Half Power Rocket, Ampeg-style reverb, and an SMPS

Express, Liverpool, Rocket, Dirty Little Monster, etc.

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LeftyStrat
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Half Power Rocket, Ampeg-style reverb, and an SMPS

Post by LeftyStrat »

I'm starting a build of a half power Rocket using the power supply discussed in this thread:

https://tubeamparchive.com/viewtopic.php?t=17514


I have a Deluxe Reverb 8k output transformer. I'm also going to skip the choke and use a resistor in its place.

I also plan to add an Ampeg-style reverb, using a 6sn7 as the transformer-less driver, using the left-over 12ax7 triode as the recovery.

For those who have done half-power Rockets, did you drop the filtering? Considering the low impedance of this power supply, I'm thinking about lowered filtering and maybe a 300-500 ohm resistor to simulate the rectifier.

Any tips or suggestions appreciated.
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M Fowler
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Re: Half Power Rocket, Ampeg-style reverb, and an SMPS

Post by M Fowler »

I used dartanion's 1/2 power Rocket tranny set in my build.

I used a 2k2/3w sag resistor between main filter cap and B+2.
The layout doesn't show that however.

Mark
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Cliff Schecht
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Re: Half Power Rocket, Ampeg-style reverb, and an SMPS

Post by Cliff Schecht »

My lower power Rocket (quad of 6AQ5's) was a fun little amp but also had a weird resonance on the B string that I could never track down. Turned that amp into a rockin' sounding 5F6A and sold my Rocket to a buddy so now I'm down to just an Express.. Might have to fix that soon. :?
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diagrammatiks
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Re: Half Power Rocket, Ampeg-style reverb, and an SMPS

Post by diagrammatiks »

keep in mind that the high voltage line from that transformer is regulated.

you're not going to able to mimic rectifier sag.
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LeftyStrat
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Re: Half Power Rocket, Ampeg-style reverb, and an SMPS

Post by LeftyStrat »

I'm not all that concerned about rectifier sag. But shouldn't I be able to use a big resistor between B+1 and B+2 to get some compression from the screens?
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M Fowler
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Re: Half Power Rocket, Ampeg-style reverb, and an SMPS

Post by M Fowler »

It will reduce the voltage to the screens which could be a good thing.

Mark
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