Yamaha B-3 V-fet restoration

:rflmao:

Bass sound tighter and slightly deeper to my years with the new cans! The reason I looked in the first place was because turning up the volume made the highs slightly grainy... Was no visible signs of leakage but when out and measured one cap was way off specs
Original cans physical size verified to be 63mm x 105 mm
 
Wow...The magical V-FET trio, B-1, B-2 and B-3. Lucky man! Seems like they put more metal in the B-3, the last of them... Sound-wise, only you can express an opinion. Comments regarding the sound of the three?
 
Wow...The magical V-FET trio, B-1, B-2 and B-3. Lucky man! Seems like they put more metal in the B-3, the last of them... Sound-wise, only you can express an opinion. Comments regarding the sound of the three?
More metal?? not sure what you mean..both B2 and B1 are substantially larger and heavier than a B3...as a matter of fact, the B-1 is more than twice as heavy, or heavier than two B3s, however you want to put it.

Can't comment about the sound yet, but I will eventually do a side comparison at some point. All I can say for now is that if they sound as good or close to the rest of the family, they are keepers.
 
vintagejapan, looks great! I am sure everyone understands your assertion regarding the sound with the brand new filtering capacitors. I hope the B-3 performance is way much better than before the refurbishment.
If you have more pictures with the internal boards of the B-3 to see what electrolytics you installed, I will be delighted to follow your updates.

As a curiosity, how do you open the metallic top lid of the B-3? There are no screws visible. I have opened many times the bottom lid (easy procedure), but never measured the main caps dimensions.

What preamp and speakers you pair with the B-3?

I know, too many questions...Thanks!
As Pete mentioned sides screws off and the top cover pops out.

At the moment running the B-3 with a Luxman CL-36 modified tube pre. Speakers sometimes Pioneer S-955III and other times Yamaha NS-2000. Both speakers are a great match for the B-3. I still have 3 weeks to go before some time off. Will try to finish this project then and post all the pics as I go.
 
Indeed. Correct Japanese parts for vintage Japanese gear.
I just don't get it why people would stuff a given heritage piece full with foreign parts.
It's not about functional only (for me) , but also about preserving an authentic built.
true that!

one observation about the suggestion I made is that it still needs to be physically verrified as in: pull out an original, take physical measurements of it, then compare against the datasheet of the Omron....or the Panasonics in the first link.

I allways had good experience with Omron for the same reasons you named. ...If fits like a glove with the same footprint an similar exterior dimensions as the older Japanese relay is replacing.
 
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@rottalpha
Thankyou, yes I have one pulled out on my desk here.
I can take some measurements if needed.

The original part is a Matsushita (i.e. Panasonic) HC4 which is why I asked about those.
HC4a-P-DC24V is the original PN.
 
@rottalpha
Thankyou, yes I have one pulled out on my desk here.
I can take some measurements if needed.

The original part is a Matsushita (i.e. Panasonic) HC4 which is why I asked about those.
HC4a-P-DC24V is the original PN.
yes, a panasonic or anything Matsushita replacement is allways good if available.

I think the comments above were about the other brand from rs-online

Please let me know if the actual measurements of your pull match the data sheet from any of the Pannies you linked, or the Omron I suggested
 
Please let me know if the actual measurements of your pull
Just measured mine:

27.8 x 21.5 x 33.5mm (LxWxH)

Terminal outermost width: 13.5mm (measured from center to center of outermost pins)
Terminal outermost length: 17mm
Terminal lengthways gap spacing: 4mm (between "front" two rows of 4 pins), 6.5mm (between "middle" two rows of 4), 6.5mm (between row of 4 and 2).

Hopefully that makes sense.

Closest match (esp. for height) looks to be the Panasonic relay. Omron probably fits but spec says it's a bit taller.
Pretty sure the one you linked is correct, HP means solder pins = matches stock.
Same relay at mouser PN: 769-HC4-HP-DC24V.
 
So back here. On the power supply board. Replaced all the electro's. Also replaced the 4mylar 0.01 caps. The should be of the same size with the originals or smaller. When board is installed there is really no room for taller replacements.
IMG_7201.JPG IMG_4772.JPG
 
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