MC2155 - Complete restore?

[Jon_J]

I think I have all threads pertaining to the MC2155 bookmarked after reading the McIntosh forum for over a month.
I sent my MC2155 off to Terry a few days after below post, (with help from "clinic_audio" diagnosing my LDR malfunction).
"MC2155 - no Right Channel"
http://www.audiokarma.org/forums/showthread.php?t=656890

While waiting for my MC2155, I have also re-foamed my speakers with help from the friendly guys in the "Speakers" forum.
"Can anyone identify this woofer?"
http://www.audiokarma.org/forums/showthread.php?t=658105

And I also found a broken wire to the voice coil in one of my midranges. It took me quite some time to repair this.
My first try didn't work because I used a strand of stranded wire to "patch" the break.
This made the speaker "buzzzz" and "rattle" at certain frequencies.
I removed the "patch" and "liberated" some slack in the original wire that was glued down and made the repair.
It is repaired now.

I'm curious if anyone has posted or shown a Re-cap or complete rebuild of a MC2155?

I know the MC2155 is very similar to the MC2255 and (MC2150. MC2250).
I also removed the knobs and faceplate from my MC2155 before I sent it to Terry and have found the deteriorated foam behind the faceplate.
I have purchased some weatherstrip, but only found quarter inch by three eighths inch dimension.
A post by "Gregory" shows a three sixteenths inch dimension. in some of the weatherstrip he purchased.
One more thing. I found some very good pictures of the backside of the faceplate for the C28 with all the details.
And a picture of the front of the C28 with faceplate removed.
Are there any pictures of a MC2155 faceplate back and corresponding front of MC2155 with faceplate removed?
I attached the 2 pics I have of the C28 faceplate.

Thank you,
Jon

 

[Jon_J]

MC2155 Faceplate Back pics

I couldn't find any online pics for the MC2155 Faceplate pictures of the backside.
I set up a strong light to avoid flash and took some pics of my MC2155 Faceplate backside. (First pic)
The day after I removed my Faceplate, I found a small rectangular piece of plastic on the floor.
It's flat black on one side and gloss black on the other side. (Second pic)

Did this fall out of my MC2155 as I was removing the Faceplate?
Does anyone recognize that small piece?


By the way, I found a link to some great pics on a Japanese site for the MC2125.
http://topseller.jp/store/member/amp8/tr-amp/foreign/mcintosh/mc2125.htm
I also found a similar Japanese site for the C28 Preamplifier. I need to find the url. I'll post it if I can find it.

Thank you,
Jon

 

[Matte Grey]

Possibly for the "System Test Digital Readout Display".

 

[Jon_J]

Possibly for the "System Test Digital Readout Display".

I checked my MC2155 Faceplate backside closely under a lighted magnifier and didn't find any place where that piece would go.
I also (during the same evening) removed the faceplate on my C28.
I'll need to check my C28 when I remove the faceplate next time when I ship it to Terry after my MC2155 arrives home.
When I purchased my MC2155, I got the owner's manual and service schematics, (2 map fold booklets).
The schematics are actually for the early MC2155 and mine is somewhere in the middle of the serial number series.
According to my output driver boards I should have the 2nd set of schematics.
These were 3 map fold booklets. The MC2155 schematics are nowhere to be found online.
Today I found a set of schematics for the MC2150 and it is a PDF with 32 full pages.
It also has pictorials of the boards and top of the amplifier and parts numbers and references, which my printed copies don't have.
It also has the same driver board numbers illustrated as my MC2155 has, not the older ones as in my hard copy.
I printed the 32 pages, but I'll need to print them all again at a slightly smaller resolution.
My printer doesn't print all the way to the edge of the paper and the margins and header/footer caused a lot of missing text/etc.
My schematics for the MC2155 page count is only 24 pages with one blank page.
So I have 9 pages less than the MC2150, which has no meters and associated circuitry.
I inquired in the Digital Data forum here at AudioKarma about uploading the MC2150 schematics PDF.
I haven't gotten an answer yet.
It's not available in the Digital Documents database.
EDIT:
I just emailed the MC2150 schematics to the correct address for the AK database.

Thank You,
Jon

 

[Jon_J]

If anyone is interested, the MC2150 schematics are now in the database.
It's shown on page 6 under McIntosh Amplifiers.
For some reason it is out of sequence of alphabetical order and is not next to the MC2120 or MC2155.

Jon