Alpine mrv-f300 works fine for 10 min and then audio gets bad

Power supply issues maybe ???? at least that's what it sounds like with all 4 channels being effected evenly their only common thing is the power supply. perhaps its going into fault and not shutting down and or muting the channels, this would explain the unique symptoms.... Perhaps bad solder joints, thermally intermittent devices in the lower 16 volt regulators. Just sounding some ideas...:)
 

ivkata

Member
2010-12-03 2:37 am
i cant really do that now the amp have desided to play only bad.bad bad bad gate voltage is 0.8 no wonder why shitty audio comes out

kia 494 shows this

Pin 1: 1
Pin 2: 1
Pin 3: 3.8
Pin 4: 0
Pin 5: 1.7
Pin 6: 4
Pin 7: 0
Pin 8: 15
Pin 9: 0.8
Pin 10: 0.8
Pin 11: 15
Pin 12: 15
Pin 13: 5
Pin 14: 5.6
Pin 15: 5.3
Pin 16: 0.00
 

lukej2000

Member
2012-11-01 3:06 am
I got this amp here Alpine mrv-f300 its a 4 chanell v12 amp.will work fine for 10 min all audio chanels sound great and then distortion and gets worse ans worse.All chanels go bad at the same time ,any info is apresiated

I have the same amp - Alpine MRV-F300 and I have same problem. It runs perfectly and very loud for 10 minutes, then it starts buzzing and the output drops (gets quieter).

This affects all channels, in bridged mode and unbridged.

What could this be?
 
10 minute problem

Hello,

Had similar problem on a Clarian unit but only with one channel. Unit would work fine for just over ten minutes and then would start distorting badly.

Opened up unit, checked tightness of heat sink screws, put fresh silicon grease on power chips/heat sink. Touched up solder joints going to the main power amp chip, put things back and has worked fine since.

Believe the solder they are using now (no lead) is not as strong and the solder joints can crack / break. As things heat up, expansion causes the contact to get worse and the result sounds like ****. Car stereos do get quite a bit of vibration and shock.

Personally I am using silver solder which is harder and take a little more heat to melt, but is stronger.

For whatever it is worth, fairly easy to try.

Regards,
Greg