My problem with the Micro DAC is that can't decide if it's a portable or a desktop solution. While it can be powered by 9-volt batteries, they'll only last you 9 hours, and honestly - who is going to battery operate a DAC like that on an airplane or a train or what have you? Not to mention the lack of RCA outputs.

That being said the Micro DAC does sound really good (it's very detailed), and it comes with an AC adaptor. So if you don't mind the lack of RCA cables, and like its sound (Headroom has a money back guarantee - so you can send it back), then it might be for you.

Personally though, I for $376 shipped, the Spitfire + Supplier PSU was the best deal for me.

 

[AdamWill]

Sorry to hijack the thread, but rev, what kind of difference do you perceive the Supplier making with the Spitfire? Have you tried A/Bing (blind would be great...) with and without it? I'm trying to decide if it's a worthwhile upgrade...

 

[kyrie]

Quote:

Ive never used USB as I find it limiting in bandwidth.

In truth, S/PDIF (24 bit, 48 kHz max = 144 kbps) has much lower bandwidth than USB (up to 12 Mbps = 12,000 kbps). Of course, this does not translate directly, as a USB signal carries more than just audio information, and data streaming through USB is variable bandwidth while S/PDIF is constant for any given task. But USB surely has no bandwidth problems, considering that S/PDIF information requires less than 1/80 of USB's maximum bandwidth. Even for more typical USB data bandwidths, about 1.5 Mbps = 1500 kbps, this is more than ten times the necessary bandwidth for S/PDIF.

 

[Revliskciuq]

Quote:

Originally Posted by grandenigma1 Ive never used USB as I find it limiting in bandwidth.

I use the M-Audio Transport for bit-pefect optical output, and it's capable of 24-bit 96Khz, how much more do you need?

Quote:

Sorry to hijack the thread, but rev, what kind of difference do you perceive the Supplier making with the Spitfire? Have you tried A/Bing (blind would be great...) with and without it? I'm trying to decide if it's a worthwhile upgrade...

I haven't done a blind A/B, but I found the difference to be quite noticable just by doing some informal switching between stock and deidcated PSU's. Particularly the bass response was deeper and more controlled, and the highs were also more detailed but less fatiguing.

I'm probobly going to do a review on the combo sometime next week, once I actually get around to some blind testing.

 

[AdamWill]

kyrie: I'm fairly sure your numbers are completely wrong. First, S/PDIF isn't limited to 48 / 24, AFAIK: you can go well above 48KHz sampling on an optical or coax connection. Second, I think you're wrong on the bandwidth required for the signal. All other accounts I've read state that USB 1.1 is limited to 48 / 16 because that saturates the bandwidth it has available; you'd need a USB 2.0 DAC to go above 48 / 16.

 

[philly4]

Quote:

Originally Posted by kyrie In truth, S/PDIF (24 bit, 48 kHz max = 144 kbps) has much lower bandwidth than USB (up to 12 Mbps = 12,000 kbps). Of course, this does not translate directly, as a USB signal carries more than just audio information, and data streaming through USB is variable bandwidth while S/PDIF is constant for any given task. But USB surely has no bandwidth problems, considering that S/PDIF information requires less than 1/80 of USB's maximum bandwidth. Even for more typical USB data bandwidths, about 1.5 Mbps = 1500 kbps, this is more than ten times the necessary bandwidth for S/PDIF.

Yeah, the math is pretty bad, but the main point is true. SPDIF sends 32 bits for every sample. For 24 bit 48 kHz,that's : 32bits * 2 channels * 48 k samples = 3.072 Mbps (megabits per second, I think you also confused bits with bites above), well within USB capabilities advertised capabilities. Not sure how things actually play out in real world situations.

http://www.epanorama.net/documents/audio/spdif.html

 

[michaelconnor]

I'd be interested to see the opinions of "usb/spdif DAC" designers on this issue. Surely they would have considered the source issue or tested for differences at some point, right?