Marantz 2325 experts please

Echoplex

Active Member
My 2325 is having a few minor issues...

The main speaker button/switch will not engage, but I found the culprit: faceplate grommet has come loose and is preventing switch from traveling to latching point. What brand and type of glue should I use to put it back?
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Also, both P700 amp modules have corroded 1.2K 2W resistors @ R719. Would it be ok to use 3 watt versions for these instead?
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C714 cap with slight bulge on side. What should I use to replace it with?
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Lastly, P800 power supply rectifiers H808/H809....I still have the originals ones in place, and since I've already got this thing torn apart, I'd like to replace them as well. Part numbers and any suggestions are welcome!
Thanks much!
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The original grommet glue looks to me like Pliobond or 3M weatherstrip adhesive. I generally use Loctite Stick' N Seal Indoor adhesive. Be sure to get the Indoor stuff, it's acrylic, water clean up and dries clear.

I use 3W resistors there too, Panasonic ERG-3SJ122. I leave the leads long like the original ones. I also leave a little nub of lead protruding out the solder side of the board so the solder can have more to hang on to, those resistors get hot!
The zeners (H716/H717) dissipate about a watt, so I like to replace those with 3W versions too, ON-Semi 2N5932B, leave their leads long as the leads are the heat sink.

H808 and H809 are regulators, not rectifiers. I like to use On-Semi MJ15030 TO-220 parts for those. Be sure to use a little thermal compound between them, the mica insulator and the heat sink.

The bulge on the cap might be glue or something. Those ceramic coated film capacitors almost never fail under the conditions they are subjected to in this application.

The 2325 is one of my favorites!

Tom
 
Thankyou Tom!

Oh yes, the 2325 is an amazing piece!

Good to know about C714 cap... thought for a minute there that there might be some issue due to heat damage/age. But heck, other than the switch failing to latch, I haven't had any problems.
Just forgot that this thing has over 20,000 screws to unbolt. :D

Want to be sure I'm understanding you....
So, for H808/H809.... are those the dual diodes (DS-131B) common cathode?
And the regulators, (Sanyo D331E) are the ones attached to the large heatsink?
 
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My 2325 is having a few minor issues...

C714 cap with slight bulge on side. What should I use to replace it with?
Lastly, P800 power supply rectifiers H808/H809....I still have the originals ones in place, and since I've already got this thing torn apart, I'd like to replace them as well. Part numbers and any suggestions are welcome!
Thanks much!
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Be sure you order Common cathode on those rectifiers H808,809. I got the wrong ones and that was an expensive mistake. Mouser part # 863-MUR1620 CTG
 
The original grommet glue looks to me like Pliobond or 3M weatherstrip adhesive. I generally use Loctite Stick' N Seal Indoor adhesive. Be sure to get the Indoor stuff, it's acrylic, water clean up and dries clear.

I use 3W resistors there too, Panasonic ERG-3SJ122. I leave the leads long like the original ones. I also leave a little nub of lead protruding out the solder side of the board so the solder can have more to hang on to, those resistors get hot!
The zeners (H716/H717) dissipate about a watt, so I like to replace those with 3W versions too, ON-Semi 2N5932B, leave their leads long as the leads are the heat sink.

H808 and H809 are regulators, not rectifiers. I like to use On-Semi MJ15030 TO-220 parts for those. Be sure to use a little thermal compound between them, the mica insulator and the heat sink.

The bulge on the cap might be glue or something. Those ceramic coated film capacitors almost never fail under the conditions they are subjected to in this application.

The 2325 is one of my favorites!

Tom

Sorry Tom, he's right. The H808 and 809 are dual common cathode rectifiers located on the left side of the power supply right behind cap 803.
 
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I use 5 minute epoxy when regluing the grommets. Almost anything works though!

The glob on the cap is just wax that they used to dip them in. Maybe always that way or the years of hot running and on it's side would do that. [:biggrin:] J/K!!
 
...So, for H808/H809.... are those the dual diodes (DS-131B) common cathode?...

If you prefer a "soft recovery" type, the Vishay BYQ28E is available from Mouser (https://www.mouser.com/ProductDetail/Vishay-Semiconductors/BYQ28E-200-E3-45?qs=kop3EGWU%2bIt67Q6mQhs7oA==).
Also consider replacing the large 150 ohm/5W dropping resistor (R801) with a physically smaller 150 ohm/7W one (https://www.mouser.com/ProductDetail/Welwyn-Components-TT-Electronics/W22-150RJI?qs=sGAEpiMZZMtbXrIkmrvidG3jfhV0pGvzKSidaBstp/Y=); it allows better air flow around the surrounding components and has a much improved temperature coefficient.

power supply restored upgraded1.jpg
Picture from Leestereo's Restoration and Upgrade Of A Marantz 2325
 
I use 5 minute epoxy when regluing the grommets. Almost anything works though!

The glob on the cap is just wax that they used to dip them in. Maybe always that way or the years of hot running and on it's side would do that. [:biggrin:] J/K!!

