Barcus Berry: Model 4000N

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
We use this Barcus Berry piano mic at our church. Since changing out batteries every couple of months is a pain (especially remembering to change before we are in the middle of a service) I want to convert our mic to be phantom powered from our A&H mixer. Has anyone out there done this and can anyone offer some advice/ help? Thanks.
 
Powering the Piano Pickup

Here's a quick way to provide the 9 volts to the mic without modifying it. Get a plug-in transformer at your local thrift store or spring for a new one at Radio Shack that puts out 9 volts. The way to see this is to look at the tiny raised letters on the plastic or read the label where it says, "Input 120v AC -- output 9v..." the miliamps I'm not sure of; I'd guess it'd have to be at least equal to what a fresh or still-alive battery would give you. Beware the AT&T ones from answering machines and cordless phones, which put out AC current. THEN you get the battery tabs -- the little plug thing you connect the battery to -- and find out which wire is + and which is -, and connect the red wire to +, etc. THEN you clip it into the battery compartment of the mic if it has corresponding snap-on terminals, or you fashion a little battery-sized block of wood to hold your rig onto the metal strips the battery would normally have touched. I've used this to power baby monitors and such cheap devices where I didn't want to mess with batteries; as this is a higher end device you depend on for chruch sound, say a prayer and try it having been cautioned to proceed at your own discretion.

Course, the piano has to be somewhere near an outlet, of course...and I'm not certain this might be the quietist power supply...let me know...

Jonathan
 
Okay: remind me to stop using the "clear" key in these windows; it clears everything!

I should have clarified, or said less more efficiently...When you clip the terminal off the end of your wall-wart 9V power supply, you need to determine which wire is positive, using a multi-tester, or a LED voltage tester, or by figuring it out from the info on the wall-wart itself and whatever is left of the wiring you just clipped off. The latter is just a 100K ohm resistor (or so) in series (before or after) an LED where you run your supposed positive voltage into the terminal connected to the smaller (annode?) bit of metal in the LED, not the one that "reaches over" the other one. You could also simply twist the wires to the battery clip leads temprary-like, try it to see if it powers the mic, and reverse the current if it doesn't before actually soldering. Your mic is probably diode-protected against reverse polarity (jamming a battery in backwards), I say PROBABLY, and you should try the guess-and-check method of determining polarity having been, as always, duly warned to proceed at your own risk.

This is fun. I'm starting a new thread of my own RE adding piezo to a guitar with magnetic pickups.
 
Thanks for the info.

I know I can use a "battery eliminator" if there is an outlet near by, but I am looking for a more streamlined solution. I know that operating the mic (the amplifier really) from phantom power has to be a doable thing -Barcus now sells a version that does this - but what is involved?

My first thought is simply to use an LM317 regulator trimmed for 9V, but what is the interface to get the phantom power safely from the XLR to the regluator?
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.