>Your observations are very interesting. I would love to hear more
>about a speaker "isolation" cabinet and perhaps live aplications for this
>setup using say a Marshall or similar type of tube head.
Demeter makes the only mass-produced full-scale speaker isolation cabinet. Other companies could custom manufacture these. I built my own, but I would rather buy a mass-produced unit. Guitarists shouldn't waste time building their own. My materials cost some $300. I made a large box out of 3/4" fiberboard. That was still too loud. I made a larger box out of 3/4" fiberboard. You can only hear the lowest bass leaking through.
Any 15 watt tube amp should do a fine job of pushing a Celestion Greenback guitar speaker ($100 12" 25 watts). A Shure SM57 is good for exterminating any remaining high frequencies to get a real British tone. You might be able to put a sturdy condenser mic in the box.
To use a Marshall head instead of a 15-watt combo amp to drive the speaker isolation cabinet, use a speaker that can handle 100 watts. It's a pain if you fry it, and you will be driving it very hard. In my first experiment with an isolation cabinet, I fried a good speaker in a few minutes, with a transistor amp.
I built my own computer-fan-on-a-stand to cool the power tubes.
I'm commited to the idea of speaker isolation cabinets. It's the only no-tonal-bullshit approach to quiet cranked amp tones on tap. I just can't settle for a "close approximation" of a cranked tube amp.
Here are some sample products -- all of them available through mail order, and many on the Web.
o Digitech 2112 effects unit
o Marshall 100 watt tube head
o Demeter speaker isolation cabinet
o 100 watt Celestion guitar speaker
o Shure SM57 dynamic mic
o Digitech 2101 effects unit
You also need to have:
o Power amplifier
o Full-range monitor
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