Bag O Fun 2

[Nelson Pass]

Here are 3 more scans for Bag O Fun:

www.passlabs.com/temp/thr_os89.tif

www.passlabs.com/temp/thr_fe89.tif

www.passlabs.com/temp/thr_fe90.tif

os89 was the generic output stage for the Threshold
products in 1989. You will see that it is divided up into
sections for different products. It used the MJ15022 thru
25 type devices.

fe89 was the so-called "optical bias" front end.

fe90 was the last bit of circuitry I did at Threshold, and was
an improved front end which had less thermal drift. I am
unsure that it ever went into production, but I did hear that
it was being offered as an update mod.

 

[Mark A. Gulbrandsen]

Ahhhh, so thats what was inside of my S-300 back in the 1980's. I always liked that amp alot! Am now constructing a pair od Aleph 2's though and am looking foreword to the experience.

Thanks for all your articles and construction projects over the years. The DIY audio community couldn't exist with out you!!
Mark Gulbrandsen
Salt Lake City

 

[mefinnis]

As promised

http://www.health.adelaide.edu.au/icu/files/threshold_stages_89_90.pdf (236k cf 3x700k)

For those who like this sort of thing!

Desmond will actually collate all of these on the Pass website in due course, but in the interim please use the above.

cheers, mark

 

[lohk]

Thanks Mark !

 

[Nelson Pass]

Here is today's fix:

www.passlabs.com/temp/forte40.tif

This is an extremely fine phono stage, marketed in
1990, and much better than its reputation, which is none.

 

[lohk]

Thanks Nelson Pass !
(twice actually - I somehow missed that before, sorry)

Some questions:
J2 switches to higher gain - with the input adjustments it looks MC ready: But good and noiseless enough ?

What is the job of the cap parallel to the output?

What transistor substitutions would you recommend for the NPD5566(totally unknown to me) and the 3N172 ?

Klaus

 

[mefinnis]

'Tis in the same file as above ....

http://www.health.adelaide.edu.au/i...tages_89_90.pdf (now 300k)

 

[Stefano]

can't find

Hello guys, sorry but i can't see your pdf, is it possible to send it to me? If is possible this is my lindirizzo@virgilio.it. Tank you.

 

[mefinnis]

Sorry !

I copied the link from the first post which was castrated 🙁

Try:

http://www.health.adelaide.edu.au/icu/files/threshold_stages_89_90.pdf

cheers, mark