A collaboration between John Mayer and Paul Reed Smith, the J-MOD 100 was originally born from a need for an amp to take on John’s Dead and Company Tour. Once over, they went back with the prototypes and refined the amp to be an amp to end the search for amps. A lofty goal indeed, especially when Mayer himself reports on his own GAS (gear acquisition syndrome) saying he’s like all other guitar players collection and swapping gear constantly.
At $5,990 for just the head, this is by far not a cheap amp but can it be your last amp? To cut to the end, for me, no it cannot. However it isn’t going anywhere anytime soon as it is probably my ideal second amp, so lets take a look and see what the J-MOD 100 offers and where it comes up short.
When you watch the videos of Paul and John’s release of the amp, and all the demos that came with it, you typically hear two main points be emphasized. They are that the amp is a lot quieter than expected and the “bounce” that John regards so highly with the amp. After playing the amp for a bit I can say that they are definitely both true statements, and are actually closely related.
100 watts of all tube power is typically an ear popping experience that is largely innapropriate for home use, or means you just tickle the volume on to keep from going deaf or annoying the neighbors. But with this amp, you find yourself turning it up way more than would seem reasonable looking at the knob. In comparison, with the J-MOD turned up to half way, I would only need to turn my 40 watt Two-Rock Bloomfield drive combo up to less than a quarter to reach the same volume. And it’s not all down to the pots with the volume jumping in huge leaps in the second half of travel, it’s relatively quiet all the way up.
So where are all those watts going? Are they just getting wasted, turned to hear in inefficient tube layouts? Not at all, all of those watts are going to the “bounce” we have heard so much about. You see, Paul and his team have managed to pack an insane amount of bass end into this amp and cab, and many of those watts are being used to support that bottom end to allow it to respond as quickly as the rest of the frequencies. There really is a bounce, an urgency, or a cleanliness to the bass response that seem to never flub out regardless of how high the volume or bass eq is turned.
But it’s not all good. Balancing the overdrive setting with the clean is a difficult process almost always ends in some compromise, much like early Mesa Boogie amps. Often the gain levels in the overdrive “channel” (not really a channel, but another switchable gain stage) are more than I’d want with just enough volume to make up for a low gain setting. It’s not to say I’ve found any setting that didn’t work, it’s just that I’m often right at the end of the pot’s travel with no room left “just in case” I wanted more.
Lastly, I understand that John doesn’t need a reverb built into the amp with his Bricasti near by, but for those of us with a standard pedalboard and no rack effects, it necessitates an awkward decision of either running long cables to put a single pedal in the effects loop, or a separate power supply for one pedal to sit on the amp. This to me, is the main reason why it could never be my only amp. Which is OK. Because it pairs perfectly with my Bloomfield 40 in a wet/dry rig that sounds fantastically epic at any volume, but especially sweet as your turn it up and feel that wonderful bouncy bass in your chest.
Bonus: The J-MOD 100 uses a 5 pin cable for it’s footswitch. If you want to use a pedal switcher (like a GigRig G3 or other similar ones) then you need to make a cable or converter to go from 1/4″ TRS to the 5 Pin connecter. Being the amazing company they are, PRS quickly replied to my questions and the amp tech drew this out to send to me.
