Mc2155 Output Driver Help
- Thread starter funkenaround
- Start date
It is a shame to see such a fine amp being "repaired" in such a hap hazard fashion.
Last I checked for a clients MC 2155, Mac still has the central semi sourced predrivers....not cheap but correct lead layout and considerably more matched than those of 25 years ago.
I am still running my mc2125 and mc2250 with more modern substitutes expecting the central semis to someday be gone.
Last I checked for a clients MC 2155, Mac still has the central semi sourced predrivers....not cheap but correct lead layout and considerably more matched than those of 25 years ago.
I am still running my mc2125 and mc2250 with more modern substitutes expecting the central semis to someday be gone.
funkenaround
Active Member
the spec is same .15 ohm 5 watt NO ! that's your reason of your problem ! this is not a rocket science but your rocket will not work !
how I have purchased the wrong resistors, I am going exact by the spec which is stamped directly on the resistor, look below and see, I buy exactly as is required and you say they are no good? please explain
below is what I purchased
MILLS-64396
0.15R / 5 Watt, MRA5, 1%, 20ppm, Axial Leads, Non Inductive, Wirewound, Each
$3.95 $3.95 pcX USD Price
where have I erred?
how I have purchased the wrong resistors, I am going exact by the spec which is stamped directly on the resistor, look below and see, I buy exactly as is required and you say they are no good? please explain
below is what I purchased
MILLS-64396
0.15R / 5 Watt, MRA5, 1%, 20ppm, Axial Leads, Non Inductive, Wirewound, Each
$3.95 $3.95 pcX USD Price
where have I erred?
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kevzep
Its all about the Music
All you need to do is follow the instructions, all this advice for free can save you $$$ if you are methodical and patient.
How lucky to be able to get such advanced help, but then you get upset with us? The reason we are like this is because it is so easy if you follow the instructions especially from clinic-audio, he has over 35yrs experience repairing McIntosh.
You don't follow the instructions and now you pay the price.
None of us have to do this, we all give our own free time to help keep the McIntosh legend alive, so perhaps following all this free professional advice is in your best interests is it not?
Its not just the resistors, its your whole approach to the project. As I said from the beginning, solid state amplifiers are not as forgiving as tube amps, things happen very fast, transistors are current devices, and when something is wrong they will destroy themselves faster than you or any fuse can react to save them.
You need to go right back to the beginning and start again, carefully and methodically.
funkenaround
Active Member
mcintosh
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funkenaround
Active Member
mcintosh
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funkenaround
Active Member
funkenaround
Active Member
funkenaround
Active Member
It's alive
funkenaround
Active Member
happy to report that I've been thoroughly enjoying this fine piece
so much so that I may even wear it out, wait its not a tube amp...lol
all of the re assembly issues that I experienced were due to a transistor installation f'up...installed in the reverse....happens I guess
truly, I can't stop listening......paired with my Mcinstosh MX110, superb!
am I surprised, yes, allot, didn`t think I`d enjoy it as did I my tube amps
think it may be time to let go of some tube gear
many many thanks to all those who help my endeavor and a special thanks to Patrice for his involvement
I`ve been on the hunt for more broken Solid State gear to bring back to life
its not rocket science, just a task of a patient hand
so much so that I may even wear it out, wait its not a tube amp...lol
all of the re assembly issues that I experienced were due to a transistor installation f'up...installed in the reverse....happens I guess
truly, I can't stop listening......paired with my Mcinstosh MX110, superb!
am I surprised, yes, allot, didn`t think I`d enjoy it as did I my tube amps
think it may be time to let go of some tube gear
many many thanks to all those who help my endeavor and a special thanks to Patrice for his involvement
I`ve been on the hunt for more broken Solid State gear to bring back to life
its not rocket science, just a task of a patient hand
kevzep
Its all about the Music
Good to see you are enjoying your amplifier.......:thmbsp:
Once the McIntosh bug bites, its all over, there's no escape....
clinic-audio
all on YAMAHA untill 1990
Hello !
many many thanks to all those who help my endeavor and a special thanks to Patrice for his involvement
Thank you ! not really easy to see (from here) what you had in front of you but we did it !
I can't give up when somebody is asking help on a unit like this one !
you deserve to use it for a long time now !
enjoy !
Patrice :thmbsp:
many many thanks to all those who help my endeavor and a special thanks to Patrice for his involvement
Thank you ! not really easy to see (from here) what you had in front of you but we did it !
I can't give up when somebody is asking help on a unit like this one !
you deserve to use it for a long time now !
enjoy !
Patrice :thmbsp:
MACKIE1975
Super Member
Very interested thread and a very patient helper.
My background is a semiconductor fabricator. Here is my take:
1. Make sure buy original part for high end equipment.
In the (our) chip making (fabrication) business, even the same chip on the same batch, wafer will have different results (specification). The chips (semiconductor) will be sorted accordingly. Usually the chip that pass the tight spec and tolerance will be sent out high end manufacturers like McIntosh or military use. Low end pass (specification) chip will be sent out for general use (application). Of course, certain diode or chip will only need to pass one specification and one specification only. These chips usually are easy to make and cheap.
2. If you drive a Benz I don't think you want to go to Auto Zone and get a transmission from them and most of of the time the part is not available.
When you go high end expect to pay or just get a Sony or a Corolla
losgorniacos
New Member
Hi i have a similar problem with left ch. of mc2250. Phones working but speaker stopped. The optocouplers 6500 and 6000 looks fried. Is good idea to change them only or maybe the reason is in different place iven if they not working. Appreciate for your advice.
clinic-audio
all on YAMAHA untill 1990
Hello losgorniacos
I already answered to this kind of questions sometime ago .
You said : The optocouplers 6500 and 6000 looks fried.
No , I don't think so , they are defect but not fried ! a perfect substitute for 144159 (CLM6500) is VTL5C9 (I don't remember the MCINTOSH part number)
If you want to be sure that your trouble is coming from there , make a short (amplifier on, audio signal on ) between pin 3 & 4 and sound is coming back you found your trouble source !
don't do any short between pin 1 & 2 !!
I already answered to this kind of questions sometime ago .
You said : The optocouplers 6500 and 6000 looks fried.
No , I don't think so , they are defect but not fried ! a perfect substitute for 144159 (CLM6500) is VTL5C9 (I don't remember the MCINTOSH part number)
If you want to be sure that your trouble is coming from there , make a short (amplifier on, audio signal on ) between pin 3 & 4 and sound is coming back you found your trouble source !
don't do any short between pin 1 & 2 !!