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QSXM2 Input Transistor Biasing

Started by MattB94, October 05, 2023, 02:51:41 AM

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Hi Per-Anders (and to anyone here who can answer this question),

First, just want to say thank you for all your good work designing all these things and making them available to us DIYers. On to the question...

I am planning on building a QSXM2 phono preamp, and I hope to optimize it for my Sumiko Blue Point No.3 MC cartridge. It has a fairly low output impedance, 28 ohms. I hope to bias the input transistors of the QSXM2 (so, T5-T12 and T17-T24) to 1mA, at least. Do I need to change anything? Presumably, I would alter the value of R16-R23 to something other than 15kohms. Should I change these resistors? Or something else?

Thank you for your help with this!
Should be building DIY projects instead of procrastinating...