TW Express vs 18-watt clone

[xtian]

Starting to get the itch to build a new head. I like single channel models and no reverb for simplicity. This time I want more clean headroom, but a switchable extra gain stage is always cool. And VVR or other good master volume scheme for bedroom practice.

Can someone distill the differences between the Trainwreck Express and 18watt clone builds? Seems like each can be tweaked for more or less gain, TMB tone stacks. The 18watt's usually have a tube rectifier, which would be a novelty for me. And they use 84s instead of the Express' 34s.

FYI, I play both single coil and humbuckers, and I have a Mesa Boogie MkIV head, so an amp that's different than the MkIV is better.

So: What's the diff?

[selloutrr]

can I make a suggestion? lets take both and combine them.

TW circuit
Tube Rectifier
EL84s

TRAINWRECK ROCKET!

you could half power it and remove two of the el84 output tubes when you don't want that much power. Adjust for the ohm load.

[M Fowler]

https://tubeamparchive.com/files/wreckxpr.pdf

Here are your builder's pissing around with different variations of a TW including a pair of EL84's.

Mark

[Richie]

Might also look into the T-rex. Which has an 18 channel,and a Wrectified channel the 2 melded together. Mark Huss has some of the info on his site,and has a switcher for the channels. You could do it EL84 or 6v6s or whatever with a few value changes.
Some clips may be out there too of the amp. A few have built it.
mhuss.com. Oh wait, i forgot, they say people here can't design anything of thier own..

[Darkbluemurder]

can I make a suggestion? lets take both and combine them.

TW circuit
Tube Rectifier
EL84s

TRAINWRECK ROCKET!

you could half power it and remove two of the el84 output tubes when you don't want that much power. Adjust for the ohm load.

I second that suggestion.

Since the Rocket circuit uses only 1 1/2 tubes you have one half tube left for your extra gain stage. You could put that either in front of the amp (like a Marshall 2203 with High and Low Inputs) or make it switchable. In the latter case you may want additional controls to adjust gain and level of the gained up sound.

Cheers Stephan

[dartanion]

I second Richie's suggestion of Mark Huss' Trex! Best of both worlds with that circuit. Wreck on one channel, 18 watt on the other. Add Dana's VVR and away you go.

http://mhuss.com/18watt/schematics/18wTRex.pdf

[PCollen]

Starting to get the itch to build a new head. I like single channel models and no reverb for simplicity. This time I want more clean headroom, but a switchable extra gain stage is always cool. And VVR or other good master volume scheme for bedroom practice.

Can someone distill the differences between the Trainwreck Express and 18watt clone builds? Seems like each can be tweaked for more or less gain, TMB tone stacks. The 18watt's usually have a tube rectifier, which would be a novelty for me. And they use 84s instead of the Express' 34s.

FYI, I play both single coil and humbuckers, and I have a Mesa Boogie MkIV head, so an amp that's different than the MkIV is better.

So: What's the diff?

Consider the 18-watt TMB version. One clean channel and one higher gain channel that is configured like a Marshall Plexi lead channel. And you can get more headroom by out of the PI by changing the PI tail resistor to 47 or 33K. You can switch between the two using a A/B box.