Hi Everyone,
I'm in the middle of picking out capacitors for a recap project for my marantz pm7200, I figure its due by now, been 15 years old, and the thing runs like a toaster when on for a while, especially in class A mode, great for keeping the room warm 🙂
I opened it up and see almost ever capacitor inside it is a 85 degree elna cap, explains why it sounds warm , a tone I like.
All the caps used for cleaning up the DC rails are the same elna caps, such as the 220uf caps 2263,2264,2265,2566 on page 13 (the number is 15 at the bottom of that page) of the service manual.
The service manual is at
Marantz PM7200 - Manual - Stereo Integrated Amplifier - HiFi Engine
My question is, would using a high temperature nichicon like a 647-UBW1J221MHD1TO (mouser code) change the sound of the amp at the above locations (non-signal locations), or do these have to be elna caps to keep the sound as is. I wanted to use high temperature caps in all the locations that aren't on the signal path and assumed that changing these non-signal caps to high temps caps would be a good idea, but see marantz didn't do that in any of the locations in the amp and its making me suspicious....
I'm making all signal path caps elna silmic2 and have resigned myself to swapping them out over 7-8 years as they're 85 celsius caps.
Thanks
Dave.
I'm in the middle of picking out capacitors for a recap project for my marantz pm7200, I figure its due by now, been 15 years old, and the thing runs like a toaster when on for a while, especially in class A mode, great for keeping the room warm 🙂
I opened it up and see almost ever capacitor inside it is a 85 degree elna cap, explains why it sounds warm , a tone I like.
All the caps used for cleaning up the DC rails are the same elna caps, such as the 220uf caps 2263,2264,2265,2566 on page 13 (the number is 15 at the bottom of that page) of the service manual.
The service manual is at
Marantz PM7200 - Manual - Stereo Integrated Amplifier - HiFi Engine
My question is, would using a high temperature nichicon like a 647-UBW1J221MHD1TO (mouser code) change the sound of the amp at the above locations (non-signal locations), or do these have to be elna caps to keep the sound as is. I wanted to use high temperature caps in all the locations that aren't on the signal path and assumed that changing these non-signal caps to high temps caps would be a good idea, but see marantz didn't do that in any of the locations in the amp and its making me suspicious....
I'm making all signal path caps elna silmic2 and have resigned myself to swapping them out over 7-8 years as they're 85 celsius caps.
Thanks
Dave.
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The caps "longevity" rating is at rated temp and ripple and voltage.
Relax any of these parameters and the longevity increases. 85C is quite
hot, I doubt the amp would be much hotter than 70C, maybe measure.
All that said, 15years is not really a trigger for recapping, ok if
it's a learning exercise.
The UBW's are 135C rated, this is overkill. The basic specs of leakage
and tan delta are reasonable but slightly worse than an "audio" cap.
Note sure you would pickup the increase in leakage/noise.
I like audio caps (Nichi KZ, Silmic II's,,,) proping up the voltage
rails (C2263,,,) I would be uneasy about UBWs (extra leakage) in these
positions.
Nichicon Muse/KZ would be my pick, silmic II's my second choice.
Relax any of these parameters and the longevity increases. 85C is quite
hot, I doubt the amp would be much hotter than 70C, maybe measure.
All that said, 15years is not really a trigger for recapping, ok if
it's a learning exercise.
The UBW's are 135C rated, this is overkill. The basic specs of leakage
and tan delta are reasonable but slightly worse than an "audio" cap.
Note sure you would pickup the increase in leakage/noise.
I like audio caps (Nichi KZ, Silmic II's,,,) proping up the voltage
rails (C2263,,,) I would be uneasy about UBWs (extra leakage) in these
positions.
Nichicon Muse/KZ would be my pick, silmic II's my second choice.
Many thanks MBZ, so what I'm taking from this is the following,
the lower the tan delta, the better, high tan delta generate heat and all that goes with it
the lower the leakage, the cleaner the dc line to the signal circuits,
The idea of the very high temperature rating is that it'll last for many years, probably never needing swapping out again as it'll be run at a much lower temperature.
