thor.zmt
Well-known member
The Threshold voltage of 1.7V is a datasheet value. My BSS84 Model seems to indicate 2V Vgsth.
Especially for the Guru, a sim with all DC voltages and currents probed and spelled out:
Incidentally, I made up an A-Weight + 5th order 20khz lowpass network (all passive, VCVS & Ohm level resistance's) which suggests an 89dB(A) SNR @ 94dB SPL (or 5dB(A) SPL Self Noise), which is pretty Horrorshow in my books, except capsule noise scotches this big time.
HD @ 94dB SPL & 1kHz at 0.006% (or -83dB of pure H2) is also pretty pukka, innit?
Again, the goal was/is to reuse all of the BM-800 China Mike (except the saddle & Capsule where we go 26mm or 34mm Electret or 32/34mm LDC) including the PCB, mostly use commodity SMD Parts that fit the PCB.
And to make a studio recording Mic that betters relatively affordable (sub 500 USD) China made "recording microphones".
Not to make some supa dupa world record setting something. I leave that to Guru's.
I'm too pragmatic to be a guru.
I will show in a separate the thread the LDC Capsule version, with Bias from P48. It looks....
Thor
