I tested the attenuator with two different amps (Marshall JMP and ENGL E650), through the same cab (Marshall 4x12).
Pros:
- it's built well, looks solid;
- it can support amps with higher power;
- it has a fan (but I don't think it is really necessary, during my test, the attenuator remained cool);
- it has a selectable impendance 8/16 ohms and a line out;
- it can go to zero.
Now, the cons:
- it drastically modifies the response of the amp - the punch is gone;
- you have to compensate with the eq of the amp;
- it robs any amp of its harmonics.
I had to return it. I also have another attenuator, which I borrowed from a friend. I won't say the name of the brand here. But it costs 6 times as much. That attenuator really makes a difference. If you care about your sound and how it feels when you are playing it, you have to look elsewhere. If you are on a budget, you can be happy with this Harley Benton. I really think this company has made big steps and improves constantly.