Homemade Bass Amp

I wasn't too happy with the sound of my '96 Marshall vs65 - its a hybrid, not a true tube amp, and it had lots of hum in the clean channel (not related to volume) and no bottom end. This was a pawn shop beauty, so god knows the abuse it withstood. The 12" Goldback speaker looked pooched, the basket was hammered, and on its way out. I also needed a decent eg, cheap Bass amp to practice in the basement. So, I modified the Marshall. Here's what I did:

1. Replaced the original 15 Marshall ECC 83 tube with an electro harmonix 12AX7r3. It didn't quiet the hum, but sounded a bit better.
2. Replaced the 70 watt 12" Goldback 8 ohm with a 150 watt Eminence Basslite S2012 12” Bass Speaker - designed for a vented (not sealed) cab. The speaker is light using a 4 ounce neodymium magnet. Did I say its light? Somehow this change took care of the hum, and happily, there is a marked improvement to the sound. The bass sounds is crisp, loud, all those good things.

Specs: Nominal Impedance*: 8 ohms. Power Rating**: 150W. Resonance: 48Hz. Usable Frequency Range: 49Hz-4.5kHz. Sensitivity***: 97. Magnet Weight: 4 oz.. Suitable for vented 1x12", 2x12", and 4x12" enclosures.

So, for about $90 CDN after the dust settled, I have what has become a very warm amp. The bass has lots of punch. My guitars sound fleshy through this thing, too - the neck single coil in my x70 sounds fatter. Here's hoping it doesn't blow up in the next week or so ...

The Eminence is priced about 40% of the cost of a Peavey Black Widow. No, it won't push 350 watts continuously but for the basement its fine.





edit: Uh, that'd be a Goldback not Goldtop speaker. Danged senscence.