Musicians Roadhouse

I just acquired a Haze 40. I'm liking it so far. I was wondering if anyone had tried covering the portholes in the back and what effect that might have had. Specifically I'm wondering about increasing the compression and/or what effect on the low end.

This seems likes it's one of the few closed back, or maybe semi-closed back combos, and has potential to play with the overall sounds a bit with covering portholes and/or stuffing with fiberglass like the 4x12 cabs.

Thanks,

Lincoln

I thought I would comment on my own thread since no one else has yet.

So far, it's been what I was hoping. Although the overall volume is reduced, the low end is tigher, there is slightly more compression, and the rhythm is punchier and more percussive. An easier way to say it is that it sounds has more of the characteristics of a closed back cab vs an open back.

Anyone else with experience with this.

Lincoln

Lincoln, your experiment's results are exactly what we would expect, glad you like it. My only concern is the possibility of it now overheating if the amp is designed to use that opening for air circulation of the electrics.
Al

The heat factor did occur to me. Fuarthermore, with the vent on top, and the portholes in the lower part of the cab, I wondered how much of an actual draw effect the heat would create and help cool the tubes. After running the amp for a very long time and building up sufficient heat, I suspended some very light torn tissue pieces in front of the ports, and didn't notice any movement at all. That doesn't mean the holes are significant in helping to cool, but there doesn't seem to be any drafting effect.

So, I located some 60mm rubber plugs that fit perfectly and I'm going to try it for a while. I like the sound. If I run into any problems, I could figure out some kind of small fan like a small square computer fan to put on top to pull hot air out of the top. There is certainly enough that can enter around the other holes in the back of the cab to create sufficient cooling that way.

Thanks for the input.

Lincoln

I'm not so sure about this. It probably depends on the venue. Sometimes the sound gets too small. If you really need to control your sound, it's OK.

Yeah placement in a given room will affect the sound a lot. Open back with a wall behind it or close enough will fill a room more evenly than a closed back which is more directional and focused. The closed back should have more bass though.