Marantz 2600 Refurb Thread
- Thread starter rBuckner
- Start date
The 2500 probably began as a TOTL proof of concept, but was pushed into existence IMO by the Pioneer SX1280/1980 and the receiver wars. The addition of the Marantz scope and the use of a forced air cooling tunnel were unique (as well as weight saving). Too bad they only lasted for a few years.
Denten
Addicted Member
The 2500 and 2385 were out a year before the SX1980, and SX1280 so I would say, IMO, the SX1980 and SX1280 were pushed into existence in 1978 to one-up Marantz. The 2500 was made for two years 1977 and 1978, the 2600 came out in 1978, the same year as the SX1980. Was the 2600 a knee jerk reaction to the SX1980? did they rush to one-up Pioneer with in the same model year?? Edit: The SX1980 was out BEFORE the 2600 in 1978, I knows this because the SX1980 was the most powerful when it came out, it was short lived though, because the 2600 came out later that same year. It looks like Randy's suspicion that they were rush to market, may very well be true for the 2600 anyway.
I sure wish the original designers where AK members, that would be awesome, wouldn't that be an interesting conversation? I wonder who they are and were they are now?
Sorry Randy I don't mean to hijack your thread.
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AK member Hadrian333 is Tom Ishimoto, who was Marantz's Service Manager in the late 70's and helped to design a number of the big discrete Marantz SS amps, which may have preceded or contemporary to the 2500/2600 lines. I'll PM him to have a look at this thread and this related topic of genesis of the 2500/2600 and see what he may have offer.
I'm enjoying the side trip very much - no apologies friends!! I'm stuck at work on a Monday morning so it's a pleasant distraction.
I plopped the amp module into the chassis and have it all plugged in and now screwed down and the new fan installed. I have a bracket to clean up that mounts the little speaker relay board and then I can - GULP - bring it up slowly on the variac/DBT/voltage & current meter unit. Then it's on to cleaning up the scope parts, then reinstalling the scope board. It will be nice to get to the dial cleaning and relighting work and getting this workout device done.
I plopped the amp module into the chassis and have it all plugged in and now screwed down and the new fan installed. I have a bracket to clean up that mounts the little speaker relay board and then I can - GULP - bring it up slowly on the variac/DBT/voltage & current meter unit. Then it's on to cleaning up the scope parts, then reinstalling the scope board. It will be nice to get to the dial cleaning and relighting work and getting this workout device done.
Denten
Addicted Member
I'm enjoying the side trip very much - no apologies friends!! I'm stuck at work on a Monday morning so it's a pleasant distraction.
I plopped the amp module into the chassis and have it all plugged in and now screwed down and the new fan installed. I have a bracket to clean up that mounts the little speaker relay board and then I can - GULP - bring it up slowly on the variac/DBT/voltage & current meter unit. Then it's on to cleaning up the scope parts, then reinstalling the scope board. It will be nice to get to the dial cleaning and relighting work and getting this workout device done.
Don't you find it hard to put your heart and soul into something like this, and then let it go? I know I would, even though you don't own it, it is still your baby! Like selling a puppy.
I am very much enjoying this thread Randy, I look forward to your first 2385, cheers brother!That would be awesome mech986! lets not forget the 2385 now!
Maybe if Hadrian333 didn't work on the BIG 3 project, he will know who did! 
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wildwill532
Active Member
I asked tmz2 for a new faceplate...no luck 
Denten
Addicted Member
I asked tmz2 for a new faceplate...no luck
She is beautiful just the way she is.
You are a lucky guy for sure.
Here's the saga of the amp module...
The halves are reunited and it's ready to go in.
It has been gently lowered in and push on wire connections remade.
Looking back in from the fan hole.
I scraped and cleaned off the old foam from the fan gasket. It took Goo Gone, elbow grease and some scraping with an X-Acto knife. It was then washed twice to make sure the oily Goo Gone was off. I used 3/8" wide by 3/16" thick weatherstrip from a homey store.
Two of the fan brackets went right back in and another just required minor filing of a rib on the fan but by the power connections I had to do an extensive grind job.
Someone had burned the fan wiring insulation back a bit - the sucker beat me to it! I added some heatshrink to rebuild the insulation. Sorry it's a bit out of focus.
This is where I stopped Sunday evening, just needing to clean the speaker protection relay board's bracket.
The bracket was cleaned after work Monday eve and the board reinstalled.
SO after dinner it was time to test it out so I brought up the power slowly with a variac and DBT. Uh oh, something is wrong!! I poked around a bit while going back to the living room to catch bits of the Grammy's. After isolating it to one side by pulling the two power wires, I hooked up a scope to see what the power supply rails did as the AC mains voltage was coming up and both topped out at about a volt - like a diode or so was connected to ground or some output transistors were swapped NPN for PNP. It was the latter... oops! So I had to unwire pull it all back out and apart to swap the two erroneous ones. Putting it all back together it worked fine. So even experienced techs make mistakes!
The halves are reunited and it's ready to go in.
It has been gently lowered in and push on wire connections remade.
Looking back in from the fan hole.
