Mundorf MLytic AG+ 4-Pole cap users : beware of wiring, some of us got it wrong !

Bert 1100

Super Member
Hi all,
After reading about these 4-Pole power supply caps, I decided to give them a try.
I was looking here and there about how to connect them, since the schematics on Mundorf's site do not include the actual markings found on the caps themselves, making it unclear.

I found the thread by Flaxmill19 about his 140, where he drew up a wiring diagram : http://audiokarma.org/forums/index....0-stereo-power-amp-–-restoration-work.562617/

So I wired it up like this in a Scott A457 I'm restoring for someone. It works perfectly well, but I still had doubts so I shot an email to Mundorf directly, and they replied within an hour.
AND IT SEEMS WE GOT IT WRONG......

Here is the exchange I had with Mundorf :
(Note I've added the pink "WRONG" afterwards so nobody would use the pic as a guide...)

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MY MESSAGE TO MUNDORF:

Hello,
I am using your MLytic AG+ 4-pole capacitors in building and restoring audio amplifiers, and I wanted to be sure I understand properly the way they should be wired.

The schematics given on your web site ( 4-Pole mlytic application note) is very clear, but I have difficulty because the markings on the capacitor ( +in +out -in -out) are not indicated on that schematic.

So I have written in GREEN on the schematics provided on your website the equivalent markings found on the capacitors. Please let me know if I am correct with what I added on the schematics.

If what I have written in green is wrong, please let me know and show me the proper way :)

M-Lytic AG+ 4-Pole WRONG.jpg

To sum it up :

pin 1 = + IN
pin 2 = - OUT
pin 3 = + OUT
pin 4 = - IN

Is that correct ?

Thank you, your help is much needed and appreciated !

Bertrand Métrailler
Switzerland


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THE ANSWER FROM MUNDORF :

Dear Mr. Métrailler,
Pinout.jpg
Hoping this pinout drawing is helpful for you.
The unmarked and set back pin is Out-.
Transferred to the application note this means:

MLytic AG+ 4-Pole RIGHT.jpg


1. IN+
2. IN-
3. OUT+
4. OUT-


Kind regards,
Mirko Filke
Head of Sales & Supply Chain
Mundorf EB GmbH
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SO ! I got it wrong and it seems some of us as well.
This means the minus poles need inverting, so yes it does work fine but is not optimal and as intended by the manufacturer.
I'll be rewiring the amp I did. About its sound before and after I will not check, since It's in the middle of the restoration work.
Hope this is useful and helps !
 
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Good information, well done for chasing this down and setting the record straight. :thumbsup:
 
What is the point to conduct the return through the capacitor, re. IN- > OUT-, rather than just a single return to ground?

I see the notes on the schematic of apparently isolating the charge current from the working current, but what does that gain?
 
What is the point to conduct the return through the capacitor, re. IN- > OUT-, rather than just a single return to ground?

My understanding is that the current is made to flow through the actual capacitor plate or electrode, rather than a connection to the plate, this is highly advantageous apparently - not sure exactly why - eddy currents? charge distribution?
 
I have no idea how the 4-pole is supposed to be better than the 2-pole caps, haven't done enough reading yet, maybe even then I won't get it :biggrin:
But I trust the manufacturers and the people on AK who have used them :)
 
Hi Bert,

Very interesting response from Mundorf, my two amps with the 4 pole caps fitted with your original connections sound great, so please once you have run your amps with the Mundorf connections, please report back to the forum your thoughts on the sound.

Tony
 
Definitely will, although the amp I'm putting the caps in is not my amp, and I'm not very familiar with how it sounded before the restore. But I did give it a listen beforehand.
And I'm wondering how much difference comes from the proper direction of current flow. The most difference is likely from the construction of the cap ?
I have a 1060 (mine this one :) ) that I started on and I want to use a 4-pole there as well, maybe a Jensen ? But I got to get it fixed first, only then onto a restore....
 
Update, the Scott A457 with the Mundorf 4-pole caps is now finished and running. The sound is very very nice.
I did an A437 just before the 457 (still both here), with basically the same parts, only the main caps in the 437 are Nichicon KG (other caps are Elna Silmic II, and some films)
The two amps are very similar in build, the 457 being more powerful.
Before the restore, both sounded pretty much the same : bass a bit boomy, not deep, treble sharp and with no "sparkle".

