Mtx 1501d

[klzemazda]

hey guys!Ive had a problems before, with my mtx 1501d(burn powersupply).Ive replace the 8 power transistors(Fet 436-441) and the to resistors(r436 r435),that was bad!Now the amp turns on,an it plays,but the power supply is making a high pitch noise.Also Led 238&399 are on also.The only reason i think it plays is because the owner before me mod this amplifier!Do anybody have any ideas as to why this is happening !!Also,before it stop working,the power supply whould make noise when i first turn it on,then it would go away.I also notice the yellow caps looks funny.( in the power supply area,in front of the FET transistors)one of them looks like it was leaking before.thanks

[Perry Babin]

The power supplies in these amps can be very noisy.

Does the heatsink under the power supply FETs get hot quickly when you drive the amp hard?

Most of the yellow caps are film caps and therefore can't leak. If the case isn't melted on the film caps, the substance you see on the board is likely from something else. I'm assuming that you're referring to the film caps because I've never seen a 1501 with yellow electrolytic caps.

[klzemazda]

Originally Posted by Perry Babin

The power supplies in these amps can be very noisy.

Does the heatsink under the power supply FETs get hot quickly when you drive the amp hard?

Most of the yellow caps are film caps and therefore can't leak. If the case isn't melted on the film caps, the substance you see on the board is likely from something else. I'm assuming that you're referring to the film caps because I've never seen a 1501 with yellow electrolytic caps.

Yes,the yellow film caps..I guess the stuff on the board came from the caps i change before.What about the LED lights (238&399).Are they suppose to be on???

[klzemazda]

Played it for like 10 mins.It didn't get hot At all,just that the power supply was noisy!

[Perry Babin]

LED 463 should be lit when remote voltage is applied.

LED238 should be lit after the initial mute delay.

LED399 (between the large caps?) will be lit when the large capacitors are charged.

[klzemazda]

Thanks For the Info

[klzemazda]

One more question.I cant remember which way the button inside the amp should be??In or out?The button for 18v input.

[Perry Babin]

I know of no '18v' button. Is this mentioned in the owner's manual? If so, email me a copy or the text associated with it.

[Cr@sh]

This may be modded, I remember talk of this amp when it came out of people modding them. I just googled and found a bunch of pages of people doing this for this particular amp.

[klzemazda]

I talk to a mtx tech today.That button is a safety protection bypass button.Use in car audio competition,so you may double stack amps,run lower ohms output,and run a higher input voltage!In normal use,this button should be in the out position