DIY Mic Pre Kits, Lunchbox Mic Preamp Kits, Power Supply Kits

used my SC-1's live last night for the first time..as mic pre's in front of a Yamaha M7CL digital console at a 700-seat venue here in SF. In testing them out I made an interesting discovery - when the top panel of the rack case is removed, almost all of the AC hum goes away. When the panel is placed on top of the case, the AC hum gets amplified. (though even cooler is that it's loudest when holding the panel about 1/2" above the case, but not actually touching it.)

i just left the top off (that got some nifty comments) and ended up using it on the kick and snare mics....and got two comments from other engineers about the impact and clarity of the kick and snare - they didn't even know I was using any outboard gear.


but back to the issue - AC hum. I have two ideas here:

first, I could go nuts trying to figure out why it's humming, then develop and implement a solution

secondly, I could just make a plexiglas top panel



discuss

Maybe the top isn't grounded... may need to scrape some paint off to make sure the bottom case and top cover are both grounded properly?

Plexiglass...hmmm... then lit the inside with some blue LEDs....



Curios to what the others said... please do tell.


I think it's the AC transformer that is causing the hum problem... of course, the best solution is move the whole PSU far away from the preamps... i.e. outside the preamp case.

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Well the comments shared a theme - the speed of the preamp - in terms of attack and definition. One engineer assumed I was using two kick drum mics (like a Beta91 inside and a Beta 52 or D6 outside), because of the fatness...but it's just a D6 in the hole and an SC-1.

Same thing with the snare, I was set up with a top and bottom mic, but ultimately just used the top through the SC-1, let it clip just a touch and HOLY CRAP!

I'm going to use it in another live mix tonight.


right now the AC hum is semantics - i'll deal with that, more importantly these things sound amazing. I need two more channels!

oh and....

that external PSU box is where I'm headed...easily the most solution-oriented solution.

I should have the more kits ready by next week.... just need to finish the new Assembly manual and take new photos!

Thanks for the feedback. That's great to hear (no pun intended)!

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so now

i bought a little SKB case to put this thing in...now that it's racked, i don't mind leaving the top panel off. i will probably use a plexi top panel until i decide to go whole hog with the external PSU.

and after another round of trials, my SC-1's were used by the touring engineer for John Doe (from the seminal LA punk band "X")...this was an acoustic show at the Great American Music Hall, and the pres were used on the vocals. Big, warm and detailed - that's how i would describe the sound and feel. No noise issues whatsoever - very, very nice.

Thanks for the feedback! That's great to hear!

Yeah, I would put something on top... at least, to keep the dust out. (and prevent metal objects from being dropped inside)

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