Official original Marshall JVM appreciation thread

[laxu]

main thing to watch for is if anyone has hacked some mods and made a mess of it.

I think because they can be picked up for reasonable prices sometimes they get treated a bit worse than a “boutique” amp. They’re often great prices here but usually a bit more beaten up cosmetically too.

The one I'm looking at has had a few mods done, but they seem to be some of the simplest and most sensible of the mod list (Plexi, C83, negative feedback mods). Otherwise looks super clean.

These are absolutely not boutique around here, pretty common amp with fairly set prices, which is why I've considered buying one a few times already.

I'll see if it's still available next week when I have a car to use.

 

[cragginshred]

Why didn’t it just come that way to start with?

Great question,.. Jose made a lot of $ in the 80's fixing harsh Marshalls

 

[spawnofthesith]

So, I'm kinda considering picking up a used JVM410 head. They aren't priced too bad over here.

Other than being large and heavy, what are the bad parts of these? I know there's a lot of easy mods to tweak them.

Loop isn’t the best

I actually got better results when I switched to using the other loop that supposedly I wasn’t supposed to use for my applications lol

 

[laxu]

Loop isn’t the best

I actually got better results when I switched to using the other loop that supposedly I wasn’t supposed to use for my applications lol

I guess you mean the loop marked preamp out/poweramp in? How does it work with the fx you use? Since I mostly use Strymon/SA which should be able to take line levels, I should be fine.

Is the main issue with the regular fx loop that it does not go fully series even with wet mix at 100%? Does this cause phase issues or what?

 

[Karl Houseknecht]

Since I mostly use Strymon/SA which should be able to take line levels, I should be fine.

Maybe. I’ve been able to clip the Timeline and BigSky with hot signals like you can get in that poweramp insert loop. Be mindful of your channel volumes by keeping them at 10:00 or lower and you should be okay.

Is the main issue with the regular fx loop that it does not go fully series even with wet mix at 100%? Does this cause phase issues or what?

Yes. You can get phase issues.

 

[laxu]

Maybe. I’ve been able to clip the Timeline and BigSky with hot signals like you can get in that poweramp insert loop. Be mindful of your channel volumes by keeping them at 10:00 or lower and you should be okay.

The older big box Strymons don't seem to have the instrument/line level setting that is found on the newer pedals, including the BigSky MX. While the FAQ says the old ones should accept up to +8 dBu signal, maybe the line level setting on newer pedals helps?

Yes. You can get phase issues.

I guess there's no mod or fix to this, other than using it as a parallel loop, which gets kinda annoying if it's not a single multifx box but multiple pedals since you want kill dry in there somewhere.

 

[Karl Houseknecht]

I guess there's no mod or fix to this

They fixed it on the Satriani model with a good series loop at instrument level. Why Marshall hasn’t updated their flagship since discontinuing the HJS is baffling.

 

[laxu]

After smashing the UAD Lion sim, I spent some time with the JVM OD1 channel today and did some captures. ToneX and NAM came out extremely close to the OG amp. I'll eventually do a full pack but I don't want to rush it / get annoyed / feel like I need to redo it. These are +13dBu captures.

Samples


NAM
https://tonehunt.org/AmpsPedalsPickups/6b8be5f7-f030-4503-a89b-965e5bfb3f2f

ToneX

JVM-OD1-Green

Marshall JVM410H

www.tone.net

JVM-OD1-Orange

TONEX Tone Model sharing community

www.tone.net

JVM-OD1-Red

TONEX Tone Model sharing community

www.tone.net

Thanks for the NAM captures!

I was able to use these to get an idea what I would get with the JVM. It sounds great, I think I would like it!

But I ended up saving a bunch of money, because I can dial my BluGuitar to sound pretty close. Not identical, but this was a quick "dial by ear, play a sloppy track" test.

Can you guess which is the JVM?

 

[likitlikeyoulikeit]

Thanks for the NAM captures!

