Groove Tubes Model 1 / 2 / 2b 9-pin d-sub cable needed.

[Marc Alan Goodman]

fact. And buy one of those alligator clip trees they sell at radio shack. You'll thank yourself. They're a bitch to work with but at least they minimize burns.

[???????]

First of all, have you swapped sides of the power supply to verify it follows the mic and not the half of the power supply it's plugged into? Have you swapped cables to rule that out?

Assuming the problem definitely follows the mic:

Electrolytic caps won't typically cause white noise like that. However, do replace that 220?f cathode bypass cap, anyhow. If it went high-ESR it could cause a reduction in output and create unwanted stray NFB at certain frequencies, changing the frequency response of the mic. So if that's old and you're having those symptoms, then it's a good candidate for replacement.

What kind of resistors are in the mic? Carbon film? Metal film? Carbon comp?

If they're carbon comp types especially, I'd replace the 220k loading the plate of the first triode. Sometimes resistors in this spot can absorb moisture and the symptom is white noise, usually.

There's not much going on there, so you shouldn't have too much of a problem licking it. Good luck.

[behussey]

Woah, these are more complicated than I thought.
The connectors are standard M/F 9 pin. Locking is nice but I bet they'd hold fine without it as long as you aren't moving the mic around too much. Just be careful with it.

Pins 1,2,3,5,7,and 8 are straight across. Then pin 7 is jumpered to pin 9.

Let me know how the replacements work out, and especially post if you find a source for the locking connectors! I think everyone would appreciate it.

Resurrect old thread...
So I just got a basic 9-pin cable and then saw this post. So all the GT cables have the jumper from pin 7 to 9? I just want to confirm this info before I dissect my new cable. Thanks!

BTW, check out this little guy (it's a GT tube DI, maybe a prototype?):