Twin Reverb Reissue to ODS Conversion?

[Chris Brown]

Hi all... I lurk here but never post... until now...

I have a 65 reissue Twin Reverb and it's a great amp and everything... I've gigged with it for years... I'd like to convert it to an ODS... maybe...

The cleans are great of course but I'm so burnt out on trying to get a nice saturated tube overdrive out of stompboxes... I've cloned every popular distortion and overdrive but nothing sounds like preamp tubes breaking up... you know.

Anyway...

I was going to sell it to fund a ceriatone ots100 kit but the more I researched it I realized that it might be feasible to strip out the twin's pcb and do a conversion.

The twin's tolex is beat up pretty bad so it's not likely that I could get top dollar for it anyway.

What is the general consensus? Pros and cons... please load me down with info.

[wicker]

Why touch such a nice amp ? Reissiue is all pcb, you need to do new turret/elelet, probably new faceplate, few hours of soldering, I suggest just making ODS, rather than coverting Twin - few hours of fun more, but some extra cash for iron and chassis. You can always do only OD amp, will be a little cheaper, and easier, that's what I would do.

[FUCHSAUDIO]

The chassis is large, the transformers tolerable, and why give your money to anyone overseas making a paper thin chassis with unknown transformers in it. You'll enjoy making something yourself that you can be proud of, customize it to your need and wants, and it can be made to sound terrific.

It's a mass-produced PCB amp in stock form, with no particularly hot resale value anyway.

Plenty of tubes for a loop, adding a reverb, a fancier driver circuit. Make up a nice faceplate and be proud !

[gary sanders]

Yes I have a perfectly working Carvin X100B head I am about to murder to make a better amp.Its full of opamps and switching transistors.It deserves to die.

Post your progress!

[FUCHSAUDIO]

I did a few of those Carvins....decent iron, they end up pretty nice.

[FUCHSAUDIO]

If you plan out the panel properly, you have plenty of room for everything with little to know drilling, and it can look terrific !! This is a RI Super, with an ODS conversion.

[ic-racer]

This could be a formidable task if this is your first tube amp build. However, here is a thread with a layout and schematic that may get you started.

https://tubeamparchive.com/viewtopic.php?t=2976&start=0

I did a Super Twin Reverb conversion that I love, but I did not replace the circuit boards (thats a point to point amp) so it may not me of much help in your situation: https://tubeamparchive.com/viewtopic.ph ... sc&start=0

[talbany]

Here is a Twin conversion HRM style w/Loop .. Should be to scale..Print cut drill..If you take it on..

Good Luck!

Tony

[Chris Brown]

Thank you all for the feedback and the great info.

I am definitely going to do this. This will be my first tube amp build... I've done cap jobs and mods as well as basic troubleshooting and biasing but I've never started with a blank board. I'm really looking forward to the experience.

Aside from amps I've been building stompboxes for a little over 5 years and I'm hoping a lot of those skills will transfer over... I've never worked with turret board... it looks more workable than the pad per hole perfboard that I'm used to building fx circuits on.

I haven't settled on a schematic yet... seems like 124 is a popular starting point for a lot of builds. Any thoughts on this? Am I overlooking any pitfalls?

Would the extra preamp tube socket from the twin most wisely used for the fx loop or for a 1 tube type reverb circuit? Any thoughts on that?

I want to get a good plan in place before I start mousering parts so any input is invaluable.

Thanks everyone

[FUCHSAUDIO]

You should have enough sockets for a full on ODS, plus loop and reverb. Weber makes plug covers if you have unused holes too.

[Chris Brown]

Wow there are so many options. I have a lot of questions... I really appreciate all of this helpful feedback.

So yeah why not go with the standard reverb design huh... i was thinking simplicity but I'm a lover of the twin's reverb so why not take advantage of it.

I suppose the extra chassis real estate and sockets would best be used like this... stage 1&2, OD 1&2, Loop, Rev send, Rev recovery, PI ... am I overlooking anything? Is there a more awesome way to utilize the sockets and space?

