John Mayer Signature Amp - The J-MOD100

While I've always wondered "why" I don't find it that curious overall. I've not played nearly the amount of amps that some of you have but have seen almost unbelievable variances in volume output from amps rated the same or similar powers. The first place I always look is the volume pot. Many amps that people SAY aren't as loud may actually be as loud but might have a better smoother volume pot taper. Some amps are full volume at 4 and only compress more and more after that were a comparably rated amp might get louder and louder all the way up to 8 or even 10.

That said, after that's accounted for, there are clear differences in amps rated the same or similar power. My Mesa Mark V is a BEAST of an amp. I can't even think about turning it up half way at home. The Archon is rated half that power, so in theory 3dB less volume. I play it halfway up when the wife is not home. Not for long. But I do. If I turn the V up halfway pictures are falling off walls 3 rooms away.
 
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That said, after that's accounted for, there are clear differences in amps rated the same or similar power. My Mesa Mark V is a BEAST of an amp. I can't even think about turning it up half way at home. The Archon is rated half that power, so in theory 3dB less volume. I play it halfway up when the wife is not home. Not for long. But I do. If I turn the V up halfway pictures are falling off walls 3 rooms away.

So true!

My Mark V was a beast, and my Lone Star is only run at full power when I absolutely need lots of headroom; I’m usually at 50 Watts, and sometimes at 10 Watts. Of course, the amp sounds different at each power setting, so there’s that.

I find 30 Watts to be pretty good in the studio, but heck, a 30 Watt Vox can get insanely loud!
 
Also the overdrive on it is trash.
First of all, you have access to that amp. While I only estimate on what I have seen in videos.

That said, yes, the overdrive seems to be "somewhat special". But eg. in the Sweetwater video, you hear it isn't especially suited to lead playing. But it comes to life as soon as more than one string is played. So I assume it would be great for playing ZZ Top like riffs.
 
One thing I’ve learned about amp overdrive is that one player’s “great” is another player’s “sucks,” because each of us likes/wants to hear different tones.

I think the HXDA has the best overdrive of any amp I’ve owned. But I have also gotten PMs from folks telling me they don’t care for it at all. Well, what can ya say? They’re not any more wrong than I am; tone is subjective. There are plenty of amps others love - Friedman’s Marshall style amps, and many JCM 800s are examples that come to mind - that I could never live with.

This, to me, is as it should be. I don’t want to sound like anyone else, and I’m guessing lots of other players feel the same way!

One thing about Mayer’s rig is his use of the Bricasti M7 reverb, a rackmount unit that costs 4 grand. It’s one of those boxes you see only in higher end studios, and it’s sound quality is extremely top-drawer. A unit like that reminds me of the Eventide H3000 d/se I used in the 90s in my amp’s loop for reverbs and delays, a fairly equivalent piece for its era. In any case, it’s hard to come to conclusions about one piece of gear that’s designed to be used in conjunction with another piece of gear unless you have both.

I do still want a JMOD, so I guess we’ll see how things shake out once I finish redoing my studio space over the spring and summer.
 
Don't get me wrong, the overdrive can be made to sound good, but you need to keep the drive down and the bass below a quarter. Issue is, the shared EQ then means the clean tones suffer.

That being said, the clean is phenomenal, and the real reason anyone buys this amp anyway. I took my pedalboard out the signal path recently, went straight in, bit of reverb from a BigSky, beautiful.
 
Don't get me wrong, the overdrive can be made to sound good, but you need to keep the drive down and the bass below a quarter. Issue is, the shared EQ then means the clean tones suffer.

That being said, the clean is phenomenal, and the real reason anyone buys this amp anyway. I took my pedalboard out the signal path recently, went straight in, bit of reverb from a BigSky, beautiful.

Yeah, I agree it’s mainly about the cleans, from what I can hear in clips.

Since my work is in the studio, resetting the EQ isn’t a big deal; my “issue,” if there is one, is that lately I’ve used a Mesa Lone Star as my “Blackface clean” tone, and I wonder if I truly need a JMOD. I guess the way to know is simply to play one, something I plan to do in the near future.
 
Anyone else find this amplifier borderline ridiculously quiet?

I play it at 1/3rd volume at home, and can turn up to half without any fear of noise complaints!

So - for a long time I've talked about, and somewhat complained about how quiet the JMOD is. I play it at about 1/3rd volume at home, whereas most amps I play at well below a quarter. So today I decided to get a decibal meter and actually test how quiet it is in comparison to my Two-Rock JM Sig.

The Two-Rock JM sig is a monster and feels very loud (I can't push it up above 1/4 volume without complaints...) But here are the findings of my test.

First - how I did it. I recorded a loop which I fed into each amp, so I had absolute consistency as to the input volume. I set both the JMOD and the JM sig to half gain (there may be differences here - I don't know) and then tested the volume on 1/4, 1/2 and 3/4.

To compare, the JM Sig on 1/4 is around the same as the JMOD on half volume, so you can see where I got my views around the JMOD being so quiet.

