+ Can I record using input 1 and 2 simultaneously as 2 mono tracks or I must use them as a stereo track? With Quad Capture, can I use input 1, 2 and digital input 3/4 at once to record 2 mono and a stereo at the same time (My HD500 has SPDIF output, so I can record 3 sources at once...)?
Yes you can. For 2 ins, it's either 1 or/and 2 mono, or 1+2 stereo. For the Quad Capture, 3rd and 4th ins via SPDIF can be configured the same, either 3 or/and 4 mono, or 3+4 stereo.
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+ Do I need to unplug loud speaker (or headphone) when I want to use the other one? Or both of it work parallel with same volume knob?
One output vol, controlling both monitor speaker output and headphones at the same time. I would switch off my monitor speakers if I monitor via headphones.
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+ Is there anyway to adjust the volume of monitor speakers and headphone separately?
Not via the regular 1+2 outs.
Possible (can't be sure) via SPDIF 3+4 outs, but never tried before.
Edit : I've tried once to send the 1+2 out to a mixer, then to the monitor speakers, this way I can control the monitor vol separately. But I've clean up the setup and I'm not using this configuration anymore.
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+ What about the latency? I'm using Windows 8.1.
Good latency. I get good performance at 44100 sampling rate;
- 64 samples (8.3 msec roundtrip)
- 96 samples (9.8 msec roundtrip)
Depends on your CPU, compared to mine (i7 2600K). Win7 and 8 should be similar.
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+ Can I use Roland Captures as my soundcard? It means the device always connects to my computer. Any problems with the driver when computer is on or off?
Yes, it's powered via USB - most advise to set power to full time. I never set the computer to sleep, so it's either on or shutdown.
Hope this helps.