NAD! JVM Content... JVM Guys I have some questions for you!

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PhloridaMan

PhloridaMan

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So I finally got my amp! It was as described from Ricky Rockhardo on here.

The overall tone of the amp is great but there are some things I am having some major issues with...

The biggest issue is noise... The ones I played at GC were nowhere near this obnoxious! The highs are extremely piercing if I turn them anywhere higher than 7 o clock on OD1 and OD2 and when I turn the channel and master volumes to about 1 o clock each, the amp really loses it's tone and sounds extremely "hard" is the only way I can describe it... There is also a TON of feedback and not much low end... I am wondering if it needs tubes? What do the JVM guys suggest for tubes in these? I know when I talked to him about the amp he said he had not changed the tubes. The amp is a 2008 according to the barcode on the back, I am wondering if the tubes have NEVER been changed at all?


The second issue... Using my MAXON OD808... I have ALWAYS run gain settings on amps quite low, 10 o clock or so and boosted with my OD808... On my Framus, I would set the Gain to 0, Tone to Noon and Balance maxed... I never had any issue on the Framus, but I tried those identical settings last night on the Marshall and HOLY $#IT! The thing sounded like I was choking a turkey!!! Feedback, Squealing all kinds of crap... It was not good... I had to back the "balance" knob all the way down to 10 o clock, at which point it was completely useless to have cause it did nothing...


The third issue... My Ground Control Pro/GCX... It just wont communicate at all with the amp... Mine is an old Digital Music Corp (pre-Voodoo Labs) Version, but they are just pretty much the same thing... The Framus took it and it was an 09, so there should be no reason the Marshall wouldn't work... I searched out this "tutorial video" where supposedly all you have to do is touch the footswitch/program button twice till it flashes once you have all your settings the way you want them... Click the channel button on the Ground Control Pro, and youre done... It doesnt do that... It doesnt do ANYTHING! :doh: :doh: :doh: https://www.youtube.com/watch?v=2B7f6iYBulw

That's it for now... I am happy with the amp, I know from the ones I played in GC, the tone is what I am looking for I guess I just need to get these 3 issues figured out and go from there!
 
Nice great amp! I love mine.

I would definitely replace tubes if the are the original ones from 2008. I lurk Svetlana Winged C's for power and I currently use EH 12ax7s throughout mine.

With regards to high end problems I don't have that and find the EQ to be very responsive. Certainly no lack of low end.

Feedback is a natural thing when volumes are set high. But could perhaps be a bad pre amp tube...

As fr the switch. I thought I was only the Marshall switch you could programme or you ha to go the midi route?

You press the "footswitch programme" button on the amp once till the indicator light comes one, select you channel, mode, master, etc.... Then hold down which ever switch you want to use on the JVM footswitch till all the indicators lights flash. Done.

Not sure about other floor controllers.


But for your main problems I would definitely get new tubes first.
 
Well with the footswitch, it's clear in that video I linked in my OP that the GCP is capable of switching the JVM... I spent 3 hours messing with it last night and came up with nothing. Tried all different configurations on the pedals settings and nothing. I just don't get it. I will be beyond mad if I can't use it for some dumb reason. That's the only reason I bought a JVM instead of a Quick Rod or DSL... My whole rig revolves around that one pedal being able to be used.
 
Phil Jacques":2it2nm6c said:
Well with the footswitch, it's clear in that video I linked in my OP that the GCP is capable of switching the JVM... I spent 3 hours messing with it last night and came up with nothing. Tried all different configurations on the pedals settings and nothing. I just don't get it. I will be beyond mad if I can't use it for some dumb reason. That's the only reason I bought a JVM instead of a Quick Rod or DSL... My whole rig revolves around that one pedal being able to be used.
Click to expand...

Oh! My bad, looking on my phone. Didn't see the vid, sorry!

When I programme my footswitch I only pressed the footswitch button on the faceplate once. Then set channels, master, reverb, modes then once happy with that you hold down which ever button you want to assign that to.

Is that what you are doing?
 
Never had a JVM But once I removed the EH tubes and put JJ'S in my DSL it opened it up and pulled out some fizz on the top end.

Replace your tubes and keep them as spares.
 
Another thing I noticed last night when turning it on was all the tubes were pretty bright, glowing much brighter than my Framus or Peavey use to... Another thing making me think bad tubes.
 
Just talked to Voodoo lab, Gonna play around with the GCP tonight... Guy on the phone seems to think it may be as simple as being set to the wrong midi channel or a bad midi cable (which I didn't even think of cause the cables were brand new when I assembled the framus rig and have not moved in a year)

Tubes are ordered and on the way... Looking at the Comp mod also.
 
