When is a Hi-Z microphone desireable?

[DokorderFreq]

If you typically want to go up in impedance along the signal chain from source to output, outside of physical Z 'balancing' or 'matching', why would you want to plug a Hi-Z mic into, say a Hi-Z input of a guitar amp, PA or recording preamp/interface? Given proper XLR>TR(S) connections, why not just maximize the output benefits of Lo-Z mics at the getgo and use them exclusively? Is it increased noise per length of cable issues (dim light gaining intensity as I type)?

[ubertar]

Plug a low Z mic into a guitar amp, test it out, then swap in a high Z mic and you'll hear immediately why you'd want to do that. Higher output, better tone. It's not that often, at least in my experience, that you'd want to plug a mic into a guitar amp anyway, but a high Z mic is definitely more suitable for that application. Try it, compare it, and you'll hear for yourself.

[Scodiddly]

Neither is an ideal - it's a matter of matching input with output. Hi-Z into Hi-Z, Low-Z into Low-Z.

Low impedance mics get the ability to run longer cables without treble loss and/or interference, but back in the old tube days required spending money on a mixer input transformer. Semiconductors can deal with the low impedances directly.

[DokorderFreq]

Ahhh, OK. I was thinking the opposite in terms of cable losses, and I had the belief that Low-Z mics generally produced a cleaner signal. Understand that current technologies have this all sussed out, but we all loves our vintage gear, right. Best to fully know how to maximize what the old school kits can offer. Thanks, Guys!!

[lancebug]

I have an old Shure hi-z mic that I keep around just for running into ad-hoc PA's and such. Its great for "band practice" situations where you just want to quickly plug in to whatever's available to use. Its got its own funky lo-fi vibe as well. I think it might be a 585. It actually gets plugged in pretty often. I think I could probably run it direct into guitar pedals, which is something I have done before with other hi-z mics.

[Jim Williams]

The only current use for one is a ham radio set or maybe a Green Bullet Shure into a guitar amp for a blues harp.

Even that is best done low impedance. High impedance mic outputs create microphonic cables you can hear, especially with a bit of overdrive.

I wired the Green Bullet low impedance and use a Shure 200~50k ohm in-line step up transformer, plenty of high impedance output from that for a guitar amp. Mic is quiet, blues is heard.

[ubertar]

Yeah, that's the best of both worlds, what Jim's doing: low Z through the cable, then a step up transformer to high Z at the end. Les Paul wanted to switch the electric guitar industry over to low Z pickups, but it didn't catch on for whatever reason. At any rate, there are enough other ways to have low-noise pickups that it's not necessary, and I've never heard a high Z mic that was anywhere as noisy as a single coil guitar pickup.

[Jim Williams]

I recall Les Paul's low impedance push in the mid 1970's. He used/played that low impedance Les Paul model made back then. I had them around Rex Bogue's guitar shop back then. The output was rather low even using the high impedance outputs (there was a step up transformer inside the guitar).

I believe the reason they didn't catch on was this was an era when everyone except Les wanted higher output guitars to drive tube amps. The other reason was those low impedance pickups had no resonant peak in the audio range, it was ultrasonic and not heard. Every guitar player chooses his tone with that resonant peak giving guitar pickups their personality.

I have seen some guys play the Les Paul low impedance bass lately. Those types of sounds are better for bass than guitar.

[DokorderFreq]

The Les Paul Recording. Quite the bomb far as Gibson sales were concerned. Bad timing for ol' Les I guess. . . or just limited applications for the beast (high fidelity recording). Bass in a DI situation would benefit, and what with today's plug in simulators why not guitars too? Never live....no no no!