I must check out the spec of the KZ caps.
the lower the tan delta, the better, high tan delta generate heat and all that goes with it
the lower the leakage, the cleaner the dc line to the signal circuits,
The idea of the very high temperature rating is that it'll last for many years, probably never needing swapping out again as it'll be run at a much lower temperature.
I must check out the spec of the KZ caps.
Most electrolytic capacitors these days are rated at 85C, but some are rated at 105C.
Roughly speaking, every 10C derating doubles the capacitor life from the life spec,
all other things equal.
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An ideal cap will have zero tan delta/esr. For me it's just a measure of how
close to ideal the cap is. Keep in mind that the esr is made up imperfect
"welds" of component leeds to electrodes/plates amongst other things.
The cap leakage spec shows up as white noise. Most modern caps are good
however better to select appropriate item for phono/preamp stage eg,
Nichicon UKL or film (MKS2?)
I've been a long time user of Elna Silmic II's having recently switched to
KZ's. Perhaps they colour the sound, end result is amps sound more musical.
Apology for opinion...
My advice: Get an ESR meter. Also spot-check for leakage (and capacitance while you're at it) where this may be critical, unsoldering one leg. Then you should have a decent enough idea how the caps are holding up. Everything else is speculation.
That whole 105° thing is a bit of a farce. There are some 105° caps rated for 2000 hours and others for 10000 hours. That's a big difference. Basically you need to know the whole trio of rated temperature, ripple current and endurance to draw any meaningful conclusions. The same cap would post higher endurance if you eased up on ripple current and vice versa.
Be warned that low ESR is generally associated with higher leakage, which is not what you want e.g. for coupling caps. Also, higher leakage may mean shorter life. So reasonably low ESR is not bad, but I wouldn't use any of the high-strung series unless it's really needed... and it can't hurt to uprate voltage a bit. (You're generally fine with up to 3 times the DC voltage actually present.)
That whole 105° thing is a bit of a farce. There are some 105° caps rated for 2000 hours and others for 10000 hours. That's a big difference. Basically you need to know the whole trio of rated temperature, ripple current and endurance to draw any meaningful conclusions. The same cap would post higher endurance if you eased up on ripple current and vice versa.
Be warned that low ESR is generally associated with higher leakage, which is not what you want e.g. for coupling caps. Also, higher leakage may mean shorter life. So reasonably low ESR is not bad, but I wouldn't use any of the high-strung series unless it's really needed... and it can't hurt to uprate voltage a bit. (You're generally fine with up to 3 times the DC voltage actually present.)
Thanks for all the responses.
Its a given (for me anyway) that for DC coupling between opamp stages/volume/tone/signal path that it'll be silmic2 only.
My real question is for filter caps, like a 220u 63v cap on the amp board, this cap is between the dc rail and ground, I would have thought that current leakage here wouldnt matter, 2uA instead of 1 uA for example so long as it does generate much internal heat.
Its a given (for me anyway) that for DC coupling between opamp stages/volume/tone/signal path that it'll be silmic2 only.
My real question is for filter caps, like a 220u 63v cap on the amp board, this cap is between the dc rail and ground, I would have thought that current leakage here wouldnt matter, 2uA instead of 1 uA for example so long as it does generate much internal heat.
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Before getting too far into buying parts, I would do a thorough look over of what the differences are between the KI editions of the Marantz amplifiers. As I recall, they used some specific parts in certain places.
I found a manual for the one you have at HiFiEngine.com.
I found a manual for the one you have at HiFiEngine.com.
Hi,
Your read my mind, but n o way can I find the service manual for the KI version.
From what I see on the web, in crude dark and low res images, the differences I can see is the torroidal transformer and all the copper plating, I cant make out anything else, if anybody has the service manual for the KI version, it would be appreciated.
Ive read good and bad about the KI version, everything from snakeoil to a profound difference, and one where it actually sounded worse then the original version lol
Your read my mind, but n o way can I find the service manual for the KI version.
From what I see on the web, in crude dark and low res images, the differences I can see is the torroidal transformer and all the copper plating, I cant make out anything else, if anybody has the service manual for the KI version, it would be appreciated.
