Rocket Group Build project

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

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ODwan
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Re: Rocket Group Build project

Post by ODwan »

My Express build is definately louder than my Liverpool. Don't get me wrong, the 'pool is still very loud. Actually and sadly too loud to play with my band in our practice booth so I have to use an atenuator.
Timo
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UR12
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Re: Rocket Group Build project

Post by UR12 »

ODwan wrote:My Express build is definately louder than my Liverpool. Don't get me wrong, the 'pool is still very loud. Actually and sadly too loud to play with my band in our practice booth so I have to use an atenuator.
Timo
I agree. The Express is 5 to 10 watts louder that the Liverpool. But like you say the Liverpool is still loud and so is the Rocket. Have you tried 6V6s in your Express? The Liverpool, and the Rocket too, are both Cathode biased and as such lend themselves very well to power scaling.
ODwan
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Location: Germany, near Hannover

Re: Rocket Group Build project

Post by ODwan »

Dana,
I plan to power scale my Liverpool someday, but suitable pots are hard to get here in Germany. I know Ican order trough Digikey, but they have a €100,- minimum order. So I wait till I have enough to order. Money is an issue, too these days :(
I've tried it with some zeners on the CT but the amp lost his feel completely. I guess you just have to scale the powertubes and install a limit control.
And yes, I have tried 6V6s in the Express but I just like EL34 better.
Timo
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UR12
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Re: Rocket Group Build project

Post by UR12 »

Timo

I just use a standard cheap alpha 1/2 watt pot for the scaling control. It has a lot of voltage on it but very little current. I also like to scale the whole amp instead of just the power section. That way you don't need the extra drive control. If you can get your hands on an old blown up computer power supply you can usually find a big power mosfet in those that you can scavage for free. Total parts for doing a liverpool would be 1 pot, 2 resistors, a zener diode, and a mosfet. Should be less that $5us if you can get the mosfet for free. 8)
johnspeck
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Re: Rocket Group Build project

Post by johnspeck »

UR12 wrote:It is interesting to note that Paul didn't use the choke or tube recto and Diana turned out nice by all reports.
Diana has a tube rectifier.
ODwan
Posts: 170
Joined: Mon Jan 17, 2005 7:53 pm
Location: Germany, near Hannover

Re: Rocket Group Build project

Post by ODwan »

UR12 wrote:Timo

I just use a standard cheap alpha 1/2 watt pot for the scaling control. It has a lot of voltage on it but very little current. I also like to scale the whole amp instead of just the power section. That way you don't need the extra drive control. If you can get your hands on an old blown up computer power supply you can usually find a big power mosfet in those that you can scavage for free. Total parts for doing a liverpool would be 1 pot, 2 resistors, a zener diode, and a mosfet. Should be less that $5us if you can get the mosfet for free. 8)
Dana,
maybe I'll give the Alpha a try, though it is barely within it's rating. Have one 1Meg lin lying around together with a IRFP840. The other components are available at a local store. Also I have that Cut control on my 'pool which is easily converted to a limit control. ...and it's already tight in the chassis.
Timo
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UR12
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Re: Rocket Group Build project

Post by UR12 »

johnspeck wrote:
UR12 wrote:It is interesting to note that Paul didn't use the choke or tube recto and Diana turned out nice by all reports.
Diana has a tube rectifier.
John

I stand corrected. :oops: I was thinking he used SS diodes and 1k resistor in Diana. Am I wrong about the choke also?
johnspeck
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Re: Rocket Group Build project

Post by johnspeck »

Nope, you were right, no choke.
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UR12
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Re: Rocket Group Build project

Post by UR12 »

I finally got around to building a head cab for my new Rocket and thought I'd give you a look of it in it's new home. I took the non traditional approach and built a tolexed cab instead of the cherry.
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Buschman
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Re: Rocket Group Build project

Post by Buschman »

Is there a schematic for power scaling??
Thanks!
Chad
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Re: Rocket Group Build project

Post by Chad »

Thats a great lookin Rocket there Dana ! I like that look. Chad
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RJ Guitars
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Any Rocket Sound CLips?

Post by RJ Guitars »

I'm a bit curious of this project. I've got a chassis that seems to be right spec for a Rocket, Liverpool, or an Express and I'm just starting to get my layout marked out on it. I'm still deciding between the Liverpool and the Rocket and I won't drill any holes until I get that decided.

I'd be interested in some clips of a Rocket if anybody has them...

thanks,

rj
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