ghost power and 1/4″ to 1/8″ to 1/4″

[David Watson]

Let me clarify: I meant when using adapters from one size to another, and you have to deal with stereo to mono it can be a problem.

For example, when working with all mono and going from 1/4″ to 1/8″ using an adapter, all you are doing is sending the same mono (1-ch) signal through a smaller cable diameter size, so the adapter just needs to act as a gateway from the larger diameter to the smaller one.

But when working with stereo to mono as well as diameter size, the adapter needs to mix the stereo (2-ch) signal to a mono (1-ch) signal. This is where it depends on the adapter. I’ve used adapters that only take one channel of the stereo signal and use it as the mono (usually the L channel), which can cause problems when you also need to worry about the R channel signal.

David H. Watson
dEhiN Entertainment

[Richard Crowley]

Yes, dealing with 2-pin vs. 3-pin connections is an issue in some cases. Please remember that 3-pin does not imply “stereo”. I believe it is misleading to refer to adapters and cables as “mono” or “stereo”.

In this specific case, the (still unidentified) receiver (presumably the power amplifier in this “system”) has only a 1/4 inch input and it seems quite safe to assume it is probably NOT a proper balanced (3-pin) input.

There are very few proper 3-terminal MIC inputs that use 1/4 inch connectors. For example the Tascam DR-680 which uses them for the 5th and 6th inputs for space reasons.

Likewise, the use of a single connector for stereo is typically the domain of headphones, earbuds, and low-end microphones with 3.5mm mini phone plugs (consumer camcorders, DSLRs, voice recorders, etc.)

[Peter Groom]

Agreed Richard
I always refer to 3 and 2 pole connections as balanced and unbalanced.

For my advice, dont use adaptors-ever. Get the right cable and always stay balanced.
Peter

Post Production Dubbing Mixer

[Ty Ford]

Hey Brian,

You can have phantom on with a professional dynamic mic. It won’t hurt anything, but won’t help.

You will have problems if you hook up an unbalanced (consumer) mic to a balanced input with phantom power (If you can actually figure out how to do that). And, you can sometimes damage a professional ribbon mic by connecting it to a mic pre with the phantom turned on.

Regards,

Ty

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[Richard Crowley]

Phantom power on an unbalanced (2-terminal) connection, (if one can even manage such an abortion) will FRY any dynamic or ribbon microphone. Dynamic mics rely on having BOTH of their signal leads connected to the 48V, for a net current of zero. But if you ground one side (as for unbalanced connection), the 48V passes right through the coil which is a VERY VERY BAD THING.