Now, they both sound very nice, the bass is better, less boomy and deeper. The midrange nice and the treble also improved a lot.
The difference is quite noticeable between the two : the 437 in comparison sounds closed in and has less detail.

The 457 with the 4-poles really sounds very open and airy, with very small details and low level sounds clearly audible. Very 3D. Especially nice with strings, a very snappy dynamic sound that the 437 lacks. Very life-like, mostly with acoustic instruments and "real" sounds.
So to me it was definitely worth putting these caps in. Now, is there a difference between the two ways of connecting them ? I can't say since I only heard the "wrongly" connected caps for a few seconds to make sure it worked.
I'm now doing my Marantz 1060, definitely will go for a 4-pole, still trying to decide Mundorf or Jensen....the price difference is quite big.
 
Update, the Scott A457 with the Mundorf 4-pole caps is now finished and running. The sound is very very nice.
I did an A437 just before the 457 (still both here), with basically the same parts, only the main caps in the 437 are Nichicon KG (other caps are Elna Silmic II, and some films)
The two amps are very similar in build, the 457 being more powerful.

Hi Bert,
Have you fitted Mundorf 4 pole capacitors to both the A457 & A437? Sounds like I will have to seriously consider changing my wiring on my two amp's 4 pole capacitors. Thanks for the feedback Bert. I will be interested to hear how your 1060 turns out as well.

Tony
 
Hi Tony, no, the A437 has Nichicon KGs (the "B" ones, not Super Through).
Only the A457 has the 4-pole Mundorfs.
 
I am planning to use a 100uf Mundorf MLytic AG+ 4-Pole cap to replace a 40uf electrolytic in the HK Citation II. In the picture it is C3, the cap in the middle.

Currently the cap grounds on the metal plate that holds it. What should I do with the two Negative poles of the 4 pole cap? Should I connect both to the same ground / plate?

How could I separate them otherwise?

citation6.jpg
 
Gvocale, is C3 a power supply cap ? You need to work out with the schematics what this cap does and which wires are which so you can separate the ins and outs...
It might not be possible....in which case yes you can connect them to the same ground.
Maybe you can provide us with a schematic ?
 
I guess here you need to have the grounds together. Most likely this will not make much difference, if any. I've been using different makes of 4-pole caps and for example with the DNM 4-pole, even though there are 2 minus posts, they require the grounds be connected together.....
 
Hi guys, I'm thinking of using the 4-pole MLytics in the Power Supply of a Sanui au-7500. However, the original 6.800uF psu caps have an additional bypass capacitor (0,22uF) between their + and - poles. Does this mean that to recreate that configuration for each of the large caps I have to put in 2 bypass caps of half the value (0,11uF), since caps in parallel add up? Or are they technically in series (in which case I'd have to use two .44 bypass caps)? Or is the way to go a different one altogether? I'm grateful for your help!
 
Does this mean that to recreate that configuration for each of the large caps I have to put in 2 bypass caps of half the value
Here the value of the bypass cap is really not very important. Bigger is better but size and price are the limits. I would use maybe 4.7uF film caps. or 1 uF. or whatever you have on hand that is close.
4 bypass caps total needed.
1 cap MINUS IN to PLUS IN for each big cap.
1 cap MINUS OUT to PLUS OUT for each big cap.
 
Merci beaucoup, Bert! That is very helpful. I'll be sure to report back once I've undertaken this endeavour and maybe post some pics of the results [provided that I don't fail].
 
Hi folks,

Sorry to ask it here, but it's for an old amp with one single filtering electrolytic cap as show below,

sqli6w.jpg


10cno83.jpg

I have here one Mundorf M-Lytic (6800uF/80V) 4-poles. The doubt is if I just connect the two "+" (in and out) together, and the two "-" (in and out) also together...

14iz78i.jpg
 
No, at least the pluses can be divided : from rectifier (B1) to plus in, then to amp from the plus out.
Not sure if you can divide the minuses, since there is only one wire going to the cap.
 
...
Not sure if you can divide the minuses, since there is only one wire going to the cap.
Yes, that's my main concern.

So the pluses can be divided: one red wire comes from rectifiers (B1) to the "in +" and, from the "out +" pole, the other red wire goes to the fuses?
 
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