• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

Group Buy: Linear Systems LSK389 / LSK170 JFETs (i.e. Toshiba 2sk389/2sk170 subs)

do you want a 389 that is tightly matched within the pair?
or do you want standard 389 and a pair of these selected for similar Idss?
the standard 389 is not a matched pair, look at the datasheet, it specifies Idss within 0.9:1 (Idss1/Idss2 has a min of 0.9)

Hi Andrew,

Sorry for the delay, I had to take the dog for an very urgent walk.............

I dont think I worded my requirement well enough..

I know they have a 0.9:1 lower limit and thats all it is, the bulk of the population will match better than that. So..

Im looking for a tight match of the 'fet pair on single 389' and I need two 389s to be matched well also..

If its too difficult or too expensive I guess I could just get 4 170s very tightly matched and then thermally bond them and wrap em up in some polystyrene to keep out the drafts.

Thanks Rob