I was able to use these to get an idea what I would get with the JVM. It sounds great, I think I would like it!

But I ended up saving a bunch of money, because I can dial my BluGuitar to sound pretty close. Not identical, but this was a quick "dial by ear, play a sloppy track" test.



Can you guess which is the JVM?

Do you work for Blug?

You bring it up ALL the time.

 

[laxu]

Do you work for Blug?

You bring it up ALL the time.

Nah, it's just the only amp I own anymore!

So everything gets compared to it, and if I can dial the BluGuitar to sound similar, then it's "eh, don't need to buy anything".

 

[[Nathan]]

Thanks for the NAM captures!

I was able to use these to get an idea what I would get with the JVM. It sounds great, I think I would like it!

But I ended up saving a bunch of money, because I can dial my BluGuitar to sound pretty close. Not identical, but this was a quick "dial by ear, play a sloppy track" test.

Can you guess which is the JVM?

First one has a bit more girth so probably the Bluguitar . It’s just us nerds that sweat the difference, so much real world overlap both sound great

 

[MirrorProfiles]

Thanks for the NAM captures!

I was able to use these to get an idea what I would get with the JVM. It sounds great, I think I would like it!

But I ended up saving a bunch of money, because I can dial my BluGuitar to sound pretty close. Not identical, but this was a quick "dial by ear, play a sloppy track" test.

Can you guess which is the JVM?

I like the 1st one better, more girth, more gain, less pokey in the upper mids. Could just be how things are dialled in though. I'd also prefer them without the room sound on it I think

 

[laxu]

I like the 1st one better, more girth, more gain, less pokey in the upper mids. Could just be how things are dialled in though. I'd also prefer them without the room sound on it I think

That's the BluGuitar. It ended up a bit different and could be probably dialed even closer with some tweaks. But I think they are close enough in the same ballpark that it doesn't make a whole lot of sense to buy a JVM. Even though the separate channels each with their own EQ would be nice. The BluGuitar works best as a switchable voicing single channel amp, or at most a dual channel clean/drive amp.

Room reverb was mainly to make them sound more pleasant into my headphones, I'm still working out how to get the best results out of the UA Sound City when used as room reverb. Not the best option for comparing for sure.

 

[texhex]

Pretty nice JVM demo here. Only thing he could have done better I think is show off the Crunch Orange and OD-1/2 Green channels lower gain potential. Otherwise this is a great representation of how this amp sounds. Sorry JT... GAS inducing video incoming!

 

[KingsXJJ]

For me what Tom Cruise said about Porsche’s in Risky Business applies to the JVM.

 

[KingsXJJ]

Pretty nice JVM demo here. Only thing he could have done better I think is show off the Crunch Orange and OD-1/2 Green channels lower gain potential. Otherwise this is a great representation of how this amp sounds. Sorry JT... GAS inducing video incoming!

The Bonus Tip for Plexi style tones at 27 minutes is a new one for me! Thanks!

 

[Eagle]

Loop isn’t the best

I actually got better results when I switched to using the other loop that supposedly I wasn’t supposed to use for my applications lol

The trouble is not the loop it's the fact that a lot of new FX doesn't have a control for input gain, or a clip light to maximise the S/N ratio. Most so-called universal input pedals don't handle a proper +4db line level without clipping and sound worse at -10db. If you use a Lehle parallel 2 loop insert pedal you can mix the fx with the dry analog signal and also get a gain control for in and out of any FX matching both amp and FX for optimum performance. Just like ANY rack processor had in the past.

 

[spawnofthesith]

The trouble is not the loop it's the fact that a lot of new FX doesn't have a control for input gain, or a clip light to maximise the S/N ratio. Most so-called universal input pedals don't handle a proper +4db line level without clipping and sound worse at -10db. If you use a Lehle parallel 2 loop insert pedal you can mix the fx with the dry analog signal and also get a gain control for in and out of any FX matching both amp and FX for optimum performance. Just like ANY rack processor had in the past.

