Replacement For Toshiba 2SK170/2SJ74

[2 picoDumbs]

I've lost count how many times this question keeps getting asked.

PLEASE USE THESE DEVICES

Linear Systems Matched LSJ74/LSK170 JFET pairs (Grade B) – diyAudio Store

J74/J74 Stereo Differential Kit – diyAudio Store

Linear Systems LSK170 Ultra Low Noise Single N-Channel JFET (8 Pieces) – diyAudio Store

Linear Systems LSJ74 Ultra Low Noise Single P-Channel JFET (8 Pieces) – diyAudio Store

[AndrewT]

Can we make this a sticky where Members are reminded regularly where to buy genuine devices?

[indra1]

+1

And request to the store for matched pairs of A and C grade as an alternative since the matched pairs of B grade are quite often in short supply.

[jcarr]

If you visit Akizuki Denshi and search for P-channel junction JFETs, you can find the 2SJ498-C which is being made by Isahaya Denshi. The package is TO-92S (a short TO-92).
A few of these in parallel can be an adequate 2SJ74 substitute.

??????/?e?d?s/Pch????^FET ?H???d?q??? ?d?q???i ?l?b?g???

hth

[Zen Mod]

Proposal to Mods - please make this Stickiest Sticky

Please.....

[6L6]

K170 / J74 Jfet availability is very spotty. Most, if not all, eBay sellers have fakes.

Linear Systems is trying to make the J74s but their yields are very low, hopefully we'll have a new batch soon and re-stock the store. In the short term, however, we are all waiting.

Every time a new supply seems to be available it's either a false alarm or the people selling get cold feet.

There are some devices that are similar, if not a direct drop-in replacement, but are very nice for audio. Nelson has been talking about using those in new projects.

[6L6]

Spencer's Toshiba Jfet are genuine -

FET Audio | Hi-End Audio Projects

[indra1]

Originally Posted by 6L6

...Linear Systems is trying to make the J74s but their yields are very low, hopefully we'll have a new batch soon and re-stock the store. ...

Understood. Same problem with matched pairs of other grades?

[AndrewT]

Originally Posted by AndrewT

Can we make this a sticky where Members are reminded regularly where to buy genuine devices?

Originally Posted by indra1

+1

And request to the store for matched pairs of A and C grade as an alternative since the matched pairs of B grade are quite often in short supply.

Originally Posted by Zen Mod

Proposal to Mods - please make this Stickiest Sticky

Please.....

But not in the PASS section.
Maybe in the Solid State? or if it's possible in Amplifiers?
And maybe a sticky back up in the Design and Build - Parts section.

[6L6]

indra1 - Linear has very low yields of the J74 is all grades. The store only has matches in B as that's the Idss value that are useful in the Pass circuits. Having matches in different grades would not really help the builders all that much.