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Mc2300 fans

I feel like the fourth one is getting warm because of the fact its the center one and the hot transistor on the board is directly in line with it . The fans come on and draw even more heat across it maybe . Interesting. This part is all new to me as i said I am not a tech ,what so ever . This is a fun hobby .
My day job I have a construction company with caterpillars.
 
Be very careful where you put your finger when the unit is on......there are DC voltages in this amp that will stop your heart or start it back up if needed.

Heat will be generated when the amp is driving a load, typically will get its hottest at 1/3 output.

I realize the amp has been performing for you.....but I see bailing wire and duct tape holding it together......

I would also check the other amps.
 
This is the first time I’ve opened this one. I find it all fascinating . Been running it with the lid off and the fourth heat sink doesnt have an alarming amount of heat anymore . Its warm but the transistors seem as normal as the others. I will get a lazer from the service truck next tuesday and see if i can point at odds n ends to see temps . Those tip 41c buggers sure throw the btus though. Hard to touch for any length of time. And no I’m very cautious about death voltages that lurk within. I’m a tad paranoid even after its unplugged.
 
I hope members who read this post in the future will follow well known personal safety considerations.......

This is another obvious reason that prospective purchasers of these units take a careful look inside. These questionable " get'er done" repairs are most common for units used in commercial applications but there are so many questionable repairs out there.......who knows.

We will see how long before the OP's amp lasts before it finally starts releasing the magic smoke.
 
Was gone over by a supposedly well known guy in toronto as per the ad 3 years ago . Ran like a top since . But now the little pop sound when the fan shuts off . Everything else looks original inside . Be easier to buy new cards than ship the whole amp. Was 500cdn to ship here one way . Rather than sit here like a moron and wait for things to explode i like to at least try and be proactive . Only so much a guy that didnt spend his life staring at a work table can do. Not my field of expertise.
 
Davekayc said:
Was gone over by a supposedly well known guy in toronto as per the ad 3 years ago . Ran like a top since . But now the little pop sound when the fan shuts off . Everything else looks original inside . Be easier to buy new cards than ship the whole amp. Was 500cdn to ship here one way . Rather than sit here like a moron and wait for things to explode i like to at least try and be proactive . Only so much a guy that didnt spend his life staring at a work table can do. Not my field of expertise.
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Did you check to see if the fan still has the disc cap across it? Typically wired right to the fan at the power terminals.
 
Well there she is. I wonder if it's just dried out over the years. It's purpose is to suppress the spike resulting in the collapse of the magnetic field when turning off the fan.
 
Davekayc said:
Was gone over by a supposedly well known guy in toronto as per the ad 3 years ago . Ran like a top since . But now the little pop sound when the fan shuts off . Everything else looks original inside . Be easier to buy new cards than ship the whole amp. Was 500cdn to ship here one way . Rather than sit here like a moron and wait for things to explode i like to at least try and be proactive . Only so much a guy that didnt spend his life staring at a work table can do. Not my field of expertise.
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I am sure someone would marvel at the well known tech's ability to slap together a repair using sub optimal parts, I would be concerned what has been done on each heatsink in a effort to just "get'er done".

I do not believe there are any more new boards available and the ones I have seen on the auction site to be more suspect than yours.

The popping noise might be irritating at the volumes you are cranking the level at but my concern is why is that fan coming on.

Are the fans on the other amps coming on.....does the other mono amp have the same issue when connected to the other sub.

These were the intial questions I suggested you check out first.

You have to start out with the basics.
 
This amp the heat sinks look bone stock. All components appear to match each other. Thats not to say something couldnt be wrong on them.
The other amp performs the same duty identically there are no crossovers in the enclosures , its active mono summed before the amplifiers . The amps are bridged the same and the gain is only set at 10 oclock.
Single rca to one input . Mono switch on. I’m going to take the lid off the others and take a look see .
 
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I feel like this is the first time its ever been open. This is a sequential serial to the other . Fan never comes on at low levels. Whereas the one with issues the fan comes on with very low level music .
 
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The picture posted shows driver boards with the original predrivers. These boards could easily be untouched since new.

The idea behind switching the load on the "popping" amp is to rule out a subwoofer issue causing the amp to heat up more the the other. Sometimes the simplist tests give the most information.

Kind of like checking if there is fuel in the tank and a faulty full reading fuel gauge before you tear apart the fuel injection system.
 
What do you suppose would happen . If A : i switched sides with the cards right for left within the same amp .
B: I swapped cards between amps ?
C: i connected the speaker to only one side or the other of the same amp vs bridged .

If the fourth heatsink is getting warm , which side is that ? Just thinking in terms of isolating an issue .
 
I know when one of your big cats won't start you instantly pull the engine and start tearing it apart.

I assume if you would contact your mechanic he would have you check the fuel, maybe the fuel filter, before you start tearing it down.

You need to check the basics first.

Is the one sub's voice the coil causing one amp to run warmer than the other? By switching subs you can check this.

By then switching the input into each amp you can resolve if something upstream is causing one amp to work harder than the other.

I know these are tedious tests but you have to do the basics first.
 
Switched subs side to side . Same difference . Fan comes on . Used the lazer . At times components measured up to 120f didnt seem alarming compared to the other two amps . Everything mostly hovered around 98. The fourth heatsink would kick the fan on at about 110. All the other heat sinks were less than that. Interestingly the driver boards were reversed left for right , and the fins had all the same characteristics.
The pop sound i discovered isnt coming from the sub . The woofer above it is making the sound when the fan shuts off, the woofer of the 4430 is being powered in stereo by the middle 2300.

Mcintosh c46 > jbl 5234a with 4430 cards >
jbl bx63a sub crossover > passthrough to stereo mc2300 as well as sub out to twin mc2300 bridged.

So now what
 
I am supposing this means caps to do with the input . Has to be something getting out through the indoor ? I will pull the beast out of the rack next, and flip it over .
 
So we are finally back to the begining and have determined it is not the sub amp causing the popping noise even though it has a questionable repair done in it's 50 year old past.

I can not tell from your posting if you have tried switching the LH output to the RH speaker (and Rh to Lh) of the center position stereo acting amp?

You need to determine if the cause is because of a amp issue or a speaker crossover issue. Switching the amp output will help find a answer, especially if the problem switches sides.
 
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