Optical cables

[puretube]

ooops, Jimbo: actually I wanted to save the 5k-post for the "Mojo-thread"...   

on-topic: I was stunned, when I discovered those optical PUs in Frankfurt a few months ago!

they were mainly demonstrating bass with them.

Terriffic!

they had a kind of "bass-karaoke" going on:
playback (trebly) of P*lice-songs
while the guy was playing bass...

they also used it as a hex-trigger for a guitar-synth: Fantastic!!!


a very underrated company.

this oughta change...

[Ardric]

I thought the point of implementing analogue optical signal carrying was to remain as much of the signal as possible and not worry about conventional cable shortcomings, such as resistance and capacitance.

Or have you pondered to other fields while I wasn't paying attention?

Oh probably!

A 500K impedence, mV level audio signal on a long coax cord snaked across a noisy enviornment?  With a shield dumped into it?  Seems to me that there's a million things that could be done to improve on this situation without having to give up copper for glass.  But like fiber optics, it might not plug into anyone else's stuff.

1/4" stereo TRS jacks do though.  T/R = transformer secondary, S = guitar shielding.  Drive the tranny with an onboard buffer.  If you use a TRS cable, you get a lowish impedence isolated balanced twisted pair for audio.  The guitar shielding has it's own path down the cable shield.  If you plug in a standard 1/4" mono cable into the guitar, the sleeve connects to ring on the plug, connecting the guitar shield in the traditional way.  It's not isolated any more, but you still get better drive into the cable thanks to the buffer.  You could add a ground lift switch or use a TRS cable with the sleeve disconnected at the instrument end for those times when you want the shield to float.  The preamp end could supply phantom power for the guitar, or power a FET-buffer-in-plug cable for standard instruments.  Or the TRS cable could end in an XLR for going direct.  Or end in a mono 1/4" plug for inputs other than our preamp... the shield then ties at that point.

This would seem to meet the requirements for better audio quality on a long cable run, is much simpler and cheaper to implement, and could possibly be compatible with normal instruments and inputs.  In my opinion it's the optical cable that should be equated with "the grass is always greener in the next field over".