I think the Mcintosh MC275 is my favorite power amp. There are several revisions. I’m not sure I can pick which is my favorite sound. But I much prefer the simplicity of the banana jack-style speaker terminals of the more modern versions like the MC275-IV. This McIntosh MC275-IV was recently in the shop for repair.
The unit arrived with one of the tubes showing signs of failure. The getter on the failed tube had turned white, a sure sign it had lost its vacuum. The screen grid resistor associated with that tube had opened. Several others associated with biasing the smaller tubes looked stressed. Reworking the various resistors (pictures left and center), and replacing the tubes had the unit running great.
I had the pleasure of listening to this unit with a newly repaired Audio Research LS7 all tube line stage. Think of the LS7 as a simple preamplifier with source selection and volume control, but no tone controls, very simple. The two sounded so good together. An all tube signal path, it just sounds smooth and creamy to me. I’ve been trying to figure out which preamplifier to hang on to in my setup. I currently have this Audio Research LS7. But I also just completed repair on a beautiful McIntosh C712. Both are nice, simple, low profile preamplifiers. It’s going to be difficult to decide which to keep. But, keep your eyes open on our Buy/Sell/Trade page as the other one will be available soon!
If you have a McIntosh MC275-IV, or one of any vintage, that needs repair, be sure to contact Bob the Tech Audio.
