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The man who fell to earth

Amp works well ONLY through AUX 2

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My just purchased (mint condition apparently) 1993 Marantz PM72 distorts badly, or only plays through one channel on all inputs other than AUX 2 which plays fine?

(PHONO, AUX 1, C.D all behave oddly, either cutting out completely or with drastic distortion).

When I select Direct Source even stranger things happen with the balance control not working, solving distortion or moving it to other channel etc... , but not to AUX 2 ???

 

I choose to believe that the lovely seller who travelled an equal distance to me to meet me at the Ferry, new nothing of it's failures, but I am so disappointed.

 

I have taken the lid off and provided a course of Deoxit, but that was wishful thinking.

The only physical defect i see is the south end of the red NEC part (see attachment closeup) that is labelled as a relay??? It is cracked/split and a bit bulgy at one end. Could this be the sole cause? (more wishful thinking).

 

Odd that it works AUX 2 and not any others.

PC151548.JPG

PC151549.JPG

PC151551.JPG

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It's hard to see in the photos, but are the capacitors in the top photo bulging?   They should be flat on top, not curved.  If this is true, then they will need replacing (it is possible that even if they haven't bulged that they could be due for replacing).

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Guest Muon N'

The relays may need replacing, or at the very lest cleaning, this needs a proper look at IMO, possible once the faults are diagnosed a complete recap.

 

What is with the blackening ( burnt look ) in this area?

 

That area and around the relays appear to be hot spots, for want of a better term.

 

PC151549.JPG.4e02abbba58ca7678b10ec5e518c11ea.jpg.047a0f2c17083a134c9dea222850d2eb.jpg

 

Edited by Muon N'

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Guest Muon N'

Also, in direct mode the tone controls and maybe the balance function could be by-passed, would be detailed in the manual.

 

That resistor next to the relay in the first pic looks heat stressed.

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Most probably the selector switch itself, you would need to remove it and pull it apart for a good clean. The balance control is bypassed as well as the tone controls in direct mode.

 

The service manual is here, you will have to join if you have not already:

 

https://www.hifiengine.com/manual_library/marantz/pm-72.shtml

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Guest Muon N'

So the pots and switches haven't been cleaned?

 

My mistake, I read too quick and thought the mention of deoxit meant they were done.

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11 minutes ago, Muon N' said:

So the pots and switches haven't been cleaned?

 

My mistake, I read too quick and thought the mention of deoxit meant they were done.

I think he did that, but as someone once said some of these switches need to be disassembled to clean them, they likened it to trying to wash a car in a garage by putting the hose up against the key hole.

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12 hours ago, The man who fell to earth said:

I choose to believe that the lovely seller who travelled an equal distance to me to meet me at the Ferry, new nothing of it's failures, but I am so disappointed.

You're obviously a nice fellow but.............

 

It's reasonable to presume that a car ride didn't cause these problems have you spoken with the seller how long has it been since you took ownership, did they at least test it before bringing it to you I would think that is a minimum when it comes to selling gear?

 

I'm presuming you paid a fair price thinking it was "mint condition"

 

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Guest Muon N'

I'd return it for a full refund.

 

That was in that condition when he had it before driving over with it, like @BATMAQN states, the car ride would not have caused any faults, so no way anything like mint condition, more faulty for repair or parts.

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I was thinking maybe the 'vibrations' during the ferry ride caused some cold solder to dislodge?

I can't believe he would sell it like this as mint. He as very good with communication and met me at the Ferry.

In the photos the amp is clearly hooked up to Yamaha NS600m speakers and a Marantz C.D player also for sale,  so I presumed it had been played and tested.

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Guest Muon N'

Sorry, none of those things guarantee he was above board, some people are very charming but also sly, con men are experts at presenting 100%

 

But I can understand why you may have trusted him, but it might be one of those occasions where the trust was unknowingly misplaced, I have been down this road also.

 

Edit: @The man who fell to earth was he unwilling to met at his place? and why it was a ferry meet?

Edited by Muon N'

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7 hours ago, Muon N' said:

The relays may need replacing, or at the very lest cleaning, this needs a proper look at IMO, possible once the faults are diagnosed a complete recap.

 

What is with the blackening ( burnt look ) in this area?

 

That area and around the relays appear to be hot spots, for want of a better term.

