plotting out deluxe rvb with some dumble bits

[imo1]

Hey yall!

I have a brand new project called the Texas Headhunters that is currently out doing a tour with Samantha Fish. Our record comes out in August and we will be touring extensively through the fall and spring.

I've been using a 50W amp that I built based off of the JM100. I ended up changing tonestack back closer to Fender, and changing a number of cathode caps, as well as a couple of coupling caps. It is great for the shows with my band where we are playing big clubs, theaters, and festivals.

With this lineup, there are 3 guitarists. This run we are playing PAC's and my amp would be way too loud. Its got me thinking about what I can build that would be road worthy, not too loud, and sound great. I also would like to be able to use chassis and cabs that are already built as the metal and woodwork i don't have tools for, time is limited, and would rather spend it on the circuit.

I am thinking of going with a mojotone deluxe reverb chassis and cab. Solid state rect. Similar filtering to the dumble type stuff. Don't need the "jazz" switch" but probably would use the PAB as one option, and would like to use channel 1 as an overdrive channel. I know it can get a bit tricky with the overdrive getting scratchy when used on a typical fender type tone stack, but that is pretty fundamental to my sound, and I'm hoping I can find something that works.

I probably will put a mid pot on, and probably gonna do the dwell thing on the reverb too, as it makes the reverb much more usable.

My biggest issues with Deluxes is the bass falling apart. I haven't ever built one with the solid state and additional rectification, but I'm thinking it might be good to go with a slightly beefier OT. Also thinking i would probably put the gain and pab on switches so would need a PT that would be capable to powering the relays as well.

I played a Dumble modded deluxe reverb a couple of years ago. It was pretty cool. A little different than what I'm looking for, but an amazing circuit.

I was wondering if anyone had built anything similar and if they had any thoughts on it. If anyone has layout ideas, that would be amazing too! I would love to avoid the doghouse if i can, but don't know if there is a way to get that all in the top chassis.

I appreciate any thoughts and ideas. I've learned a lot here and its been cool to be able to build amps that are really designed around my playing.

Ian

[dbharris]

Hi Ian,

If you search the Dumble discussion section for Hotel Hog and Ultraphonix you will find a lot of helpful information.

-Dan

[martin manning]

I am thinking of going with a mojotone deluxe reverb chassis and cab. Solid state rect. Similar filtering to the dumble type stuff. Don't need the "jazz" switch" but probably would use the PAB as one option, and would like to use channel 1 as an overdrive channel. I know it can get a bit tricky with the overdrive getting scratchy when used on a typical fender type tone stack, but that is pretty fundamental to my sound, and I'm hoping I can find something that works.

I probably will put a mid pot on, and probably gonna do the dwell thing on the reverb too, as it makes the reverb much more usable.

My biggest issues with Deluxes is the bass falling apart. I haven't ever built one with the solid state and additional rectification [filtering], but I'm thinking it might be good to go with a slightly beefier OT. Also thinking i would probably put the gain and pab on switches so would need a PT that would be capable to powering the relays as well.

I played a Dumble modded deluxe reverb a couple of years ago. It was pretty cool. A little different than what I'm looking for, but an amazing circuit.

This sounding like a 22W ODS Reverb. I agree for expediency and decent quality Mojo chassis and cab would do nicely. A Hammond hi-fi OT would be nice. You could also look into the Brown Note D-lite 22 for most of your schematic.

[imo1]

Hi Ian,

If you search the Dumble discussion section for Hotel Hog and Ultraphonix you will find a lot of helpful information.

-Dan

I’ve read a lot about ultraphonix in the past, though it was all done from curiosity, without a goal in hand. I don’t know “hotel hog” but will do some research. We are on tour with little computer time and it’s hard(at least for me) to get too deep on the iPhone.

Thanks for the suggestions!

[imo1]

Martin,

You may be right in terms of where to focus. I kind of got it in my head to use a deluxe chassis and cab, since they are so easy to find, but it does sound like some version of an ODS may be the path.
I built a couple of those and the cleans didn’t work for my style. It’s hard to explain in words, but I’m trying to hone in on what it is in fenders that does this thing I miss in the ODS.

