I had an idea tonight that I just want to throw out there to see if it’s even possible. So for context. I have 6 x 600:3k Tamura mic input transformers, a decent stash of 2sb737, a couple dozen ztx951, about a dozen 1pole 12 pos rotary switches, and a recent order of 35x NE5534AP. I’m really just wanting to experiment with stuff and build some decent but unique mic pres for my home studio and for device layout practice. So I’m wondering can I set up the input to switch between a transformer based input and a transformerless style input? Can I put that on a pot or a stepped switch to “mix” them into following amp stages without absolutely destroying impedances? I am into the idea of biasing the 5534 into class a with a 4.7k-10k resistor from output to +rail. I’ve also looked into the cascode fet/bjt method which could have stability advantages over just the resistor? But might be overkill? I do have a single pcb for a JLM 99mb which seems like a fun design to build too but I really wanted to come up something from scratch. I’ve been reading into amek stuff, RN TLAs, cohen stuff, Jim Williams trans amp mods on soundcrafts, I’ve also been looking at that one portico 511 thread on here and that looks cool too but I don’t want to dish out for more transformers and attempt red silk. I think I’ll stick with impedance balanced for the output but I am also interested in THAT 1646 output if it ends up needing it. I havent started on a schematic quite yet. Would love any answers and suggestions. Ope forgot to mention these will be run on +/- 15Vdc.
So yeah I guess my brain is telling me since the transformers are small and probably bandwidth limited. (I think they came from a teac/tascam mixer.) That if I could blending it with a clean extended bandwidth front end might give me at least a blendable HPF and LPF at the front end. Maybe if lucky some vibeyness?
So yeah I guess my brain is telling me since the transformers are small and probably bandwidth limited. (I think they came from a teac/tascam mixer.) That if I could blending it with a clean extended bandwidth front end might give me at least a blendable HPF and LPF at the front end. Maybe if lucky some vibeyness?
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