There are tons of mods flying around and people going crazy on the soldering iron with their JVMs but having no clue what they do. Let's hope yours is still stock and just some toob issues.
 
Hm. Wow...all my trebles are set at 11 o'clock except for the clean channel - it's on noon. And it's not piercing at all - sounds about right. And i get a little bit of feedback on the OD channels, but not really much actually. Sounds like you may have a bad tube or tubes? Hopefully that's all it is lol. I like the stock tubes in it too lol. Mine are all branded "marshall" so i'm guessing they're stock...
Also mine has plenty of low end. With the bass set to noon or just barely over noon on every channel. Sounds.like something's wrong with yours.
 
As others have said...sounds like it could possibly be your tubes. That would be the easiest fix and the one I'd hope for. If you have some spare 12AX7's around...trying switching them out and see if that helps. If it's still running the original tubes that's a lot of wear depending on use plus shipping and things like that. Again, as others have said...no problems with mine...really easy to dial the amp in.

I generally run 9th gen 12AX7's in mine and Ruby EL34BSTR's. I've had KT77's, Mullards and the SED's in mine and prefer the Ruby EL34BSTR's...not to mention they won't break your wallet.
 
Had 2 JVM205H's. YES, they are noisy. Noisiest amp I've ever owned. ISP Decimator, that cut it more than in half. Couldn't live without with either one. Without it, I wouldn't be able to stand the white noise/hiss.

I recommend JJ KT77's, and a mix of pre's. My best luck was the KT77's, Tungsol in V1, JJ ECC83S in V2 & 3, C9 in V4, and a balanced JJECC83S in the PI. JJ's are not for everyone, obviously, but the KT77's sounded better - warmer, and tighter than the SED's I had in both. Svetlana EL34's sound good too. For a New Sensor/Sovtek-made tube, they are warmer than the SED's as well. GREAT tube.
The ECC83S's definitely warm it up as well.
 
napalmdeath":172aqc0k said:
Had 2 JVM205H's. YES, they are noisy. Noisiest amp I've ever owned. ISP Decimator, that cut it more than in half. Couldn't live without with either one. Without it, I wouldn't be able to stand the white noise/hiss.

I recommend JJ KT77's, and a mix of pre's. My best luck was the KT77's, Tungsol in V1, JJ ECC83S in V2 & 3, C9 in V4, and a balanced JJECC83S in the PI. JJ's are not for everyone, obviously, but the KT77's sounded better - warmer, and tighter than the SED's I had in both. Svetlana EL34's sound good too. For a New Sensor/Sovtek-made tube, they are warmer than the SED's as well. GREAT tube.
The ECC83S's definitely warm it up as well.
Click to expand...
This is what worries me about my impending 210H deal. I'm used to noisy amps and taming them though, so I guess should be fine (?) I use an NS-2 in the loop of my UL and a Decimator in front.
I use a Decimator in front of my Recto, 6505, Avenger, JSX, GH50L too.
My 2203KK and ENGL have built in gates. But I still gate the front of my ENGL with a Decimator because the built in gate is after the preamp, so it eliminates all the hiss and shhh you inherently get with super high gain amps but not the front end pickup/electrical noise.

I keep my ISP set conservatively, below half. 4/10 I'd say. So I don't have any noise problems per se, my signal is just generally absolutely or near absolutely silent.
I typically play loud. High master's, pant flapping, you know...
So the gates just make playing at those levels more enjoyable.

My 2203KK has the best gate though by far.
Marshall should grab a brain and develop a noise reduction pedal already. It sure gives ISP a run for their money, that's for sure.
 
napalmdeath":2e8x1iks said:
Had 2 JVM205H's. YES, they are noisy. Noisiest amp I've ever owned. ISP Decimator, that cut it more than in half. Couldn't live without with either one. Without it, I wouldn't be able to stand the white noise/hiss.

I recommend JJ KT77's, and a mix of pre's. My best luck was the KT77's, Tungsol in V1, JJ ECC83S in V2 & 3, C9 in V4, and a balanced JJECC83S in the PI. JJ's are not for everyone, obviously, but the KT77's sounded better - warmer, and tighter than the SED's I had in both. Svetlana EL34's sound good too. For a New Sensor/Sovtek-made tube, they are warmer than the SED's as well. GREAT tube.
The ECC83S's definitely warm it up as well.
Click to expand...


I was under the impression that "S.E.D." stands for "SVETLANA electrical devices"...?
 
D-Rock":2cxba5p6 said:
napalmdeath":2cxba5p6 said:
Had 2 JVM205H's. YES, they are noisy. Noisiest amp I've ever owned. ISP Decimator, that cut it more than in half. Couldn't live without with either one. Without it, I wouldn't be able to stand the white noise/hiss.

