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McIntosh Mods - Sticky?

Rich Andrews

Rich Andrews

Well-Known Member
I know there is a sticky for hints and kinks which is repair orientated. How about one for McIntosh mods? Terry and I both have some mods that do make a quantifiable and demonstrable difference. I am sure there are others than have some mods that are not published.

Is this something that people would like to see?
 
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Mods?....LED kits?

I know AC's offers a few. Do you and Terry? I have a mc 7100 that could use one.
 
Definitely interested. One I can think of is swapping out op amps on McIntosh CD Players to improve them. I've socketed all of the opamps that I can on mine for eventual tinkering (assuming I ever figure out what is wrong with it).
 
LED kits?

LED lighting is something that can be done by almost anyone. All that is needed for festoon bulb replacement is a good soldering iron, some brass tubing, a razor saw or similar, and some 3 mm flat-top white (not warm white) LEDs. The brass tubing was purchased at a hobby store for $4.00 for two 12" lengths and the LEDs cost $7 per hundred shipped.

In terms of figuring out how many leds are needed in series, I use the following formula.

Source voltage (must be measured) divided by 2.5 = total number of LEDS required.

In the case of the C22, the source voltage is about 26 volts. 26 / 2.5 = 10.4 or 10 LEDS. If a really bright light is desired the # of LEDS could be reduced which means each led will be at or near it's upper limit which is usually 3.0 -3.2 volts for white LEDs. In this case the number of LEDs in series would be 8.

In the case of a MR67, the source voltage is 6.3 volts. 6.3/2.5 = 2.52 or 3 leds. Three leds in series was too dim for me so I used two in series.

I thought about changing the Powerguard lights on my MC2500 amps to LEDs when I had each on the bench for cleaning and maintenance, but decided to wait until they burned out again.
 
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A mods sticky would be good. Not just LED's and Op-amps. Capacitor/resistor choices, tuner mods and many others would be welcome.
 
Rich Andrews said:
Is this something that people would like to see?
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A MOD sticky would be nice.

I have been trying to get infomation on Transistors used on MAC 1900..

Boy...This is being held to the chest...I have a MAC 1900 Recap thread and in need of PreAmp Board Transistors. Has to be Mouser part #.

I also contacted Terry(he have restored 1 of my 1900's last month)...Since he has Orig. Transistors he did not put together a Sub list.:tears:

I also contacted audioclassics.com...They have no Transistors for this but will talk with the Service Dept. to see on finding out Sub Parts. From the looks on the MAC 1900...I am ready to say...Stay away from this model. Luckily I will be getting a MAC 4100 next week..I nice CL buy. Just maybe will put Both 1900's on the Sell Board.
 
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Nothing close to the chest about it....others have done their own homework, posted their possible subs, and those choices have been discussed as decent substitutions in the past in various threads.....
 
c_dk said:
Nothing close to the chest about it....others have done their own homework, posted their possible subs, and those choices have been discussed as decent substitutions in the past in various threads.....
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OK...I am going to look again..Thanks
 
c_dk said:
Nothing close to the chest about it....others have done their own homework, posted their possible subs, and those choices have been discussed as decent substitutions in the past in various threads.....
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OK...I did find some info in this....Lot's of digging...I posted the findings in my 1900 Thread.

This stuff does need to be organized...it just the IT in me.
 
CohibaJoe said:
OK...I did find some info in this....Lot's of digging...I posted the findings in my 1900 Thread.

This stuff does need to be organized...it just the IT in me.
Click to expand...
1. Get a copy of the McIntosh transistor sub booklet. Lots of great info there.

2. Once you find a commercial number for your item, go to the Onsemi web site and check for availability or check for a sub, or just type the id into the Mouser search box.

3. If all else fails, check in here and see what you can find out.

There are so many transistors in each unit that a comprehensive list just isn't practical.

Murray
 
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