However, the JM sig stops getting that much louder past half volume, whereas the JMOD has a pretty level volume sweep all the way up. The JM Sig actually starts to break up a little when it's at 3/4 volume, whereas the JMOD remains completely clean throughout the sweep (which I love).

At 3/4 volume both amps were remarkably similar on the decibal meter. I pushed the JMOD to full volume from 3/4 and it did get a little louder, definitely louder than the JM sig on 3/4.

So I have to take back what I said really! The JMOD isn't quiet by any means, it's just tuned differently. It has a pretty equal sweep throughout the movement of the volume know, whereas most of the JM Sig is tuned in the first half, with only some additional volume above half.

When you compare JM's settings that he ran on the JM sig to the JMOD, theres no doubt he was running the Two-Rocks louder though. Both the volume and gain were at about 2 o'clock when he ran that amp, whereas with the JMOD the gain is slightly below half and the volume about 2'olock also. Still pretty loud, especially if the loop is engaged with the send/return up higher, or with a Katana out front.

I just love the immediacy of the JMOD, so so snappy and fun to play.
 
Oh man I'd love a Super Eagle as well, they're just beyond expensive. One just sold pretty cheap in the UK, if only I had the cash at the moment!

Do you know what it went for? I’ve been haggling with several private sellers for months and just can’t get a deal done. The listed prices keep rising in Reverb but there are no sales. People just see $17k and think that’s what these are worth. Holding out hope for a SE III at this point.
 
Do you know what it went for? I’ve been haggling with several private sellers for months and just can’t get a deal done. The listed prices keep rising in Reverb but there are no sales. People just see $17k and think that’s what these are worth. Holding out hope for a SE III at this point.

Last eBay post was at £8,750. Imagine the bloke sold it for a bit less off ebay.

https://www.ebay.co.uk/itm/302694781725?ViewItem=&item=302694781725

It had been listed for several weeks at around that as well, without any luck.
 
Last eBay post was at £8,750. Imagine the bloke sold it for a bit less off ebay.

https://www.ebay.co.uk/itm/302694781725?ViewItem=&item=302694781725

It had been listed for several weeks at around that as well, without any luck.

Interesting. I “won” an action from a Canadian seller for $9,700, but it didn’t meet reserve. I’m a big believer that an item is worth what someone is willing to pay, but I also get that folks that own a guitar this expensive are not itching to move it at a loss.
 
So I have to take back what I said really! The JMOD isn't quiet by any means, it's just tuned differently. It has a pretty equal sweep throughout the movement of the volume know, whereas most of the JM Sig is tuned in the first half, with only some additional volume above half.

I figured you'd come to this conclusion. There are many amps that hit full volume before half way up on the volume knob and then only compress more and overdrive more after that. My Classic 30 went form barely audible to almost too loud for home in about 1/16" movement on the volume knob. Balancing it "just right" might get you usable volume. It then hit max volume around 5 and only got more compressed and overdriven above that. While Two Rock is certainly well beyond "trickery" I learned a long time ago not to be fooled by varying volume pot sweeps. In most cases, it's by design.

This is also one of the problems faced by amps that have multiple "voices," for example some of the Mesa stuff. When you basically have 3 completely different voices and circuits on one three way switch on one channel, finding the right volume pot taper for all three is always a compromise.

What you found here is generally true: Amps that are designed to stay clean all the way up, have real volume sweep all the way through the range. Those designed to compress and overdrive some or a lot, hit max volume much earlier on the knob and then add that OD as the pot goes up from there. The pots are chosen one way or the other based on what the designer wants. So neither is wrong or write, but if one wants or doesn't want some OD out of the clean channel, then certainly one is better than the other for that user.
 
I'll admit I haven't been paying much attention to the live streams, so this is probably not new news, but looks like JM has put the JMOD away in exchange for three Fender deluxes....

[UPDATE: looks like I missed a big thread on TGP about it. https://www.thegearpage.net/board/index.php?threads/john-mayer-w-dead-all-fender-amps.1947894/


I’d imagine there will be lots of amps used, depending on the venue, the mood of the moment, etc. In a video Mayer himself posted, he mentioned that the Silver Sky was a good match for a Deluxe.

You see him use several guitars; I’d imagine that he’s no different from the way I am. There are days I want to play the DG30, and days I want to play through the HXDA, and still other days I feel like the Lone Star.

Doesn’t mean I’ve put any of them away in exchange for any other. It just means that on that day, the amp I use is what I’m in the mood to use. Just because I use an amp doesn’t mean I’m married to it. I use several amps. It’s more fun/interesting/inspiring that way.
 
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Hi so I've been checking out the Jmod 100 and the Two Rock Classic Reverb Signature. I went back on this thread and read some of the comments regarding the two amps so I have a general idea of the consensus on this thread but I still haven't made my mind up on which one would suit me better. Has anyone else bought a Jmod and is it worth it?
 
Hi so I've been checking out the Jmod 100 and the Two Rock Classic Reverb Signature. I went back on this thread and read some of the comments regarding the two amps so I have a general idea of the consensus on this thread but I still haven't made my mind up on which one would suit me better. Has anyone else bought a Jmod and is it worth it?
Yes and yes. And put a Big Sky in the effects loop.
 
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