to elaborate more about my question above to whether the test was done it was done with a new unit or not, while this top end test I did was only with a 1kHz wave, if you look at the THD reading of the analyzer, is still right about 0.016%
but even at 0.15% @200W is still very impressive.
 
that was really the golden age of Hi-Fi. They were pioneering new concepts and materials.

The new stuff today is nothing but a copy of older designs with a minor alterations.... Of course there are exceptions, but they are really few in between.

As far as the B-1, the more I look at the technology that went into creating it, the more I am fascinated by it. From an economics perspective..think about the extent Yamaha execs went to in order to create it. This was a true money no object effort, at least in terms of design. Unique topology, with no other commercial amplifier like it, purposely built transistors..not even used on other Yamahas. In terms of execution, of course, there are minor improvements that can be made today, but it is not hard to play Monday morning quarterback. I found myself guilty of doing that in this thread about the location of some components. But overall, think about it, there is no other amplifier alike.... and based on my personal experience and other's experiences, the consensus is that in terms sonic performance, it competes with TOTL from likes of Mark Levinson and Krell. Even by today's standards the B-1 is a fantastic piece of audio gear. This makes me even happier that I had the chance to give mine a new life.
 
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Hello everybody

Happy new year to everyone

Unique topology, with no other commercial amplifier like it, purposely built transistors..not even used on other Yamahas.

They did produce 2SJ27 and 2SK77 . 2SJ27 is not used in B1 but should be used in another unit . Manufacturing high quality semi conductors without using them is a non sense . I don't know which unit it is but it does exist in JAPAN for sure

2SJ27-and-2SK77.JPG
 
They did produce 2SJ27 and 2SK77 . 2SJ27 is not used in B1 but should be used in another unit . Manufacturing high quality semi conductors without using them is a non sense . I don't know which unit it is but it does exist in JAPAN for sure

Clinic - I recognize your picture from a DIY post on another forum and yes this proves that Super TO-3 P channel V-FET's were also produced but with poorer performance to their compliment which I'm sure is why Yamaha didn't produce an amp with them.

Also, manufacturing high quality semi conductors without using them was not non sense to my thinking. It was part of the process to producing the very wonderful 2SJ26 used with the 2SK76 in the B-2. :thumbsup:

K77 J27 02.jpg

Notice the lack of ranking code on the 2SJ27.
 
Nick

As you can see in our pictures 2SJ27 do not have any classification numbers like our favorite 2SK77
 
Hello everybody

Happy new year to everyone

Unique topology, with no other commercial amplifier like it, purposely built transistors..not even used on other Yamahas.

They did produce 2SJ27 and 2SK77 . 2SJ27 is not used in B1 but should be used in another unit . Manufacturing high quality semi conductors without using them is a non sense . I don't know which unit it is but it does exist in JAPAN for sure

View attachment 1079105
Hi Patrice, I would also disagree with your statement. Manufacturesrs of all industries create concept products. They use them as standards and lessons-learned for furure products. Look at this from a differnt perspective: if Yamaha would have produced a B-1 with complementariy V-fets, the B-1 would not be so exotic in terms of design.

As far as I can remember, these photos are from a DIY amplifier and not an official Yamaha.
 
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regarding 2SK77 rank: can anyone clarify if both letters are representing the rank or just the last letter?
 
regarding 2SK77 rank: can anyone clarify if both letters are representing the rank or just the last letter?
I'm thinking that since so far I've seen AK, AL, AM, BK, BM, CK, CM, DK, DM and even ZM both letters mean something with regard to ranking but I don't have a clue what the letters mean and I doubt anybody does anymore.

2SK77 AK.jpg 2SK77 CK.jpg 2SK77 DK.jpg
 
I'm thinking that since so far I've seen AK, AL, AM, BK, BM, CK, CM, DK, DM and even ZM both letters mean something with regard to ranking but I don't have a clue what the letters mean and I doubt anybody does anymore.

View attachment 1079394 View attachment 1079396 View attachment 1079404
It would be nice to know, but I guess is not that important when all 4 are a match. I guess you would really need to know when they are not..then you need to pull out that Tex T-Rex of yours to look at their curves :)
 
I sure will enjoy it for many years.

Based on the limited time I had with the B-1 so far, It is the best amp I listen to so far. I will eventually set it up with a proper source and room layout at some point in the future, but these are my initial thought when comparing it to my other amps on duty:

My MX has balls to the walls, pushes well over 300W and its sound is crystal clear at any listning levels. The B-2 is sweet as a peach and a pleaseure to listen to, nice and smooth musical sound. .....
Neither of the two can do what the B-1 can with a set of speakers. I specifically used it to play a fast, bass heavy mix straight from my phone. No pre, no tone control, nothing. That usually sounds awful on my other amps including the B-2 which is very forgiving. The B-1 sounds fantastic because of the ease of control it has over the speakers at any frequency. I first used it on my crappy and sacrificial test speakers, then hooked it up to a set of NS-1000. Who says the B-1 is shy on highs, needs to have their B-1 restored. Who says that the NS-1000Ms are bass shy, they need to hook them up to a B-1. :D:D:D

I am curious how the B-1 will fair against my BX-1s and against my TA-N7. Can't wait for the day I will have the time to do a proper listning of all of them...hopefully fed from a GT-2000 or a PX-1, via one of the C-1s :D

I would be curious to hear how the B-1 stacks against the BX-1

Awesome work rottalpha, I will be starting to restore my B-1 with UC-1 shortly and will be certainly looking at the caps replacements and upgrades you did.
Thank you for making this restoration available.

B-1 is certainly a favourite on my stand, followed closely by 2 B-3' run as mono blocks.
 
I would be curious to hear how the B-1 stacks against the BX-1

I will find out one of these days.

B-1 is certainly a favourite on my stand, followed closely by 2 B-3' run as mono blocks.
The B-2 sound so close to B-1, I wonder how I would ever hear something in-between

Awesome work rottalpha, I will be starting to restore my B-1 with UC-1 shortly and will be certainly looking at the caps replacements and upgrades you did.
As you saw, it is not impossible, but it is very difficult due to size limitations. I strongly suggest you exhaust every possible option of obtaining a kit from Clinic or a board from Vint Age, first, before you go to the full DIY route.

Thank you for making this restoration available.
I was feeling guilty to keep hijacking your thread :D
 
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