I use an Apogee USB Mini-Dac with my Mac G4 laptop -- sounds really good for casual listening, using the laptop as a juke box. I rip my CD's to the hard drive uncompressed using AIFF. I had an M-Audio Audiophile USB Dac prior to the Apogee -- the Apogee blows it away. Of course the M-Audio cost $175 while the Apogee cost $976. |
Yes, I'm using the Mini-Dac as a DAC. I'm running USB from the Mac G4 laptop to the Apogee, then balanced XLR interconnects to a pair of Mackie HR824's --- I'm pretty astounded at the quality. I don't know that you need to convert the digital signal from your laptop to PCM in order to run it with your dCS gear. I could be wrong, but I believe you just need to keep it in digital since your dCS gear probably doesn't have a USB input, you need something between your laptop and dCS, something to connect them while keeping the signal in digital. I tried that with an input of a Proceed AVP2 so I could use the DAC in the Proceed. For some reason, it didn't sound that good. Only thing I can figure is that something in the M-Audio piece was degrading the signal somehow. Everything sounded time smeared. I'm going to guess that you could use the Apogee similarly and it would sound way better. I know the Apogee has a better clock/buffer which helps eliminate jitter, so maybe the signal was getting smeared by going through the M-Audio piece even though I didn't use it for DA conversion. When I get some time, I will experiment with the Apogee, connecting to the laptop with USB and taking an SPDiF out of the Apogee to the digital input of the Proceed and see if there's a huge improvement, as I expect, over the M-Audio piece. There may be a less expensive piece that will handle the transer and keep the signal in digital while eliminating jitter and smear for less money -- if there is, I'd like to know about it. In the meantime, I can tell you that the Apogee sounds great in my application. |
Here is something that will take a USB input from your computer and convert it to toslink or SPDiF without performing DA conversion for $79 ----
http://www.computersandmusic.com/xcgi/SoftCart.exe/store1/edirol/ua1a.html?L+mystore1+urub1816+1088598294 |
Oops -- forget that one -- didn't notice that it is the opposite of what I thought. It is for sending digital input INTO your computer using the USB port. Sorry 'bout that. That's what I get for posting before I've had coffee! |
Why do you want to convert to PCM before your DAC? |
Here's the Edirol piece to which Ed is referring. This is the reverse of the piece I posted before, which means it is what I thought the other piece was. It will take a USB connection from your computer and convert it to SPDiF or Toslink, keeping the signal in digital. But, nowhere does it say it converts the signal to PCM. I'm not sure where this is coming from. My understanding is that the computer puts the signal out in digital at whatever resolution you imported it and I don't know that it needs to be "converted" to PCM nor do I see that the Edirol piece performs this function. I'm not sure what the problem with the M-Audio piece wasm either -- but -- I can tell you that when I was running MP3, the pieces in my system were not critical. I could take a feed from the headphone out, split the signal into L & R, feed it into analogue inputs in my pre-amp and you couldn't tell much difference. Now that I import my CD's uncompressed, you can tell large differences between, for example, the M-Audio piece and the Apogee.
http://www.edirol.com/products/info/ua1d.html |
The Waveterminal piece is interesting. It offers sample rate conversion. Maybe this is what is needed to take the signal from the computer to a home audio DAC and maybe that is what was missing from the M-Audio piece. Like Harry, I am no computer expert, I learn as much as I can in order to get the computer to do what I need, but my interest lies far more in music, which is the carrot that leads me to learn about computers. I am curious to find a product that will let me connect the computer to the digital input on my pre-amp so I can use the DAC in the Proceed, so I will be interested in hearing about Harry's experience with the Waveterminal piece. I the meantime, I am getting a real kick out of this G4, Apogee, Mackie system I've built. It is surprisingly accurate, musical, and enjoyable. But, this has opened up a little mystery and now I am curious to know whether uncompressed music files like AIFF need to be converted before they can be read by a home audio DAC and why my Apogee DAC doesn't need any conversion before it can perform its magic. |
Eric -- thanks for the info. Maybe it is even worse -- maybe the M-Audio converted the signal from digital to analogue and back to digital. Whatever it was, the Apogee sounds way better, but I know the Proceed has good DAC's, so I am pretty certain something went wrong inside the M-Audio piece. At some point, I am going to take an SPDiF out of the Apogee into the Proceed to compare them in that capacity. |
You can go from your computer to a Big Ben, You have to go from the computer to a converter that will convert USB to SPDiF. Edirol makes such a unit. Then take SPDiF from the Big Ben to the digital input in your DAC or Pre-Pro.
Computer -- USB -- USB/SPDiF Converter -- SPDiF -- Big Ben -- SPDiF -- DAC or Pre-Pro.
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Looking forward to your report. |
Did you ever get your computer connected to your dCS DAC? |
That's an interesting path to say the least. I count three jitter/clock solutions, a pre-amp, a USB to SPDiF converter, and an upsampler, before another upsampler and DAC. You sure you need all of that? |
>>trust me...it works!!!!<<
I trust you. Most of what we do in an effort to get better sound could be considered extreme and weird. Who am I to judge? |
With an Apogee Mini-dac, you just take a USB feed from your computer. No need for any gear in between. |
>>the apogee is a fine DAC, from all I've heard. But, I don't think it is in the same league as the Hbrandt's $14K dCS stack.<<
I don't mean to suggest that it is, but you can go directly from the computer to the Apogee Mini-Dac via USB, you don't need anything in between. The Apogee Mini-Dac has a Re-clocking solution based on the Big Ben. So, if you use the Apogee to re-clock rather than a Big Ben, you might be able to simplify a little and have less gear between your computer and DAC. I believe the Big Ben and Mini-Dac are similar in cost.
The question is -- if you go digital to the Mini-Dac or Big Ben and Digital out, do they both re-clock the signal --- or do they only reclock if they convert from digital to analog. I don't have the answer to that.
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Okay, I emailed Apogee. The Big Ben will reclock the signal and keep it in digital. The Mini-Dac will not. The Mini-Dac reclocks the signal and then converts it to analog. Afterall, it is a digital to analog converter. |
There are lots of ways to solve that problem -- the technology already exists.
There's nothing stopping you from having a laptop right in front of you, with which you can control volume, select songs, etc.
If your hard drive is part of a home theater, you can use something like a Mac Mini, plug it ito your video display and use a remote mouse to control the volume and select songs from your video display. |
And there are still others. |
