What kind of noise? White noise? HUM?
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Iām surprised a 100k+ resistor would cause a significant drop in general volume if you still have the 9AB3 tank mentioned above which should have a 2575 ohm output impedance.
Oh well, it was worth a try.
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Definitely more of a hum.
Last question. New recent behavior? or it was always there?
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I feel like it is much worse after I rearranged things, though maybe I just didnāt notice it as much. I have the same modules on the power rail. While typing this response, I realized that it is a different power supply. Same type of power supply, just in a different case.
A couple of thoughts:
Tank Proximity to a power transformer matters - I often have issues with tanks in guitar amps
Is the tank grounded on both Input AND Output?
If so, does lifting ground on the tank output improve or exacerbate the issue?
This was a topic of discussion on an 60ās Ampeg Amp forum
I know you already replaced the cable so check that off the list
I have my Reverb Tank and module as far from the power supplies as possible in my case. I get the usual hissssss but no 60-120Hz hum
Ground Loops are Fun! EMI is too!
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Ok, I think I found the sources of the noise. Seems I canāt power any digital modules from the same wall wart as the reverb module, even though they are on a different rectifier/regulator circuit.
I was previously unplugging modules one at a time, and it made no difference. It only changes if I unplug them all.
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Underpowered? That can be an issue.
Too much ribble in the voltage will skewer the digital modules.
I have not measured the current draw on the reverb module yet. I think I might this week seeing as I need to follow through on a resistor value thing in mine.
Ill keep you in the loop
I am starting to put this one together. Did I see a chart somewhere that referenced what resistor values to use based on what tank you have or did I imagine that?
I got a 4EB2C1B 600 - 2250 Ohm - that I hopefully have not banged up too much!
What are the best suggested tanks for said Spring Spring Crunchy Spring Spring ?
So far my module seems to be working as expected, but whenever I turn the tone knob I start to get feedback (starting at like an 1/8th turn). Iām assuming thatās what the adjustable resistor is for? Whenever I turn it around it doesnāt seem to mess with anything, but Iāll be messing around with it some more today to make sure I have everything in itās proper place
This is a shot in the dark (dork?) as Iāve not built this one yet, I had to heavily adjust the the trimmers on the Twin T module to get rid of the decay feedback. Maybe thatās the issue here? Just a thought ā¦
Iāll definitely try it out, thanks!
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the components marked as 200 or ??? what is the rule of thumb on these??
Well itās built and essentially works, but thereās a lot of BUZZ on the wet. The RCA sockets may be the culprit as I read that they may be an issue, mine have the signal on the outer pins and the shield on the inner pin ( which I have had to bend into position) Thougts?
Rob
Mine is very sensitive to power supply noise. I have had to isolate it on its own power to get it to be noise free. I think springs are just susceptible to this kind of issue as my dreadbox hypnosis has the same issue.
Between the springs and the twin t drum PSU issues, I am getting some isolated power supply circuits together using the meanwell black box switching regulators that can be powered with some laptop PSUs to see if that will solve the problem. I donāt know how sensitive these are to switching regulator noise. It is a problem with the usb regulator that came with the hypnosis. I hope the expensive meanwells have better built-in filtering.
This is the paragraph I read on the project
"Please note! there are two types of the phono sockets and only one is correct. if you use the wrong ones its not thre end of the world you will just hear humm in the reverb as the signal is inverted. this is the type that is correct RVFM Red PCB Skeleton Phono Socket | Rapid Online . you will notice it has 3 grounding legs, then 1 leg at the back of it that is the signal. i know there are other types as i had this problem when i realised the one i used had the signal leg to the front of it. "
My RCAās were defo the wrong type so I have ordered some new ones.
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Ok, new RCAās no noise 
But all the WET seems to be just internal oscillation, bears no resemblance to the input. ? Is this controlled by the Trimmer on the back or is something else awry?
Thanks
Rob
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The trim pot adjusts the feedback level. I suppose you could just have that set too high and you are getting too much feedback, but I doubt that is the issue if you have the feedback pot turned down.