Who knows this piece of gear: Symmetra Peak SI-58-1A Limiter

Hi there,

I just bought this obscure piece of gear - another eBay auction I won "by accident" with a low ball bid.
All I know is that it was commonly used for AM processing, something that messes with the symmetry of signals.

Moons ago, I read rave reviews of a weird "passive limiter", sounding dope on kick et al.
Can't remember the name though, but now I hope this is the very unit the guy was raving about back then.
There can't be all too many passive limiters floating about, right?

Any insight?

Cheers.


Michael

I hope you didn't pay too much; that's not a limiter and there's a good chance that it won't be "dope" or even halfway useful in your studio.

It's a 4-pole passive all-pass filter with a phase shift that varies several hundred degrees across the audio band. It's intended to work as a sort of "phase rotator" (actually more of a "phase scrambler") in broadcast operations, to equalize the asymmetic peaks in speech waveforms. It would be great for ham radio, or other speech-only transmission chains.

But since you've bought it, try it out on different things. Who knows? It might make a cool effect for certain sounds.

Its actually pretty cool, but shhhh dont tell anyone.

dave

Thanks for the input.
In the mean time I read some posts of Mr. Orban (The broadcasting equipment guy): They're in deed all pass filters designed to balance out the positve and negative halfs of audio signals.

Funny thing is that I often wondered why vocal takes sometimes look pretty "uneven" in the wave editor. According to Mr. Orban, especially male voice generally has more energy on of the sides. Go figure.

Whatever.
I paid $ 160.00 for both - fair enough.

Dave, mind sharing what's so cool about these critters?

Cheers.


Michael

[quote author="mig27"]

Dave, mind sharing what's so cool about these critters?

[/quote]

did you plug it in?

dave

Nope - the pair still needs to travel over the pond (I'm located in Berlin).

ah, should be self evident when you plug them in. Put it in series with a limiter and see.

dave