Flash bulb power section

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TUBEDUDE
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Re: Flash bulb power section

Post by TUBEDUDE »

i guess the idea is like a compander with the input signal dynamics generating a control voltage that controls a VCA at the end of the preamp stages. meanwhile the signal passes through the distortion generating stages and then when they pass through the VCA the dynamics are restored to the distorted signal before hitting the PI/PA stage.

sounds easy in concept, but i'll bet it will be a bitch to sound natural.
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Colossal
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Re: Flash bulb power section

Post by Colossal »

EtherealWidow wrote:Thank you. To my untrained eye, those schematics look suspiciously boring... :?
You are suspiciously right. Boring. A C-R-C power supply is dynamic by its nature. It reacts and sags and the load line is a distribution, not a single point on the line, except at zero signal condition (when there is no sound).

Yawn...
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Leo_Gnardo
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Re: Flash bulb power section

Post by Leo_Gnardo »

Colossal wrote:
EtherealWidow wrote:Thank you. To my untrained eye, those schematics look suspiciously boring... :?
You are suspiciously right. Boring. A C-R-C power supply is dynamic by its nature. It reacts and sags and the load line is a distribution, not a single point on the line, except at zero signal condition (when there is no sound).
There are a couple surprises in the power surprise. Yes the output tubes are powered AFTER a resistor, isn't that also the plan in Vox AC30. So some sag there. Why all those series resistors in the next filter section? Bizarre. Regardless, screen grids are run at a voltage well below plates. No problem there, should help keep the EL84's from running away. And what's with the cathodes on the output drive tube. Brought to the negative (bias) supply instead of ground -"long-tail pair" I think it's called - I've seen this rarely in some hi fi amps but not guitar amps. So the 20/20 is a little different but not too weird. I still don't see any flashbulb caps, dual level class H supply or whatevers supposed to be exciting about this.
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Colossal
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Re: Flash bulb power section

Post by Colossal »

Leo_Gnardo wrote:There are a couple surprises in the power surprise. ...Why all those series resistors in the next filter section? Bizarre.
Do you see anything that warrants a patent? Looks like evolution, not revolution. Perhaps the series resistors are for some chokey inductance, either that or Mr. Smith really screwed up on his Mouser order and had a lot of 330R to get rid of.
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LeftyStrat
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Re: Flash bulb power section

Post by LeftyStrat »

Colossal wrote:either that or Mr. Smith really screwed up on his Mouser order and had a lot of 330R to get rid of.
LOL. I guess that needs to be added to the evil amp guru thread.
It's never too late to have a happy childhood.
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Reeltarded
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Re: Flash bulb power section

Post by Reeltarded »

TUBEDUDE wrote:
sounds easy in concept, but i'll bet it will be a bitch to sound natural.
No way! That is the easy part. Just snip all that crap out and make it not restore something that doesn't exist and never did!!
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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