TFM-45 Observations (looking for feedback)

Take this with a grain of salt, but I seem to recall the power-off thump of the 45 was addressed with a revision of some kind, or a service bulletin, and that it was not a harmful thing but merely a matter of preference and satisfaction.

I just put a TFM 45 on my 1C's and there is the power up hum (brief) but NOT thru the speaks. No power off thump,and it does a nice job of driving the Polks,,If you get an opportunity,try the 1C's with a tube amp of 40 watts or so,I thinkk that you will be pleasantly surprised. Good luck.

Some of what you are describing sounds similar to my observations with the TFM-45, except for the thumping. My 45 seems to make a faint hum/buzz and it has done so since new. I got an answer to this about 10-12 years ago but cannot remember what the cause is(sorry). My TFM-75 does not have any issues like that at all. If you ever find one of these in good condition buy it fast!

Back to the hum I believe that it is the power transformer that you are hearing when you first power up.