Maybe so, but I've had dozens of different tube amps over the years and the only one's that ever gave me much trouble for basic basic level of fx loop operation were the JVM and the Rectoverb 50 (rectoverb was much worse than the JVM though so I'll give it that lol)

 

[Leperclown]

Hi all, I had a JVM 410 + 4x12 & 2x12 cab 20 years ago and loved it. I got rid of it to get more into modellers (!).

I sure missed that amp (especially the Crunch channel cranked).

Four years ago I bought a JVM410C (hellishly heavy) but sounds awesome (after a fair bit of tube rolling and experimenting with bias).

I run it alone with a Decimator G String or in 4CM with a Boss Gt1000.

A couple of thoughts:

• The Decimator G String (before the amp and in the loop) does a great job of quietening down this beast
• The two NR units (input and after the JVM) in the GT1000 work pretty well
• Using a Multi FX unit in 4CM (+midi) allows you to use the loop levels in the MFX to balance the volume levels between modes in the same channel, allowing access to all 12 modes without volume inconsistency
• If the MFX has adjustable Guitar / Line levels (as the Boss GT series does) the serial loop works better than the 'parallel to serial' loop
• Did I mention the combo is heavy? tried a couple of Neos (Celestion Neo V type) they sounded ok but didn't really make a significant weight difference so I swapped the originals back in
• I had my previous 410 head modded to allow external bias test & adjustment. Best move ever and I am going to do this to the combo (eventually). Should be be a standard feature in all amps!
• The best gigging setup (sound / portability compromise) is the 410 head + 2x12 cab (or 2 2x12's if required)
• Aside from portability issues, the JVM is a great gigging amp as the Master Volumes work brilliantly across all volume ranges
• In Australia, JVM's can be bought relatively cheaply (I imagine people are exiting the big heads and heavy combos in favour of modeller + "FRFR")

Cheers!

Paul

 

[[Nathan]]

Hi all, I had a JVM 410 + 4x12 & 2x12 cab 20 years ago and loved it. I got rid of it to get more into modellers (!).

I sure missed that amp (especially the Crunch channel cranked).

Four years ago I bought a JVM410C (hellishly heavy) but sounds awesome (after a fair bit of tube rolling and experimenting with bias).

I run it alone with a Decimator G String or in 4CM with a Boss Gt1000.

A couple of thoughts:

• The Decimator G String (before the amp and in the loop) does a great job of quietening down this beast
• The two NR units (input and after the JVM) in the GT1000 work pretty well
• Using a Multi FX unit in 4CM (+midi) allows you to use the loop levels in the MFX to balance the volume levels between modes in the same channel, allowing access to all 12 modes without volume inconsistency
• If the MFX has adjustable Guitar / Line levels (as the Boss GT series does) the serial loop works better than the 'parallel to serial' loop
• Did I mention the combo is heavy? tried a couple of Neos (Celestion Neo V type) they sounded ok but didn't really make a significant weight difference so I swapped the originals back in
• I had my previous 410 head modded to allow external bias test & adjustment. Best move ever and I am going to do this to the combo (eventually). Should be be a standard feature in all amps!
• The best gigging setup (sound / portability compromise) is the 410 head + 2x12 cab (or 2 2x12's if required)
• Aside from portability issues, the JVM is a great gigging amp as the Master Volumes work brilliantly across all volume ranges
• In Australia, JVM's can be bought relatively cheaply (I imagine people are exiting the big heads and heavy combos in favour of modeller + ""FRFR"")

Cheers!

Paul

A couple months ago I picked up a JVM410H and instantly I was like.... this is the Marshall I always wanted. I'd gigged a TSL100 for 10 years, had it in the studio. For my taste there was always these tight sweet spots, would go from too thin to farting out on high gain stuff. The JVM can do its thing on every mode on every channel. I need to spend more time with it but I'd encourage anyone under the age of 50 wanting a marshall to just shoot straight for a JVM instead of a DSL/TSL or other cheaper ones