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I live in a small townhouse with 2 shared walls and my 6/4 tuba is a little bit too much for my neighbors. I practice for 1-3 hours a day and can't play any later than 7-ish; I was wondering if there are practice mutes big enough to fit in my horn and quiet enough to please my neighbors. I've seen the Silent Brass systems, but I'm not willing to shell out $500 for something that may not fit/work for me. If anybody has prior experience with this I would like to hear (read) what you have to say.

Thanks, Kevin

Silent brass frequently turns up used. Also, if you buy it you probably don't needs the electronics and can sell that off on da bay to some unsuspecting trumpet player...