 

PC151549.JPG.4e02abbba58ca7678b10ec5e518c11ea.jpg.047a0f2c17083a134c9dea222850d2eb.jpg

 

Fortunately that is just a shadow, the photos were taken late last night, I only picked the amp up yesterday arvo. Thanks

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20 minutes ago, The man who fell to earth said:

Fortunately that is just a shadow, the photos were taken late last night, I only picked the amp up yesterday arvo. Thanks

Up to you but I'd be going for a refund as @Muon N' has suggested

Edited by BATMAQN

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bought as is, not tested by buyer, buyer accepted the sale conditions, buyer will need to issue small claim proceedings and PROVE in front of judge and seller (if they bother to turn up) the unit was damaged prior to handover (impossible) and then if gets an order against seller it wont be enforced..

 

next time dont buy before trying (isnt that the advise you will give to others for hifi gear? )

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3 minutes ago, hopefullguy said:

bought as is, not tested by buyer, buyer accepted the sale conditions, buyer will need to issue small claim proceedings and PROVE in front of judge and seller (if they bother to turn up) the unit was damaged prior to handover (impossible) and then if gets an order against seller it wont be enforced..

 

next time dont buy before trying (isnt that the advise you will give to others for hifi gear? )

Yeah that's worst case scenario if the seller proves to be belligerent some well worded polite communication first up may solve the issue, if they are reasonable a positive outcome should be achievable even a part refund.

 

Unless the guy is a straight up con man he should agree to something but if he doesn't then yeah you're screwed this time a lesson we all have to learn at some point unfortunately.

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The 'mint' amp was very dusty, I've just removed the selector switch to clean more thoroughly.

I know I should not have trusted description, my mistake, I don't ant to get confontational, and I haven't told him yet because I'd hate to do so and then clean a switch and it's all good.

I still wonder about the ferry, the vibrations were quite obvious.

Edited by The man who fell to earth

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4 hours ago, HypnoToad said:

Most probably the selector switch itself, you would need to remove it and pull it apart for a good clean. The balance control is bypassed as well as the tone controls in direct mode.

 

The service manual is here, you will have to join if you have not already:

 

https://www.hifiengine.com/manual_library/marantz/pm-72.shtml

 

I took the Selector switch apart as Hynotoad suggested and gave it a better clean and the distortion has gone !!!

Thanks HypnoToad.

I was confused because AUX2 was unaffected.

Glad I didn't complain to the seller straight away, but still he must have known it didn't sound right.

Would that NEC resistor that is obviously split and bulging be effecting the sound?

 

 

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No need for anything confrontational polite reasonable communication is key with any issue that may arise, you owe it to yourself to at least

1. Advise the seller of these issues give them a chance to explain or deny.

2. Let them know you're not satisfied with the item especially considering the mint condition rating.

3. Ask if something can be done to resolve this. 

 

If they are reasonable then they should be willing to do something.

 

A ferry ride wouldn't wreck an amp they are pretty tough beasts.

 

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4 minutes ago, The man who fell to earth said:

 

I took the Selector switch apart as Hynotoad suggested and gave it a better clean and the distortion has gone !!!

Thanks HypnoToad.

I was confused because AUX2 was unaffected.

Glad I didn't complain to the seller straight away, but still he must have known it didn't sound right.

Would that NEC resistor that is obviously split and bulging be effecting the sound?

 

 

Glad you've had a positive outcome 

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1 hour ago, The man who fell to earth said:

I took the Selector switch apart as Hynotoad suggested and gave it a better clean and the distortion has gone !!!

 

Good work, I have one of those pesky Yamaha integrated's and it's the same with those, you can spray from the outside all you like but you need to take them apart to do the job properly, glad it helped.

 

When I lived in the U.S. I met people half way to buy things advertised on Craigslist, and every time there was an issue never mentioned in the ad, luckily I could fix all of them so it didn't bother me, it's par for the course. If you're happy with the price and you fixed it, you took the seller down IMO. 😉

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Guest Muon N'

The ferry trip would not have caused a dirty selector switch, it was in that non 100% working condition when he advertised it as mint. Anyway, glad it is working, 

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Good that it turned out to be a relatively easy fix.

 

The seller may have advertised it in good faith.  The unit, being dusty, had probably not been used in many years which would have given time for the selector switch problems to develop.  The seller's recollection may have been accurate that it worked in "mint" condition last time it was used. 

 

Ultimately it doesn't really matter how it was advertised, you have it working well for minimal cost/effort.  It is unlikely that anything will be achieved by confronting the seller.  Put the difficulties behind you, and enjoy a nice amplifier. 

 

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