This is my third Pass DIY project - A60 monoblock. 1. Monoblock approach. 2. Heatsink size is 230mm x 280mm x 62mm (WxHxD). 3 pcs for each channel. Maximum temperature on heatsink is less than 45 deg C (room temp 25 deg C). 3. Power transformer is from UK Airlink 625VA 25V x 2. 4. Capacitors are 4 pieces 33,000uF 63V for each channel. 5. Mosfets are IRFP240 x 12, IRF9610 x 3 for each channel from IR. Transistors use BC550C. 6. DC offset at output for both channel about 42mV with top cover closed, 32mv with top cover removed. 7. When input resistor use 10k to ground, the base is weaker, later changed back to 68k to ground. 8. Add one cap 560pf from collector of Q4 to output, similar to Amplifier series amp to improve stability. High frequency is relatively lower. Best regards, Spencer Cheung, .(JavaScript must be enabled to view this email address)
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