A little update. Since I am out of 2622's and orders have been light, I have had some time to get some more console work done.
I just ordered the 2nd Rev of the input channel PCB's. I added a copper pour to the bottom in addition to the top. I also was careful to get a ground trace between all signal traces to try and help with crosstalk, noise and the like. I had to rearrange the post fader booster circuit since I was not able to achieve complete "offness" with the FET shunts previously. All is good now and will completely kill a +29dB signal applied to the input of the channel.
I changed a few of the board to board connections from 3M headers to jumper wires with a shield. It will take a little more work when assembling but will be better all around for many other reasons. I also removed the insert receiver amp (which was a DTO5) and dropped in an INA137. The left PCB does not have very much room for anything tall and this helped a lot with layout. I also had to add a cutout for the 2623-1 on the left PCB. The leads on the current versions are a heavier gauge than the previous ones so I need the clearance. I put the discrete followers on the main PCB instead of the small DF plug-in PCB's. This also helps with overall layout. I changed the format of the 2 relay PCB's to be the same as the ones used on the right PCB. This will help keep different parts count down as well as cost.
I have also got a sample order in with the factory for the dual BI pots. I have a center detent version coming for pan and a concentric shaft version coming for the aux sends. These are a 9mm version so much smaller than the previous 51 series Bourns. Besides being smaller, they are way less costly which will help a lot in the long run. The thing I miss most about the Bourns is the bracket option. With the BI's, I had to add some small Keystone L-brackets to secure the PCB's to the faceplate which was very tricky as there is really no room. I was able to make it work and actually fit right in with the front panel artwork.
I also ordered the 2nd Rev of the fader bucket backplane as well as the input channel backplane. I improved the overall console grounding scheme along with changing one or two gold finger/card edge connections. Nothing major but it had to be done and required another Rev.
Next up will be the 2nd Rev of the input channel fader PCB. Super simple but needs a few changes. Mainly an 8 pin pico connector to make the mute group switch a quick and easy install.
BTW, as the input channel sits right now, it has headroom of +29dB from input to output. That I am very happy with!
That's it for right now!
Cheers, Jeff
