Message Board

I was describing the 312 circuit. I've never done a 325 conversion. What op amp are you using? What input transformer are you using? Looking at the schematic, I'd approach it like this... - remove C3 and R2, and solder shorts in their places. Then jumper pin 7 to COM. - C5 can also be removed or rep...

Interesting find! I have a few comments... AFAIK, Melcor got into the calculator business a long time ago, dropped their audio line, and never looked back. API (with ex-Melcor employees) kept making compatible stuff. From about 1970 until maybe a decade later I guess, API 312, 325 cards and 550 EQs ...

is there a sonic difference in say one brand of 2N2222 and another. I know theres a hell of alot of difference in tubes, do the same rules apply? IMHO, the answer is sometimes. TONS of different devices have been labeled with the 2222 spec, so in this case the answer is undoubtedly yes. A transisto...

Dropping one leg of a balanced output equates to a 6dB loss. I forgot about ADATs with RCA ins. Thanks for the report! Seems like I've got a few good possibilities here.

there's no such thing as +4dB/-10dB it's all in your (our) heads. he can use any pre, just turn down the gain I beg your padon. What dB spec are you talking about? In my post I said -10dBV as opposed to +4dBu. That's 0.316 volts RMS compared to 1.228V. There's a big difference. This is the nominal ...

Blue Tube looks like a good candidate. Wish it did'nt have that drive control, though. Thanks!

I was looking at the DMP3 but got the impression it's +4 out. Have you ran it into consumer input gear with good results? Not too much level?

If the lid is still off would you mind posting the model number of that Jensen output transformer? "JT-XXX-XX" or "RE-XXX", etc. I'd really appreciate it. Thanks!

Yes, I have UTFSF. A talented, yet technologically challanged relative of mine needs a pair of mic pres for recording grand piano direct to consumer CD-R or cassette via -10dBV RCA inputs. Phantom power is a must. Sure, I could rig up something to pad the outputs of a +4dBu balanced device, but I'd ...

Can't speak for the Trident, but the X73i is the worst mic pre I have ever heard. I'd even prefer Behringer. No, I'm not joking. It sounds absolutely nothing like the Neve that it copies.

I solder PCBs all day, every with a temp contol station and 63/37 solder. I too find myself working at 700degrees F for just about everything, but make an effort to work lower, say between 625 and 650, whenever possible. Ideally there is a eutectic temperature for the best joints that is 600somethin...

Speaking from experience, the problem is that when you're really rockin' out hard and getting into the playing you start hitting every piece of the kit with equal fury, forgetting that most of the cymbals require far less energy to project at the same power as the drums. Inexperienced players, when ...

I think soundguy is working 7 days/week on some new records. No time for messageboards or building gear.

Welcome Brian!

Oh, I think I know which ADM module you're talking about. I recapped some of those before. The exact same Sprague caps are still available new, the TE series. Cheapest at Alliedelec.com, otherwise try Mouser.com or Newark.com. Xicons suck, IMHO. My favorite are the BC AML 138 series of axial caps fo...

The OPA604s are the makeup gain amps. Yes, they are active devices and do require power, but the power connections are implied and have been omitted from the schematic for simplicity's sake. The term "passive mixer" refers to voltage summing. The signal voltages from each line input are being passiv...