There is pcb for MM22 in this thread and you must add MC4 for MC input if you need it.
apex fx8 mod bimo (I modified the pcb layout to fit my need). not yet singing, still waiting for the transformer and power supply pcb. Thank you very much Mr. Mile, Mr. Prasi, Pak Bimo/Anis and others for sharing great works in this forum. will update the progress soon 🙂
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Thank you ypaudio for posting your build progress. All the best for your build!🙂
Looking forward to your build and listening experience. Nice compact build..🙂
regards
Prasi
P.S. I have pair of PCBs donated by Ivanlukic.. I plan to start building this amp at the earliest opportunity.
I would recommend higher gain for FX8 (45-50 V/V). That way preamplifier is not needed and the sound is excellent with modern digital sources. One only need input selector and 10-20k pot at the input for the complete integrated amplifier. I use combination of 22k/470R for the feedback and gain setting resistor.
No.
Inrush current is about incoming current into the power transformer when you switch on. This requires a separate circuit.
Overload protection is protection for the output transistors from large DC offset / error voltage or excess output current due to low impedance load etc.
Split it, comand board put on front panel and relay bord on back. You need olny 5 wire to connect this two boards. If you put everything on one pcb you need 13 wires for pot and leds.
please do a measurement of bias from cold up to warm heatsinks, when you get to that point...
Power supply from same transformer or two separate transformers, if 2 supply from one transformer(24-0-24, 42-0-42) +-30,+-60, what is VA of transformer
Regard
Gurpreet Singh (Gsturna)
So i built FH9 (xrk mod) and it sounds beautiful but i could hear hum and some noise when i switch from my trafo with f6 filter to smps+boost board+cap mx+crc , no matter what i did i could not get rid of the noise until i use input isolating transformers, since the isolating transformers weaken the signal i start using preamp, long story short i was trying different preamps and one of them was xrk PCA that i read it sounds good as a preamp, and it really does sounds fantastic i strongly suggest it , very dynamic very detailed and good balance and separation, it was fantastic , but the wired part is i removed the isolation transformers just out of curiosity and boom there where no noise whatsoever , like no audible noise at all, and it is more weird since i m running the PCA with smps+cap mx+crc setup.
anyhow just thought it can be helpful to someone and also maybe someone can explain what is happening.
A.
anyhow just thought it can be helpful to someone and also maybe someone can explain what is happening.
A.
so, bias was stabilised after cca 30 min... was set 50mA.... when is heat sink cold, it started on 80mA, and then is slowly decreasing back on 50mA...
You must use preamp or bufer after volume pot with any amplifier, low preamp (bufer) output impedance virtualy short amp input to the gnd for any volume pot position (volume level). If you use only volume pot input is short to the gnd only in minimum position, with any other volume level input is open.
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