MC2255 with full LED conversion

hadrian333

Active Member
Until now, I lacked the resources to fully convert a MC2255 to LEDs. However with the advent of Northridge Electronics's multidirectional wedge and bayonet LED's, I finally converted a MC2255 completely with LEDs.

The MC2255 uses 4 bayonet type lamps (Ebay item #191021243889) to backlight the front panel. To replace them, just take the front panel assembly off and take out the old bayonet lamps and replace them with the LED's. There's no polarity on the LEDs so you can't put them in incorrectly. No soldering necessary.

To replace the other lamps, take out the upper cover by removing six screws that hold the cover assembly. For The VU meters, it uses 8 multidirectional wedge LED's (Ebay item #201013201462). You need to pry the 2 white clips that hold the display pcb above the VU meters. Then pull up the pcb and take the wedge lamps out of the socket and replace them with LED's. There's no polarity on the LED's so you can't put them in incorrectly. No soldering necessary.

For the display pcb, take out the 2 nuts that hold it to the front panel and remove the jack that attaches it to the display driver pcb. Desolder all lamps on the display pcb and replace them with LED's(Ebay item #191021493534). The upper 5 uses 8V bipin LEDs and the lower 4 uses 15V bipin LEDs. There's no polarity on the LED's so you can't put them in incorrectly. However, be careful when you solder them in place so you that you don't damage the printed circuit and the LEDs by overheating them or applying too much pressure. Reinsert the pcb and attach the connector to the display driver pcb.

With the upper cover and the front panel off, test and make all LED's are working. If they are working fine. put the unit back together! The front panel is way cooler now and way brighter than the original lamps! Cheers!
 

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There seem to be many color variations of the LEDs; warm white, cold white, green. plus different shades (color temp) and brightness levels. Which ones were you satisfied with? I purchased some from another vendor who custom makes them. It took two tries to get them close. They were too cold the first time around. They did not look like an 1866.
 
I've already had a MC7270 and C34V converted to LED's. This week I should be picking up a MC7108 that has recently been converted to LED's. And when my MC2215 arrives I'll also get that converted to LED's.

The MC7270 is definitely a darker blue now - which I prefer. The C34V looks stunning when the lights are turned out.
 
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There seem to be many color variations of the LEDs; warm white, cold white, green. plus different shades (color temp) and brightness levels. Which ones were you satisfied with? I purchased some from another vendor who custom makes them. It took two tries to get them close. They were too cold the first time around. They did not look like an 1866.

These LED's are warm white. The 1866 like all inicandescent lamps are more orange than white in color. These LED's have a colored filter as you can see from the photo to simulate the color of an incandescent lamp. The bigger issue with LEDs are that they are very directional and it's very difficult to get a omnidirectional brightness like the incandescent lamps. The new omnidirectional LEDs used for bayonet and wedge type application overcame that by having 4 LED's surround the lamp and one LED firing straight above it. the bayonet LEDs are diffused across the front panel so the side firiing LEDs solved that problem perfectly. As for the wedge type LED, the side firing LED's backlit the meters perfectly to achieve omnidirectional brightness. Because the bipin LEDs are replacing unidirectional lamps, it works perfectly for function indicators.
 
Thanks for posting on this topic. I've not seen a meter compartment/lamp pcb photo of the 2255 before, and have the same idea for updating the 2205. Hope this isn't too much like hijacking your thread.

The 2205 was updated over a three year period starting in summer 2009. What was left unfinished was "new glass" and LED conversion. I took the lamp housing out that year and replaced the foam strips..

MC2205_Love_flashing_fasten.jpg



It was noted several times in this forum that, IMHO the 2205 front compartment runs TOO HOT when the amp is FULLY inside the Mc cabinet. A work-around is to pull the 2205 out until the VENTS cleared the cabinet!

2205_detents_vents.jpg



For better stability with 2205 slid forward out of the case, I repositioned the front cabinet feed.

L54_cabinet_after_17.jpg



In the pic below you can see the EIGHT bayonet lamps across the top of the meter housing.

MC2205_Love_poweron.jpg



I'm proposing to fabricate or purchase TWO PCBs like in your picture where LEDs can be soldered. It would be an easy and fun conversion.


That's the plan.. the final cosmetic (and thermal) update!!


-Gregory
 
I'm sure some will view this as a stupid question, but I have to ask. Why the attraction to converting to LED? Is there a particular benefit or is it purely an aesthetic decision?

I see the Marantz folks have been doing this with their 22xx series receivers for a while now. It certainly changes the look considerably.
 
I'm sure some will view this as a stupid question, but I have to ask. Why the attraction to converting to LED? Is there a particular benefit or is it purely an aesthetic decision?

Well.. as we've been discussing for years, it for reliability and cooler operation. Above I mention the HEAT issue yet another time.

Cheers,


-Gregory
 
Well.. as we've been discussing for years, it for reliability and cooler operation. Above I mention the HEAT issue yet another time.

Cheers,


-Gregory
Completely agree. Also an aesthetic decision (for me). I've taken pre LED conversion pics of my MC2155, and will take post conversion pics when the job is complete.
 
I see. But don't these mods effect resale value?

Depends on if you're planning to sell. The mod for the 2205 only involves drilling and tapping four holes in the top of the lamp housing. The EIGHT original lamps pop-out of their holes, and if you simply unsolder the supply line, then all come out in a 'string' of lamps and sockets. IOW the mod could easily be undone.


-Gregory
 
Completely agree. Also an aesthetic decision (for me). I've taken pre LED conversion pics of my MC2155, and will take post conversion pics when the job is complete.

Please send me the part list and place of order so I can upgrade my MC2155
thanks
 
Hi Mackie, I had a local tech do my MC2155. Not sure of the parts they used, though I'll be back home in a couple of days and can check my receipt to see if they listed the parts.
 
