Bias adjustment for "click off" on CR-2020

pretty boy

Hey I thought I'd post the completed unit. It looks like every other CR-2020 which is good ;-) The case was is such good shape I could not bring myself to alter it in any way save some extra holes in the bottom for ventilation. Those holes are right under the holes in the chassis, right under the main caps. All in an effort to keep that whole hot area including those tr712, 715 transistors cool. I don't know if it will help but it can't hurt :)

I added a second set of heat sinks to the stock ones after I tried one more time to get the insulators to do there job using the jumpers to the the front of the chassis I had in place before, you know the ones that caused all the heart ache! I don't know how that fellow did it in the picture I saw in a thread here earlier about a CR-2020 rebuild but it must have been a better insulator kit that what I was able to come up with. I can only figure that the hold down screw was too fat and made contact with the transistor despite the grommet. Stupid grommet! So screw it! I went for a more standard fix.

I put some LEDs in. I used the 20 volt LB tap and daisy-chained them - easy! They are "white" except I sanded the surface of them and used a green sharpie on them to make them the right sade of green. A blue-green to match the pointer. Just a little custom touch, very close to stock.

It has been a great ride. Thank you each and all for your help. I would have given up if not for you.

Cheers!
 

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I'm giving it a couple of days to break in all the new caps. I sat for a few tracks and beer earlier...there is great promise there ;-)
 
good beer thinking

I usually wait 48 hours to take stock of a new unit but a second listen and a second beer last night as well as a third listen with a cup of coffee this morning has me ready to say without reservation: it is one very nice unit!

I'm pretty spoiled; I have always spoiled myself when it comes to the basic pleasures of drinking/eating and music. My main stereo is a SET. Once bitten by that bug there was no stopping until I had run out of money and skill to make it even one tiny bit better. When it was done I still had the need for the "thrill of the chase" so I started working on old receivers. In a similar vien I used to make my own beer from scratch, now I just go to the tap room.

I'm just smart enough to know my limitations ;-) There are brew masters I'll never touch and amp designers I'd buy beer for all night long to hear them speak. What fun just to try to understand something new and personally delightful (given a finite number of beers :)

Anyway, it is far easier to appreciate quality than to make it happen. The folks at Yamaha were on their game alright way back in '78. I never got to hear one at the time. I knew they were out of my league, being just a freshman at college. 262 credits later I have not lost my thirst for all things bold and beautiful. I'll have my Yammie now until my own capacitors exhaust themselves.

Cheers all! :beer::yippy:
 
Yea, I agree. They were on their game. I bought my CR2020 years ago and just threw it into service in the bedroom hooked up to a pair of Sonus Faber Concertos. It was on 24/7 for a few years as the flat screen was hooked up to it also. It finally failed and I just chunked it under the bed and replaced it with my McIntosh MAC4300. A few months ago, cleaning up for the painter, I found the old broken CR2020. I was heading to the trash with it when I just started to realize how nice the wood case was, the heft of the the transformer, etc. I stopped and instead placed it on my work bench for a winter project, or to strip down for parts. I found the service bulletins and opened it up. Sure enough the PS was toast. With help from this forum and Brad the King, I fixed the power supply and got it up and running. It sounded like it did when I first got it. Not real good. It had that solid state etch to the sound. I am a tube guy myself. But I went ahead and recapped the entire receiver. My ole my was I surprised when I gave it another listen after a few days of break in. Wow, very nice. A very refined sound with plenty of punch but easy on the ears. I had never heard this beast. It was toast when I first got it, I just did not know it! It is a keeper. Nice Yamaha! Nice! :yes:
 
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all amps sound alike

I have heard this so many times, "all amps sound alike". "You can use coat hanger wire for your speaker wires and no one can tell." Well I can tell when you change caps in a amp (and so can you obviously) it is not that subtle! Even in a new amp I can hear changes when Better caps are used artfully throughout the amp. I can only imaging what it is like to live inside the head of someone who thinks all amps sound alike :no: It would strain their manners to hear us talk of "new sound" from the same circuit simply by changing the caps. They might start a fight to hear us debate about what kind of cap change might yield the best results. I can hear my own dad say in my mind, "You can't possibly believe that crap!"

The other hard truth for some to swallow is that newer does not necessarily mean better. They made some good old amps they make some good new amps. Some of the paper and oil cap constructions are still the best for some applications some of the new teflon stuff just really knocks me out. I am happily amazed by all the variety out there. I am happy to be among those who note the differences and enjoy playing with the stuff that others have brushed aside. Many thanks to all those that make this play possible!

Cheers!
 
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