Ive read good and bad about the KI version, everything from snakeoil to a profound difference, and one where it actually sounded worse then the original version lol
I had looked at another model that had both regular and ki versions a available a year or two ago when a coworker was looking at one. I recalled seeing better coupling capacitors, that were still electrolytic parts, and a discrete op amp or two. The power supply capacitors were different as well.
The wima mks2 have been discussed as a better option than electrolytics for coupling, but I haven’t tried them myself. The better ones will be larger and won’t likely fit well. The regular Elba Silmics tend to strangely erase the midrange I have found, don’t use them.
The wima mks2 have been discussed as a better option than electrolytics for coupling, but I haven’t tried them myself. The better ones will be larger and won’t likely fit well. The regular Elba Silmics tend to strangely erase the midrange I have found, don’t use them.
Hi,
I've been looking at the caps in this amp again, what do people think of the following for the main psu caps ?
ALC10C153EF063 KEMET | Mouser Ireland
What in there at the moment are 2x marantz 12000uf 63v caps, but I cant find anything on the web saying how good or bad they are or how special/generic they are.
I'd like to put in something that's actually better then whats in there and will make a difference or atleast will not make the thing sound worse, they are 4 pin caps.
Also, I'm thinking of using nichicon PW and panasonic high temperature caps for all the power line caps, not just on the psu board, including the ones on the dc lines on the main amp board, the current ones there are elna silmic (I dont mean the ones in the signal path), would replacing these non signal caps with PW caps degrade the sound quality ? I'd prefer the PW's as they've a higher temp spec and seem to be made for power situations..
Also, in the tone board there are elna ROS and ROA caps, the writing on them is so badly faded , it was impossible to read them without using a really bright torch, almost invisible, I was wondering is this an indication of them been incinerated lol?, should you really replace these with their modern equivalents or is it ok to use nichi FG/KZ or silmic II's, would you notice the differance ??
Almost every cap in this amp is a elna silmic , with 85 degree rating.
I find this disturbing, this amp runs hotter then anything Ive ever seen in class A mode, I tried rebiasing it and its easy enough, you let it warm up as per the service manual, but then when you put the top lid back on, the thing heats up more and the bias changes, so you have to bias it with the lid on and in a similar place (shelves) to where it'll be run, this to me seems like a poor design, I'm thinking it would not have taken much circuitry to make this thing self biasing for temperature...
The caps on the main amp board run at 50 degrees celsius (>120F) when run in class AB mode with the volume down to zero, I'm nearly afraid to ever run this thing in class A mode after discovering that !
I realize this is not a 2k amp, cheap as chips in comparison, but really nice sounding, so its worth a little tlc.
I've been looking at the caps in this amp again, what do people think of the following for the main psu caps ?
ALC10C153EF063 KEMET | Mouser Ireland
What in there at the moment are 2x marantz 12000uf 63v caps, but I cant find anything on the web saying how good or bad they are or how special/generic they are.
I'd like to put in something that's actually better then whats in there and will make a difference or atleast will not make the thing sound worse, they are 4 pin caps.
Also, I'm thinking of using nichicon PW and panasonic high temperature caps for all the power line caps, not just on the psu board, including the ones on the dc lines on the main amp board, the current ones there are elna silmic (I dont mean the ones in the signal path), would replacing these non signal caps with PW caps degrade the sound quality ? I'd prefer the PW's as they've a higher temp spec and seem to be made for power situations..
Also, in the tone board there are elna ROS and ROA caps, the writing on them is so badly faded , it was impossible to read them without using a really bright torch, almost invisible, I was wondering is this an indication of them been incinerated lol?, should you really replace these with their modern equivalents or is it ok to use nichi FG/KZ or silmic II's, would you notice the differance ??
Almost every cap in this amp is a elna silmic , with 85 degree rating.
