MC 2125 meters dark in center

Jack Fedor

New Member
I could use some help with the meters in my 2125 they are brownish in the center when they are on.I have replaced the lamps with blue led's but still the same.Is there a paper in between the lamps and the rear of the meters and how do I replace them
 
Very very carefully......the lamp housing will fall apart if you fuss with them in almost all cases. Years ago I believe I posted pics of Mc2125 lamp cases in dozens of pieces.

That said there are 3 gels that make up the color for the meters located inside the light boxes. The clearest least tinted ones turn brown, they are usually between the two colored ones which leads me to believe it is not caused by heat but by UV.
 
mc2205-meters.jpg


Oh, wait ... were you talkin' to me? <G>

Discolored gels are a fairly common problem though ...
 
Hello

using led is understandable but I will not recommend it . Your problem is coming from the gel , it is burned and turn to brown ...
Regarding heat in the light boxes all problem disapear with manufacturing them in the right material

MC2125-and-MC2155-meter-housing.JPG MC2125-MC2155-meter-housing-new.JPG MC2125-MC2155-meter-housing-new-inside-view.JPG MC2125-meter-rear-view.JPG
 
I need a couple of the meter cases also, where can you get them. I am just now getting into McIntosh, bought a MC2125 at a very good price at a garage sale. And of course I then had to buy a C38 to go with it. I was replacing bulbs on the 2125 and noticed that it has no filters inside the meter, just a piece of blue tinted glass in the front. Any help would be great. Also notice a couple of diodes where cooked on the meter board so I have ordered a service manual.
 
While you're in there, be sure and clean the wire terminals at the back. Well known for causing intermittent problems,

meter-posts.jpg
 
When you replace the housings use lamps with a lower current draw or think about switching to LED. When I bought my 2505 pre-owned at the first Mac clinics Davie Obrien installed lamps with a lower current draw for me. They lasted almost 25 years with the unit on at least 5 days a week.
 
Thanks for the tip. Sounds like I need to use those bulbs. Do you happen to know a part number or link for these lower current bulbs?

I may as well get new gel/gels while I’m at this too. Anyone know the color combos used to get the blue/green factory look? Mine are NOT burned out brownish in color, but have faded to a pale blue. These are what I am looking at...
https://www.parts-express.com/cat/gel-filter-sheets/1015
I’m thinking three of the #118’s would do the trick. If anyone has done this before with ideal results, I’d love some advice.

There is also these, which look great. Hmmm...
https://www.adorama.com/le132s.html?gclid=EAIaIQobChMI1dTWrPz94gIVjI-zCh1PZA3SEAQYBSABEgJlPfD_BwE
 
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When I rebuilt a pair of Mc2125 meter with the last of Mac parts MC2155 meters I got the help of my two photographer neighbors to find the correct gels to get the now LED lit meters to match a MC7270.

I also saved the old three gels somewhere......I have the universal gel numbers saved somewhere but seem to remember one had the name sea green??

You have to decide if you want them to match Mac's orginal color with new LEDs or just any old blue.
 
I’d love to know the original universal gel numbers. My goal is to bring the meters back to their original color. I’d go LED’s, but I just don’t know which ones to get. I’ve heard stories of people buying the wrong ones, having to solder, being too bright, etc. I’m open to suggestions, just need the right current draw led’s or bulbs. One member above suggested bulbs with lower current draw for less heat. I like this idea.
 
Because of the fragility of the meter boxes of the MC2125 and Mc2155 i believe they are worth the extra, careful, delicate, effort to convert them to the use of LEDs.

Heat captured within the boxes led to DOB going to some extreme measures to vent them back during the clinic days.

Since they use the "fuse" style lamps the measures taken to restore them to the correct look are unique to them and have little relevance to the other units that used bayonet or flange type bases. The radiation patterns are just plain different between the 3 styles.
 
Oh yes, the original meter boxes on my MC2125 have became so fragile. When trying to change the factory bulbs the other day, the boxes were cracking badly. So I've contacted member "clinic-audio" about some new meter boxes. Note the pictures at the beginning of this thread...those look very nice, and I like how they are vented well. He's supposed to get back with me shortly. You think I should still convert to LED's when using the newer style, vented boxes? If so, what LED's would you recommend to maintain the factory look of the meters?

The radiation pattern you mentioned is what also makes this a little difficult. Part of me just wants to send the amp to Audio Classics and have them restore the meters to the factory look. The amp is all original, purchased from the original owner and still sounds great. Only issue is the meter color faded to pale blue and a couple burned out meter bulbs. I hate to spend all that $$ shipping just for the washed out meters and blown bulbs, although I do have the factory box.
 
I was looking for this box of meter remnents yesterday. After I get moved I will have two Mc2125s that will need their meter lighting addressed. The light boxes will hopefully be in better shape than these were.

However since to change the light gels means disassembling the meters you must prepare for the worse case situation. Even though I have saved meter movements I do not even want to contemplate screwing up a meter mechanism.

IMG_20190623_115216882.jpg
 
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