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Yamaha CR-420 Restoration Questions

I expect the final value to be close to 600 Ohms. For convenience, you can replace the 1.2k resistors by 750 Ohms and let the legs protrude under the board. It will be easy to shunt temporarily the 750 Ohms resistor by simply pinching with your finger another resistor, until you have the lowest offset. Then you cut the legs and you solder the shunt resistor under the board. For this you need a handful of values.
 
The new caps are all installed. I went ahead and replaced all of the electrolytics with either Elna Silmic IIs or Nichicon FGs for the values which I couldn't get Elnas.

I'm going to give them a bit of time to break in, but already, there is quite an improvement. Highs are smoother and more detailed. Lows have more weight and are more defined. The mids are a bit more tubey. Sound between tracks is much more "black". Difficult sections are handled much more easily.

I have still not futzed with those resistors to tame the DC Offset. Everything is stable, and I'm not really hearing any perceptible distortion, so I may hold off on messing with that for awhile.

I have a Jico SAS stylus on the way for my m97xe, so I'm excited to hear how this changes things. It sounds pretty darn great as of now.
 
Another question I meant to throw out earlier...

The phono level is a bit lower than the other inputs (aux and tuner are fairly equal). I know a lot of this has to do with the turntable/arm/cartridge output level, but is there something else I should look into to try to get the level up to match the others?

Thanks again!
 
You could replace resistors R207 and R208 on the phono board. But at the same time it would change the operation point of the transistors and possibly reduce the overload margin of the preamp. So if you do a change, keep the change small. For example, if you replace the original 330 Ohms by 270 Ohms, you will increase the gain by approximately 1.7dB. That is the maximum change I would do without extensive evaluation of the phono circuit.
 
Just replaced those resistors, and thanks to you guys, I now have offsets of about 0.5 and 4.5 mV! And that, as they say, is close enough for government work.
Thanks so much for helping to get this gorgeous piece of gear back up and running!
 
That's correct. I just replaced R407 and R408 with 620 ohms in each spot. The offset was so close just by doing that, I decided not to bother fiddling with it any more. I'm sure they could both get to exactly 0, but to what end. I'm satisfied. Everything sounds fantastic.
I have a Dual 1228 on the way to replace my Pioneer. A Jico SAS is also on its way for the m97xe. All in, it should be a great setup!
 
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