Hi,
Thank you for reading my question.
I'm interested in upgrading/modding the amp in an old Yamaha receiver and wondering if it is feasible to do it with one of Pass designs that are available in the store.
I am a newcomer to working with electronics and don't know enough yet to be able to think my way through the project.
The heat sink is approximately 8cm by 16cm. It is 20 watts per channel into 8 ohm
I've attached 4 pictures of the inside of the case.
The model is a Yamaha CR-240.
I tried to paste a link to the hifiengine info page, but the forum would not allow me to post a website link.
Any advice would be appreciated.
Thanks in advance.
Thank you for reading my question.
I'm interested in upgrading/modding the amp in an old Yamaha receiver and wondering if it is feasible to do it with one of Pass designs that are available in the store.
I am a newcomer to working with electronics and don't know enough yet to be able to think my way through the project.
The heat sink is approximately 8cm by 16cm. It is 20 watts per channel into 8 ohm
I've attached 4 pictures of the inside of the case.
The model is a Yamaha CR-240.
I tried to paste a link to the hifiengine info page, but the forum would not allow me to post a website link.
Any advice would be appreciated.
Thanks in advance.
Attachments
Alternately, would it be better or more "doable" to mod it so that it is a "preamp" instead of an amp? Then I could use any external amp...
Yes, the heat sink is too small for much else, just disconnect the R701 and R702.
To have preamp outputs, tap off the wipers of the volume control and ground,
to a pair of unneeded RCA jacks on the back. The tuner will still work too.
To have preamp outputs, tap off the wipers of the volume control and ground,
to a pair of unneeded RCA jacks on the back. The tuner will still work too.
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I don't like modifying or upgrading hi-fi equipment, but, in your case, maybe should be good to replace the speaker relay. If in close position, is not zero ohms, replace. I like Schrack RT445024 relays.
Maybe you have to place a resistance in paralell or modify R419 for to adapt 24V. This relay uses minus power than original. Another thing should be check electrolitic capacitors, above all these purple Matsushita capacitors, check if there is green rust in their pins.
Maybe you have to place a resistance in paralell or modify R419 for to adapt 24V. This relay uses minus power than original. Another thing should be check electrolitic capacitors, above all these purple Matsushita capacitors, check if there is green rust in their pins.
There's really not much you can do with that amp, honestly.
It is what it is... period.
Replacing some tired worn-out capacitors maybe.
It is what it is... period.
Replacing some tired worn-out capacitors maybe.
Thank you for the insight.
As I mentioned in the original post, I'm new to working on electronics, so please forgive me for asking for clarification.
What is the "R701 and R702" that you mentioned?
For the preamp outputs, what do you mean by "wipers" of the volume control and ground? Does that mean the leads/connectors that are soldered to the volume knob?
Also, did you mean that I should first disconnect the r701 and r702, and then to connect the volume control, or were those two separate things?
Thanks so much for your advice.
Okay, thank you for all of that advice. I didn't think about the speaker relay and the need to replace it. That's interesting.
Thanks for mentioning the capacitors and the green rust. Does green rust mean they have gone bad?
Thank you. I've thought about this too. It is what it is. But then again, how do I convince the DIY tinkerer part of my brain?
Study the schematic, parts list, and service manual carefully. You have to be able to locate each part
on the printed circuit board in order to work on the unit.
https://www.hifiengine.com/manual_library/yamaha/cr-220.shtml
on the printed circuit board in order to work on the unit.
https://www.hifiengine.com/manual_library/yamaha/cr-220.shtml
Hello.
Is a very interesting question, because is very probably that the capacitor is ok, with its characteristics inside limits, but, the problem is the rust, that can reach the printed circuit or other components.
And yes, old relays are problematic, rust or dirt is located in their contacts, and sometimes it sounds like distortion, and the problem is the relay. Solution: New relay with contacts at vacuum, with no air.