I play Fender amps (clean) and a Barber Direct Drive (at a medium Drive setting, which is not very saturated- still lots of clean detail) IMO is very good at transforming my amp into a chunky non-MV Marshall-like sound. No bass loss, no fizz, just a great crunch with some nice sustain.
i get a very Marshally tone from my Menatone King of the Britains & my Wampler Triple Wreck gets me firmly into Mesa territory. not sure if either are "closest" as there is a sea of pedals out there, but i'm very happy with both.
This one is as close as I've heard. Clean sound too to the degree it replicates that low mid thumpiness in the voicing and also the very touch-sensitive transition to clipping. This demo has it running through a Vibrochamp and mic'd at a distance to give the viewer an impression of what the amp and pedal actually sound like in the room.
This is what menatone really does best. How successful you will be depends on the base tone that you're starting with, and speaker choice is very important. Sometimes you can play through a speaker that has so much of its own character that it doesn't matter what pedal you use it all ends up sounding the same. I highly recommend the Menatone line. Just pick your favorite flavors.
Wednesday I went to a jam session at my friend's studio. I plugged my Gretsch Jet into my Barber Small Fry then direct into the board. Added a bit of verb to the signal and it was awesome. The SF has a "Dynamics" knob that can be used to add a bit of compression to the signal even at low gain settings. Honestly, it was great and I felt much better about the jam given my friend did not want to use amps.