Maxon CP9+ Pro power problem

chokeslam512 · #1 08-22-2011, 06:38 PM

Okay, this is a bit strange but maybe a common thing. I got a Maxon comp not too long ago from another TBer. It worked fine on my pedal board with a VDL PP2+. I changed boards, and then it didn't work. The small "clip" LED would come on when it was powered up, but once the foot switch was engaged, the "on" LED would not illuminate.

Fast forward to practice Sunday, powered up the board and the Maxon turned on and operated as it should.

Today, I plugged in my board and nothing from the Maxon, same situation as described first. Only this time, I left my bass unplugged... when I touch the end of the cable going into the comp, the clip light lights up as if it was compressing the signal but the operating light is not on when all this is going on. I tried a one spot with the comp and it is doing the same thing. Anyone have a solution for this? I have a gig Saturday and would really like to use this thing but it is a little iffy.

HALPMEPLEEZE!

chokeslam512 · #2 08-22-2011, 06:55 PM

Okay, this is weird, I plugged it in to another wall outlet and it seems fine now. Never mind. I think I'm going with the MXR instead so I don't have my emotions hurt like this again.

boomertech · #3 08-22-2011, 07:17 PM

I think the CP9+ uses a charge pump for its internal power. I have seen many charge pumps fail in a similar manner. Most of the failures were from the older pump chips that do not have the over voltage protection that many of the newer chips have. Over time, some of the older chips would also start to latch up and not oscillate until it was powered cycled a few times. Sometimes another part of the circuit is failing and requiring more current on start-up and the pump chip will sometimes latch.

I don’t know for sure if this is the case with your pedal, but the symptoms you describe are similar to what I have seen. If it is the pump that is defective then the only remedy would be to replace the faulty pump chip and possibly the charge capacitors. Most of the newer charge pump chips are much more robust than their older brothers.

-Frank

king_biscuit · #4 08-22-2011, 07:21 PM

Didn't you just pick this up in the TB classifieds a few weeks ago? I'd contact the seller about this.

chokeslam512 · #5 08-22-2011, 07:42 PM

Quote:

Originally Posted by king_biscuit

Didn't you just pick this up in the TB classifieds a few weeks ago? I'd contact the seller about this.

Yes I did but it did work at first so I don't know if I have any recourse.

king_biscuit · #6 08-22-2011, 07:55 PM

Quote:

Originally Posted by chokeslam512

Yes I did but it did work at first so I don't know if I have any recourse.

It sounds like the problem is intermittent. Maybe you just didn't notice it at first.

chokeslam512 · #7 08-22-2011, 08:04 PM

Quote:

Originally Posted by king_biscuit

It sounds like the problem is intermittent. Maybe you just didn't notice it at first.

Yeah probably. I plugged it in to a one spot two different times since the genesis of this thread and it worked both times. The seller said he had no issues with it.

king_biscuit · #8 08-22-2011, 08:06 PM

That's supposed to be a really great pedal, I wonder if Maxon could repair it at a reasonable price? Might be worth checking.

bongomania · #9 08-22-2011, 09:05 PM

Quote:

Originally Posted by boomertech

I have seen many charge pumps fail in a similar manner. Most of the failures were from the older pump chips that do not have the over voltage protection that many of the newer chips have.

Yep, that matches my experience too.