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Mike Coon[_2_]

In article ,
says...

On Sunday, December 6, 2020 at 7:49:16 AM UTC-5, Peter W. wrote:
A few things:
a) McIntosh winds their own transformers.
b) McIntosh has been in business for many years, and through many ups and downs.
c) Meaning that their management at least has some basic business intelligence.
d) Suggesting that the transformers they make/made are not unique to each individual component.
e) Suggesting that it is quite likely that they may have that transformer available.

It's not. I emailed McIntosh asking about a replacement, or a suggested "universal" replacement that might physically fit the tight chassis that could be installed with some circuit modification, or perhaps a suggestion of a rewinder they were familiar with or might even have used. I received a very quick and terse (if not polite) email from McIntosh Friday that answered all three of my questions with a simple "I?m sorry there are no options for this transformer."
Boom.

The MX110Z is very very tight. There's literally no room for a transformer that would allow the case to fit if the replacement was any bigger even by a small percentage. This particular piece is known to have a power transformer that runs *very* hot even when everything is otherwise normal. The transformer has a B+ winding and three filament windings and is also supposed to be more heavily shielded than the average bear.

I could probably find a way of cobbling a different power transformer and another smaller filament transformer somewhere else on the chassis (or just build a remote XFR box with an umbilical) but I don't want to reinvent the wheel at this point, plus I feel most of the *value* of this piece is in the originality of it, not to mention Mc's careful design of the filament circuit and wire routing for hum mitigation. Add to that the fact that two of the four selenium
rectifiers under the deck relieved themselves of tiny solder balls (which happens when the 1A slow blow is replaced with a 20A fuse), and all cans are original and probably need to be restuffed, and it just seems like a project not worth the time at this point.

I returned the tuner/pre to the owner yesterday with the suggestion of either putting it on ebay, where this model in non working condition will bring $400 at least, or keep checking ebay and finding one in poor cosmetic condition with a good XFR in it.

Sounds like a mistake I made ca. 1960 when I built a valve oscilloscope
(which I still have; sentimentality!). I built it around the mains
transformer whichwas between two bulkheads and gave the whole thing
rigidity. So when it failed rewinding it was the only solution. And
building a coil-winder out of Meccano was my solution to that...