Simple DiodeBridge Compressor

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Can someone please tell me if 42tm019 can replace Hammond 107N?
Looking for cheap easy solution
 

Attachments

  • XC-600134-1212477.pdf
    63 KB
thank you Heikki
how much extra Gain is needed for bjt to start working in a proper manner?
best
The depends at what level you need your lowest threshold to be. I think the best solution would be not to connect the 100k resistors to ground but to a small positive voltage. For example put 10k resistor and schottky diode from +15V to ground and this will give you a 0.2V - 0.4V voltage where to connect the 100k resistors.

Can someone please tell me if 42tm019 can replace Hammond 107N?
Looking for cheap easy solution

That transformer has pretty terrible frequency response. I have used similar transformer in a fuzz/octaver pedal where limited frequency response is actually wanted.
 
working on Ms enc dec......
hope to be in the right way
also attached my starting point
best
richi
 

Attachments

  • Rix_MsEncDec.asc.zip
    1.9 KB
  • Mid-side-box-schematic.jpg
    Mid-side-box-schematic.jpg
    26.5 KB
tryed Ms circuit to sum 2 ch into SC...
the sum point, sc input, out vs SC input
just to compare and verify phase shifting
on Nyquist plot i now see same figure but offset in gain as should be
hoping in this way to affect compression as is working in a stereo behavior
so to reduce the energy created by the sum :unsure: o_O
1- not so expert to judge
2- not sure the Ms is right
thanks for your attention
best
richi
 

Attachments

  • sum.png
    sum.png
    164.6 KB
  • sc_in90deg.png
    sc_in90deg.png
    158.3 KB
  • out-VS-Sc-phase.png
    out-VS-Sc-phase.png
    185.4 KB

Here is Oxford turbo mod ON Gssl...
Old story but still interesting... So the behavior should be the same...
 
Also simulating 2x detector in 1x SC....
I m new so I need to do and check all this attempts.. Just to well understand what I m doing and what can happens by modding or adding circuit and components
 
Schematic with all adviced updates
hope everything s fine....
omitted bypass switch, and 2x6 Lorlin for HPF.... directly wired to front panel
for the blend part i m splitting only the positive pole of the signal, for the moment....i ll add a proper line driver when a i get time
best
richi
 

Attachments

  • DsB_signalPath.pdf
    87.6 KB
  • DsB_sidechain.pdf
    70.3 KB
  • DsB_blendAmp.pdf
    38.7 KB
R48 in the signal path... Is 3k3
The side-chain i divided into 2 boards
The first one for opa buffer, hpf and detector, the 2one the controls....
This way you can add a second buffered detector for stereo version, for different tracking mode

The switch sw1 in the side chain can be not wired if you build a stereo unit with one control board

Sw2 and 3 are a double pole switch….. it s autorelease, here I did an error!
Forgot to wire sw3 to ground when not engaged in the pcb , so just wire from switch to ground since the footprint in the pcb is not wired ( the squared one ), and the other 2 have to be reverse wired

For calibration I did this:
Sidechain trim totally Cw
Set meter trim to have needle to zero
Now turn ccw the SC trim till needle goes down... Now set it again to zero rotating cw the same trim
Measuring Cv out i get 0.5mV
hope everythign is fine

Next step i ll try 8 diode as Heikki did in his unit

Best
Richi
 

Attachments

  • DsB48_pcb.zip
    1.1 MB
Sidechian pcb has another error...
100uF in the timing net must be reversed.... When I did Gerber I was using a np cap in kikad! But the schematics were well updated
So the print is wrong for that component... Sorry!
Best
Richi
 
trying to draw a real front panel....
just an attempt.... hope to fit everything inside!:unsure:🧐
 

Attachments

  • Anodizzato-DsB48-frontPanel-v02-2u.pdf
    47.6 KB
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