Vactrols with a trick?

[DOX-EMF]

I just got some of this material http://www.rogerscorporation.com/durel/pdf/LIT-L9037 A01 short.pdf
Actually it's a pack of Cell phone screen backlights. Might be interesting.

An older Gates audio router had about a dozen little 9 pin tube based cans
containing 4 small cells and a 24 volt lamp for muting and switching. I plan to interface those cells since maybe they are already somewhat matched or at least broken in. McCurdy used the same type in some of their units in the late 60's. Fairchild had a similiar setup in the 6XX ?
discrete limiter with three cells as a pad in line with the audio.
The the audio was transformer coupled to a lamp drive circuit
for limiting. Can't get much more basic than that..... done with tubes it might have sounded good. An incandescent lamp output curve has some advantages. Good for Wein Bridge oscillators.

Bill

 

[Kit]

The T4B is a significant part in the LA2A sound because it has a "memory", and it change it's behaviour depending on how hard you hit it.

Yes, but that is not feature exclusive to the T4 module.
All Cds LDR´s will do this "memory" trick, more or less.

 

[rlaury]

The only problem with those EL panels is the life.
I would love to use them but I can't see using something
that could get totally dumb in 250 days (or say a year) of operation.
I know the duty cycle is not normally that high but it could be in a broadcast situation.

It just make sense to go with the LED OptoCoupler.


RonL