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vintagejapan

Yamaha B-1 Vfet monster, restoration

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7 minutes ago, vintagejapan said:


Thanks Pete!

This was a special occasion!

Nice B-1 that will be singing for another 40+ years or hopefully more.

The ZM K77s are somewhat rare. 

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20 minutes ago, Grizzly said:

Thanks! I had a B2 previously that went pffft. Still needs to be sent away for resurrection. I must get around to doing thatemoji16.png
 

22 minutes ago, Grizzly said:

If memory serves you've done a few of these yourself?

Yes.

 

sorry to hear about the B-2. The B-2 has the sweetest sound of the V-fet amps. I hope you get it back to prime.

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Nice B-1 that will be singing for another 40+ years or hopefully more.
The ZM K77s are somewhat rare. 

Indeed. This was the only 240v B-1 I have seen.

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12 minutes ago, vintagejapan said:


Indeed. This was the only 240v B-1 I have seen.

they are rare because very few were exported to AU and Europe....actuly I learned that they were only exported to England and not to the rest of Europe. The British were also the only ones that got the silver versions of both, UC-1 and C-1.

 

About the power consumption (you mentioned this on a separate thread)..700w vs 440w that you see on the Japan models and older US models....

I know of at least 4 flavors of B-1 rear panels. Japan and early US models will say 440w and all 240v models and newer US models (thinking serial number 1800+) will say 700w.

 

The power consumpion stated on the box varies from market to market or point in time, to cater to the local codes. It really does not matter as all B-1s will consume more than 700w if pushed, agnostic of what the box sais. As a matter of fact, at over 200w, the B-1 sucks 1kw

Edited by Rottalpha

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20 hours ago, Rottalpha said:

they are rare because very few were exported to AU and Europe....actuly I learned that they were only exported to England and not to the rest of Europe. The British were also the only ones that got the silver versions of both, UC-1 and C-1.

 

About the power consumption (you mentioned this on a separate thread)..700w vs 440w that you see on the Japan models and older US models....

I know of at least 4 flavors of B-1 rear panels. Japan and early US models will say 440w and all 240v models and newer US models (thinking serial number 1800+) will say 700w.

 

The power consumpion stated on the box varies from market to market or point in time, to cater to the local codes. It really does not matter as all B-1s will consume more than 700w if pushed, agnostic of what the box sais. As a matter of fact, at over 200w, the B-1 sucks 1kw

Great info!

 

I did notice the power bill went up slightly when the B-1 was playing.. 1kw :w00t:

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So now that you are done with the project, maybe you find some time to get those readings off of the mx-1k trafo secondaries for me ??

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