On Mon, 16 Dec 2013, Djého Youn wrote:

thanks for all the answers.

Just in case... are you talking on stage volume or mains volume?

for those who gave advice with main mixer, 'sorry I wasn't that clear. but
mixer's input gain was max. and it was only half on the meter. then boosting
mixer's channel/master only made my sound horribly distorted.

When it is distorted, what does it sound like with headphones? You need to know where the distortion is actually happening... are you turning your computer to max and distorting in there? Are you using a DI box into the mic input? (try it) Or going into a line in... A DI box is more in line with the inputs of a cheaper mixer. Or an "instrument" input may work better than line in.

this looks quite nice...as it's preamp AND soundcard...if soundcard doesn't
make my signal louder, then I can use it as preamp..if I got it right.
http://www.thomann.de/pl/art_usb_dual_tube_pre.htm

does anyone used this with ubuntu 13.10 on modern laptops? a quick web
search shows that it *can* work but have no drivers. 'seems that some people
has troubles with it.

I have one and like it. It has been plug and play as it is USB1.1 compatible. It is 16bit at 44.1 or 48k or the s/pdif is 24bit (I use it as a pre for the s/pdif in my Delta sound card too. It has it's own power supply so the 5volt USB supply is not an issue. I like the sound better than any of the builtin audio cards. It works fine with both pulse and jack. (and ALSA too if it works with the others) I have used it since ubuntu 12.04. The 3.8 kernels had problems with all USB cards. The one thing I found was I needed to turn off the internal card in pulse and also the wifi. The wifi gave me problems with all sound as it grabs too much time once a minute when turned on and once every 5 seconds turned off until rebooted with wifi turned off or unloading the wifi kernel module. Then I could get jack to run with -p64 on my netbook. (I also turn cron off BTW so that SW update stuff never tries to happen) As with all usb cards... it has to have it's own USB port, not shared internally or externally by a hub. I have to use only my right side USB plug and put anything else in the left side. USB mice are pretty bad at generating interupts. I use the rtirq script (lowlatency kernel) and set /etc/default/rtirq line with RTIRQ_NAME_LIST like:

RTIRQ_NAME_LIST="usb3 rtc snd usb i8042"

Where my usb3 is the usb port on it's own irq (my right side plug). This drops all the other usb ports to lower priority.

Of course the next question is... do you also use a USB midi card?

--
Len Ovens
www.ovenwerks.net