AC Converting a Threshold NS-10

[RobertS61]

Yep.
Hope it goes well. Keep you posted.

This is showing the Japanese admiration for old Threshold stuff:
https://www.diyaudio.com/forums/attachment.php?attachmentid=989140&stc=1&d=1633805919
https://www.diyaudio.com/forums/attachment.php?attachmentid=989141&stc=1&d=1633805919

Mark Levinson, Nelson Pass were a kind of heroes for the audio community.
Their Shinto believe (I Believe ;-)) says that every object has a soul. So they really like the souls of American made audio gear. They cherish it.
https://www.diyaudio.com/forums/attachment.php?attachmentid=989142&stc=1&d=1633806226
https://www.diyaudio.com/forums/attachment.php?attachmentid=989143&stc=1&d=1633806226
https://www.diyaudio.com/forums/attachment.php?attachmentid=989144&stc=1&d=1633806226

 

[RobertS61]

Tantalum to be replaced?

As said I have two S/500 optical bias versions.
Which part of the frontendboard should I replace. A tantalum I believe with what replacing part?

https://www.diyaudio.com/forums/attachment.php?attachmentid=989183&stc=1&d=1633810738

 

[Zen Mod]

value of Tantalum?

(we are calling them Popcorns, nowadays)

 

[RobertS61]

This one:

https://www.diyaudio.com/forums/attachment.php?attachmentid=989184&stc=1&d=1633811016

 

[Zen Mod]

I saw it on first pic, just asking for value

🙂

 

[RobertS61]

value of Tantalum?

(we are calling them Popcorns, nowadays)

I have no idea.
Will look further.

But is that the offender? That yellow popcorn cap?

 

[RobertS61]

0.15 uF 35V tantalum?

 

[Zen Mod]

yeah

if value permits (size) replace it with solid cap

in size is problematic, put decent electrolytic - these days they're better than Tantals of Yore ....... if nothing else, no Popcorning 🙂

see, He's making me green even with his oldest pcbs .......... two resistors in red

 

[Zen Mod]

0.15 uF 35V tantalum?

what is exactly written on?

 

[RobertS61]

Found it:

 

[RobertS61]

https://www.diyaudio.com/forums/attachment.php?attachmentid=989186&stc=1&d=1633811648

 

[RobertS61]

what is exactly written on?

I'm sorry, these where boards from my Threshold SA/1 amps optical bias. So I've now idea what is written on them.
But is it the yellow droplike cap in the vicinity of the green ERO filmcap?
i will look tomorrow for the values. I have a couple of Copper Teflon filmcaps lying around V-Cap CuTF but they are probably too big.

 

[Zen Mod]

you know, tonight I'm lazy to search for schmtc

🙂

 

[Zen Mod]

......

This is showing the Japanese admiration for old Threshold stuff:........

He got them Softies eons ago, and it didn't change in all these years

in recent time ....... Story** goes that our friends from East shores are solely responsible that I was blessed to recognize Best Ever Papamp ......... M2

**Pa didn't had firm intention to make it in volume, but someone willing got prototype....

eons ago - see pic, click

 

[RobertS61]

Brilliant stuff.
Very nice pictures indeed.

The guy won't bother to send I have to make all the arrangements.

Thanks to the EU I would wind up paying twice his asking price...
Buy a SL-10 in Europe...

 

[RobertS61]

https://www.diyaudio.com/forums/attachment.php?attachmentid=989207&stc=1&d=1633820505
https://www.diyaudio.com/forums/attachment.php?attachmentid=989208&stc=1&d=1633820505
https://www.diyaudio.com/forums/attachment.php?attachmentid=989209&stc=1&d=1633820505
https://www.diyaudio.com/forums/attachment.php?attachmentid=989210&stc=1&d=1633820505
https://www.diyaudio.com/forums/attachment.php?attachmentid=989211&stc=1&d=1633820505

 

[RobertS61]

https://www.diyaudio.com/forums/attachment.php?attachmentid=989213&stc=1&d=1633820794
https://www.diyaudio.com/forums/attachment.php?attachmentid=989214&stc=1&d=1633820794
https://www.diyaudio.com/forums/attachment.php?attachmentid=989215&stc=1&d=1633820794
https://www.diyaudio.com/forums/attachment.php?attachmentid=989216&stc=1&d=1633820794
https://www.diyaudio.com/forums/attachment.php?attachmentid=989217&stc=1&d=1633820794
https://www.diyaudio.com/forums/attachment.php?attachmentid=989219&stc=1&d=1633820794
https://www.diyaudio.com/forums/attachment.php?attachmentid=989220&stc=1&d=1633820794

 

[RobertS61]

https://www.diyaudio.com/forums/attachment.php?attachmentid=989221&stc=1&d=1633821070
https://www.diyaudio.com/forums/attachment.php?attachmentid=989222&stc=1&d=1633821070
https://www.diyaudio.com/forums/attachment.php?attachmentid=989223&stc=1&d=1633821070
https://www.diyaudio.com/forums/attachment.php?attachmentid=989224&stc=1&d=1633821070
https://www.diyaudio.com/forums/attachment.php?attachmentid=989225&stc=1&d=1633821070

 

[RobertS61]

https://www.diyaudio.com/forums/attachment.php?attachmentid=989226&stc=1&d=1633821505
https://www.diyaudio.com/forums/attachment.php?attachmentid=989227&stc=1&d=1633821505

https://www.diyaudio.com/forums/attachment.php?attachmentid=989228&stc=1&d=1633821505
Probably at home at Rene Besne, Pass loved the small Thresholds with Horn loudspeakers I believe always a modest man.

https://www.diyaudio.com/forums/attachment.php?attachmentid=989229&stc=1&d=1633821505

 

[PRR]

In the 70's, they (Signal Transformer) were at 1 Junius Street in NYC - Brooklyn, maybe? They were the go-to XFMR supplier for budding amp builders in my dorm at MIT. The transformers were immediately recognizable due to the black impregnating varnish used.....

I can spot one across the room. Not only excellent and low-price power transformers. A forum transformer wizard presented a set of audio frequency response curves for public guessing. I held-back because I knew from the bobbin, and my own testing, what it was. The small Signal "2-4-1" power transformers had quite wide frequency response at medium audio impedances. Well past 50-15k.

Anyway: I can't see the line terminals on that PCB. But the transformer fully supports dual-primary 120/240 operation, you just have to find and sort out four connections.