1 Watt all-tube'''': 2 x ECC83 and 2 x ECC81
Tone controls, Treble and bass
Switch Mode Power'' Low'' which allows to pass from 1 to 0.1 Watt
Boost Gain on the rear panel
Speaker output 8 and 16 Ohms
No effects loop
The configuration is very simple, you plug it sounds.
With only 3 buttons, the settings do not take 40 years, however, the settings are very effective and very well affect the sound.
Note that this is an old config, ie the level of distortion that is via the volume, as is the case on the Class5 example.
With the volume below 4 it remains in clear sound, one passes over a light crunch to the famous plexi to 8/9.
You long dreamed of the sound of the 70's plexi famous for playing in a small room, the JMP-1 is made for this, but ...
Because there is a but, as when we play it in his clear all goes well, we get a sound very vintage, very endearing, with a telecaster for example, it's great.
on the other hand to enjoy his plexi, there is a small problem, let me explain:
Position 1 Watt power is present, very present, and unless they are sourdingue or play in a basement, your little ears will quickly remind you to order.
0.1 watt position, we have the opposite problem, as it can give pleasure to your neighbors as you hear your strings + that amp, but this plant before the cab or HP does not move an inch .
So there is a hand, too much / too can can disappoint.
Once this problem is solved (I will explain later), then the sound is much sought it, and for that reason alone we can say thank you to Marshall for doing so.
I have my assistants JMP-1 a small attenuator P & P found in secondhand 60/70 Euros, thanks to this little orange box I take 100% of my JMP-1, and believe me, I do not regret a single second. If you want the AC / DC to play backtracks on at home, the triplet JMP-1/SG/Greenback Heritage will take you to nirvana.
Some say that the price is too high, I can understand the criticism, especially since the amp is not perfect, but it is beautiful, it sounds, well it respects its elders glory, then it is expensive but the watt it's so good ...