500 series Aphex lunchbox mods

[standup]

I want to run phantom power to Pin 15 in an Aphex lunchbox, which left pin 15 not connected in Aphex's variant on 500 series modules. The card connector is soldered to the PCB and I'm not sure there's an easy way to run a jumper wire from the 48v power supply. The "feet" of the card, soldered to the board, seem to have the solder running together from pin to pin, and so I assume there's no current passing through.

Any thoughts?

[rhythm ranch]

I know Aphex made a "lunchbox" that worked with the dBX 900 series modules. I've never seen a 500 series box from them. Or... I never realized that 900 series and 500 series boxes were compatible. ???

[standup]

Aphex 4b is a lot like API. I've had 312 modules from Brent Averill in mine, long ago, with no phantom power and otherwise they worked. It took a pin swap on the 312 board, and I don't remember exactly what. Maybe tying pins 7 and 8 together, now that I'm researching it.

Modules that worked in the 4b Aphex lunchbox were the CX1 compressor, EQF eq and a B&B mic pre that I've never seen an example of.

I don't know 900 series stuff, really, and I assume 900 modules wouldn't work in the 4b lunchbox, but that's not based on factual knowledge.

[rhythm ranch]

Cool. You learn something new every day!

[W DeMarco]

Be advised concerning the need for a 48 volt rail on an Aphex 500 series. If you have any Aphex mods its not advisable to run them with a hot pin 15. The CX-1 "500" series compressor uses pin 15 for an external metering output. Run voltage on 15 with that mod plugged in and POW there goes your meter driver. If you do use aphex cx-1 mods and want them in an API rack or an aphex rack with hot 15 you'll need to dremel across 15(on the cx-1) to kill the connection.

[standup]

Thanks, I think I have it worked out OK. There's a jumper wire carrying 48v to two of the slots, and the slots with CX1's in them have no changes to the connector scheme. In this lunchbox there's no jack for the external meter output, so I'm not going to miss that capability.

[W DeMarco]

I'll tell you what, I love our old aphex comps and EQ's. The EQs are real mild with killer filters on both ends. The CX1s are lots of fun as well, strange controls but they make sense after a few uses. Nice to have the gate built into them as well. We have ours in an API rack so had to mod them with the dremmel but I doubt I would ever even want to run an external VU anyways when the metering options are pretty cool to begin with. Have fun!

[Jim Williams]

I just went through 4 CX1's here. All of them had shot el caps. Some with blown output stages. I used 182 and 172 power transistors from On and some National LME opamps. I raised the top end bandwidth and bypassed all but 3 el caps left in the circuit. Those were bypassed with poly films to let the tops out. I added some local psu bypass caps and increased the values of the el psu filter caps.

They are very clear and quiet now, no hiss, great top end transient response, same large Jensen output transformer.