JJ Dirt - Hum issues

[bryantabuteau]

Hey figured since there's a bit of activity in this group right now maybe someone can give me some tips. Getting a fair bit of hum on my JJ Dirt compared to my other high gain pre-amps (SL+, Recto, Mark X) and was wondering if it's just the nature of the circuit or if I could improve it/fix it somehow.

It starts getting a bit silly with gain at 12 O'clock, and putting a gate in front helps for any pickup oriented stuff, the hum is loud enough in comparison to the actual signal that a gate in the loop doesn't really do much.

I've swapped in and out a few different tubes types/brands to no real difference.

Thoughts? anyone else with this module and getting the same thing or different?

Sounds fantastic when I'm playing though, awesome sounding module.

 

[Capt_Tippy]

Hi bryantabuteau,

I just recently picked up a JJ. I don't remember that it's excessively noisy compared to my other modules. I can tell you that in general a lot of Anthony's Modules have more noise in them than I expected. It took some getting used to for me.

I don't own an SL+ or a Recto. I'm guessing that's a JF Mark X? It's hard for me to make a direct comparison for you because of that.

I can tell you that when I got my MashAll+ (for example) I was shocked at the amount of noise it has. I've learned to dial back the gain until its only the amount of gain I need. I don't just crank the knob to the right for the sake of cranking it to the right. I have found my gain knobs to be in many cases much lower than 12 O'clock. I also use a noise gate, and find its pretty much a necessity.

IMO its worth the trade for the tone you get out of a Salvation Module. There's a lot of tone is those noisy areas. I actually prefer equipment that you can make sound bad. (...and I'm not going to get side tracked going into all that)

Maybe if you made a clip it would be helpful in helping you sort it out.

...but you said "hum" do you have a grounding issue?

Probably should have posted this in the modules area though. Its possible some people might not look in this thread because of where you posted it.

 

[CrazyNutz]

Short of turning the gain down, probably not much you can do.

Have you tried a low noise tube in V1 of your amp chassis?

Does the board have goop all over it? If not, you can take a picture and I could probably determine whats causing it.

Hey figured since there's a bit of activity in this group right now maybe someone can give me some tips. Getting a fair bit of hum on my JJ Dirt compared to my other high gain pre-amps (SL+, Recto, Mark X) and was wondering if it's just the nature of the circuit or if I could improve it/fix it somehow.

It starts getting a bit silly with gain at 12 O'clock, and putting a gate in front helps for any pickup oriented stuff, the hum is loud enough in comparison to the actual signal that a gate in the loop doesn't really do much.

I've swapped in and out a few different tubes types/brands to no real difference.

Thoughts? anyone else with this module and getting the same thing or different?

Sounds fantastic when I'm playing though, awesome sounding module.

 

[bryantabuteau]

Maybe if you made a clip it would be helpful in helping you sort it out.

...but you said "hum" do you have a grounding issue?

Yeah, I might make up a clip. In terms of a grounding issue, not in my external signal path or in the power, not ruling out a problem with the module though. It's more 'noise' than hum really.

I've got a low noise tube in V1, and the board is pretty gooped, yeah.
I'll have a bit more of a fiddle round, see if I can pin it down.

 

[Capt_Tippy]

Ok well let me stress that my MashAll+ was sooo noisy sounding to me, I was emailing the dude I bought it from and saying... Hey!! This thing is effing broken!! LoL

I have like 17 modules ATM. Every single Salvation Module I own Id call on the noisy side. Stock Modules the quietest. Salvation the noisiest. ...but tonewise I doubt there will ever be many of my Salvation Modules for sale.

Just make a clip of the noise. Don't even need to play really. Ill hook my JJ up at some point and compare it.

 

[bryantabuteau]

Just make a clip of the noise. Don't even need to play really. Ill hook my JJ up at some point and compare it.

Cheers, will do. If it's just what they do, then all cool, I'll try and tame it with some gates.

 

[Mattfig]

I'm going with the Capt on this one....Gain-based modules, by their very nature, are noisey....Get a good gate like a Decimator G Series and you'll never notice it again...

 

[CrunchBunch]

High gain modules typically require reasonable amounts of inter-stage attenuation in the form of coupling resistors. These resistors produce a lot of the top end white noise that you hear with the gain cranked. I always use metal film 1w (sometimes 2w if space permits) resistors in these positions. The higher rating (although not required for power handling) results in a much quieter high gain module. Small anemic carbon based resistors should never be used in these positions.

I suppose with all of the black crap most modders put on its going to be impossible to tell what resistors were used.

 

[Capt_Tippy]

I suppose with all of the black crap most modders put on its going to be impossible to tell what resistors were used.

Anthony would probably tell you if you asked him. Just don't be a dick about it and say something stupid or insult him That guy is one cool individual.

I just popped open my JJ. There are resistors of all dif sizes on there so I'd say there's some 1/4, 1/2 and def some 1w as well. Possibly even bigger.

 

[Capt_Tippy]

Sorry to double post, but it's been too long to edit the last one.

Turned on the amp for a sec and checked it out.

bryantabuteau, You have the JBE switch down? (I'm guessing)

Mine gets a little hummy/noisy in that position. Output/SoundLevel is dropped a bit, but all the background junk is still the same volume in that mode.

You just gotta spend some time getting to know these modules. This **** isn't plug and play LoL

 

[bryantabuteau]

bryantabuteau, You have the JBE switch down? (I'm guessing)
Mine gets a little hummy/noisy in that position. Output/SoundLevel is dropped a bit, but all the background junk is still the same volume in that mode.
You just gotta spend some time getting to know these modules. This s*&t isn't plug and play LoL

Yeah, I was using it with JBE, and it's interesting that the output drops but the noise stays the same. I've had a big fiddle with everything today, trying some lower gain and moving my gate into different positions and I think I have it tamed to a point where it's not bothering me any more. It really is a great sounding module though.

Thanks for all the suggestions, I'll probably look at mapping out the circuit and replacing some resistors at some point in the future, but for now I'm pretty happy with it.