I scraped and cleaned off the old foam from the fan gasket. It took Goo Gone, elbow grease and some scraping with an X-Acto knife. It was then washed twice to make sure the oily Goo Gone was off. I used 3/8" wide by 3/16" thick weatherstrip from a homey store.
Two of the fan brackets went right back in and another just required minor filing of a rib on the fan but by the power connections I had to do an extensive grind job.
Someone had burned the fan wiring insulation back a bit - the sucker beat me to it! I added some heatshrink to rebuild the insulation. Sorry it's a bit out of focus.
This is where I stopped Sunday evening, just needing to clean the speaker protection relay board's bracket.
The bracket was cleaned after work Monday eve and the board reinstalled.
SO after dinner it was time to test it out so I brought up the power slowly with a variac and DBT. Uh oh, something is wrong!! I poked around a bit while going back to the living room to catch bits of the Grammy's. After isolating it to one side by pulling the two power wires, I hooked up a scope to see what the power supply rails did as the AC mains voltage was coming up and both topped out at about a volt - like a diode or so was connected to ground or some output transistors were swapped NPN for PNP. It was the latter... oops! So I had to unwire pull it all back out and apart to swap the two erroneous ones. Putting it all back together it worked fine. So even experienced techs make mistakes!
it appears that the 2385's front chassis plate indeed started life as a 2500 plate.
I asked tmz2 for a new faceplate...no luck
She is beautiful just the way she is.
True dat, but here's a look at how it could be, click on each image for the full effect!! And yes, these are the Euro Black version I believe. Funny how the lettering looks slightly off white / eggshell-ish color, probably just the lighting. It would pop though with a pure white lettering, or even better with a laser etched silver aluminum showing through.
wildwill532
Active Member
If I'm not getting a new face then that means neither is anyone else for a 2600. They do look nice, I don't even care about the color a new silver one would be just fine.
It would have been nice to get a new face plate but I understand why they aren't made. There were only so many 2600's ever made, like 600 or so maybe, so the demand is low. There's some fixed costs in getting the artwork made, tooling charges and small run metal work and lasering / silkcreening. Tony / TMZ was a fine fellow to ever offer any up from the ones he made for his own pristine collection. I considered a service to us all. He's a heck of a nice guy as well.
Most of the evening was spoken for but I thought I'd plug in the scope amp board. First I thought I'd regrease the TO-220 transistors where they attach to a small "U" shaped heatsink. The first plastic/nylon screw went -snap- and the head broke off. Well ain't that just special! The second one came out fine. Ironically there was never any thermal grease there, just a mica insulator. So there wasn't that much heat and perhaps even they just wanted the two transistors to be at the same temperature. I've had a number of hardware items I've been adding to a list for McMaster Carr so I found some new screws and put in my order tonight.
I know tomorrow night's a goner already and I have cleaning chores elsewhere on the 2600 so I will get those done while waiting on parts. I have to put in a Mouser order soon too as I need a new chassis ground binding post. The screw that is in there has a broken off screwdriver in the phillips slot and is stripped. The new one is a lot like the one on the earlier receivers and is much more substantial and nickel plated to boot.
I also need to mail the owner about the main filter caps and the front panel indicator LEDs for color choice. So I'm off to do that and maybe get a few scope parts cleaned up. Tally ho!!
Most of the evening was spoken for but I thought I'd plug in the scope amp board. First I thought I'd regrease the TO-220 transistors where they attach to a small "U" shaped heatsink. The first plastic/nylon screw went -snap- and the head broke off. Well ain't that just special! The second one came out fine. Ironically there was never any thermal grease there, just a mica insulator. So there wasn't that much heat and perhaps even they just wanted the two transistors to be at the same temperature. I've had a number of hardware items I've been adding to a list for McMaster Carr so I found some new screws and put in my order tonight.
I know tomorrow night's a goner already and I have cleaning chores elsewhere on the 2600 so I will get those done while waiting on parts. I have to put in a Mouser order soon too as I need a new chassis ground binding post. The screw that is in there has a broken off screwdriver in the phillips slot and is stripped. The new one is a lot like the one on the earlier receivers and is much more substantial and nickel plated to boot.
I also need to mail the owner about the main filter caps and the front panel indicator LEDs for color choice. So I'm off to do that and maybe get a few scope parts cleaned up. Tally ho!!
Apparently, the 2385/2500/2600 were done before Tom was at Marantz, but he commented on the fact that forced air cooling had advantages and disadvantages, namely the fan, fan noise, and reliability. The original fans were low RPM so lasted longer, but important to check fan operation from time to time, and bearing can get noisy. Your new fan should fit the bill admirably.
Thanks for checking with him Bart. I agree and add the dust it pulls in makes for an epic cleaning task. The bearing in this one was indeed a knockin' and again I think kindly of Tom/catrafter for suggesting it was a good idea and what the part number was.
My new plastic screwsies are to be delivered tomorrow so I can get the scope board and hence the tube back in. I've been curious as to if the power supply recap was the issue with the smeared trace. We'll find out soon. Also on the way are green T1-3/4 LEDs to turn down in diameter for the function lights and a handful of 1800uF caps to restuff the cans.