Sony XM-120 (Very old school) for the new school

[Dr Zeus]

I really dont know how old this amp is, but let me say, its OLD; like Alpine 3545 era. This amp is rated at 60w+60w (60x2). The neatest thing I saw on the outside of this amp is it's power rating is graphed over distortion rating from 0 through 100 watts (<0.1% under ~70w). I found this amp in the bottom of a rock-pile of junk at the local flea market with a $40 price tag. I got it for $10.

I dont know all that much about this one, other than Sony is written all over it - most of the solid state transistors are manufactored by Sony. This amp is absolutely made in Japan. The Powersupply secion is using a pair of Fuji-Electric S2D1049. About 1/2 the datasheet is written in Japanese: 2SD1049 pdf, 2SD1049 description, 2SD1049 datasheets, 2SD1049 view ::: ALLDATASHEET :::. Unfortunately or unless I'm measuring incorrectly, they are both shorted across legs 1&3.

The rectifiers are manufactored by Sony, same for the ICs.

The amp has a detachable/removable power supply section which is wierd but not unlike Japanese manufactorers of this period.

Did I find something cool and unusual? All I was able to find on the internet about this amp is a few die-hards looking for one.

[Perry Babin]

I don't know if it's worth anything but if there are problems in the audio section, check each resistor individually. They use a lot of flameproof resistors which burn but show no signs of damage.

The power supply transistors are driven by individual windings from a transformer so they will appear shorted.

[ronrebel]

This is very good old school amp, I have two of them. they are 20 to 30 years old & have finally died.
I have had to repair them a few times but nothing major goes wrong with them.
The speaker protection circuit is top notch.