Headset output w/ UB802 Mixer

[siriusfox]

I've had a problem with my Mixer and headset combo.

I got my UB802 mixer a while ago and have had no problems with it. The mixer works great. I had one old microphone, that I was given from my grandfather because he couldn't get it to work. The only problem is it was me and a cohost, so we would need two microphones. The old microphone works fine.

I went out and bought a Sennheiser PC130 headset. http://www.amazon.com/gp/product/B0000AZJVP/sr=8-1/qid=1155179175/ref=pd_bbs_1/002-8537712-5448828?ie=UTF8. The problem was this mixer produced no output through the mixer. We sent it back as a defective headset about a week ago. My cohost bought a Logitech headset. He has sense called me on skype, and Gizmoproject and has been sure that it works just fine. http://www.amazon.com/gp/product/B0007N33IQ/sr=8-2/qid=1155178413/ref=pd_bbs_2/002-8537712-5448828?ie=UTF8.

Today he brought over the headset, and we found that it had the same reaction with the mixer. We have no idea what the issue is. All I have is the specs from Amazon, and the specs for the working microphone. If anyone can give me any info on what I need to do/buy to make this work, it would be greatly appreciated.

Working Mic -
Impedance 600Ω (Ohms for people who can't see that)
Sensitivity -75dB; 0DB = 1V/µbar, 1kHz. (µ is micro I think)
Input Sound: 130dB SPL with "AA" cell

Headset (Sennheiser) -
Impedance: 32 ohms
Characteristic SPL: 112 dB SPL at 1 V / 1 kHz
Frequency response (microphone): 80 Hz-15 kHz
Sensitivity: 38 dB at 1 V/Pa, 1 kHz

Headset (Logitech) -
Microphone sensitivity: 59 dBV/Bar, -39 dBV/Pa +/-4 dB

[WildeGeek]

The specifications for these headsets don't say whether they require the 3V bias voltage to power an amplifier for their internal electret condenser mic. They don't say at all what the microphone technology is. (I hate manufacturers who keep important specifications a secret.)

Chances are, the microphone input on the sound card of the PC your co-host used for Skype does provide this voltage; but your mixer definitely does not.

I don't know of any off-the-shelf solutions to fix this -- but I wouldn't be surprised if they exist. You'd either need a battery box to power the microphone, or a preamp that supplies the power and delivers line-level to your mixer.

(If I wanted to spend the time, I could probably design an adaptor that took the mixer's phantom power, and divided it down to power your mic.)

If it were me, I'd buy a headset, or just a different mic, that has an XLR connector and works with your mixer.

[BrianGentry]

Sounds to me like you are attempting to use electrolet microphones with a mixer. Electrolet mics are what you normally find in a consumer headset mic at your local stores. These types of mics need a few Volts of "bias" to make them work; usually 2 to 5 Volts. PC sound cards with mic inputs have that bias Voltage available all the time.

Mixers have no such bias Voltage. They have something called Phantom Power, but it is 48 Volts DC, and is designed to run condensor microphones (which are something entirely different). Phantom power can destroy electrolet microphones, so you don't want to try that.

Unfortunately, the answers aren't all that nice:

1. Get normal dynamic microphones, or condensor mics for use with your mixer.
2. Buy (or build) battery boxes that will provide the bias Voltage needed by your electrolet mics. These boxes will have one jack for the mic and second jack to feed your mixer.

Brian.