I plan to leave out the fet input... will I miss it if I do?

What's the consensus on the hrm stack after the od stage? From the sound clips I've sampled it seems like the standard non-hrm builds sound more foucsed and a little bit more compressed... less open... I really like that. At the same time it's very tempting to go for the hrm... I play stratocasters so the ability to dial in the od tone might be a big plus. Is that tightness really lost with the hrm stack or is it something that just has to be dialed in?

Should I just stick close to #124 + reverb/loop for now and save the hrm stack for a future build?

Thank you all again for helping me plan this project. I look forward to your thoughts.

[Bob-I]

Wow there are so many options. I have a lot of questions... I really appreciate all of this helpful feedback.

So yeah why not go with the standard reverb design huh... i was thinking simplicity but I'm a lover of the twin's reverb so why not take advantage of it.

I've done that, but I've found that the reverb is simply too intense for my use. The one tube reverb many folks here have used fits this amp better. JMO

I suppose the extra chassis real estate and sockets would best be used like this... stage 1&2, OD 1&2, Loop, Rev send, Rev recovery, PI ... am I overlooking anything? Is there a more awesome way to utilize the sockets and space?

I'd skip the 2 tube reverb and just leave one tube unused.

I plan to leave out the fet input... will I miss it if I do?

Nope, not unless you use very low output PUs like Lindley does on his lapsteels.

What's the consensus on the hrm stack after the od stage? From the sound clips I've sampled it seems like the standard non-hrm builds sound more foucsed and a little bit more compressed... less open... I really like that. At the same time it's very tempting to go for the hrm... I play stratocasters so the ability to dial in the od tone might be a big plus. Is that tightness really lost with the hrm stack or is it something that just has to be dialed in?

There's actually more differences in the HRM amp than just the post OD stack. OD entrance, bypass caps, etc. I agree with your assessment of the differences but I prefer the gentler HRM tone.

Should I just stick close to #124 + reverb/loop for now and save the hrm stack for a future build?

It's a good idea to stick with known good sounding values so the 124 is a great starting place. Add the Dumbleator loop and one tube reverb and you'll have a great amp. If you're not completely happy, it's easily modified to HRM or BluesMaster specs.

Good luck with the project.

[tubedogsmith]

For a strat I'd put together a high plate classic style amp, non HRM and go ahead and ad reverb and the loop. HRM amps can sound great with strats too but for a new builder than can take a lot of work to optimize.

[Tonegeek]

I am just finished with a similar converion (https://tubeamparchive.com/viewtopic.php?t=12541). There are others here who have done similar conversions and as Andy said, there is good iron and lots of room in the Twin and not much drilling involved (I did not drill a single hole on the front panel and only 2 on the back panel). If it makes sense economically, go for it. I am losing money on mine in a way, but this amp sounds fantastic with my Strat or Hamer so i am happy. I would do a low plate non-HRM if you want the clean sound to be closest to the Fender clean sound (I did and it is). The HRM amps do require a longer tweak time IMO. On the non-HRM amps I agree with most that the .047 mid cap sounds best for Strats but I like the .01 mid cap on the HRM amps. Buy one of each and season to taste or put on a switch. Probably TMI at this point so I will end here. Just ask if you have questions.

[Structo]

I agree, put the mid caps on a switch. .01uF and .05uF

Also, putting a switch on the local feedback loop on V1b is nice as well.
That is a pretty subtle effect unless you have it turned up quite loud.

Another neat tweak which I haven't tried yet is to put the global neg feedback (presence circuit) on a switch.
I believe Henry does this on his presence pot. Turn the pot all the way down and switch it off.

I also really like to have a relay that turns on the bright cap on the volume pot when in clean mode only, then when you switch to OD it goes off.
Keeps the clean nice and sparkly.
Scott turned me on to that idea and Tony drew the layout for it.

The down position is off, middle is on all the time and up is bright when in clean channel.
You need a On-Off-On switch and a relay.