Overdrive reverb variants
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Overdrive reverb variants
Guys, mainly out of curiosity (and maybe for a future build) I'd like to discuss some ORDS derivatives. We all know about #13 and #60 and those are pretty well documented by now.
When working on my latest build, someone posted a gut shot of the Bloomfield Drive from Two Rock. I think this is an interesting amplifier for a couple of reasons. To me it looks like a typical low plate classic, but the reverb is different. Reverb drive is two stages, ala for example the Wonderland (just one triode is transformer loaded, 3k9 in the cathode). What surprised me is that the reverb driver is fed from the output of the clean gain pot, also like the wonderland. So that would be the usual case for a pre OD reverb like in #13, right? One more clue that it's a #13 in disguise: V1 is the clean preamp, V2 is the reverb driver, V3 is the mixing stages and V4 is the OD stage.
Anybody who knows if the reverb is actually pre OD like #13 and Two Rock skimped on the mixing stage?
When working on my latest build, someone posted a gut shot of the Bloomfield Drive from Two Rock. I think this is an interesting amplifier for a couple of reasons. To me it looks like a typical low plate classic, but the reverb is different. Reverb drive is two stages, ala for example the Wonderland (just one triode is transformer loaded, 3k9 in the cathode). What surprised me is that the reverb driver is fed from the output of the clean gain pot, also like the wonderland. So that would be the usual case for a pre OD reverb like in #13, right? One more clue that it's a #13 in disguise: V1 is the clean preamp, V2 is the reverb driver, V3 is the mixing stages and V4 is the OD stage.
Anybody who knows if the reverb is actually pre OD like #13 and Two Rock skimped on the mixing stage?
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Re: Overdrive reverb variants
Rootz,
I am definitely interested in this. The Bloomfield Drive sounds very good. I really like #102 but want to build at least a JM for cleans if not a full ODS reverb variant.
I am definitely interested in this. The Bloomfield Drive sounds very good. I really like #102 but want to build at least a JM for cleans if not a full ODS reverb variant.
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Re: Overdrive reverb variants
Take a look at this schematic. Essentially it's a Wonderland with added OD stage. To keep the tube count the same, I took the reverb entrance from the output of the relay and can thus ditch the triode in front of the reverb tank driver of the Wonderland. I kept one triode from a 12AT7 to drive the tank, the other triode is used as reverb recovery. The signals involved should be about equal to the Wonderland.
What I can't really account for is the difference in high end when comparing this design to the Wonderland. The first triode of the reverb circuit, the 12AX7 coming of the gain pot, loads the signal down a bit due to Miller capacitance I think. That effect is not present in the design below. No idea how it would sound. Pretty good I'd think, need to try it out soon.
What I can't really account for is the difference in high end when comparing this design to the Wonderland. The first triode of the reverb circuit, the 12AX7 coming of the gain pot, loads the signal down a bit due to Miller capacitance I think. That effect is not present in the design below. No idea how it would sound. Pretty good I'd think, need to try it out soon.
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Re: Overdrive reverb variants
InterestingThread. Just out of curiosity regarding the schmatic. I noticed that on the reverb driver tube the 10K grid stopper is insdte the LNFB. Any reason for that? I am asking beause I always had the suspicion SSS number 4 was wired the same
Re: Overdrive reverb variants
I couldn't notice much difference when simulating the position of the 10k resistor. The Wonderland hasn't got that feedback loop, the 004 does. However, I see both ways being done in the 004. Ceriatone, Two Rock (Sterling), Hartman place the 10k before the loop, but in the Dumbleland and 002 schematics and layouts I have the 10k is in the loop. FWIW, I could use one lug on the tag strip less when placing the 10k in the loop, you'd need two lugs the other way.
Maybe someone else will give more insights on this matter, it's an interesting question!
Maybe someone else will give more insights on this matter, it's an interesting question!
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Re: Overdrive reverb variants
Very interesting indeed. The Ceriatone actually does something weird, although the 10K is out of the loop they place the resistor on the plate and the capacitor after the 10K, which is the opposite of what one would expect.rootz wrote: ↑Fri Dec 06, 2019 12:34 pm I couldn't notice much difference when simulating the position of the 10k resistor. The Wonderland hasn't got that feedback loop, the 004 does. However, I see both ways being done in the 004. Ceriatone, Two Rock (Sterling), Hartman place the 10k before the loop, but in the Dumbleland and 002 schematics and layouts I have the 10k is in the loop. FWIW, I could use one lug on the tag strip less when placing the 10k in the loop, you'd need two lugs the other way.
Maybe someone else will give more insights on this matter, it's an interesting question!
As in Dumbleland, do you mean the Silver Alligator Amp (which technically is a SSS due to the style of PI)? Or is it another model?
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Re: Overdrive reverb variants
This is the possible Dumbleland schematic I mean.
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Re: Overdrive reverb variants
Just wondering if anyone has been inside a bloomfield Drive?
Any schematic info
Any schematic info
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Re: Overdrive reverb variants
I am not sure if this is helpful/useful to you, but the Brown Note Blue Monkey 44 I just finished has reverb. It's a bluesmaster/HRM.
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-Matt
It may very well be that the sole purpose of your life is only to serve as a warning to others.
It may very well be that the sole purpose of your life is only to serve as a warning to others.
Re: Overdrive reverb variants
Thanks for the layout.
I'll take a look, I played a Bloomfield a few weeks ago and really liked the amp.
I'll take a look, I played a Bloomfield a few weeks ago and really liked the amp.
Re: Overdrive reverb variants
What reverb pan and transformer did you use??professormudd wrote: ↑Fri Nov 27, 2020 6:05 pm I am not sure if this is helpful/useful to you, but the Brown Note Blue Monkey 44 I just finished has reverb. It's a bluesmaster/HRM.
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Re: Overdrive reverb variants
ClassicTone 40-18034 with a Belton 9AB2C1B tanksamrock55 wrote: ↑Wed Jan 06, 2021 10:48 amWhat reverb pan and transformer did you use??professormudd wrote: ↑Fri Nov 27, 2020 6:05 pm I am not sure if this is helpful/useful to you, but the Brown Note Blue Monkey 44 I just finished has reverb. It's a bluesmaster/HRM.
-Matt
It may very well be that the sole purpose of your life is only to serve as a warning to others.
It may very well be that the sole purpose of your life is only to serve as a warning to others.
Re: Overdrive reverb variants
Thank you