CGS49: twin wasp filter with bridechamber front pannel

hottlungs · Joined: Feb 16, 2011 Posts: 11 Location: long beach, ca

The Bridechamber pannel has parameters for cv spread and consoidates the amount of cv inputs by using a switch to select positive and negative cv. I am trying to confirm the wiring from the freq cv input to the switch and from the switch to the freq cv pot & pcb(cv+ and -cv). Would i invert using a dpdt wired:

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Any clarification would really help me.

echoer · Joined: Dec 10, 2009 Posts: 40 Location: lawrence, ks

The wiring for this module has me stumped as well. Not only with the "CV Invert" switches but with the "Spread CV" pot as well. I love the Bridechamber panels but I wish there was better documentation when it comes to implementing Scott's modifications. I will keep my eyes on this thread.

echoer · Joined: Dec 10, 2009 Posts: 40 Location: lawrence, ks

Just found some good info on muffwiggler.

http://www.muffwiggler.com/forum/topic-14390.html&highlight=wasp+filter+spread

Haven't tried any of this yet. Still wrapping my head around it...

hottlungs · Joined: Feb 16, 2011 Posts: 11 Location: long beach, ca

I emailed Scott from the bride chamber and he was very helpful. I just forgot to have him elaborate on the switch because i thought i had it running.

"Hi Dan,

Sorry for the lack of documentation on that. You use the switch for the inversion of the CV. The spread pot is an attenuator (100k is good) for the spread jack. From the wiper of the pot, send one wire to CVSN on filter A via a 100k resistor, and one to the junction of the 100k, 2k2 and pin 3 of that TL072 (where the negative CV is going) of filter B. This will apply the spread voltage positively to filter A and negatively to filter B.

Thanks!
Scott Deyo"

hottlungs · Joined: Feb 16, 2011 Posts: 11 Location: long beach, ca

I tried wiring spdt switches to switch between +/- cv. I have not adjusted the trimmers. I am only getting a response from the distortion potentiometers in LP or Notch mode on filters A and B. BP and HP modes are not outputting anything for either filter and the frequency and resonance controls do not affect the sound. I haven't been able to test the cv inputs. I am posting a picture of my wiring diagram

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the picture contains the 9 potentiometers, 2 rotary switches, 2 spdt switches and 7 1/4" jacks from the rear. I have checked the components and made sure that i installed all of the links. photos of the unit to follow.

hottlungs · Joined: Feb 16, 2011 Posts: 11 Location: long beach, ca

Left PCB

Right PCB

Middle PCB
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Bottom Left
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Bottom Middle
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Bottom Right
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Top Left

Top Middle
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Top Right

PANEL AND PCB
I replaced BC547 with 2N3904 and BC557 with 2N3906 which is why the transistors are oriented backwards on the PCB. power supplied by synthesizers.com power supply.

I am only getting a response from the distortion potentiometers in LP or Notch mode on filters A and B. BP and HP modes are not outputting anything for either filter and the frequency and resonance controls do not effect the sound. Any advice is appreciated.

hottlungs · Joined: Feb 16, 2011 Posts: 11 Location: long beach, ca

I took some advice and wired the frequency pots +V and -V instead of +V and Gnd. The filter works fine now. I'm going to experiment with limiting the range of the frequency pots.