Starting Marantz 2325 rebuild

Oh boy. This thing rocks with loads of power and authority! This rebuild went a lot quicker than usual due to all the info documented here. I will add that its wise to draw a diagram of where all the wires go on the Dolby board!

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Letting it warm up now for the next 30 mins or so. Then going to dial it again and then it's time to hook up the massive dummy loads and see what it's really capable of! :D
 
She sings without clipping up to 147 wpc at 1khz

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And people say these things are "overrated"! Ha!

One thing I did notice is that the loudness button has very little-no effect on the bass. The bass knob functions fine as do the others. The loudness button effects mid and treble only on both channels. I pulled the tone board and panel down but haven't noticed any wires broken off or bad solder joints. Hmm. Any idea?
 
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Congratulations and great job! What are your speakers? It definitely makes a difference with my KHorns and I use it a lot.
 
The loudness button definitely boosts the bass on mine. Not sure what’s going on there. Maybe more Deoxit of switch?
Steve

I flooded the switches 3 times over the course of 2 days and worked the switches about 200 times in and out.

I'm going to put it through some paces today to make sure everything else is working properly then I'm going to pull the PU01 board again and double check everything. Looking at the schematic, the issue could also be on PE01 as the loudness switch is wired directly to it. There's got to be a solder bridge or something I'm missing. I did recap that board late at night after work and was pretty tired while doing it. Thank you for the advice Steven.
 
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Congratulations and great job! What are your speakers? It definitely makes a difference with my KHorns and I use it a lot.

Its definalty not the speakers. This is what I originally thought because my desktop/test speakers are small but while on the scope, I saw no db boost in the low frequency range.
 
Haha! It's not that bad actually, especially with the tone board have a connector!

I pulled it and reflowed everything. Found a couple questionable joints that I just of missed on my first inspection. Had to use a lot of light and a large magnifying glass to spot them though. Darn astigmatism.

While I had the tone board out I reflowed it and replaced the transistors on it as well. I think it may have been related to the tone mode switch. After putting the boards back In i was listening and flipped the tone mode switch back and forth a couple times and was getting a crackle when reaching the out position. Gave it a good cleaning and everything is functioning perfectly. Man this thing has some fat bottom end! Have it doing home theater duty to cap off a Harry Potter marathon :D

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Hello Guys!
I've made an online BOM of all components mentioned in this thread (as I understand, this list is largely inspired by Leestero's thread on the 2325 restoration), with links to the specific Mouser product pages. I hope it's okay I share this link here. I have not modified any part, some items are currently out of stock, but you should be able to find suitable replacements.
I make this list for myself as I'm planning on doing this restoration as soon as I get all the parts, and I thought it would be nice to share it with others stumbling on this excellent thread. Thanks Steven Tate, and Leestereo!

So here's the link: https://docs.google.com/spreadsheets/d/1JaAcbN-dXUsYx6ALQSoBtqMAwV9E9TQXRI0nVWu_42I/edit?usp=sharing

I'm new to the forums, so if sharing this might be a problem, please remove this post! If anyone wants to edit the list, shoot me a pm or something, and I can send you an editable version or something?

That list is great. Saved me a lot of time. I ordered every part on the list, but found the relay doesn't fit my board. My board has a different layout than the one done in the thread. My unit has a 1976 date on the inside of the faceplate. Posting two pics. First is the one rebuilt on this thread, the second is my board. People will need to determine which board they have before ordering parts. IMG_1670_zpsihfdj3jf.jpg IMG_20191109_092301471a.jpg
 
Recapping my P700 board and found this 27k resistor with outer layer peeling(see pictures). I would like to ask members of this forum for advice to make sure I am ordering the correct part. Thank you.

Was just heading to bed when I saw your post. There looks to be quite a few resistors on that board that look suspect. R723, R722, R718, R726 possibly. Check all of them before ordering replacements.
 
Hello. My problem is the P700 . When it connected the relay not working.
Somebody please give me an idea.
 

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Blown output transistor somewhere on one of the amps. Unplug the power connector (power off), one at a time and turn it on to see if that's it.
 
Blown output transistor somewhere on one of the amps. Unplug the power connector (power off), one at a time and turn it on to see if that's it.
I am sorry. I don’t understand what you mean.
I found out the amp on right side have this problem
 
I am sorry. I don’t understand what you mean.
I found out the amp on right side have this problem
There is a white connector that powers the amp board. He was suggesting you disconnect that connector and power up the receiver. If the relay works, you know the problem is on the amp board or an output transistor.
 
There is a white connector that powers the amp board. He was suggesting you disconnect that connector and power up the receiver. If the relay works, you know the problem is on the amp board or an output transistor.
Did you mean. Disconnected this white wire right?
 

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If the amp is already out, the plug is disconnected. It connects to those four vertical pins just above your circles. With that amp out, does your relay click?
 
P600 Dolby Circuit Board

This one is a veritable pleasure to work on because the whole board comes out and you can work on it on the bench. Lots of 10uF caps on this one just like the tuners. Here is the board after replacing all electrolytic caps - nothing else - and the parts list. Had a shipping issue with the parts I'm waiting on. It's been five days since I ordered from Mouser, and they usually get here in two days. The Mouser warehouse is about 10 miles from here. After five days, no parts, so I checked the USPS tracking. The parts went from Mansfield (10 miles from me) to Ft. Worth (about the same) and then to Amarillo (300 miles away!) then finally back to Ft. Worth where they are now. I will probably get them tomorrow. The system obviously hiccuped on my parts. :mad:

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P600 Dolby Circuit Board

C601/602 3.3µF/25V - WIMA MKS2 3.3µF/50V Mouser 505-MKS23.3/50/10
C607/608/609 10µF/16V - Nichicon KL 10µF/16V Mouser 647 UKL1C100KDD1TD
610/611/612
613/614/623
624/631/632
635/636
C627/628 47µF/10V - Nichicon FG 47µF/25V Mouser 647-UFG1E470MEM
C641 220µF/25V - Nichicon KL 220µF/35V Mouser 647-UKL1V221KPD


Steven, I'm currently working on this board in place, but just read this where you are able to pull the board out without unwrapping the leads? I do notice the leads have an rubber wrap around them? can these be pulled out and plug back into the jumpers?
 
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