Built another preamp, see circuit:
http://sound.westhost.com/project13.htmI made the figure 2 modified version for 12 Volt, point to point soldering, fit it into a small box and power it with an 'external' 9 Volt battery, see below.
OK, it is not a beauty, I had bought cheap parts in a local shop in Thailand, but it works that well that I plan on building one more once I find a nice metal box. It made lots of fun to build and really is very noise free.
Of course I made two circuits to have stereo and added a 9 Volt plug-in power supply. I simply terminated it with two stereo mini females, one for Mic-in, one for 'out', one power switch, one pot for gain control and one switch to turn on/off mic in power supply ( as the AT822 does not, but the Giant Squids and the coming CMC4s want the 9 Volts )
With the AT822 no noise at all noticable, but with the Giant Squids there is some noise.
However I wonder if I had better changed some values of resistors to optimize it for 9 Volts, but I do not know how to calculate them. For the mic-in power I used 6,8 kOhm Res. and 22uF Caps and though it works I am not sure if their value could better be changed.
Anybody here who can answer this questions?
I asked them here:
http://sound.westhost.com/phpBB2/viewtopic.php?t=1086 ( answer 3, username kuuan ) but there are no answers yet.
If you only consider ballanced see:
http://sound.westhost.com/project66.htma simple unballanced to ballanced solution:
http://www.fivefish.net/diy/balanced2/default.htm resp.
http://www.fivefish.net/diy/balanced/default.htmto understand ballanced:
http://www.tangible-technology.com/power/Phantom_Power_connect.htmlmixers:
http://www.aaroncake.net/circuits/mixer2.htmhttp://home.maine.rr.com/randylinscott/may20.htmhttp://sound.westhost.com/project94.htm ( this one I really would like to build, but have many questions - which I posted at the forum of that site in section 'preamp', but no replies yet - somebody here will check it out? )
linkpools:
http://www.izatech.ro/linkuriaudio.htmhttp://www.epanorama.net/http://