Discrete All-Transistor RIAA-Equalized MM Phono Preamplifier 2.

[@jim9930]

Looks like ~2nv/rt Hz or the equivalent noise of 200 ohm resistor. Perfect transistor matching with five 1845's should be around 1.4nv (3dB better or ~150r). ie The two quietest ones are doing all the heavy lifting, higher Hfe, lower Vbe.
Nice project! It would be interesting to try MPSA06 or 2N4403 (PNP)...
Also, your at the equivalent noise of two paralleled LM4562's 👍 {below vinyl surface noise}

[@buildaudioamps]

Thanks!

[@robertkovar8710]

switching DC-DC XL6009 (400kHz) for phono is act of brutality, :) you need low noise power supply - linear (capacitive multiplier or shunt )

[@buildaudioamps]

Please refer to the schematic diagram. Test results showed otherwise. Thanks.

[@joancarlescanadas5123]

Totalmente de acuerdo; es un circuito elevador de tensión que, usa señal de conmutación y produce ruido ; se deben usar una power supply convencional con transformador separador, estabilitzador y filtros bobinados o bancos de baterias de 1,5V en serie, hasta obtener los 32V de trabajo. Piensenlo!

[@robertkovar8710]

for maximalist LT3042, preregulation LM317

[@saanjayray]

Nice one

[@buildaudioamps]

Thanks