Here’s a late 1960’s RCA rack with discrete transistor BA-31B and BA-33B preamps mounted in original trays and wired for power and XLR in/out. All four use a germanium driver transistor. All new caps, front end transistors upgraded to quietest official version, output power transistors in the BA-33’s pulled and cleaned with new thermal grease put in place. I actually had five BA-33B’s side by side during restoration for comparison, always nice to have comparative data. The BA-31B’s have had the gain reworked to be continuously variable from 30-56dB versus the standard 40/46dB fixed gain - you won’t find that from any other source, at least to date. The 33’s are set for 70dB max (continuously variable), which I believe is actually 76dB because of the input transformer being connected for mic use. All test great for response and noise, and have that early ’70’s meaty discrete transistor with (UTC) transformers sound. Great for rock records, I have these on drums a lot. All steel construction, means they are, by nature, heavy metal. $2595 plus shipping and insurance. 37 lbs before packing.
Post by tasteliketape on Oct 18, 2020 18:26:09 GMT -6
I love this pre ! Haven’t done a lot with it but so far acoustic gtr, vocal , Bass all have put a smile on my face thru the Ba33 . I’ve used it with a Samar Mf65, Neumann m582, and a Heiserman 47 cap mics all sounded perfect . The Rca just seems to have the right amount of both weight and color for my taste . Seems very balanced from lows to highs