I built a deluxe style amp for my kid and I used a raised board(I really don’t like the fender style boards). I’d rather not use the doghouse as those seem silly to me. I don’t like the way the routing works, and prefer the dumble style by the PT. I just don’t know if there would be enough room, and then I would be doing that struggle with the preamp tubes being out of line with their components, or design the whole board from scratch..

I know. Not trying to sound lazy. I’m just trying to be smart with the time

I’m trying to come up with something that isn’t gonna be an albatross as I am pretty busy this summer and would like to have it for our record release.

I do like that D’lite. I might poke around to see if monotone has an chassis cab.. I could just cut a couple of extra holes.

I would love to hear any thoughts on how a hi-fi OT amp might sound in that circuit. I know deluxe reverbs pretty well, and they really fall apart in the bass. I have tried different speakers, which makes a difference, but i guess I’m hoping I can get a little more round, solid low end, while still retaining that nice high bite that circuit can get

It’s all the little things like silk screening that drive me crazy. I often end up with unlabeled pots or some half assed attempt to use those pencil scratch letters or labeler.

[imo1]

Has anyone used a doghouse to house the bigger, Dumble style caps before? I'm a little concerned that it won't all fit in the top. Maybe i could put the main caps and then use one or 2 locally in the pre amp?

I've been looking at the designs again, and I am thinking of using the base Deluxe design with the vibrato channel kind of "as is" and then trying the OD gain on the normal channel.
I want to look into some of the ultraphonix mods, but will probably keep the fender tone stack. From what I remember people in general struggle with the gain side on the Fender style platform as it tended to be a bit scratchy.

On my JM style build, I found that using the lower cathode caps(4.7uF) on the early stages was nice, but I didn't like them across the board. It made the bass sound kind of pointy in a way that wasn't pleasing to me. That is a much higher wattage circuit, so I'm thinking I may try to start with the standard circuit there before I mess with the cathode caps

[martin manning]

You could use a stand-up power transformer and reclaim that space inside the chassis.
Are you planning to cascade the channels like an ODS? The OD channel needs the clean channel feeding it to do its thing.
Custom faceplates are not too hard to do. If you can draw it up and make a .pdf there are shops that can make you nice aluminum plates.

[imo1]

I'm thinking about that. I'm just not sure. I typically end up going to a single channel thing and then using pedals to do what i need, and that is pretty dialed in. I also like working and supporting the pedal companies I work with. I just feel like the normal channel is typically wasted in a fender. I do like the idea of having built in tremolo.

I think if I could somehow get a deluxe reverb to do all the good things it does without farting out in the bass, I would be really happy.

Has anyone had any success with doing kind of a standard fender main channel, and then trying the overdrive, as in the ODS circuit, over that? Seems like an obvious choice, and you could have it if you needed it, but wouldn't effect the main channel if you didn't dig it.

If I had more time, I would like to experiment with the ultraphonix mods. They are pretty different from a lot of the territory I've stayed in. I think for now, figuring out a good solid state rectifier situation with the big filtering will be my focus

[didit]

Hello Ian --

You've an interesting topic in play here. Given wise decision on silicon rectifier one can conveniently bolt a radial cap can in the reclaimed GZ34 space. Abundant dual section choices -- an example that aligns with beefing up for bass could be F&T's 500V 50/50uF. This handles both initial "plate" and "screen" nodes. With attention to layout there's room for all the rest of the power decoupling filters locally on your primary circuit board, particularly if you stay on single channel track. Up sizing the output transformer along with wise choice for your speaker is essential to bottoming out bass response. A hifi transformer might be an answer. I only rarely invoke Mercury Magnetics however they do produce a "fat stack" Deluxe Reverb that is attractive to do what I believe you are seeking; attractive except for their price tag. Would you consider blending Deluxe Reverb with Vibrolux? You might give the AA964 schematic a review as the starting point; with a beefed up Vibrolux output transformer (8 Ohm tap) pushed by a pair 5881 power tubes you get a '60s era Fender platform with confidence of the bass response. A modern Hammond Deluxe Reverb power transformer is sufficiently overspec'ed to handle the modest additional filament plate currents.

I'll leave discussion around folding in an ODS stage or some flavour of ultraphonix for later.

Best .. Ian

[didit]

Just to add another opinion: Fender style chassis and matched cabinet seems an easier platform though if major additional holes are needed aluminum is much much easier to machine.

Best ..

[martin manning]

...one can conveniently bolt a radial cap can in the reclaimed GZ34 space. Abundant dual section choices -- an example that aligns with beefing up for bass could be F&T's 500V 50/50uF. This handles both initial "plate" and "screen" nodes. With attention to layout there's room for all the rest of the power decoupling filters locally on your primary circuit board...

This is a great idea. Maybe go with the JJ 40-20-20-20. It's 1.5" diameter but the terminals might fit through the chassis hole. You could parallel the 40 and one 20, leaving a 20 for the screens, reverb driver and the LFO, and use the last 20 for the PI. That keeps the common ground forced by the can cap restricted to the power amp. DR only had one more filter, but it might not be a bad idea to use two, one for the input stage and one for the OD stage and the reverb recovery tube.

[didit]

This is a great idea. Maybe go with the JJ 40-20-20-20. It's 1.5" diameter but the terminals might fit through the chassis hole. You could parallel the 40 and one 20, leaving a 20 for the screens, reverb driver and the LFO, and the last 20 for the PI. That keeps the common ground forced by the can cap restricted to the power amp. DR only had one more filter, but it might not be a bad idea to use two, one for the input stage and one for the OD stage and the reverb recovery tube.

This definitely works. I've my own project that's highly aligned, however building it in a Princeton chassis. Hopefully our interminable renovations will pause long enough for me to unpack my amp workbench tools and put it together. Only to say I've been overthinking too much about how to do, versus just doing.

My only comments are that: it has less flexibility in tweaking the capacitance at each node to suit; and I can gratify my minor technical obsession about placing all bulk capacitance adjacent to its associated sub-circuit. That said, the 60uF + 20uF for the first two nodes is doubtless well suited to the original outlined goals.

Best ..

[lonote]

I have built a few combo amps using a Bassman chassis & it is probably my favorite size to use.

It is not as long as a Deluxe, but is longer than a Princeton & has the extra front-to-back depth that the big Fenders have. Gives you lots of space & options.


Pic below is a combo cab I built for an actual Bassman using Princeton proportions, sitting next to a Princeton for reference.

[imo1]

Hello Ian --

You've an interesting topic in play here. Given wise decision on silicon rectifier one can conveniently bolt a radial cap can in the reclaimed GZ34 space. Abundant dual section choices -- an example that aligns with beefing up for bass could be F&T's 500V 50/50uF. This handles both initial "plate" and "screen" nodes. With attention to layout there's room for all the rest of the power decoupling filters locally on your primary circuit board, particularly if you stay on single channel track. Up sizing the output transformer along with wise choice for your speaker is essential to bottoming out bass response. A hifi transformer might be an answer. I only rarely invoke Mercury Magnetics however they do produce a "fat stack" Deluxe Reverb that is attractive to do what I believe you are seeking; attractive except for their price tag. Would you consider blending Deluxe Reverb with Vibrolux? You might give the AA964 schematic a review as the starting point; with a beefed up Vibrolux output transformer (8 Ohm tap) pushed by a pair 5881 power tubes you get a '60s era Fender platform with confidence of the bass response. A modern Hammond Deluxe Reverb power transformer is sufficiently overspec'ed to handle the modest additional filament plate currents.

I'll leave discussion around folding in an ODS stage or some flavour of ultraphonix for later.

Best .. Ian

I love the vibrolux. In fact, I use mine often in a head form with an 8r 2x12 cab, and absolutely love it. The issue is that it will be too loud. On our last tour, one of the other guitar players used a Vibrolux and was playing it on 2, with it often being too loud!
It’s tricky, but I think staying in the deluxe realm volume wise, but cleaning up the low end a little bit, is the ticket for what I need to do.

[martin manning]

It’s tricky, but I think staying in the deluxe realm volume wise, but cleaning up the low end a little bit, is the ticket for what I need to do.

There are some standard tricks for this, i.e. decrease the size of the PI coupling caps, and/or increase the grid stoppers on the 6V6's. Have you tried any of that?