hi all im am new to the forum and need some advice with my nad 701 amp, i bought it two weeks ago and it worked fine when all plugged in, i turned it back on 2 days later and very low distorted sound and it switched into a protection mode, i have had a read around and replaced the four big metal transistors mj2955 & 2n3055 and acouple of others b649a &d669a as they were getting hot and its still the same but now the sound is louder but still distorted and the amp now stays on, do i need to add the resistors which people say to do in a thread on here and could someone please say what resistors i need and where to solder them thanks for any help, also does this amp have mute transistors and how can I locate them to test thanks in advance
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yes i have the shematic 701 i found it on here, i have used it to order exact replacement parts, im still waiting for some transistors to get here before i can go any further, up to now i have changed all the .1uf caps 180ohm resistors 100ohm resistors mj2955 & 2n3055 and still need to change 4amp fuses, can i replace the 6800 caps with 10,000 to improve sound ?, thanks for your reply
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Hi sorry, all but one fuse is blown, after testing transistors q415,q417,q418,q416,q411,q409q413 (split in two) q414,q410,q412, q407 and 408 around half was damaged, resistor 453 was fried other resistors seem ok ? Tested loads out of circuit, l am just waiting for some parts to arrive then I will change them, thanks for the replies
I no what the symbols mean, diode capacitor ect my problem is the actual board layout is so different I get lost with it so I have been ordering parts and changing them, all the .1uf caps are swollen so I've changed them along with a few other bits for now, so till I have them all I'm stuck, thanks for your reply
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