Rocket Done Tonight

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

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Ron Worley
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Re: Rocket Done Tonight

Post by Ron Worley »

RJ Guitars wrote:
Finally, what kind of caps are those on the right side of the picture? They obviously are not orange drops... kinda look like Xicon polyesters?

rj
Rj-

The caps are Panasonic's, I will be updating the BOM with the correct part number, etc and Digikey has them. I have been moving over the past 3 weeks into a new house.... the studio PC is not unpacked yet, which is where the amp stuff resides... perhaps this weekend....

Ron
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Lonely Raven
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Re: Rocket Done Tonight

Post by Lonely Raven »

Congrats on the house, Ron!!
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Lonely Raven
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Re: Rocket Done Tonight

Post by Lonely Raven »

Allynmey wrote:Castor, it's much different than the Express/Liverpool. I used a custom tranny that was made from KF's linecard. Essentially, a Dynaco A-470 tranny with a few changes. The amp is swirly and jangley. The Cut control is backwards in the Rocket also. This was confirmed with two real Rockets. It operates as a reverse "Cut" or "High Emphasis" knob. The best description I can give is with the Cut control all the way down, it is soft and bassy but clear. As you increase the "Cut" control, the amp adds highs but also dimension. With the Tele I was using, it was like having a six string ovation with the control off and full on was like a 12 string and the knob was a mix control. It got more "swirly and "3-D" as I increased the knob. Best way to explain it.
The cut on the Rocket I got from Carlos is very much like that. I turn it up (brighter) more and more. I don't like having it *less* then 1 o'clock.
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rfgordon
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Re: Rocket Done Tonight

Post by rfgordon »

So what PT did you use? For a B+ of 275 after a 5AR4 you're looking at, what, like a 220-0-220 at, say at around 175 mA?
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Allynmey
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Re: Rocket Done Tonight

Post by Allynmey »

The tranny puts out around 510VAC to the rectifier (255-0-255). The amp runs really hot (bias) with a 50 Ohm Cathode resistor :wink:
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Re: Rocket Done Tonight

Post by rfgordon »

Allyn,
OK, so you're using Ia to pull down the B+. I'm still curious about the PT you used. Who offers that voltage (255-0-255) with sufficient HT current for a 30 watt amp? I don't see that in CEDist's list of Hammonds, and most Fender-style iron has higher voltage. Is this one of Moose's offerings?
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Bear
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Re: Rocket Done Tonight

Post by Bear »

I've wanted a Rocket for a long time but this is really upping the lust. Is there a drool emoticon?

Bear
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Re: Rocket Done Tonight

Post by skyboltone »

Allynmey wrote:The tranny puts out around 510VAC to the rectifier (255-0-255). The amp runs really hot (bias) with a 50 Ohm Cathode resistor :wink:
I saw that and thought I was seeing things. Wow.
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Allynmey
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Re: Rocket Done Tonight

Post by Allynmey »

The trannys were from Heyboer. Customs from KF's line card. They were ordered by RHinson.
Zippy
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Re: Rocket Done Tonight

Post by Zippy »

Mark wrote:Ken Fischer couldn't have done better himself!
This does seem to have a few "improvements" on the classic Fischer style - a more robust chassis and the standoff mounted ground buss bar (as seen in the Fischer Memorial amp built and documented by the Amp Guild. Very nice.

I still haven't found those stand offs for the ground buss - at least not in the Mouser catalog. Ron, are you going to include those in the BOM? (Update: FOUND ' em in the BOM. Thanks, Ron.)
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RJ Guitars
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Re: Rocket Done Tonight

Post by RJ Guitars »

Zippy wrote:... This does seem to have a few "improvements" on the classic Fischer style - a more robust chassis and the standoff mounted ground buss bar (as seen in the Fischer Memorial amp built and documented by the Amp Guild. Very nice...
What is the impact of the chassis and other subtle differences on the final amp... do you need ultra thin aluminum and sheet metal screws to get "the tone". From another recent thread https://tubeamparchive.com/viewtopic.php?t=5718 Geetarpicker had an interesting comment on the original Bud Box Chassis.

So I am pondering the thought that it is likely a loose boundary on a slippery slope (also read that as "an opinion") that delineates the clones from the hybrids? Is it fair to think that every amp that KF did not build himself is really a hybrid?

Man we really need those elusive sound clips from the "Real Rocket"... would they tell us we have truly cloned the Rocket?

rj
geetarpicker wrote:BUD AC-425 off the shelf box. No longer in production, but maybe can be obtained by special order in quantity? The bottom plates are still available. I built both of my personal use clones on these, and found another one recently on ebay for $20 to save for a rainy day. For the most part they are made of "unobtainium" @ .050 thick, and are really hard to find anymore. Folks will dis the fragile nature of these, but my original is totally fine after 19 years. Also folks WILL fight me on this FOR SURE, but I think these make a difference in the tone and feel of the amp. Maybe a happy accident as Ken probably used them because they were cheap and easy to obtain at the time.

Let the battle begin... 8)

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drhulsey
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Re: Rocket Done Tonight

Post by drhulsey »

Zippy wrote: ... I still haven't found those stand offs for the ground buss - at least not in the Mouser catalog...
Ampwares was the only source I found (along with the obligatory long delivery time). Ron Worley had another source, IIRC.
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Ron Worley
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Re: Rocket Done Tonight

Post by Ron Worley »

I found the type I was selling from a guy in Oregon- I bought all he had, and sold all that I could. I kept some for my own builds in the future, but not that many.

Dr. Tim, I think that an enterprising group like this would go in on a bulk custom order for a bunch....... :wink:

Ron
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skyboltone
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Re: Rocket Done Tonight

Post by skyboltone »

Ron Worley wrote:Dr. Tim, I think that an enterprising group like this would go in on a bulk custom order for a bunch....... :wink:

Ron
We need a master tool maker to noodle a rotary stamping tool that will churn them out by the turn of a crank from ordinary rolled strip copper. Otherwise we have to find who has the tooling already. Clarostat in Mexico may have it. Probably 10,000 piece minimum.
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Re: Rocket Done Tonight

Post by Mark »

Dear Allyn

Could you take a few more photo's of your Rocket clone?

I'd like to see the earth etc in more detail. Oh yeah, what does the amp sound like when it is moving some air?
Yours Sincerely

Mark Abbott
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