Sure, my question being......there are mix matched outputs.
There are IRF530 and IRF9530 "N" and non "N" versions. Do you happen to know which version these amps used?
I will definitely take a copy of that schematic if you would be so kind to send it to seankane89@hotmail.com
Thanks again so much.
There are IRF530 and IRF9530 "N" and non "N" versions. Do you happen to know which version these amps used?
I will definitely take a copy of that schematic if you would be so kind to send it to seankane89@hotmail.com
Thanks again so much.
DONT mixed. try them either the old or newer version, newer are 'Ns' but be sure they are belong the same batch number and mfg date.
I upgraded these with out issue to 540 and 9540 way back in the later 90's and early 00. use 540 and 9540 they should drop right in with just minor bias checking. N has noting much to do with these amps, only Rockford Fosgate's I think... Think I still own a couple of these Alpines with those upgrades in them, gotta look around in the shed sometime lol...Just slightly beefier current handling when you update these....
Should I leave the gate resistors as they are or do I need to use a different value when upgrading to the 540/9540? I stock a lot of those as most of my work is on older Rockford amps.
Another question being about the bias settings and the other pot(s) in the power supply. I don't have test point marks or know what the voltages are suppose to be set at without a schematic. Do you have any suggestions as a good reference point?
All these old school Japanese amps measure DC milli-volts drop across the big resistors tied to each output set, in the case drain or source resistors. There should be some test points near by even on these amps. I don't have the schematic handy but I am sure they are there somewhere near by.
Gate resistors should not need to be changed, I never did and never saw any errant heat and gate drive issues on the ones I did...hope this helps some...🙂
Oh as for bias voltage, something between 2 and 5 mvdc should do nicely, the higher you go the more you have to test with heat to make sure it does not thermal run-away. So be wise aboit adding bias, as too much is too tight or two pieces lol....
I uploaded a soundstream test page, its just a go here kind of thing for where the test points should be on any Class AB type amp, even this Mosfet amp should have similar resistors and so similar test points...😉
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