Is your JD-10 noisy?

[fivenote]

I read a lot of good things about the Award Session JD-10. I was looking for a pre-amp/amp emulator to go straight to a PA boad. I recently was able to get a NOS JD-10. It's the model that was sold under the Morely brand. It's in new condition and works great, but...

I get a lot of white noise even at low-mid gain settings. There's even audible radio broadcasts at times. I get the same problem plugging into numerous amps, mixing boards, etc... so I've ruled out other equipment.

Anybody else experienced this? Do I just need to buy a noise gate pedal?

[trag-o-caster]

Generally no, but I do occasionally get radio signals. I found that by putting my old Rat pedal in front of the JD10, and turning it on, but keeping the distortion down low, and using the guitar's volume pot to clean up, would totally get rid of the radio interference, although I don't like playing with the Rat on full time.

It sounds to me like there may be something wrong with yours. I'd have it looked at. Mine will get the occasional noise, but not as bad as what you describe. Nothing that I couldn't live with.

[Jason S]

I have never tried to use mine live. But, I've never had excessive noise from mine during recordings.

[RomanS]

Never tried to use mine as a preamp for recording, but used as a stomp box OD in front of an amp mine is really quiet (I have the current version).

[Steven]

Never had any problems with noise from my unit during sessions or live.

[kludge]

Mine has noise problems too, both recording and live. It may be some sort of gainstaging issue, but I don't know exactly what.

It's a shame, because it sounds amazing.

[klasher]

Originally Posted by kludge

Mine has noise problems too, both recording and live. It may be some sort of gainstaging issue, but I don't know exactly what.

It's a shame, because it sounds amazing.

What do you mean by gainstaging? You mean running other overdrives/distortion boxes into it? Or do you mean something internal in the pedal itself?

[fivenote]

I got an MXR smartgate and put it after the JD10. It quiets the noise when the gate is closed, but as soon as I start playing, the gate opens and I hear the noise in the background.

Like kludge said "it's a shame" since it makes great tone. I am curious about what "gainstaging" is and if there's a way to mod or shield the box somehow to fix it. It alsmost seems to me like my input cable is acting as an antenna to the JD10. If I move or touch the cable, the noise changes, but it also changes if I touch the JD10 housing.

I bought it after hearing mostly good reviews, some eveing it was very low noise. Since then, I've read about a few who say it's noisy. I wrote to Morely and Award about it. Award deferred saying my model is a Morely product. Morely hasn't responded yet.

[garytelecastor]

I have had mine since the late 90's and I have had no problems with it whatsoever. The pots get scratchy now and then but a little cleaner and voila. I place mine as the first pedal in my chain now. Used to be last. I find that if I place it before my comp it really makes a difference in tone. But then again, I use amps so I guess my input is pretty much not worth the time to read, but it's way too late for that now isn't it?

[kludge]

Originally Posted by klasher

What do you mean by gainstaging? You mean running other overdrives/distortion boxes into it? Or do you mean something internal in the pedal itself?

I'm talking mostly about recording... it may need a direct box after it to match the signal to the line input for my recording device better. I also have the Behringer speaker emulator/direct box, and thought IT was noisy, until I got its levels matched right with my recording device. Now it's totally quiet. I just haven't tried working the JD10 that way yet. I hope I can get it straightened out, because I LOVE the JD10's tone. It does that "OOOooo..." thing on long note decay SO well, like a really good tube amp.

[fivenote]

I discovered that if I place one or two smaller pedals side-by-side on top of the JD-10, the radio interference goes away. I'm low on electrical knowledge, but I'd guess all the metal of the other pedals is shielding the JD-10.

Does that make sense to any electrical engineers out there? If so, would it make sense to shield the inside of the JD-10's metal box with copper foil tape much like what you'd do with a guitar's control cavity?

[fivenote]

Originally Posted by fivenote

would it make sense to shield the inside of the JD-10's metal box with copper foil tape much like what you'd do with a guitar's control cavity?

I'll guess that since the box is already a conductive metal, then it should already be shielded. I'm thinking that maybe the ground from the input jack is not connecting to the metal enclosure.

[kludge]

Originally Posted by fivenote

I'll guess that since the box is already a conductive metal, then it should already be shielded. I'm thinking that maybe the ground from the input jack is not connecting to the metal enclosure.

That's an interesting thought. Maybe I should pop mine apart and check its case grounding. Yeah, the noise I've heard isn't hum, and probably isn't white noise either... it's either RF interference, or a noisy component inside the box.

[fivenote]

I opened up the JD-10 last night and found where the RFI noise was coming from. It wasn't the input our ouput jacks not being grounded or bringing in RFI.

Instead, it was the wires that run from the footswitch to the printed circuit board. They are the only wires in the whole unit. Everything else is mounted on the pcb. I took a .001uf cap and touched it across a couple of the leads on the footswitch and it immediately bled off the RFI. The box got very quiet w/o any change to the tone when playing the guitar.

The footswitch has six leads, five having unshielded single conductor wires connected to it that run to the pcb. I'm not sure exactly what goes to where, so I didn't make a permanent mod. I need to get my multimeter and try to figure out how the switch is working and make a best guess where to solder on a permanent cap or resistor to bleed off the RFI. So far the best results came from putting the cap across the middle two leads.

I'll post more when I figure it out. Meantime, if anybody else knows more on how the switch is working in the JD-10, please post. I suspect my JD-10 is not broken, but that I'm using it in a dense RF area (New York City) and these unshielded switch wires are susceptible to picking up RFI that gets amplified by the preamp.

[kludge]

Originally Posted by fivenote

I opened up the JD-10 last night and found where the RFI noise was coming from. It wasn't the input our ouput jacks not being grounded or bringing in RFI.