I find this disturbing, this amp runs hotter then anything Ive ever seen in class A mode, I tried rebiasing it and its easy enough, you let it warm up as per the service manual, but then when you put the top lid back on, the thing heats up more and the bias changes, so you have to bias it with the lid on and in a similar place (shelves) to where it'll be run, this to me seems like a poor design, I'm thinking it would not have taken much circuitry to make this thing self biasing for temperature...
The caps on the main amp board run at 50 degrees celsius (>120F) when run in class AB mode with the volume down to zero, I'm nearly afraid to ever run this thing in class A mode after discovering that !
I realize this is not a 2k amp, cheap as chips in comparison, but really nice sounding, so its worth a little tlc.
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I think for audio, you would want lower ESR main filters.
Many to choose from, including Kemet. I like United Chemi-Con
KMH/SMH series, in the larger amps. ESR 0.014 v 0.044(ALC series).
15000uf/63 or 80V is fine, need to carefully check available
space and pin/termination type.
Nichicon PW for power duties is a good choice. KZ/FG/Elna Silmic II's
likewise, even in the power supply. Slight preference for KZ/FG over
Silmic II's in the tone circuit.
The widespread use of 85C Silmic indicates that 85C meets the needs
and that they were going for sound quality over longevity, I like
this approach. Maybe use PW at the front end of the power supply and
KZ/FG/Silmic after regulators and on local power rails?
Don't stress about the 85C, certaily measure the temp, if it's above
80C then maybe reconsider, again, the rated life (2000hrs?) is when
operating at rated ripple&voltage&85C. Maybe go for 80V caps to ease
the concern? Service manual has the rails at 56V(AB) and 26V(Class A)
Maybe consider some external cooling like a laptop cooling fan maybe USD20-
Many to choose from, including Kemet. I like United Chemi-Con
KMH/SMH series, in the larger amps. ESR 0.014 v 0.044(ALC series).
15000uf/63 or 80V is fine, need to carefully check available
space and pin/termination type.
Nichicon PW for power duties is a good choice. KZ/FG/Elna Silmic II's
likewise, even in the power supply. Slight preference for KZ/FG over
Silmic II's in the tone circuit.
The widespread use of 85C Silmic indicates that 85C meets the needs
and that they were going for sound quality over longevity, I like
this approach. Maybe use PW at the front end of the power supply and
KZ/FG/Silmic after regulators and on local power rails?
Don't stress about the 85C, certaily measure the temp, if it's above
80C then maybe reconsider, again, the rated life (2000hrs?) is when
operating at rated ripple&voltage&85C. Maybe go for 80V caps to ease
the concern? Service manual has the rails at 56V(AB) and 26V(Class A)
Maybe consider some external cooling like a laptop cooling fan maybe USD20-
Many thanks MBZ,
One thing you said struck me, it got me searching on the web, suggestions that using audio grade caps for decoupling on the DC lines locally on the main amp board and tone board makes an audible difference, some say they can act as reservoirs for the local circuit, I had originally only thought of them as ridding any ripple or spikes from the lines and having no more effect on the signal path, have people experienced an actual audio difference using these caps in these positions?
Is this the real reason marantz used silmic caps for removing ripple from the dc lines all over the amp ? I had assumed it was a cost saving thing, allowing them to buy more in bulk.
One thing you said struck me, it got me searching on the web, suggestions that using audio grade caps for decoupling on the DC lines locally on the main amp board and tone board makes an audible difference, some say they can act as reservoirs for the local circuit, I had originally only thought of them as ridding any ripple or spikes from the lines and having no more effect on the signal path, have people experienced an actual audio difference using these caps in these positions?
Is this the real reason marantz used silmic caps for removing ripple from the dc lines all over the amp ? I had assumed it was a cost saving thing, allowing them to buy more in bulk.
Maybe an engineer will chime in...
I've always thought of it as reservoirs for local circuits.
Years ago I noted some Rotel CDP's had used "boutique" black gate
caps (about 220uf) on the opamp rails (pins 4 and 8). I noted that
maybe "quality"/size of local storage influences sound quality.
I would doubt that ripple in the tone circuits would be a significant
issue, the tone circuits normally feed off regulated supply having
very low ripple.