I recommend JJ KT77's, and a mix of pre's. My best luck was the KT77's, Tungsol in V1, JJ ECC83S in V2 & 3, C9 in V4, and a balanced JJECC83S in the PI. JJ's are not for everyone, obviously, but the KT77's sounded better - warmer, and tighter than the SED's I had in both. Svetlana EL34's sound good too. For a New Sensor/Sovtek-made tube, they are warmer than the SED's as well. GREAT tube.
The ECC83S's definitely warm it up as well.
Click to expand...
This is what worries me about my impending 210H deal. I'm used to noisy amps and taming them though, so I guess should be fine (?) I use an NS-2 in the loop of my UL and a Decimator in front.
I use a Decimator in front of my Recto, 6505, Avenger, JSX, GH50L too.
My 2203KK and ENGL have built in gates. But I still gate the front of my ENGL with a Decimator because the built in gate is after the preamp, so it eliminates all the hiss and shhh you inherently get with super high gain amps but not the front end pickup/electrical noise.

I keep my ISP set conservatively, below half. 4/10 I'd say. So I don't have any noise problems per se, my signal is just generally absolutely or near absolutely silent.
I typically play loud. High master's, pant flapping, you know...
So the gates just make playing at those levels more enjoyable.

My 2203KK has the best gate though by far.
Marshall should grab a brain and develop a noise reduction pedal already. It sure gives ISP a run for their money, that's for sure.
Click to expand...

I would be of contrary opinion to this. I don't think the JVM is noisy I don't use a noise gate with mine, doesn't warrant needing one. Know people who regularly gig with them and crank the volume with no noise issues. They sure like their gain too!

My Mesa Mark III was way noisier!
 
Charvel_King":3arx8kbx said:
D-Rock":3arx8kbx said:
napalmdeath":3arx8kbx said:
Had 2 JVM205H's. YES, they are noisy. Noisiest amp I've ever owned. ISP Decimator, that cut it more than in half. Couldn't live without with either one. Without it, I wouldn't be able to stand the white noise/hiss.

I recommend JJ KT77's, and a mix of pre's. My best luck was the KT77's, Tungsol in V1, JJ ECC83S in V2 & 3, C9 in V4, and a balanced JJECC83S in the PI. JJ's are not for everyone, obviously, but the KT77's sounded better - warmer, and tighter than the SED's I had in both. Svetlana EL34's sound good too. For a New Sensor/Sovtek-made tube, they are warmer than the SED's as well. GREAT tube.
The ECC83S's definitely warm it up as well.
Click to expand...
This is what worries me about my impending 210H deal. I'm used to noisy amps and taming them though, so I guess should be fine (?) I use an NS-2 in the loop of my UL and a Decimator in front.
I use a Decimator in front of my Recto, 6505, Avenger, JSX, GH50L too.
My 2203KK and ENGL have built in gates. But I still gate the front of my ENGL with a Decimator because the built in gate is after the preamp, so it eliminates all the hiss and shhh you inherently get with super high gain amps but not the front end pickup/electrical noise.

I keep my ISP set conservatively, below half. 4/10 I'd say. So I don't have any noise problems per se, my signal is just generally absolutely or near absolutely silent.
I typically play loud. High master's, pant flapping, you know...
So the gates just make playing at those levels more enjoyable.

My 2203KK has the best gate though by far.
Marshall should grab a brain and develop a noise reduction pedal already. It sure gives ISP a run for their money, that's for sure.
Click to expand...

I would be of contrary opinion to this. I don't think the JVM is noisy I don't use a noise gate with mine, doesn't warrant needing one. Know people who regularly gig with them and crank the volume with no noise issues. They sure like their gain too!

My Mesa Mark III was way noisier!
Click to expand...
Same here, I've owned two as well...still own one and it's been my main amp for years. I do not use any type of noise reduction. Never needed it. Not debating whether some guys have had noise issue with them...I just know I have not.
 
I've owned 2 JVM's and both were very noisy, the main reason I sold them...tried different tubes, guitars, etc...hiss and very prone to squealing, even under just moderate gain levels. The most likely cause of the no midi communication with the GCP is the midi channel setting, or possibly a bad midi cable...
 
We are going to go through mine this weekend. I bought a brand new set of EL34s and ECC83s JJ's, going to REMOVE the plexi cap. The amp also has negative feedback mod.

When it comes to the noise problem, it's not so much hiss as it is excessive feedback. That's what's making me think I have a bad tube. The JVM i played at GC (in the back at high volumes) never had this much noise or feedback even without a noise gate.
 
Yeah like i said - mine's pretty quiet actually. How do.you know yours has the negative feedback mod or whatever?
 
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