Sunday, October 31, 2010

Here we have a Lafayette branded Univox U50 Bass hybrid amplifier head. It boasts a three input solid state front end feeding a push-pull 6L6 output with 12AX7 phase inverter. The controls, from left to right are: Volume, Bass, Treble, Hi Boost, Lo Boost. This amplifier was bundled with a heap of broken gear salvage operation that occurred last Spring.

Exposing the guts begins to tell a tale, a floating PCB, severed wires, power transformer replacement (and the addition of an Archer lower voltage power transformer wired in with clear jacket lamp wire to serve the needs of solid state). My guess is that if this thing had reverb to begin with they would have gotten around to finding a place for the B+ filtering and rectifier, absent as it stands.

A narrow peek at the pot mounted preamp and tone circuit, I'll probably put those carbon comps and that tropical fish to work elsewhere, this amp is on the gutting path.

Can I have another look at that lead dress? (I must have stopped to ponder this part of the amplifier at least three times)

This reminds me of my first builds. Before I digested the concept of lead dress, or was able to look at other people's work on the internet. I honestly don't see anything redeeming about this amp as stock. While there is evidence of someone else having tampered with this amp in a few ways, my gut is telling me that this wiring arrangement is stock. Obviously, by the early 1970s the notion of quality had fallen by the wayside in a few quarters. Being the sentimental sort, I typically have to do a bit of weighing out before I gut something; this, however, offered no problems on that front. Now it will be testbed to some goofy ideas,and not so goofy ones, such as making use of that dual RCA slot to build in a proper reverb.

Much better.

No comments: