For characteristics, I refer you to notice NicolasD that is complete. Having bought this amp after multiple test shop (and many other amps) and after setting my needs, I have not had any bad surprise ...

So 10/10

UTILIZATION

By cons, here I'll be more, but I will speak of a''perspective''and not''user''musician, so no comments yet on the sound itself.

I'll start with two flaws:

1) the''modes''of channels: the channel Gold, you can have clean or crunch mode which are both beautiful to cry! and unfortunately, they are not foot switchable, but through a switch in the microscopic volume pot and that's really bad! However, this is a fault which I was fully conscious when buying (it's a 2 channel, not a 4!) And I would say there are lots of ways around (a TS- like upstream, lower the volume of the guitar to return to almost-clean ... etc.)
2) The effects loop is parallel is described as a quality in the manual. Indeed, the signal never leaves the amp, so no loss or corruption''''signal ... But yes! Me that I have a serious problem using my JAMMAN ... I have a concern for signal level as well as it exits the amplifier to JAMMAN (too loud) when it returns from JAMMAN to the amp (too low) despite the settings JAMMAN .. . moreover, there is only one volume pot mix adjustment of the loop (and not one on one on the SEND and RETURN). Well, I'll work on it and see if I can find a solution ...

Now the qualities (and there are many):

1) the supplied footswitch! 4 buttons (channel, boost, reverb, delay): solid as a tank (to see over time), connected via an XLR cable (and thus replaceable): in a word: awesome!
2) The settings are hyper-efficient, including EQ and 4 switches (2 x bright, deep and midshift) and sweep a large repertoire
3) mode 20W/40W: very handy (there really, but it is only my opinion, a difference in volume)
4) A standby, it sounds stupid, but the amps from 20 to 50 watts are not all filled ...
5) connection to the cabinet expansion
6) the presence of reverb and delay: super convenient! My pedalboard will be severely Reduce!

Otherwise, the manual is clear and explicit, nothing to say.
Do you get a good sound easy? See the next paragraph!

So 6 / 10 for now, 9 / 10 if I can solve this history effects loop

Update 08/20/2010: Okay, now for the famous effects loop, I managed to get used to it, but it is not obvious. Firstly, I had to adjust the volumes of input and output of my JAMMAN so "unbalanced" output volume to 3 / 4 and input volume barely half (it changes my uses earlier). Furthermore the effects loop can be used to "thicken" the sound (especially in crunch mode on channel gold): a ts-like or OD will make the sound fatter, more "full", in fact, not only was the original sound, but the sound through the OD +

In short, I am much happier with the effects loop so that at first I was the score at 8

SOUNDS

Note: for now, I have not tested by repeating, I'll update when this will happen!

So I play blues, hard rock, to rock, garage, a little pop. I love Led Zep, ZZTOP, jack white, but also lots of other stuff!
I play on Start (Mexico) with noiseless pickups on my first electric guitar I've customized (one with 2 humbuckers Squier home GFS VEH) and also with a mini humbucker dbro. Some effects: TS-like, big muff, wah-wah ...

I'll avoid giving you 8000 adjectives describing the sound: if you want to know how it sounds: you have to try it with your gear and your fingers!

Personally, for me the clean, the switch''bright''makes pretty things.
Crunch mode is my favorite: great, huge, living, terrible!
Channel Mercury is currently less exciting: very dull with the EQ at noon, we must drastically cut the bass ...

I'll update the review after a few Repeat '

if I did note that the crunch, 9 / 10, but more generally: 8 / 10

OVERALL OPINION

I use it for 2 weeks and I will update my review when I had more experience with ...

Before the purchase, I tried:
Marshall JCM 900 dual reverb: Well, nothing to say!
Kustom Coupe 76 ': terrible, but less versatile, and mostly sold at prices prohibitive to store (unlike Thomann ...)
Fender Blues Deluxe edition reissue normal, clear sounds wonderful .... and then voila!
Orange tiny terror: a crunch!! but nothing else!
Vox night train: ditto!

The value price is right, I paid € 830 in store (available for less at € 70 thomann), once again, I do this after a lot of research, so if I had not seen the correct value for money, well I will not get it made!

For now 7 / 10 due to the effects loop, to do with a bit more perspective ....

Update 08/20/2010: I use the effects loop finally meet me, I go back to the overall opinion 8. In addition, I planned a time to sell, well, actually not, I care! all that to say that it is not necessarily easy at first, it takes patience and a lot of testing ...