I think that Marantz using Silmic throughout was a push for improved
sound quality, they can be used for everything though there ripple rating
is bettered by others so their lifetime in power supplies may be slightly
reduces. Currently working on a NAD7120, All caps are elna except the
low leakage types, a hge improvement over the older NADs (3020, 3140, 3150,,,)
I've always thought of it as reservoirs for local circuits.
Years ago I noted some Rotel CDP's had used "boutique" black gate
caps (about 220uf) on the opamp rails (pins 4 and 8). I noted that
maybe "quality"/size of local storage influences sound quality.
I would doubt that ripple in the tone circuits would be a significant
issue, the tone circuits normally feed off regulated supply having
very low ripple.
I think that Marantz using Silmic throughout was a push for improved
sound quality, they can be used for everything though there ripple rating
is bettered by others so their lifetime in power supplies may be slightly
reduces. Currently working on a NAD7120, All caps are elna except the
low leakage types, a hge improvement over the older NADs (3020, 3140, 3150,,,)
Use good quality capacitors. That's it. Nippon Chemicon, Rubycon, Nichicon, Vishay, Kemet... pick one of those.
Hi,
okayyyyy, so I did a few updates to the amp.
I replaced every dielectric cap in the system, I was bored.
I used silmic 2 for the audio path, and a mix of nichicon PW's and high temp panasonics for power rail coupling.
I swapped out the 2 marantz 12mf 63v psu caps with kemets.
So I turned it on , OMG, I have just spent good money and time ruining a perfectly fine budget amp !!, it sounded smothered. ok, keep calm I told myself, remember the fabled silmic 2 burnin, so I left it on playing the tuner overnight, and hmmmm, to my shock it actually sounded alot better. I left it on for a week playing the tuner, and it made a considerable audible difference, now sounds alot more open, the sound was good, but the base had something missing ...
As advised in a post earlier in this thread, the kemets psu caps I had are not the best for audio, but as I already had them, I had to try them out, bad idea. Turns out the marantz 63v 12000uf caps sounded alot better , more reverb in the base, fixed the base problem.
Seems like alot of this amps sound characteristics comes from the main psu caps, I have to say I was surprised at how audible it was. These are the only caps with marantz on them.
So over all, its atleast as good as it was, I didnt destroy anything.
Now I'm curious to hear what it would be like with the nichicon KZ/FG caps in there instead of the silmic2s. If I get around to it , I'll be back.
okayyyyy, so I did a few updates to the amp.
I replaced every dielectric cap in the system, I was bored.
I used silmic 2 for the audio path, and a mix of nichicon PW's and high temp panasonics for power rail coupling.
I swapped out the 2 marantz 12mf 63v psu caps with kemets.
So I turned it on , OMG, I have just spent good money and time ruining a perfectly fine budget amp !!, it sounded smothered. ok, keep calm I told myself, remember the fabled silmic 2 burnin, so I left it on playing the tuner overnight, and hmmmm, to my shock it actually sounded alot better. I left it on for a week playing the tuner, and it made a considerable audible difference, now sounds alot more open, the sound was good, but the base had something missing ...
As advised in a post earlier in this thread, the kemets psu caps I had are not the best for audio, but as I already had them, I had to try them out, bad idea. Turns out the marantz 63v 12000uf caps sounded alot better , more reverb in the base, fixed the base problem.
Seems like alot of this amps sound characteristics comes from the main psu caps, I have to say I was surprised at how audible it was. These are the only caps with marantz on them.
So over all, its atleast as good as it was, I didnt destroy anything.
Now I'm curious to hear what it would be like with the nichicon KZ/FG caps in there instead of the silmic2s. If I get around to it , I'll be back.
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Hi everyone,
4 months have gone by and I've left in the silmicII caps, I like a warm sound,. so they're perfect for me. I know some hate them, but hey, everyone's different 🙂 If you like the pm7200's sound, then you cant go wrong with silmicII's in there instead.
So then I starting looking at the op-amps in this circuit, it uses a 2x NJM2114D dual opamp, one for the volume and another for the phono input, and 3x NJM2068D dual op-amps for the tone control.