LEDs unavailable?

The ebay# 191021493534 is no longer available. Any suggestions?

FYI, McIntosh wants $111 for their replacement bulbs and have no instructions.

Any detailed instructions for replacing the bulbs out there?
 
these should also work nicely, I just got them in for my own use and they are very affordable. And they are the same LED in a housing that can be cut down or pulled off entirely leaving just LED and drop resistors. The base can be snipped off to shorten length and just place led back into the plastic holder

item #221021094472 $4.15 shipped total. for 10 pieces that's 41.5 cents each :thmbsp:


Don't pay money needlessly for something a child could adapt.

#190649138195 are way over priced for the exact same LED indicator and drop resistor setup...$4.95 plus $6.00 shipping EACH!!!!.........:no::no::no:
 
these should also work nicely, I just got them in for my own use and they are very affordable. And they are the same LED in a housing that can be cut down or pulled off entirely leaving just LED and drop resistors. The base can be snipped off to shorten length and just place led back into the plastic holder

item #221021094472 $4.15 shipped total. for 10 pieces that's 41.5 cents each :thmbsp:


Don't pay money needlessly for something a child could adapt.

#190649138195 are way over priced for the exact same LED indicator and drop resistor setup...$4.95 plus $6.00 shipping EACH!!!!.........:no::no::no:

I'd be interested in seeing how you eventually use these.
 
I've already had a MC7270 and C34V converted to LED's. This week I should be picking up a MC7108 that has recently been converted to LED's. And when my MC2215 arrives I'll also get that converted to LED's.

The MC7270 is definitely a darker blue now - which I prefer. The C34V looks stunning when the lights are turned out.

If the MC7108 is like my MC7106 ( they were related products, same generation) then you will have to desolder/re-solder to change out your bulbs.
Are the same LEDs suitable for soldering?

Postscipt: Whoops! Just noticed that you said it was already done by someone else.
 
I'm sure some will view this as a stupid question, but I have to ask. Why the attraction to converting to LED? Is there a particular benefit or is it purely an aesthetic decision?

I see the Marantz folks have been doing this with their 22xx series receivers for a while now. It certainly changes the look considerably.

Because I replaced the green "normal" lights on my MC2200 five years ago and one of them is already burned out. It was easy enough to replace the bulbs but wrestling that 82 pound beast out of the rack and muscling it onto the workbench is no fun.
 
I'd be interested in seeing how you eventually use these.



Easy, with a big smile and a fatter wallet lol lol lol.. They are just LEDs with standard 12 volt drop resistors inside of the plastic housing. Just lift the two wires passing thru the bottom of the plastic housing, and gently lift out the LED assembly.

Then cut off the plastic housing to any length you feel you need with snipes. Then place the LED assembly back into the plastic housing, and insert wire leads into circuit board and solder just like the $10.00 ones.... and smile all the way to the bank...

A LED setup with drop resistors for 12 volts, is exactly what the $10.00 each item is. The LEDs are a standard off the shelf item with standard voltage drop so the only thing special for that $10.00 is that little plastic case and those golden pins the $10.00 one uses, and you don't need golden pins as I found out on the2205 I recently did....

Both LEDs work off 12 volts so except for that fancy housing the $10.00 ones have well there just isn't enough difference to qualify the $10.51 cost difference IMHO... Heck with what Mac parts cost anyway, isn't it nice to save a 60 or 70 bucks on some LEDs....:thmbsp:

I also picked up some aluminum LED bar LEDs that will fit nicely in top or bottom or directly epoxied to the back of the meter housing for the 2205. Since they are bonded to aluminum strips they can be epoxy glued into place anyway you want inside the metal housing.
Now these come in 12 volt only and the standard light bulbs are 5.6 volts AC, but that same AC feeds the -12 volt rectifier voltage doubler on the power supply board just behind the meters so you got -12 volts there off the same AC source so this panel meter mod also works nicely on -12 volts used to drive the front panel leds off the same AC supply and it will never draw what those light bulbs did so current wise your good to go...and cool lighting will protect those expensive fancy glass face plates I hear everyone swapping because of bubbling and heat cracking of the paint used to make them...

< the minus 12 is on those big capacitors on the power board just behind the meters, the two diodes form a voltage doubling rectifier so that 5.6 AC get turned into -12 across those two big caps everyone replaces, and that -12 drives the power / clip LEDs on the face anyway...so Your all good >>>>>

I put some thought into this mod before buying into it, I hope my head scratching will help all of you save money and achieve perfect LED back lighting that will most likely out live us all and for cheap...
I looked into the so called LED upgrade kits selling for $340.00 and just shook my head at the margins those people are making. Now don't get me wrong they make nice kits with circuit boards and the like. But flat 2 sided PC board costs 7 cents per square inch to make, not $300.00....

Its gets tiring and boring to see that everything for a Mac amp costs too much to make common sense, especially something as simple as LED back lighting which has absolutely no effect on MAC SQ,,, just your poor pocket book from unscrupulous people.... Not everything MAC needs to break the bank....:thmbsp:
 
I'm sure some will view this as a stupid question, but I have to ask. Why the attraction to converting to LED? Is there a particular benefit or is it purely an aesthetic decision?

In many cases, it's simply because you can no longer get some of the bizarro bulbs used in days of old. I'm going thru that right now with a Sansui QRX9001.

That said, I still prefer the look of incandescent and am planning to change out to fuse lamps.

Heat was also mentioned ...

mc2205-meters.jpg


You can see the brown spots on the color gel. Fortunately the gel sheets are easy enough to replace - hard part is finding a good match for the original Big Mac Blue.
 
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