New Rocket has been launched...

[rbryerton]

Here's some pics of my Rocket clone I just finished. Relaxing build, nice & simple, and whoa, what tones from this thing!

Much more than what I was expecting: some very nice cleans, and a completely awesome early AC/DC type overdrive at noon on the gain.

As usual, TAG comes though: scored a used set of trannys nice & cheap, and the chassis, faceplate & case came from RJ...

I gotta say, this thing really surprised me in a good way Anyone want to buy a Vox AC30CCH?

Here's some pics:

[IMG:960:1280]http://www.bryerton.com/misc/twr-build/IMG_2382.JPG[/img]


[IMG960]http://www.bryerton.com/misc/twr-build/IMG_2387.JPG[/img]


[IMG960]http://www.bryerton.com/misc/twr-build/IMG_2391.JPG[/img]


[IMG960]http://www.bryerton.com/misc/twr-build/IMG_2396.JPG[/img]


[IMG960]http://www.bryerton.com/misc/twr-build/IMG_2399.JPG[/img]


[IMG960]http://www.bryerton.com/misc/twr-build/IMG_2400.JPG[/img]


[IMG960]http://www.bryerton.com/misc/twr-build/IMG_2402.JPG[/img]


[IMG960]http://www.bryerton.com/misc/twr-build/IMG_2403.JPG[/img]


[IMG960]http://www.bryerton.com/misc/twr-build/IMG_2405.JPG[/img]

After building a Liverpool & a rocket, I realized something: I need an Express now!!!

[UR12]

Lookin good!! Congrats on a cool build

[fishy]

Hard to argue with this amp and it never fails to impress those who try it.
I really like those faceplates with the train Rocket on them. Seem really apt.
That was the first commercial train which ran between Manchester and Liverpool. If we consider it as the first express train, then it covers the three main TWs...Rocket, Liverpool, Express

Congrats on the build.......

[RJ Guitars]

Rob,

You are a great craftsman... nice work!

I'm still amazed how many folks have built Rocket amps and you just don't hear too much about a bad sounding one.

Somebody posted up a Ken Fischer note once where he actually says the Trainwreck Rocket name was based upon Stephenson's Rocket, the first "modern" locomotive.

Great work on another amp build - seems like you are kinda like an amp building machine - I just barely shipped out that chassis to you and here you are Rocking and Rolling.

nice,

rj

[M Fowler]

Its great to see yet another Rocket my favorite, great works looks very good.

[Structo]

Man, you guys are killing me.

I want to build one of those so bad!

Oh well, I going to have to look around the old studio (spare bedroom) and see what I can sell to build me a Rocket!

[RJ Guitars]

4500, congrats Tom!

How bad to you want that Rocket build?

Maybe a birthright?

Surely not a soul?

Perhaps your firstborn?

Send me a PM and let me know what you have to barter... we do have a very special program for the badly addicted and desperate.

rj

[rawnster]

Man, you guys are killing me.

I want to build one of those so bad!

Oh well, I going to have to look around the old studio (spare bedroom) and see what I can sell to build me a Rocket!

Hey Tom, you should drive over and play my rocket sometime. You'll certainly get bit by the rocket bug.

Hi rbryerton, very nice build. Congrats!

[mclmk8d]

Nice job on the build...
One thing I've noticed about my Rocket versus the others is that Paul Ruby did not use a choke on mine, just the OT , PT, and what looks like a fat capacitor, all black; my uninformed guess is that replaced the choke. It has 2 speaker outputs and there is also a half-power: full-power switch in the back...do other Rockets have that?
[img:720:540]http://img64.imageshack.us/img64/712/img1461u.jpg[/img]

[dartanion]

I have used a few different chokes and a few different large resistors and I find that a nice wirewound 1K makes a nice replacement for the choke. Less money, no real huge tonal difference, and saves a bit of cash

[RJ Guitars]

When I first got interested in the Rocket amp I read Paul Ruby's posts. When he built that amp and he stated it pretty strong that the choke didn't do anything special and cost a lot of money.

I always figured Ken Fischer used a tube rectifier and a choke because he was sticking close to the AC-30 specifications. I think he liked the AC-30, just not the annoying parts of that amp.

Don't suppose you have some sound clips from Diana?

thanks,

rj

[rbryerton]

Thanks for all of the kind words and comments, guys; I appreciate it.

Generally speaking, how does a choke versus a wire-wound resistor change the sound or feel of an amp? Is it a sag thing? Or does the choke filter the supply better?

[M Fowler]

The choke (inductor) improves filtering and can be replaced with a resistor.

[FYL]

Generally speaking, how does a choke versus a wire-wound resistor change the sound or feel of an amp? Is it a sag thing? Or does the choke filter the supply better?

A choke is reactive, it shows little DC resistance - around 100R for a typical 4 H/80 mA model - and relatively high AC impedance - app. 3K @ 120 Hz for the same model.

Voltage drop is 8 volts @ 80 mA, 3 volts or so in real world conditions with only 30 mA or so thru the choke (amp maxed). Nearly no sag and excellent filtering.

Using a 3K resistor would drop 240 volts @ 80 mA and 90 volts @ 30 mA. That's a lot of sag and wasted B+...

Taking the TW Express, Ken F. used a 1K resistor, which dropped 30 volts @ 30 mA (amp maxed) and 15 volts @ 15 mA (close to idle). Very little sag and a good compromise.
Using a choke would have led to better filtering, less power wasted and a tighter amp overall.

Would it have been a Good Thing™? The jury is still out there: a properly voiced Express sounds on the bright side but well-balanced in stock form, using a choke changes her character quite significantly, adding a zingy edge, an overall glare, which IMO implies a re-voicing, particularly if you use EL34's and play a Strat or similar. Then the amp isn't an Express clone anymore...