Phaser JFET selection

[genXslacker]

I'm going to build another Phase 90 using 2N5952's.

All else equal, i.e., matching V_GS, does it make even a theoretical difference if I use higher or lower V_GS JFETs?

I've sorted 100 of them, and I have several matching sets to choose from.

 

[jimilee]

Yessir. Here’s an article all about it.

geofex.com/article_folders/fetmatch/fetmatch.htm

 

[genXslacker]

Yessir. Here’s an article all about it.

geofex.com/article_folders/fetmatch/fetmatch.htm

I've seen that article, and I'm not sure it addresses my question.

Let me ask it this way. If I have a set of four matched 2N5952s with a V_GS of 2.10 and another set matched at a V_GS of 2.50, is there any reason at all, even theoretical, to favor one set over the other?

 

[Audandash]

The article is a little vague on this but there is one sentence towards the end that applies here.

“A phaser needs JFETs that are all in the resistive range - not fully on or fully off- at the same time.”

So it may be minimal and i don't have the data sheet in front of me for the 5952 but if there is a sweet spot thats in the middle that its closer to, whether its vgs2.1 or vgs2.5 in your example, that should be the ideal set. Will they both work, yes. Will you be able to tell the difference? Maybe, but i doubt it. When in doubt socket and see and listen to your ears.