Cascade mod explained?

Double-Bubble! Place for discussing the 36W version...

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asd
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Cascade mod explained?

Post by asd »

I've been scouring the boards + net before posting, but haven't found my answer. I found an abundance of info on the 18 watt cascade mod, but not the 36 watter.

Would someone be so kind as to explain the cascade mod wiring for the 36 watter? I have read that you also may need to modify another cap value to avoid the "farting out" on bassy notes?

Ideally I'd like to wire it w/ a switch after I get it working.


Please forgive my newbness....

Thanks,

Scott
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rock_mumbles
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Post by rock_mumbles »

The 36 watt is just an 18 watt with four output tubes and larger transformers ... everything else is basically the same.

To start, just put the 18 watt cascaded preamp in front of the PI and 18 watt output section. Then tune to taste.
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Bronsboi
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Post by Bronsboi »

I'd start by using the split cathode values for the parallel channel before adding the switch etc for the cascade mode so you can get a feel for what it'll sound like...
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Post by asd »

Thanks guys.

Scott
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guitar-rocker
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Re: Cascade mod explained?

Post by guitar-rocker »

asd wrote:I've been scouring the boards + net before posting, but haven't found my answer. I found an abundance of info on the 18 watt cascade mod, but not the 36 watter.

Would someone be so kind as to explain the cascade mod wiring for the 36 watter? I have read that you also may need to modify another cap value to avoid the "farting out" on bassy notes?

Ideally I'd like to wire it w/ a switch after I get it working.


Please forgive my newbness....

Thanks,

Scott
I have found that a 1000uf 63V cathode cap on the power tube bias makes an audible difference. (which would be one per each set of power tubes on the 36W).
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Post by guitar-rocker »

Bronsboi wrote:I'd start by using the split cathode values for the parallel channel before adding the switch etc for the cascade mode so you can get a feel for what it'll sound like...

You could, but then you'd be missing the power of the plexi, and that truely would be a shame.
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Post by Bronsboi »

You'd be missing the power of the plexi
Very true guitar-rocker. (great clips BTW) However the parallel mod is very simple and for the newbies like me, a good place to start. I think it's a definite improvement over the standard lite 2b. Easy to reverse if you don't like it! All you need is the parts a soldering iron and 20 minutes!
Scott , give it a go!
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