
Improving a CRATE BX-15 Practice Amp from my "review" at Harmony Central.
Here is the reason why I'm reviewing this amp. The speaker is a dinky one. The cabinet is devoid of absorvent material. There is a vent hole in the front panel but no vent tube attached. This is a poor design that the amplifier does not deserve, even a 15+- watt one.
So the first thing I did was use the white stuffing that was used to line a sofabed. Safer than fiberglass and just as good at attenuating the internal wave from the speaker. Then I tried to find a hard cardboard tube wide enough to insert into the hole which could stay without glue but I would use glue anyway for stability. I didn't find one so I got a slightly wider one and cut its length to an inch short of touching the back. I glued it in place and to make sure it didn't sag while drying I put a support under it to keep the round edge against the wood.
Finally, and the best part, I wanted to replace the speaker with a better quality speaker with possibly a rubber surround and heavy magnet. I preferred a magnetically-shielded speaker so I kept my eye out in the local thrifts for cheap audio speakers. I didn't find any but I did find a SONY subwoofer model SS-S300 that I thought might do the trick. It did it perfectly! The thrift price sticker said $8 but the cashier rang it up and told me $6.50. What a deal!
The speaker has rubber surround, large double-magnet and the best part is that the speaker fit into the cabinet's opening and this was going to be the biggest factor and yet I was lucky to do it right the first time.
Then I tested it and the sound is awesome! You could say it's the PERFECT practice amp if you don't want room-rattling volume. The bass is totally impressive and even a professional bassist would be impressed with this little jewel that now reallyshines.