Hi All,
I've just finished my late project, building Crescendo Millennium amp and I run to a problem with Bias. Namely, I cant reduce bias setting to the desired value. Bias is twice higher than it suppose to be. Between TP3 and TP2 I measure 0.1V instead of 0.05V. I assume that one of the fet transistors is oscillating. Can anybody advice on this? Thank you a lot!
I've just finished my late project, building Crescendo Millennium amp and I run to a problem with Bias. Namely, I cant reduce bias setting to the desired value. Bias is twice higher than it suppose to be. Between TP3 and TP2 I measure 0.1V instead of 0.05V. I assume that one of the fet transistors is oscillating. Can anybody advice on this? Thank you a lot!
I've build the Crescendo ME about 8years ago and used self made PCB and had connected the output devices with 4inch wires to the pcb. placing the gate stoppers R32 +R33 directly to the gate of the FET stopped the oscillation.
I've noticed I've giving you wrong advise regarding the bias spreader output voltage! I read your bias current is to high (0.1V/0.22R = 0.45A). You have to lower the bias spreader output voltage!
You have to increase R28, try 560R. There is almost no risc involved, the higher R28, the lower the bias current throught the output fets.
Search for bais spreader of vbe multiplier (Vgs multiplier if Fet) for more details.
I've noticed I've giving you wrong advise regarding the bias spreader output voltage! I read your bias current is to high (0.1V/0.22R = 0.45A). You have to lower the bias spreader output voltage!
You have to increase R28, try 560R. There is almost no risc involved, the higher R28, the lower the bias current throught the output fets.
Search for bais spreader of vbe multiplier (Vgs multiplier if Fet) for more details.
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