Author Topic: Mingda MC34 -how to remove beauty rings ?  (Read 14523 times)

Offline donberry

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Mingda MC34 -how to remove beauty rings ?
« on: October 09, 2014, 08:53:35 AM »
I have the older version of the MC34AB - doesn't have the power meter on it, and it has made a scratchy noise for the longest time but I am just now getting around to working on it. Could be wrong and often am, but I have a feeling it is because of some loose tube sockets. None of the sockets could be said to fit like a glove, but 3 in particular are pretty loose. Even if it doesn't fix the noise, still needs done.
I have not examined the heck out of it yet but just did a cursory look - I didn't really see how the beauty rings are attached.  I don't think there is access to them from inside the unit, so I am guessing they are just press fitted or screwed on ?

Figured as long as I am going to be doing that much soldering I may as well finally change the film caps. I didn't splurge on them, just picked up the Mundorf Supreme MKP for the .22uf, have not decided on the 1.0uf. As there are 8 of them it's not going to be too cheap so still trying to decide which way to go. Was looking at some obbligato gold, but couldn't make up my mind so still trying to decide. Wishing I had went with a better .22 cap already but figure I will give them a listen and see how they sound as they won't be hard to change

any info on the beauty rings appreciated

Offline oceangreen17

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #1 on: October 12, 2014, 02:32:57 PM »

Also on this topic does anyone have a schematic of the Ming Da MC34 they could possibly pm me?

I recently purchased the famous modded Ming Da and are very curious to research some possible ..... further mods.

The original schematic would be very helpful.

Will report back soon.

Thanks 

Steve 

Offline stevenvalve

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #2 on: October 12, 2014, 03:32:44 PM »
I have the older version of the MC34AB - doesn't have the power meter on it, and it has made a scratchy noise for the longest time but I am just now getting around to working on it. Could be wrong and often am, but I have a feeling it is because of some loose tube sockets. None of the sockets could be said to fit like a glove, but 3 in particular are pretty loose. Even if it doesn't fix the noise, still needs done.
I have not examined the heck out of it yet but just did a cursory look - I didn't really see how the beauty rings are attached.  I don't think there is access to them from inside the unit, so I am guessing they are just press fitted or screwed on ?

Figured as long as I am going to be doing that much soldering I may as well finally change the film caps. I didn't splurge on them, just picked up the Mundorf Supreme MKP for the .22uf, have not decided on the 1.0uf. As there are 8 of them it's not going to be too cheap so still trying to decide which way to go. Was looking at some obbligato gold, but couldn't make up my mind so still trying to decide. Wishing I had went with a better .22 cap already but figure I will give them a listen and see how they sound as they won't be hard to change

any info on the beauty rings appreciated
obbligato gold, I think they are oil filled, generally oil caps have fuller, fatter, more weightier base than standard film caps of the same value, I find you can get away with running smaller caps than specified by the manufacturer. Are the Mundorf Supreme MKP for the .22uf oil filled.

Offline stevenvalve

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #3 on: October 12, 2014, 03:35:11 PM »
Also on this topic does anyone have a schematic of the Ming Da MC34 they could possibly pm me?

I recently purchased the famous modded Ming Da and are very curious to research some possible ..... further mods.

The original schematic would be very helpful.

Will report back soon.

Thanks 

Steve
  The WA crew may have one, they where really into these amps.


Offline data

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #4 on: October 12, 2014, 05:14:53 PM »
I think I have the copy here somewhere, will have a quick look..

Offline kajak12

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #5 on: October 12, 2014, 05:19:20 PM »
Also on this topic does anyone have a schematic of the Ming Da MC34 they could possibly pm me?

I recently purchased the famous modded Ming Da and are very curious to research some possible ..... further mods.

The original schematic would be very helpful.

Will report back soon.

Thanks 

Steve
pm me your email for a schematic...........
still discovering the link between electronics and audio reproduction.so much to learn and so little time

Offline data

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #6 on: October 12, 2014, 05:43:34 PM »
  obbligato gold, I think they are oil filled, generally oil caps have fuller, fatter, more weightier base than standard film caps of the same value, I find you can get away with running smaller caps than specified by the manufacturer. Are the Mundorf Supreme MKP for the .22uf oil filled.
I don't think the Mundorf MKP series are oil filled, neither are the obbligato gold... at least I don't think so. Although I'm confused my the use of MPK and the SUPREME notation, the SUPREME is a polypropylene, and the the MPK series are metalized polypropylene.

But the obbligato gold do have that sound you have described before, rich and full. A nice cap for not much $.

