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. This is a one stop shop for the best SS RCA. 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 and they all matched up. 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. Have recently used them for Hammond organ, piano, electric and acoustic guitars with a mix of ribbons and condensers. All steel construction, means they are, by nature, heavy metal.
$2495 plus shipping and insurance. 37 lbs before packing.
$2495 plus shipping and insurance. 37 lbs before packing.
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