Hi there!
And...this thing working wery nice!
Each channel have:
Line pre-amplifier (discrete),input trafo;
Gain Elma 11 pos (not shown), pot instead on pict;
Lo 15-800/hi 700-27k 12 db/oct cuts, switchable(relay);
Phase, insert (relay switchable);
Full para EQ 4 bands, bell/shelve lo/hi, S@ntec-kinda stuff
(opa 2604- filters, discrete-sum ckt), gain;freq;q;+/-6/12/off switch;
relay bypass; relay solo/mute assign;
4 aux busses, mix b (or stereo aux buss),P&G faders, fader booster - discrete, threee busses option switching on each channel(2x actives and 1x passive) and some fun facilities....
+/-24v and 4 layer pcb... DEAD quiet gnd layout, >110 db kill on fader/
~=92 db kill on aux min position, and headroom of +/-24v..
as well as all dc servo(I used +/-15v local stab. and ad706)/big blocking caps option...
Sound? GREAT. Without my impressions of man who built it - but friends
ears impressions....
PCB
Close-ups
The smoke is from pipe, not from channel .
Sweepin' EQ from cheap oscillator (scope in x-y sync'd with osc.)
Distortion on analyzer comes from oscillator. Channel measured
0.004% _total_ dist. @ 1k, 0.008% @10k, and 0.02 @ 15Hz(+4 dB input)
on clead sin. oscillator. Squarewave 40K VERY slight overshoot
from input trafo.
And...this thing working wery nice!
Each channel have:
Line pre-amplifier (discrete),input trafo;
Gain Elma 11 pos (not shown), pot instead on pict;
Lo 15-800/hi 700-27k 12 db/oct cuts, switchable(relay);
Phase, insert (relay switchable);
Full para EQ 4 bands, bell/shelve lo/hi, S@ntec-kinda stuff
(opa 2604- filters, discrete-sum ckt), gain;freq;q;+/-6/12/off switch;
relay bypass; relay solo/mute assign;
4 aux busses, mix b (or stereo aux buss),P&G faders, fader booster - discrete, threee busses option switching on each channel(2x actives and 1x passive) and some fun facilities....
+/-24v and 4 layer pcb... DEAD quiet gnd layout, >110 db kill on fader/
~=92 db kill on aux min position, and headroom of +/-24v..
as well as all dc servo(I used +/-15v local stab. and ad706)/big blocking caps option...
Sound? GREAT. Without my impressions of man who built it - but friends
ears impressions....
PCB
Close-ups
The smoke is from pipe, not from channel .
Sweepin' EQ from cheap oscillator (scope in x-y sync'd with osc.)
Distortion on analyzer comes from oscillator. Channel measured
0.004% _total_ dist. @ 1k, 0.008% @10k, and 0.02 @ 15Hz(+4 dB input)
on clead sin. oscillator. Squarewave 40K VERY slight overshoot
from input trafo.