Hi all, I'm restoring a Marantz 2252 that was given to me years ago. I have the lamps replaced and now about to recapping it. I'd to replace all the coupling caps (electrolytic) with Wima MKP10. However, the Wima is much much larger and won't fit on the board. What would be a nice and neat way to use Wima caps ?
I'm thinking about mounting a small PCB next to the input of the amp board for the Wima caps but not sure if the additional distance will pick up noise?
I know there are other smaller Wima caps such as MKS2/4 but based on my search most people won't use MKS2/4 in signal path.
Other than adding a PCB, what would you suggest as mounting options ?
p.s. I do have some 2.2uf ERO MKT caps that I'd to use for input coupling. The original Marantz input cap is 3.3uF. In case I go with the 2.2uF, will the low freq difference be negligible ?
I'm thinking about mounting a small PCB next to the input of the amp board for the Wima caps but not sure if the additional distance will pick up noise?
I know there are other smaller Wima caps such as MKS2/4 but based on my search most people won't use MKS2/4 in signal path.
Other than adding a PCB, what would you suggest as mounting options ?
p.s. I do have some 2.2uf ERO MKT caps that I'd to use for input coupling. The original Marantz input cap is 3.3uF. In case I go with the 2.2uF, will the low freq difference be negligible ?
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Yes, the difference will be negligible.
This is an upgrade i would never consider doing, especially not with something as hard to mount as a large WIMA. This will end up with long connecting wires and the caps being glued somewhere really inappropriate. At very best it will be an eyesore. Long term reliability will also suffer.
There are many types of good sounding electrolytics these days which will befit the quality of the amp much better.
The nfb decoupling cap 47/16 is also worth replacing with something you consider good sounding.
Can you fit some of the mks4, 4.7uf in the original locations?
I just did what you had suggested to another amp, and was able to keep the leads around an inch, the mkp10, 63V is a great part for the size, as I’m sure you’re aware. In my case the small cavity that contains the boards allowed for the parts to be tucked in securely against the case. The fact that the amp driver boards are contained within their own metal compartment is a bonus.
Long leads will usually lead to an unstable condition at some point, as they will pick up some rf and reap havoc.
I just did what you had suggested to another amp, and was able to keep the leads around an inch, the mkp10, 63V is a great part for the size, as I’m sure you’re aware. In my case the small cavity that contains the boards allowed for the parts to be tucked in securely against the case. The fact that the amp driver boards are contained within their own metal compartment is a bonus.
Long leads will usually lead to an unstable condition at some point, as they will pick up some rf and reap havoc.
My other choice would be Elna Silmic II series but not sure if they are comparable to film caps. The original caps in the amp are Elna but they are not Silmic II. They are brown in color.
The MKS4 is still too big compare to the original 3.3uf which has lead spacing of 3-4 mm. The MKS4 lead spacing is at least 19mm. That made me thinking an external side PCB just for mounting the Wima.
I would agree, yet a popular high end transistor amp uses those exactly.
The choice between Silmic, Panasonic FM and Nichicon FG is a matter of personal preference and i am confident any of these will improve upon the original caps.
And there is a third choice too: Panasonic ECP, which are SMD films. A friend has tried a stack of these as coupling and seemed to really like them. Three of four will fit easily but one needs to be careful with the soldering iron as those are easy to overheat.
ECP-U1C105MA5 Panasonic | Mouser Portugal
ECP-U1C105MA5 Panasonic | Mouser Portugal
If using an electrolytic, I would probably look for a Nichicon ES myself, same with the feedback cap, as was already mentioned.
Elna silmic II are just ok as a power supply part, seem to make the midrange disappear distinctly in certain frequencies. I have not bothered to measure this, just noticed when certain speech had been muted in some music. I wouldn’t use them for any coupling purposes.
I like the Panasonic film parts, would be a fun challenge but probably worth it.
Elna silmic II are just ok as a power supply part, seem to make the midrange disappear distinctly in certain frequencies. I have not bothered to measure this, just noticed when certain speech had been muted in some music. I wouldn’t use them for any coupling purposes.
I like the Panasonic film parts, would be a fun challenge but probably worth it.
I don’t put a lot of weight on that public opinion thing myself.
One of the first small parts I had purchased to use were the mkp1837, I could believe how bad they were after comparing to other parts. Plenty of people say they like those also. Interesting social experiment is all I can figure. Or maybe they sound a lot better than the 30+ year old parts that they replaced.
As for the mks2, while bottom tier for film caps, I would find it hard to believe that the sound (treble especially) could be better with an electrolytic. Are they really that bad? I have some here that were my backup in the event that the mkp10 didn’t fit somehow.
It’s all perception and individual taste I suppose.
One of the first small parts I had purchased to use were the mkp1837, I could believe how bad they were after comparing to other parts. Plenty of people say they like those also. Interesting social experiment is all I can figure. Or maybe they sound a lot better than the 30+ year old parts that they replaced.
As for the mks2, while bottom tier for film caps, I would find it hard to believe that the sound (treble especially) could be better with an electrolytic. Are they really that bad? I have some here that were my backup in the event that the mkp10 didn’t fit somehow.
It’s all perception and individual taste I suppose.
I think from all the options, it appears nobody vote for an extra PCB for the big Wima MKP10 caps.
It seems like I'm down to two options if I want something that fits easily - 1) new electrolytic caps, or 2) Wima MKS2.
I have always have good results replacing electrolytic with film caps but I have never used MKS2 whatsoever. To be fair, I have not listened to a good electrolytic coupling cap either. So, then, are some of those electrolytic caps mentioned comparable to film caps (I know its a matter of personal taste for most part).
I was about to pull trigger ordering from Digikey but I thought might as well heard from your opinion before I order.
It seems like I'm down to two options if I want something that fits easily - 1) new electrolytic caps, or 2) Wima MKS2.
I have always have good results replacing electrolytic with film caps but I have never used MKS2 whatsoever. To be fair, I have not listened to a good electrolytic coupling cap either. So, then, are some of those electrolytic caps mentioned comparable to film caps (I know its a matter of personal taste for most part).
I was about to pull trigger ordering from Digikey but I thought might as well heard from your opinion before I order.
Mylar dielectric capacitors can be quite bad sounding for coupling. There's no reason to use them,
since polypropylene types are readily available for a similar cost.
Size is the main issue for the op, not dielectric quality or cost that I am aware of. It was stated in the first post I believe. Mylar caps are indeed smaller than polypropylene.
I chose to make a puzzle and install (cram in) my mkp10s, leaving the Mylar parts for another day, knowing the polypropylene parts are better.
So how short can the leads be made using the mkp10s? There will be a practical limit on how much antenna is created after the rf filter at the entry of the amp. I have found out the hard way that you don’t want to exceed this.
I have on hand, used the Silmic II caps, while they are a fine part, they sounded soft or slightly omissive, I would/or will moving forward, only use them on 'more forward sounding' gear... I am a big Nichicon MUSE fan, have had very uniform experiences in every build, ~ if the parts will fit ~ in the original parts place.
A Nichicon ES bipolar with a .1 or .01 WIMA bypass is very neutral for inter-stage coupling roles.
A Nichicon ES bipolar with a .1 or .01 WIMA bypass is very neutral for inter-stage coupling roles.
I remember these well. Bought a lifetime supply based on a cap-guru site proclaiming them capable of turning water into wine as bypasses
But let's not forget this specific discussion is about improving a very average amp.
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