Weber Mass- Weird Issue

LooseCannon · Post by **LooseCannon** » 06 Sep 2011, 15:46

Hey guys, I got the Weber MiniMass 50 today, i'm plugging it between my AC15 set on 8 ohms and an 8ohm 2x12 cab.

When I set the MiniMass on 8ohms, the tone gets muffled, even on minimum attenuation, the amps loses its brightness and the rich open tone, the treble switch doesn't compensate for this.

However, when I tried switching the weber to 16ohm, the tone got much clearer and closer to my amp's tone.

So how do you explain this weird issue? Will I be hurting my amp if I run the weber on 16 ohm?

I've read an article on aikenamps.com about attenuators which says there's no such thing as "one fits all" attenuator (regarding ohms), and that the impendence actually changes as the amp's volume and the attenuation level changes, could this be related to what i'm hearing? See this chart for example: http://aikenamps.com/Airbrake_impedance.jpg

Thanks

Hides-His-Eyes · Post by **Hides-His-Eyes** » 06 Sep 2011, 15:55

While I don't know anything specifically about the output transformer in that amp and so can't say so in a binding way, a load impedance twice that expected is usually fine, although may result in some attenuation (not a disadvantage in your case!)

LooseCannon · Post by **LooseCannon** » 06 Sep 2011, 18:05

That's the weird thing, the 16ohm setting on the weber is actually a bit louder than the 8ohm.

DougH · Post by **DougH** » 08 Sep 2011, 15:43

I would contact Weber and ask them about it.