"Bob Simon" wrote in message
...
On Wed, 14 May 2008 10:56:00 -0700 (PDT), wrote:
On May 14, 1:00 pm, Bob Simon wrote:
I have a McIntosh 2100 that was performance certified in 1976 at a
clinic. Now it needs service - one of the channels intermittently
drops.
Do they still have those free clinics?
Been a while since I heard of one but you can find people to service
them. The free clinic wouldn't have fixed it anyway.
There's a guy in town who has a good reputation. A few months ago he
replaced some components in my NAD preamp/tuner and it cost around
$125. This was more than I expected but I haven't paid for electronic
service for 10 years so I really don't know what this work should cost
now.
Do you think there may be an advantage to sending it to McIntosh for
factory service? As I understand it, the transistors have to be
matched.
$125 for anything over and above a quick cleaning is cheap. Shops generally
are charging $50-$75 for a diagnosis/estimate these days.
If you've got the cash, sending it to the factory for servicing GENERALLY
guarantees a certain quality of service and availability of parts which your
around-town guy might (or might not) be lacking. We've all heard horror
stories though, so it's not a lock on perfect results. Sending it back to
the manufacturer almost always involves a lengthy period of time too. If
you have a knowledgeable, competent technician I don't think you're going to
do any better at the factory.
You can buy output and driver transistors in matched sets, a PNP mated with
an NPN with similar gain characteristics. You'd only ever need to replace a
transistor if it was bad, it's not a preventative maintenance item to
replace any.
If your channel cuts out randomly, it COULD be a transistor, but it's more
likely a cold solder joint or dirty switch in a piece of vintage gear.
Dave