B2

[clinic-audio]

Welcome on AK !

I will strongly recommend you to not buy any of these TR ! they don't have them and I can proove it by posting the same picture (without chinese letters)

this picture is dated april 2013 (you see it is not recent )



this picture is not a proove that they have them ! And you can see that they are not new (screws traces)

 

[endeeinn]

Yes.

Not many people will have vfets just sitting around to sell, one of the few people I know who has legitimate ones is @clinic-audio on this forum who you can contact via PM. They won't be particularly cheap but at least you know they're genuine.

I second contacting Patrice at Clinique Audio (cliniqueaudio@orange.fr). I have dealt with him and I have found him to be extremely competent, honest and with very pleasant to work with.

 

[David Litman]

Hi Zaibatsu, well . . . thank you for your time to reply though, not really what I wanted to hear. But, I'm a determined kind of chap and won't give up. I'll check out @clinic-audio and see what I'm into there. I guess your quite right in that I should find someone who know's about this baby, I mean B-2 before I do anything. I am a stranger in a strange land, that is to say I'm an Englishman living near Glasgow in Scotland. Would you know of someone nearby? Or. in the UK or Europe even?

 

[David Litman]

Ok, took your advise and have sent drive boards, v-fets and heat sinks to B-2 speacialist in France. Will let you know progress.

 

[David Litman]

Hi all you gentlemen out there. So, I paid the bill to Patrice Hassen at Clinique Audio in France, September last year for repairing my beloved B-2 and supplying four new Radial "Gold Tune" caps. After 14 emails, I still have had nothing back. Only promises. He is not answering any more. Is this normal? What can I do, please?

 

[zaibatsu]

@clinic-audio
Time to respond!

 

[clinic-audio]

Hello everybody

1) AK is not the place to discuss from troubles with members
2) my mail box is working perfectly well and I answer to every one within the best possible delay . I do not answer to repetitive mails . One answer is enough no time to loose
3) I have customers who are waiting since a long time for repair and deserve respect, and to do them first
4) I am really disapointed to see that one member send message like if I would be a tief or a liar

do you know somebody able to supply you this :

PCB work in progress


Cleaned PCB after repair


Washed heatsink


Washed heatsink detail on brand new (impossible to find ) V-FET


Watch for your postman before to yell "clinic-audio don't answer anymore" ! what can I do ?

2 hours labor (only) charged for repair two driver boards and two heatsinks + complete check the 8 V-FET with curve tracer .....

I don't really think to do it again !

 

[stoutblock]

Looks like nice work!

 

[rottalpha]

Hello everybody

1) AK is not the place to discuss from troubles with members
2) my mail box is working perfectly well and I answer to every one within the best possible delay . I do not answer to repetitive mails . One answer is enough no time to loose
3) I have customers who are waiting since a long time for repair and deserve respect, and to do them first
4) I am really disapointed to see that one member send message like if I would be a tief or a liar

do you know somebody able to supply you this :

PCB work in progress
View attachment 1465693

Cleaned PCB after repair
View attachment 1465694

Washed heatsink
View attachment 1465695

Washed heatsink detail on brand new (impossible to find ) V-FET
View attachment 1465696

Watch for your postman before to yell "clinic-audio don't answer anymore" ! what can I do ?

2 hours labor (only) charged for repair two driver boards and two heatsinks + complete check the 8 V-FET with curve tracer .....

I don't really think to do it again !

are K98/J38 suitable replacements for K76/J26?

 

[Vint Age]

are K98/J38 suitable replacements for K76/J26?

Not for mine!

 

[rottalpha]

Not for mine!

that's what I thought

 

[clinic-audio]

I have decided to use usual B2 V-FET after the damaged 4 new 2SK98 and 2SK38 .
Everything is working well now with 2SK76 and 2SJ26

 

[Vint Age]

Everything is working well now with 2SK76 and 2SJ26

 

[rottalpha]

I have decided to use usual B2 V-FET after the damaged 4 new 2SK98 and 2SK38 .
Everything is working well now with 2SK76 and 2SJ26

Yep, organ's organs do not belong in a B-2

 

[David Litman]

Gentleman, I got my B-2 drive boards, fully assembled, back 4 April. Everything looks really beautiful. I have installed the PS smoothing caps, also supplied and am now scratching my head how to do "overall adjustments" and "adjusting power supply voltage". In the service manual, firstly, to do the "overall adjustment" you need the drive boards connected (p11 fig1). But, I have been advised not to connect them until the power supply voltage is set to +85V and -85V. Is there anywhere here (or anywhere else) a clear step by step instruction on how to do this, written for dummies, having never done anything like this before, please?

 

[rottalpha]

Gentleman, I got my B-2 drive boards, fully assembled, back 4 April. Everything looks really beautiful. I have installed the PS smoothing caps, also supplied and am now scratching my head how to do "overall adjustments" and "adjusting power supply voltage". In the service manual, firstly, to do the "overall adjustment" you need the drive boards connected (p11 fig1). But, I have been advised not to connect them until the power supply voltage is set to +85V and -85V. Is there anywhere here (or anywhere else) a clear step by step instruction on how to do this, written for dummies, having never done anything like this before, please?

the B-2 service manual has very well written adjustment procedures.
If your PSU board still has the original trimmers, the adjustment is done from the back of the board (facing up) through the two hoes at the lower right section (as you are facing the amp). use a small plastic flat screwdriver to prevent any operator error slip.
you will need a volt-meter with small hooks. Do not trust the staidness of your hands with pointy meter probes...not worth the risk
if you still have questions, let us know

 

[David Litman]

Hello Rottalpha, thank you very much for your input. Yes, I do have questions. Please see photos attached (sorry for poor quality). First, one of the over-hauled and calibrated, driver units. Then a picture of the driver board. So, without the driver board unit fitted, one attaches the probes to one of the green wires and then the orange wires to adjust? But, which is 'E', or earth? Would that be 'GR', (ground)?
Can I presume that 'Step 1' in the manual (100V) is done after 'Step 2' (+85V / -85V) and then fitting the driver boards.
Soory to ask what may be straight forward to you but, as my picture implies, I'm "not to swift to behold".

 

[Vint Age]

Soory to ask what may be straight forward to you but, as my picture implies, I'm "not to swift to behold".

Not wanting to be a nay sayer here but the B-2 is not the best amp to be cutting your teeth on. One mistake and ...

 

[MiamiBoy]

....now scratching my head how to do "overall adjustments" and "adjusting power supply voltage". In the service manual, firstly, to do the "overall adjustment" you need the drive boards connected (p11 fig1). But, I have been advised not to connect them until the power supply voltage is set to +85V and -85V. Is there anywhere here (or anywhere else) a clear step by step instruction on how to do this, written for dummies, having never done anything like this before, please?

David, I won't advise you on how to test a B2 disassembled, if that is what you are trying to do. But I can share with you a copy of B2 adjustment instructions I prepared for myself that is detailed and simple to follow. I wrote it for myself so by definition it is written for dummies. I always use it rather than the steps in the service manual when adjusting my B2's. If you message me your email address I will send you a copy.

 

[David Litman]

Hi MiamiBoy. Thank you for your input. Yes, I would very much like to see your instructions. I see in my post I described the pic of the power board as a driver board. My bad!

Is there a way to Private Message my email address to you?

Thing is, "B-2 Expert" who overhauled the drivers says I should calibrate output from power board before I hook up the driver boards or there is a danger ruining the driver boards. Hence, my confusion with the manual as it says to do "overall calibration" first which, would need the driver board in place to do.

Am I overcomplicating things? Or, have I completely missed the point?

Thank you in anticipation.