MC2255 with full LED conversion

[lbcgav]

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:

The 7381 lamps are 6V and the 7382's are 14V. Do you need to do any modification to the 12V LED to use them in these applications?

 

[1moreamp]

The 7381 lamps are 6V and the 7382's are 14V. Do you need to do any modification to the 12V LED to use them in these applications?

Nope leds run on just about anything above three volts. Plus those expensive ones are 12 volt per their markings, and they apparently work.
And even if the brightness wasn't what you want, the drop resistor value can be decreased to accommodate any brightness issues you need for a few cents more each resistors are on sale at radio shack to lower forward voltage drop issues..on the 2205 the drive circuitry uses -12 supply to most everything on that lamp driver board, taking into account for silicon transistor junction voltage drop which is current draw proportional if any changes are needed they will be minor resistor value drops only, nothing more...

For a ten buck savings each I can rethink this one all day long lol...LEDs are cheap, and even cheaper now made in China, so they should not be costing like the dickens to use in anything... I see price gouging on anything Mac related... LEDs should not be costing what I see some people asking...

 

[smartin53]

LEDs are nice because they definitely lower the heat issue, but also sometimes bring you closer to the stock value without worrying about color gels or so on.

I've encountered both the positive and negative. In my MA6100 I could never get the proper lighting distribution using green or white LEDs. The end result was that the LED areas were too bright but the outlying areas were dim.

On my MAC1700 and more recently my MX110 tho, green LEDs along with the faded gel filters got me to exactly what I wanted. The backlighting was bright but uniform without overpowering. When viewed alongside a stock lighted MX113 the MX110 looks almost the same.

 

[lbcgav]

Those look fantastic. My MR74's white numbering is barely visible. I'd like to try LEDs on it. Could I use a green filter over white LEDs to achieve the same effect?

LEDs are nice because they definitely lower the heat issue, but also sometimes bring you closer to the stock value without worrying about color gels or so on.

I've encountered both the positive and negative. In my MA6100 I could never get the proper lighting distribution using green or white LEDs. The end result was that the LED areas were too bright but the outlying areas were dim.

On my MAC1700 and more recently my MX110 tho, green LEDs along with the faded gel filters got me to exactly what I wanted. The backlighting was bright but uniform without overpowering. When viewed alongside a stock lighted MX113 the MX110 looks almost the same.

 

[smartin53]

Those look fantastic. My MR74's white numbering is barely visible. I'd like to try LEDs on it. Could I use a green filter over white LEDs to achieve the same effect?

Possibly, but it depends on how good the green filter is. Some can be overpowered by white LEDs. My recommendation is to just get the color LED you are aiming for color wise. I wanted that McIntosh green so green LEDs did the best job.

 

[sKiZo]

Worth mentioning (or repeating if I just missed it) a lot of faceplates use phosphors in the inks used for dial markings and need a certain amount of "excitement" from the light source to pop out as intended. Been doing a bit of reading on my QRX 9001, and apparently standard LEDs won't cut it - super brights are required ...

I suppose super super brights would be an interesting experiment, but might want to put a towel under the receiver in case they get TOO excited ...

 

[1moreamp]

Bright spots will need a diffuser panel of plastic added < milky translucent plastic is a fair diffuser> Again some experimentation might be in order but Tap plastics might be a start to look for translucent plastic to use as diffusers.

Plus the LED bars come in several different layouts as to the positioning of the LEDs and what type of LED and their built in diffusers. My thinking is reverse placement of the LED bars against the back of the meters facing towards the back metal cover will also help to spread out the bright spots somewhat.

Reflected light tends to spread out better then direct lighting most of the time so, a little patience's and some back and forth testing and it all can be sorted IMHO..Plus the cooling effect on that glass faceplate has to have positive benefits. Oh and no more burnt gels also...woo-hoo!
Incandescent lamps are so energy inefficient for the most part the heat issue is a real plus plus for LEDs.

Plus I did a LED Marantz a few years back and the difference was absolutely stunning. The whole face took on a irritated glow of UV almost.< I was worried I would have to pull it all out > The owner felt it was better then new and just a joy to look at. He even felt it had a clarity added with the unique glow it had. He actually cash tipped me for the LED face highlights... So its not all Debbie downer about doing LEDs, a lot of folks feel its a vast improvement,,, Plus they have that very long lifespan thing just making their day knowing its done for the next 10 years or forever....

Heck I bet most of you are watching LED back-light TV's and monitors right now.... and loving it knowing your new TV isn't going into the dump for bad back-lighting like all those CFL TVs of yesteryear... I can not tell you how many CFL power supplies I have repaired, and forget replacing the tubes its cheaper to buy a new screen...

LEDs :thmbsp: definitely worth the efforts, even with the perfectionist color match thing to deal with. In the very long run you will be glad its done for the rest of your life...

 

[Rich Andrews]

What will really frost your flakes is when you realize that some of the blue-green tint is actually caused by the "clear" glass on some of the vintage units like the MR67 and C22. If you look closely at the edge of the glass, you can see the blue-green tint. You can't see it until you look at the edge. White leds that have a blue tint to it makes a C22 and MR67 really pop visually.

 

[monkboughtlunch]

LEDs are nice because they definitely lower the heat issue, but also sometimes bring you closer to the stock value without worrying about color gels or so on.

I've encountered both the positive and negative. In my MA6100 I could never get the proper lighting distribution using green or white LEDs. The end result was that the LED areas were too bright but the outlying areas were dim.

On my MAC1700 and more recently my MX110 tho, green LEDs along with the faded gel filters got me to exactly what I wanted. The backlighting was bright but uniform without overpowering. When viewed alongside a stock lighted MX113 the MX110 looks almost the same.

What brand LEDs did you use for MX110 (and what size and voltage)?