Instead, it was the wires that run from the footswitch to the printed circuit board. They are the only wires in the whole unit. Everything else is mounted on the pcb. I took a .001uf cap and touched it across a couple of the leads on the footswitch and it immediately bled off the RFI. The box got very quiet w/o any change to the tone when playing the guitar.

The footswitch has six leads, five having unshielded single conductor wires connected to it that run to the pcb. I'm not sure exactly what goes to where, so I didn't make a permanent mod. I need to get my multimeter and try to figure out how the switch is working and make a best guess where to solder on a permanent cap or resistor to bleed off the RFI. So far the best results came from putting the cap across the middle two leads.

I'll post more when I figure it out. Meantime, if anybody else knows more on how the switch is working in the JD-10, please post. I suspect my JD-10 is not broken, but that I'm using it in a dense RF area (New York City) and these unshielded switch wires are susceptible to picking up RFI that gets amplified by the preamp.

Oooh, thanks for the research! I popped the top off of mine last night, just to see if a: it would change the noise figure, and b: if it might be a bad battery. No to both. I'll try the cap thing myself... if I could make the JD10 quiet, it'd be back on my board in a flash!

[trag-o-caster]

Originally Posted by fivenote

I opened up the JD-10 last night and found where the RFI noise was coming from. It wasn't the input our ouput jacks not being grounded or bringing in RFI.

Instead, it was the wires that run from the footswitch to the printed circuit board. They are the only wires in the whole unit. Everything else is mounted on the pcb. I took a .001uf cap and touched it across a couple of the leads on the footswitch and it immediately bled off the RFI. The box got very quiet w/o any change to the tone when playing the guitar.

The footswitch has six leads, five having unshielded single conductor wires connected to it that run to the pcb. I'm not sure exactly what goes to where, so I didn't make a permanent mod. I need to get my multimeter and try to figure out how the switch is working and make a best guess where to solder on a permanent cap or resistor to bleed off the RFI. So far the best results came from putting the cap across the middle two leads.

I'll post more when I figure it out. Meantime, if anybody else knows more on how the switch is working in the JD-10, please post. I suspect my JD-10 is not broken, but that I'm using it in a dense RF area (New York City) and these unshielded switch wires are susceptible to picking up RFI that gets amplified by the preamp.

Thanks so much for posting your research and the results! I'd never heard of anyone trying to deal with the RF issue. As I said above - anytime that I was getting radios coming through the amp, I'd just kick on the Rat pedal and turn it's distortion down, and the radios would go away. It doesn't happen very often though. It seemed to happen a lot more with a compressor in front of it.

I wish someone would make a bullet-proof, problem free version of the JD-10. I'd be the first customer!

[fivenote]

I made the mod to the JD-10 and the RFI is gone!!! I found some info on how to add capacitors to amps and guitars to block RFI, such as http://www.muzique.com/lab/hum.htm. As I posted earlier, I found the RFI was not coming from the input or output jacks. Touching a cap across those spots didn't make a difference. Then I tried the footswitch and it's lead wires. Bingo!

I first figured out a little about the switch. The top poles of the DPDT switch (toward back of unit) are running about 5v. The bottom poles (toward front) go to ground. The middle pair of tabs are the common ones. Putting the cap there bleeds the RFI whether the switch is on or off. I soldered a 220pf cap from the 5v side to the ground side. I was able to place it across the surface of the switch and solder it in without having to resolder the wire leads.





It was an easy mod. Once done the JD-10 was very quiet - except for my guitar signal of course. I'm on the 24th floor of a NY city high-rise. With a few more dental fillings, I could probably get radio in my teeth here :-). But my JD-10 is quiet. Even the rock channel is free of RFI and has just the normal high-gain hiss that my noise gate handles without problem. I love the JD-10's tone and am glad it's now RFI-free!

If you're up to a little risk, try the mod. If mine decides to crap out after a while because of the mod I'll be sure to post to save others from the same fate. But I jammed on it all evening, trying all settings, and it's working great. As far as I can tell, the mod didn't affect the tone or output levels.

I hope this helps others having the same problem.

[RomanS]

Very cool, thanks! Unfortunately, there's not "Helpful post of the week"-award here, otherwise I'd nominate you!

[fivenote]

Originally Posted by RomanS

Very cool, thanks! Unfortunately, there's not "Helpful post of the week"-award here, otherwise I'd nominate you!

Thanks RomanS. Your posts about how much you like the JD-10 helped steer me towards getting one in the first place.

[kludge]

Thanks, fivenote! Pictures and everything! Maybe with a little luck, I'll have time to do that tonight; otherwise it gets done saturday.

I'd suspected RF noise because I noticed it was the same whether on or off... that was the noise that drove it off my pedalboard. Wish I'd had the good sense to go looking for a place to bleed off the RF, like you did!

[fivenote]

Originally Posted by kludge

Maybe with a little luck, I'll have time to do that tonight; otherwise it gets done saturday.

Let me know how it goes. I asked Award-Session for a limited schematic of the JD-10 to show how the switch is wired, but haven't gotten a response yet. If a few of us have success with the mod, I may forward a link to this thread to them. Maybe they could confirm if this mod is a good thing or use it as feedback to improve their current model somehow.

[Fender56]

Originally Posted by fivenote

Let me know how it goes. I asked Award-Session for a limited schematic of the JD-10 to show how the switch is wired, but haven't gotten a response yet. If a few of us have success with the mod, I may forward a link to this thread to them. Maybe they could confirm if this mod is a good thing or use it as feedback to improve their current model somehow.

You can have access to the schematics here:

http://www.diystompboxes.com/smfforu...?topic=18372.0