B2

Highly recommend trying a tube preamp with the B-2.

I highly recommend no preamp at all. If you truly want to hear what your B-2 can do, assuming you have a good digital source, connect it directly to the B-2. If it has a variable output, even better. Pick your best recording and listen to the music come alive. :tresbon: :yes:
 
Hello Nick

I am working ( finishing) on C1 (2) B1 (3) and just receive this B2

What do think about these transistors . The size is not the same ( like in another post )

I take pictures recto-verso of each Power Transistor but somebody wrote on them and this is made in JAPAN .

I don't know why but I feel these transistors are recent see code numbers ...
Did you ever met such case before ?
 

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Other pictures ..

:scratch2:

Just want to add that the 2 2SK76A are shorted :thumbsdn:
 

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Hello

I have probably refixed 20 B2 but I never saw any similar hand writting on the back of any VFET I have deleted for replacement ...Before this one !
 
Hello

I have probably refixed 20 B2 but I never saw any similar hand writting

All 3 of mine have similar hand writing. The K76(A)/J26(A) are unlike the Yamaha 2SK77's and Sony's V-FET's that have their ranking code marked on the top near the part number.

As you know, you will need 2 2SK76A that closely match the 2 functional 2SJ26A to fix your B-2 properly. If it were mine I would want to replace all 4 devices in that channel since the J26A's will have likely suffered from major DS current stress and the possibility of failure in the future is very high. :yes: :tears:
 
As you know, you will need 2 2SK76A that closely match the 2 functional 2SJ26A to fix your B-2 properly.

You are right , I know that but all my new transistors are blank no hand writting nowhere ..

:yes:
 
As you know, you will need 2 2SK76A that closely match the 2 functional 2SJ26A to fix your B-2 properly.

You are right , I know that but all my new transistors are blank no hand writting nowhere ..

:yes:

This is where a curve tracer becomes very useful ... :thmbsp:
 
Yamaha B-2 transistors

Dear B2 aficionados,

I’ve just finished restoring a B-2 during which I replaced a bunch of transistors that are prone to a high failure rate:

2SC458 by KSC1845
2SC1061S by TIP31C
2SA671S by TIP32C
2SA740A by MJE15033
2SC1448A by MJE15032
2SA872BV by 2SA1145Y
2SC1775A by 2SC2240
2SC1775BV by 2SC2705Y
2SC789 by 512-KSD526Y

Do you recommend other changes?
For example I read in one of the forums that the 2SA810 and 2SC1452 can also be problematic.

Thanks.

***Long live the B-2***
 
Hello !

I will replace original obsolete TR by :

2SC458 by 2SC1815
2SC1061S by 2SD313 or 2SD526
2SA671S by 2SB596
2SA740A by 2SA940
2SC1448A by 2SC2073
2SA872BV by 2SA1016 or 2SA970
2SC1775A by 2SC2088
2SC1775BV by 2SC1845 or 2SC2240
2SC789 by 2SD313 or 2SD526

But if you are satisfied with yours keep them .

Regarding 2SA810 can be replaced by 2SA778K
And 2SC1452 can be replaced by 2SC2229

To be honest , yes , I have replaced those TR (2SA810 and 2SC1452) in B1 and B2 because they often fail .....:yes:
 
Having been on sony esprit and Vfet gear for some years, i now invested in some yamaha vfet gear.
- bought a B-2 last week, in very good condition. Received it today, boy what can i say!!! Unbelievable
- my b-1 is at Patrice for a big restauration job
- I am working myself on a sony ta-n7b
- the other already restored ta-n7b is in my second system
- like the ta-n7b in combination with a tae88b, the b-2 is combined with a c2x
- I am selling all my CD players, also sold my sony R1 set, i completely switched to streaming with La Rosita hardware from France. unbelievable in combination with the c2x and b-2
 
- I am selling all my CD players, also sold my sony R1 set, i completely switched to streaming with La Rosita hardware from France. unbelievable in combination with the c2x and b-2

If the La Rosita hardware has a variable output, try it directly into the B-2 and see what you think. :thmbsp:
 
If the La Rosita hardware has a variable output, try it directly into the B-2 and see what you think. :thmbsp:

One can order teh La-Rosita with a built in pre-amp, but i did not. I read that deleting the pre-amp on a B-2 is the next step in SQ.
The La Rosita uses a dedicated itunes plug-in that is the key to their succes. I switched of volume control via the pc, because to my opinion that is the worst volume control one can have.
Leaves me only one option to use the attenuators on the B-2 to set the volume. I also have somewhere a high quality 46-stepped attenuator, i think 50K. I could also use that.

What i forgot to mention is that my last desired yamaha is the NS-1000. I have acquired last year a NOS set of units, filters and attenuators, all in their original yamaha boxes and sealed.
I am designing a new cabinet for them matching the original cabinet as much as possible.

regards

Harold
 
A NA06750 that shows very little, if any, bowing with age.
by the regulators glue still holding
 
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Yes Vintage it sure does, I never fail to be impressed by a B2 that is in pristine condition and there are lots of really good ones out there that have stood the rigors of time.

The B2 has and you’d agree has such a simplicity and beauty of design that couldn’t be bettered, well except for the NA06750 positioning as a heat and dust collector.
 
Rust is Disappointing on any classic, and RCA’s tarnished, inappropriate storage perhaps or is climate a big factor in the States ?
 
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Hi Guys,

It has been great reading through this thread, and the reason for it is because I have just bought a B2 with one channel faulty. I guess the Tech thought that the vfets are dead but I have tested them using I think, Echowars' advice and found them ok.

There was mention in those archived posts of a data sheet for the 2sk76a and the 2sk26a, could someone possibly post them for me, I need to confirm the pinouts.

I hope to rebuild my B2 soon and find out that it is only the switches that have failed.

Thanks in advance

Chris
 
Hello Chris

Welcome on AK !

Here is the answer to your question
 

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