Mcintosh schematics asterisk (*) mark question?

[skynetyt]

Hello!

On Mcintosh Service manual (for example for mc-2155 unit) there are pieces in parts list markers with asterisk mark (*) and also there is a mark:

*Parts marked with an asterisk (*) are replacement parts stocked our Service Department and must be ordered from Mcintosh. These parts must be ordered by part number. Parts not marked my be obtained from electronic parts suppliers.

The question is what is special about hat parts with asterisk? Does Mcintosh conduct some special selection of components to precisely match? Or back in the time that components had not been widely available?


And another question regarding parts list number on shcematics:

C710 066353 ELECT, 100uf, 50V …. (7484)

Where:
C710 – number on schematics
066353 – McIntosh part number
ELECT – electrolytic
100uf, 50V – nominals

And what represent this number --> …. (7484)?

Thank you.

 

[MACKIE1975]

Just match the value of the cap is good.
You can order equivalent part but sometimes certain part you can't get anywhere then McIntosh is the place

 

[skynetyt]

Thank you Mackie for advice!

 

[MACKIE1975]

Mouser or Digikey is the place for caps and certain parts. Don't buy caps on Ebay if you don't have to (could be fake).
Cap List for MC2155 (mostly from Mouser)
http://audiokarma.org/forums/index.php?threads/mcintosh-amplifier-mc2155-caps-list.727638/

 

[skynetyt]

Oh, thanks for the great ready to go spreadsheet! I`ve just composed mine (checked the forum too late). Mainly i am using Mouser for parts. And the filter caps (18000uf 60v) are still available form McIntosh.

 

[MACKIE1975]

There are many discussion on this forum about which type of cap (Nichicon Series).

 

[skynetyt]

From what I have seen, in mc-2155 McIntosh used different brands of caps: Nichicon and Rubycon (also there are some caps without any brand mark on it). I think for the signal path it`s not too bad to use audio grade caps, for the rest - general purpose.
Would be interesting to know, whether, back in the time like 35-40 years ago, term like "Audio Grade Capacitor" had been existed.

 

[MACKIE1975]

McIntosh mainly uses Rubycon.
1. Do It Right
2. Do It Right the first time
3. Never break rule 1.

Take your time, use the best replacement and labor is free.

 

[kevzep]

Yeah agreed, with McIntosh, use the right part, don't get all creative and start looking at exotic and boutique parts on internet discussions and recommendations and whatnot, use the correct replacements and you'll never have an issue..

 

[clinic-audio]

Hello skynetyt

The question is what is special about hat parts with asterisk ? this part is not available on the market but at the factory only

Does Mcintosh conduct some special selection of components : of course ! like many other US manufacturers , some TR are selected for reason of gain or noise . These parameters are not in service manuals , and don't try to make any research on them , you will not be able to reproduce them

to precisely match ? specific components are MC INTOSH part numbers branded . This for a simple reason : to avoid you to use "ordinary component" where a selected one is necessary .

Or back in the time that components had not been widely available? available where ? at factory ? Yes ! but certainly not in the components market

 

[MACKIE1975]

The question is what is special about hat parts with asterisk ? this part is not available on the market but at the factory only

It is not always true.

 

[nbndtrain]

I'm putting together a BOM for my MC2155 as well thanks to MACKIE for sharing the SM. The asterisk for capacitors in this SM is for the non-polar caps, which you should use Nichicon ES series. Signal path should be Nichicon KL, and the rest Nichicon FG. You can use 100v Nichicon PW for the two 47uf 80v caps.