After doing some digging on the web, I decided to replace the volume and 3 tone opamps with opa2134pa dual opamps, I've used sockets on all these so I can go opamp surfing if I feel the need to later on. I got them on mouser, so they're not some rebranded junk you might get on other websites.
This made a much bigger difference to the sound then the cap swap out ever did, night and day, more musical, more live and the base has a real good punch to it, but controlled and defined at the same time, not a bad thing on this amp as sometimes the base can be abit rumbly, for the lack of a better description. Looks like the original opamps were a significant contributor to that bad effect.
One thing that concerned me was the opa2143 has jfet inputs, while the originals are BJT's, so input impedance's are different, there seems to be no deleterious effects that I can hear due to any possible electronic issues, but maybe the audio gurus here could point out some changes to the circuit that would help if you can see an electrical problem with this opamp in there. There's no distortion or smoke yet 🙂 Is the THD worse ??, who knows, but Im not hearing anything that tells me to put the orig opamps back in.
At three quarters full volume, with no input signal, there is an obvious hiss/hum in the speakers, I don't think its any worse then it was before I did anything, but its not a issue anyway in the real world because my ears, speakers, plaster on the walls and especially neighbours would not be able to tolerate anything at that insane volume.
I was thinking of swapping in 4x LM4562 just to see if there was a difference, or if anyone can recommend other good opamps to try out, that would be great, (8pin through hole dual opamps only).
So to conclude, the original opamps are not bad, but you can really improve the sound of this amp by swapping out the opamps, a quick and inexpensive mod. If you have a vintage PM7200, go for it .
4 months have gone by and I've left in the silmicII caps, I like a warm sound,. so they're perfect for me. I know some hate them, but hey, everyone's different 🙂 If you like the pm7200's sound, then you cant go wrong with silmicII's in there instead.
So then I starting looking at the op-amps in this circuit, it uses a 2x NJM2114D dual opamp, one for the volume and another for the phono input, and 3x NJM2068D dual op-amps for the tone control.
After doing some digging on the web, I decided to replace the volume and 3 tone opamps with opa2134pa dual opamps, I've used sockets on all these so I can go opamp surfing if I feel the need to later on. I got them on mouser, so they're not some rebranded junk you might get on other websites.
This made a much bigger difference to the sound then the cap swap out ever did, night and day, more musical, more live and the base has a real good punch to it, but controlled and defined at the same time, not a bad thing on this amp as sometimes the base can be abit rumbly, for the lack of a better description. Looks like the original opamps were a significant contributor to that bad effect.
One thing that concerned me was the opa2143 has jfet inputs, while the originals are BJT's, so input impedance's are different, there seems to be no deleterious effects that I can hear due to any possible electronic issues, but maybe the audio gurus here could point out some changes to the circuit that would help if you can see an electrical problem with this opamp in there. There's no distortion or smoke yet 🙂 Is the THD worse ??, who knows, but Im not hearing anything that tells me to put the orig opamps back in.
At three quarters full volume, with no input signal, there is an obvious hiss/hum in the speakers, I don't think its any worse then it was before I did anything, but its not a issue anyway in the real world because my ears, speakers, plaster on the walls and especially neighbours would not be able to tolerate anything at that insane volume.
I was thinking of swapping in 4x LM4562 just to see if there was a difference, or if anyone can recommend other good opamps to try out, that would be great, (8pin through hole dual opamps only).
So to conclude, the original opamps are not bad, but you can really improve the sound of this amp by swapping out the opamps, a quick and inexpensive mod. If you have a vintage PM7200, go for it .
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Hi Dave,
I just bought a PM 7200 and I intend to start asap a recap and maybe to replace the opamps.
Please, do you have a list with all the replacements done in your MP7200? Or at least the shopping list(s) from Mouser? Will help me alot!
thank you
Dan.
I just bought a PM 7200 and I intend to start asap a recap and maybe to replace the opamps.
Please, do you have a list with all the replacements done in your MP7200? Or at least the shopping list(s) from Mouser? Will help me alot!
thank you
Dan.