telephone mic

bradb · May 6, 2005

Has anyone tried to make a microphone out of the earpiece or mouthpice of a standard analog telepone. I'm looking at the www.placidaudio.com copperphone as a guiding template for my direction. I used to just plug the earpiece into a DI, but now I'd like to go XLR into various mic pre's for coloration and put the whole package into a nice container. Any ideas?

BYacey · May 6, 2005

The earpieces are typically low impedance, so a typical direct box might not be the best way to couple this to a preamp. a 1:1 xfrmr or even direct to pin 2 and 3 might be a better way to go. You really are going for radical coloration, aren't you?

pucho812 · May 6, 2005

they want 250.00 for that thing... crazy. IMO not worth it to much of an effect as opposed to useful.

bradb · May 6, 2005

I just wired up 2 ear pieces I have in my possession.. pins 2 and 3 direct to my Hamptone tube pre.

The first ear piece is from a standard, generic beige phone. It's got 7 holes in the front on the capsule and its pretty much all metal, ITT stamped on the back. This one has a higher fidelity sound.

The second earpiece I have is from a more modern phone, all plastic with an exposed coil, this one sounds much more like what I'm looking for... a little darker and more obviously band-limited.

The copperphone has a profit margin, but there's alot of work going into that thing plus materials. 10' of copper pipe is $44 (here in NYC), copper endcaps are $5 each, and they don't come polished or drilled either. The guy who makes it is the bassist from the Polyphonic Spree, although not a band I am into, I would encourage supporting him, and he is also very nice over email.

Why don't I just buy one? Well, I've been using my telephone capsule since before he came out with the copperphone and I'd just like to update it a bit. and I'm addicted to DIY projects.

thanks all!

PRR · May 6, 2005

The microphone in all classic telephones is Carbon. It is a Classic Sound, though note that VERY early in radio, they switched from that type mike to the Double Button Carbon mike for lower distortion. Carbon mike needs significant power, more than Phantom, and the product you point to clearly does not need power.

The classic earpiece in telephones is reversable, will work as a mike. It is 50-100 ohms, so there is no need for transformer or DI. Screw the black and white wires inside a mike cable to the two screws on the back. If it picks up buzz, clamp the mike-wire shield to the case of the earpiece/mike. The plastic cup over the earpiece on the telephone handset is part of the acoustic tuning; without that it will be more mellow.

rascalseven · May 7, 2005

I own a Copperphone from Placid Audio. Yes, I agree, it's a bit much for a one trick pony, however I can honestly say I'm finding lots of uses for it. The sound itself is much cooler than any filter-type or distortion-type plug-in I've used... it's dynamic.

I generally use it alongside another mic on most sources and find that blending the two signals makes for some really cool effects. Specifically, I've lately been feeding reverb/delay/whatever parallel effects from the copperphone track (pre-fader) to layer with the 'normal' dry track. This makes for some extremelly cool and original results. (I particularly like using it for feeding reverb from a drumkit or feeding delay from a vocal). The combination of filtered effect with normal track is awesome.

I just thought buying it was worthwhile since I'm spending so much time on building other stuff. Also, Mark is a cool guy (the guy who makes it), and I like to support cool and creative people.

Whether you buy it or DIY, the thing is cool. I highly recommend!

JC