the trio i was gonna sell......

wheelieking71 · Post by **wheelieking71** » Tue Nov 17, 2009 8:03 pm

well, i got the amps tonight! pretty stoked. i have always liked the M-series. they are just a little worse for wear than i had hoped. they arent bad at all considering thier age. and they all work! each one spent about 10 mins in the truck (a little longer for the M-44 to check all 4 channels). so far, only one major issue. the gain pot on the M-25 is siezed up tight. a little moisture=a little rust and, knob no spinny no more. it may break free with a good twist, but im not gonna try. started with the little guy and i am in the midst of dissmantle! only thing to note besides the siezed pot is the sheath on one cap sliding down. okay, time for caps. thats to be expected. pics:

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i looked the board over real close, and i dont see anything obvious. im no amp tech, but i have looked at all the "what to look for pics" on here. definately potential to once again be a great little amp. so in light of there being a couple little issues. rather than sell them off right away, i thing i am going to start me a little project. "M-series restification"!! dont know how indepth it will get yet. gotta scrutinize the other 2 and come up with a game plan.

wheelieking71 · Post by **wheelieking71** » Tue Nov 17, 2009 9:17 pm

M-44 was next in line. no major issues. looks like someone has been here before. again time for caps:

not sure if it shows up in the pic, but there is quite a bit of residue on the trace just to the right of the caps in this pic. leaky-leaky:

and these 2 little guys arent doing so well (as per one of the awsome threads on here taught me to look for):

so far pretty much what i expected. one more.

Pillow · Post by **Pillow** » Tue Nov 17, 2009 10:29 pm

Looks good!!! Holding out on the M100 are you

I have to do the same cap swap for my M25 and M50 as well. The M50 are starting to leak, but the M25 looks good... All caps will get changed for good measure.

Keep the pics coming!

wheelieking71 · Post by **wheelieking71** » Tue Nov 17, 2009 10:52 pm

M-100 right here!

again, the little dudes next to the big bad resistors are dropping thier drawers LOL

and again, residue on the board next to these guys:

HoseHead · Post by **HoseHead** » Wed Nov 18, 2009 5:35 am

They are works of art, really.

Polyester carpets (static electricity) and integrated circuits generally don't live well together....

HH

wheelieking71 · Post by **wheelieking71** » Wed Nov 18, 2009 6:32 am

crap! thanks for the tip. time to take them to the garage.

Post by **kg1961** » Wed Nov 18, 2009 6:40 am

have the caps ever been changed?

wheelieking71 · Post by **wheelieking71** » Wed Nov 18, 2009 5:21 pm

not sure where your talking about. but, unlike i was told somebody has definately been here before.

Post by **kg1961** » Thu Nov 19, 2009 7:32 am

best of luck with the sale

Post by **mhyde71** » Thu Nov 19, 2009 9:10 am

i actually think it might be OEM in fact,
my 44 is same way- think it was like an after thought at factory or realized not enough room--- at least if it is what I think it is that I am seeing/looking at- B/C Mine is/has same configuration there- silicon holding them in place and on top of something else-
not at my board right now, but will/can confirm later today- and see if mine is same where youre talking about

Post by **kg1961** » Thu Nov 19, 2009 9:25 am

sorry if im wrong it just doesn't look like the other items solider on the board
just looked at some more pics on the web its look OEM

Post by **mhyde71** » Thu Nov 19, 2009 9:40 am

also
and not sure if you already mentioned or noticed...
but just the same on my 44- the smaller caps are also exhibiting / indicating being exposed to extreme ot long periods of heat ...

Therefore I am replacing those smaller caps and the resistors that are the origin of the heat / culprit(s).

yellow circles indicate the two resistors that I am replacing and the blue circles indicate the caps I will be doing
should be 5 caps all together (at least on mine I found 5 that need/shoudl be replaced.

AND as it has been discussed in other threads previously- the resistors can be "upped" in ratings- believe yours should be like 90/91 ohms maybe 2watts...
eric just has been workign with me and said like a 150ohm and 3 or 5 w would be good.
i will be ordering some ofthose replacemet parts- so if you need or want- JLMK

matt

wheelieking71 · Post by **wheelieking71** » Thu Nov 19, 2009 11:46 am

ya, i have read all i can find so far on these Ms on this board. good reading and info for sure!! lots of very accurate and pertinate info (its a shame "1moreamp") doesnt frequent anymore. hes an ace for sure! (dealt with him before on a different brand and he was awsome). i do plan on replacing everything i can think of! bring these guys back up to spec. for another 15 years. not sure what i will do with them when im done, but they deserve restification!

wheelieking71 · Post by **wheelieking71** » Sat Nov 21, 2009 9:57 pm

got started today, started with the little guy. pulled the caps, and looked it over real good. taking inventory of what i need to order. here is the top of the board after pulling the caps:

and the bottom:

and here is my biggest issue, corroded gain pot:

Misfire · Post by **Misfire** » Sun Nov 22, 2009 12:20 am

Great start! The M series are wonderful amps! I have a bandit running the MB Quart 6.5 set in my Bronco.... sounds so good! Keep the pictures coming!

wheelieking71 · Post by **wheelieking71** » Sun Nov 22, 2009 9:13 am

i spent hours lookin last night, and i found thousands of gain pots, but i dont know what im looking at. does anybody, maybe, have a part# that will work? that would be so ohh-very awsome!

Post by **mhyde71** » Sun Nov 22, 2009 9:51 am

the footprint and pin out is going to be the most important aspect to consider.

have you tried here:

http://vimex.com/

i know they USED to supply to PG back in day, whether or not they have the pot or not I dont know... but PG used these guys until the original PG buyer left and was replaced with new guy that started sourcing from Taiwan

I ALSO KNOW that they have allot more than what they show on line.
best thing to do is send them a pic or two of the pot with the footprint dimensions, and see if they have or can get for you.

m

wheelieking71 · Post by **wheelieking71** » Sun Nov 22, 2009 11:57 am

well, i found this at MOUSER.COM:
http://mouser.com/Search/include/LargeP ... 110077.jpg

this looks to be the same case, and mounting. but, how do i know the specs i am looking for? stamped on the side is "alps". obviously the maufacturer. and stamped on top is "LT-50-3C". i have no clue what that means, and i havnt been able to come up with anything in any kind of search. (but im trying!)

Post by **mhyde71** » Sun Nov 22, 2009 1:48 pm

"Linear" something & 50K (ohm), something something I bet