Edit: Damn....now I want to dissect an obbligato gold, I'm curious :)
« Last Edit: October 12, 2014, 05:52:23 PM by data »

Offline donberry

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #7 on: October 12, 2014, 06:08:21 PM »
no, neither of those are oil filled. I have used the oil filled in speakers, pair of HPM-150, taming the midrange. Worked very well.

pm on the way kajak - thank you.

so no one knows how the beauty rings come off ?
« Last Edit: October 12, 2014, 06:10:23 PM by donberry »

Offline data

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #8 on: October 12, 2014, 06:14:52 PM »
I'm still curious as to the construction of the obbligato gold caps, I have them in my crossovers.

The Mundorf line up of capacitors are very confusing, they used to have the SUPREME and then the oil impregnated SUPREME "silver & oils" and the silver/gold oils" Now with new lines including the MPK and the EVO range and some of those EVO range are oil impregnated.

Offline donberry

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #9 on: October 13, 2014, 01:57:38 PM »
data - with the mundorf if it has oil in it, it will be in the name - i.e. silver in oil, Mcap evo oil, etc....with obbligato, same thing really tho they only make the one line of caps with oil in them if I am not mistaken.

Offline donberry

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #10 on: October 13, 2014, 02:00:11 PM »
big THANK YOU to kajak12 for taking the time to get me the schematics for this amp.

Offline data

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #11 on: October 13, 2014, 03:24:10 PM »
data - with the mundorf if it has oil in it, it will be in the name - i.e. silver in oil, Mcap evo oil, etc....with obbligato, same thing really tho they only make the one line of caps with oil in them if I am not mistaken.
Yup, that is what I was trying to point out when i was talking about the various Mundorf ranges, but they still make their cap designations confusing with so many ranges. And yeah, Obbligato just have the one and It's a power supply cap :)

All the best with the Ming Da, nice amps.

Offline data

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #12 on: October 13, 2014, 03:59:16 PM »
BTW Don.

I'm still interested in what cap you are talking about when you said "Mundorf Supreme MKP" ?

The Mcap Supreme (polypropylene)?
Or one of the MKP range?
« Last Edit: October 13, 2014, 04:13:17 PM by data »

Offline data

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #13 on: October 13, 2014, 10:19:59 PM »
OK, I'll guess that they are the Mcap Supreme (polypropylene).

Offline donberry

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #14 on: October 14, 2014, 02:45:59 AM »
These are the caps I bought  -- http://www.partsconnexion.com/capacitor_film_mundorf_suprm.html
Got them in and they are a lot bigger then I thought they would be, is what I get for not looking up the size. I'll find a way to squeeze them in tho.  :)
Finishing up a project in the house then going to start on replacing the tube connectors if I can figure out how the beauty rings come off without scratching them all up.

On a side note - hooked the amp up, 1st time I have used it in a LONG time - forgot how good it was. Of course now that I ordered the tube connectors it isn't making that noise anymore.

Offline data

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #15 on: October 14, 2014, 08:03:24 AM »
Cool, they are not a bad cap  8)

LOL, no noise now? isn't it always the way :)

Offline donberry

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #16 on: October 14, 2014, 02:43:01 PM »
data - I used the obbligato oil filled in a speaker - worked out great.
Well, I now see how the beauty rings come off - they don't. To change the tube sockets I have to basically take off the vast majority of wiring and the sockets are attached to a "pan" that drops down.
What fun,.........

Offline data

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #17 on: October 14, 2014, 10:55:55 PM »
I obviously have little experience with various sockets, as all the ones i have played with you need to unsolder the wires at the tags.

Offline ozcal

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #18 on: October 15, 2014, 07:24:38 PM »
I obviously have little experience with various sockets, as all the ones i have played with you need to unsolder the wires at the tags.
Rebuilding my Ming Da Mc300 pre and YEP! to remove the vanity rings you have to remove the sub plate which involves desoldering a lot of stuff.
What started out as a relatively simple transformer replacement has turned in to a complete rebuild. I have replaced all the standard valve sockets with better quality teflon , gold plated ones.
By the time I am finished the only standard parts will be the transformers , even the case has been enhanced to allow for better mounting of all the Deuland and Jensen caps , regulated heater supplies etc.
Hope it sound excellent as there has been a lot of time and money invested :D
Listening with my ears :)

Offline stevenvalve

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Re: Mingda MC34 -how to remove beauty rings ?
« Reply #19 on: October 15, 2014, 08:00:29 PM »
Rebuilding my Ming Da Mc300 pre and YEP! to remove the vanity rings you have to remove the sub plate which involves desoldering a lot of stuff.
What started out as a relatively simple transformer replacement has turned in to a complete rebuild. I have replaced all the standard valve sockets with better quality teflon , gold plated ones.
By the time I am finished the only standard parts will be the transformers , even the case has been enhanced to allow for better mounting of all the Deuland and Jensen caps , regulated heater supplies etc.
Hope it sound excellent as there has been a lot of time and money invested :D
Ozcal,  That has always been a problem for me with the audio stuff. Like you when I stated replacing the parts inside them and virtually ended up with just the mains and output transformers, even then i was so temped to attack them. What to do to solve this problem.