Thanks Randy!

Yeah, there's no telling what my 2325 went through in it's former life. It was a mess when I got it, and it reeked of smoke! 1,000 cotton swabs later and an isopropyl bath did the job though.:D
 
If you prefer a "soft recovery" type, the Vishay BYQ28E is available from Mouser (https://www.mouser.com/ProductDetail/Vishay-Semiconductors/BYQ28E-200-E3-45?qs=kop3EGWU%2bIt67Q6mQhs7oA==).
Also consider replacing the large 150 ohm/5W dropping resistor (R801) with a physically smaller 150 ohm/7W one (https://www.mouser.com/ProductDetail/Welwyn-Components-TT-Electronics/W22-150RJI?qs=sGAEpiMZZMtbXrIkmrvidG3jfhV0pGvzKSidaBstp/Y=); it allows better air flow around the surrounding components and has a much improved temperature coefficient.

View attachment 1181625
Picture from Leestereo's Restoration and Upgrade Of A Marantz 2325

Thanks Lee!

I've been reading and enjoying your 2325 restoration thread thoroughly, and others here as well. Lots of good information! Speaking of, your photos linked from photobucket are not showing up in your restoration thread. It would be nice to see them for reference.

I'm comparing the Vishay and On-Semi rectifiers on Mouser.....don't think I can go wrong with either choice. I'll also look at replacing R801 resistor.

I've now gotten completely curious and pulled PE01 board out as well...more photos and questions to come.:biggrin:
 
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...your photos linked from photobucket are not showing up in your restoration therad. It would be nice to see them for reference...

Photobucket has changed its 3rd party hosting policy and this has many of my AK threads. However, the embedded Photobucket pictures can be viewed with a Chrome Extension or a Firefox Add-on. I have noticed that at different times one or the other workaround will stop working; currently, at the time of writing, both workarounds allow the pictures to be viewed within the thread.
 
Ok, more goodies...

Removed PE01 tone board last night ...mine has a variety of electrolytics in locations where I notice a lot of folks here are using Wima films almost exclusively. What are the reasons for this? Longer life, improved sound, tighter tolerances etc?
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I know small lytics tend not to last as long, but I wonder if by replacing any of these to films I would be able to tell a difference and improve the sound? Or just have the peace of mind knowing I won’t have to replace them as often?
 

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...Removed PE01 tone board last night ...mine has a variety of electrolytics in locations where I notice a lot of folks here are using Wima films almost exclusively. What are the reasons for this? Longer life, improved sound, tighter tolerances etc?

I know small lytics tend not to last as long, but I wonder if by replacing any of these to films I would be able to tell a difference and improve the sound? Or just have the peace of mind knowing I won’t have to replace them as often?

Film capacitors have lower ESL, ESR and leakage than electrolytic types, which is preferred in the signal path. How does this translate in performance? Lower noise and less distortion; how audible this is in the the real world is a case of the "ears of the beholder" ;-).
 
I replaced those with WIMA films on the 2325 rebuild that I did (probably based on Leestereo's rebuild thread). All I can say is it certainly didn't hurt anything. That's one of the best sounding receivers I've ever heard.
 
To expand on the use of capacitor types for signal path duty: for capacitors that are ≤4.7µF, stacked film types are generally small enough to replace the original electrolytic type. For larger values, one can install bi-polar types (e.g., Nichicon ES). This approach is largely derived from the published work of Cyril Bateman examining the impact of capacitors on sound quality: https://linearaudio.nl/cyril-batemans-capacitor-sound-articles. He tested electrolytic capacitors extensively and demonstrated that in AC coupling, bipolar electrolytic capacitors have the lowest distortion/noise of all the electrolytic types (even the presence of a polarizing voltage) and that film capacitors are generally lower distortion/noise than electrolytic capacitors of any type.
 
Good stuff there Ben! Thanks for posting the article.

I’m going to do some updates per your rebuild thread...order all of the same caps, resistors you and others have done, but have a few questions first.
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R816 resistor has another resistor piggybacked to it underneath the board. Does this need to stay or be removed?
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Also, the large main filter caps have panasonic coupling caps added underneath as well.
Should these stay, or be removed also?

Thanks much!
 

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_DSC0285.JPG My P800 board didn't have that resistor underneath but I don't know what's been done to your board previously. Here's what I did to mine. I can also post a labeled photo of PE01 if you like?
 
Keep the 150 ohm ceramic up off the board for dissipating heat.
The resistor under the board must be someones fix for not having the correct value.
I suggest checking to see if any other resistors were replaced and to keep things accurate with the schematic.
R816 should be one 390K ohm 5% 1/4watt.
The bypass caps on the filters could be fine as is, but i have read somewhere that placing them right where the power comes into the amp board is better.
Lots of mixed opinions on stuff like that, so sometimes you have to go by your own ears.:)

As far as films go, try to go polypropylene if you can find correct sizes that fit.
 
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