Hey folks,

Quick question today- I want to know whether hooking up the following will result in good sound quality or is a sound hook-up method in theory.

The device in question is:
http://www.edirol.net/products/en/SC-D70

It's a synth and digital external sound card in one.

Basically, I'm going to hook analog components (analog synths) to it, or to a mixer and then to it, and I wanted to know if it was a good idea (i.e. hook analog audio sources to the mixer->sound card or sound card via RCA cables and then output digital audio via USB to PC).

Previously, I had the stand-alone non-sound card version of the synth which comes without digital capabilities (although it can hook directly via USB), the SC-8850.

I wanted to know if I'll get better sound quality by using a digital version and sending to USB.

What ADC/DAC processes would take place? When I hook the analog synths to the analog/digital one, is it analog-analog when I'm hooking RCA-RCA? Does that analog signal get converted to digital when I send it via USB to the PC? Would it be better to hook the analog stuff to an external mixer and then send it to the PC or send it to the sound card directly? Are any of the ADC/DAC processes going to be hramful to my 'bit-perfect' sound (the sound being made by the SC-D70, not the other analog sources)? And so on!



Any thoughts/comments about the above are welcome as always, thanks everyone, I love the time people give me here for my crazy questions.

Regards,
- Spike

I'm a little confused. Which two things are we comparing the audio quality of?

Are you really asking about this?
[Soundcard]-USB-[PC]
vs
[Soundcard]-Pci bus-[PC] ?

I haven't had one of such synths, but i believe they work just like external soundcards, with the added ability to synthetize sounds (and other data).

In other words: What really happens is that the hardware that usually goes into the internal card, is put outside, and instead of communicating with the internal bus, it uses the communications port from which the data is sent to the bus.

Quality-wise there's no difference. At much, one can count the reduced effects or interferences by other parts of the PC (graphics card, hard drive...) as a plus for external soundcard.

Edirol is not a bad brand (afair, it's Roland's second brand) and... well.. probably you already know that

(Ps. got an edirol usb midi keyb here)

Thanks for the responses!

I'll try again, since my first post was kind of confusing:

1. Is there better quality from hooking the synth up to the PC via USB and sending digital audio, instead of say hooking the synth up to a PCI sound card via RCA cables.

2. What ADC/DAC processes would take place?
a. When I hook the analog synths to the analog/digital one (SC-D70), is it analog-analog when I'm hooking RCA (other synths)->RCA (SC-D70)?
b. Does that analog RCA signal inputted into the SC-D70 get converted to digital when I send it via USB to the PC?
c. Would it be better to hook the multiple analog synths to an external mixer with RCA cables and then to the synth/sound card, or send it to the synth/sound card directly (no mixer)?
d. Are any of the ADC/DAC processes (i.e. analog synths signal turned into digital when sent to the PC) going to be harmful to my 'bit-perfect' sound (the sound being made by the SC-D70, not the other analog sources)?


Sorry for the confusing questions- I think it's that I'm not used to digital sound theory and am not very knowledgeable about ADC and DAC processes.

I appreciate the time

Regards,
- Spike

The synth *is* the soundcard. Even simpler: Where do you connect the Speakers?
With this, i mean that using a PCI soundcard would necesarily imply and ADC/DAC process. Using the synth itself doesn't need it. (that, if it doesn't have a digital output)
Ok, I've checked the specs now. The synth has digital inputs and outputs, which means you can connect the synth to another soundcard/amplifier digitally.



Other synth (Analog) ->(Analog) SC-D70 inputs -> (digital) SC-D70 soundcard mixer.

Note that if the other synths support digital output, you could send one digitally to SC-D70. (I've seen it has several inputs it may support several digital inputs. It is not clear from the specs)


Again, USB is just a way to make the soundcard (and midi data) available on the PC, the soundcard is on the synth, and the mixing occurs on the synth.


Depends.. what are you interested in? If you think that converting the sound to digital will degrade it, you can use an hardware mixer, but nowadays, hardware mixers are becoming digital.

Using an external mixer should also provide you with more control over the input, (SC-D70 has several input sources, but you may need more).
If you need to record the whole piece in the PC, you either need to connect everything to SC-D70 (with a mixer, if needed), or use another soundcard and mix everything in the table and the table output to this other soundcard.


"bit-perfect" only has sense when talking about a digitized signal. Analog sound doesn't have "bit-depth", just Signal to Noise Ratio (SNR). SC-D70 most probably is a digital synth, mixed digitally in the SC-D70 soundcard. When you output that in analog to other places, you're adding the SNR of your DAC.
Since it has digital inputs/outputs (as i pointed above), you could send it bit-perfect if the destination hardware supports digital inputs.

[edit: checked specs)