Rocket Mods

[JoshBernstein]

Hello all,
It's been a while since I built my rocket, and my tastes have changed a bit. I think im gravitating toward the fender sound, but i dont have the funds or time to build a new amp. The rocket is a little bright for my tastes now and the bass can be a lil loose. So i have a couple of questions.
1) What could I do to make the amp a bit darker, aside from the obvious bright cap reduction/removal?

2) Would there be any harm in introducing a switch to take the cathode follower/top boost section out of the signal path? That way I'd have that voxish normal channel and the bright, top boosted, rocket circuit available?

3) Is there anything i can do to make the amp accept a distortion pedal better? I undertsand that the rocket isn't really for this, but i want to get some more chunk out of my mesa throttle box.
Thanks,
-Josh

[xtian]

Sure, remove the bright cap. That, along with the existing Cut control, will make the amp as dark as you like.

To clean up the fat bottom, reduce the post-PI coupling caps to 0.02uF or 0.01uF.

[JoshBernstein]

Sure, remove the bright cap. That, along with the existing Cut control, will make the amp as dark as you like.

To clean up the fat bottom, reduce the post-PI coupling caps to 0.02uF or 0.01uF.

okay, will do. Thank you very much!

[RJ Guitars]

One of my favorite mods for a Rocket is to change the Tonestack to a Marshall style. This is very similar but adds a mid control. Then you can use the Duncanamps tonestack calculator to dial in the tone sweeps you want. (http://duncanamps.com/tsc/download.html). See this thread for the details of how I used this to dial in a bass amp: http://diyguitaramps.prophpbb.com/topic26.html

Ken Fischer designed the Rocket to have a heavy bottom but I have found that I just turn down the bass control to get what I want. By using the Marshall tonestack you can turn down the very low end and bring up the mids a bit... that sorta sounds like what you are asking for?

The Rocket is known for being one of the best amps on the market for running pedals. You could add an effects loop to it using any number of circuits. Again here is a link to one of Xtians threads on how to do that: http://diyguitaramps.prophpbb.com/topic74.html

If you want the ultimate amp for running pedals I like this one: https://tubeamparchive.com/viewtopic.php?t=26872

[M Fowler]

I changed one to Fender Twin Reverb tone stack with great success per the owner

[rooster]

A little late to this game but....

I was looking at the Rocket schematic that RJ drew? I do not use the 22uf cap on R5, but I recall a time when I said as much and a pileup ensued. I was under the impression that most here DID use this cap. Has this changed, have the Rocket ppl joined my team? And for the record, has anyone seen a real Rocket and saw the Kenny had a preference? I thought 2tone said the his stock Rocket had one in place?

Anyway, to the original poster, here's three things I would suggest:
#1) Remove the R5 cap if you have one in place.
#2) add a 220K resistor to ground and the junction of C8 and R10
#3) Maybe readjust your bias. If you have a 50 ohm bias resistor in place, change it to 65 ohms. Depending on the EL84s you are running you could be to far into the hot side of things.

And like RJ said, the Rocket circuit that I describe likes pedals just fine - and - as RJ says, turn the Bass control down. I run mine around 9 o'clock, FWIW. Good luck. Best OD for a Rocket IMO is the Timmy, make a note of this. The reason it is better than all the others is because you can control the amount of bass and treble of the OD [/*at the pedal].