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Linear Systems Matched JFETs

Linear Systems Matched JFETs

  • 2900


We have a brand new supply of Linear Systems matched JFETs.

Some lines might be available for back order. Before placing a back order, please make yourself familiar with how backorders work and note that we do not ship partial orders.

Product Details . 
  • Guaranteed authentic Linear Systems JFETs
  • Matched to ±0.1mA (tested at 10V / 22'C and sorted into 0.1mA bins). For more information see our JFET matching information page.
  • NP (LSK170/LSJ74) are ideal for a stereo BA-3, F4, F5, F5T, F6 and more
  • PP (LSJ74/LSJ74) are ideal for Aleph J or BA-1 gain stages
  • Please direct all technical questions to the Linear Systems JFET support thread


JFET Specifications

    • Product data: LSK170 LSJ74
    • Grades
      • A (equivalent of Toshiba Gr), Idss ranging from 2.6-6.5
      • B (equivalent of Toshiba Bl), Idss ranging from 6.0-12.0
      • C (equivalent of Toshiba V), Idss ranging from 10-20

Quantity Limits

  • Limit of 4 units per customer per month due to supply constraints. We want to ensure they all end up in the hands of builders who are going to use them for making projects, not hoarded or resold.
  • If you need more than 4 for a particular build, please email with details of your build. Our goal is to see the most amps actually built and shared with the community as possible.
  • We provide these matched JFETs as a service to the do-it-yourself audio hobbyist community and it's important that we can always keep these parts in stock for small orders from hobbyists. Please keep this in mind when ordering large quantities. If you would like to order a large quantity, please check with us first via email to

What's included

Part LSJ74
Used In
LSJ74 ±0.1mA Matched Pair (Grade B) 2 AJ BA1-GS
LSJ74 ±0.1mA Matched Quad (Grade B) 4 AJ BA1-GS ACP+
LSK170 ±0.1mA Matched Pair (Grade B) 2
LSK170 ±0.1mA Matched Quad (Grade B) 4 Mezmerize 
LSJ74/LSK170 ±0.1mA Matched Quad (Grade B) 2 2 F4 F5 F5T V1/2/3 F6 BA3-GS 
LSJ74/LSK170 ±0.1mA Matched Octet (Grade B) 4 4
F5T V3 Balanced

Customer Reviews

Based on 55 reviews
Excelente calidad

Llegaron a casa con bastante rapidez (España) los jfet y las PCB para montar un aleph J.
Como siempre, muy contento con la calidad del material además de la cantidad de información y facilidades para el montaje que facilitan muy amablemente desde diyaudio.

Aún estoy en el proceso de montaje en un chasis 4U, pero aquí dejo alguna foto (iré publicando mas a medida que vaya avanzando).

Matched JFET K170 J74

Very high quality JFET. They were set to run class A in the F6 amplifier, run very hot but without heat sink. I nearly run all day, every day in the Summertime, they still alive. Now, for saved money, I added a small fans for them. Excellent sounding, no noise can be heard at all. Thank you very much.

Absolutely Good

Hello I have bought them to build the "Boozhound Laboratories Deluxe JFET Phono Preamp". I have just soldered them, check the DC biasing and it was everything perfect according to spec. NO troubles. Sound is great and clean. Noise is very low.
It was a good service.

Otherwise happy

I ordered the LSJ74/LSK170 matched octet and I am happy with how my B24 amp sounds. Despite the long delays on the stock, there was some hiccups with the delivery to South Africa but once that was sorted out it didn’t take more than 3 days until the order was in my hands. I am happy.

Very satisfied !

Perfect matched transistor with a long lead time (6 weeks)
Already in use in my F5 with very good results

Measurement will come very soon online

Matched quad of lsk170--is it cost-effective?

Well, yes, it certainly is. You can buy 20 lsk170 from somewhere or another for say $40. Match them yourself. That is what I did. Guess what? Out of the whole lot only two were well-matched. So, yeah, $29 for 0.1mA quad match is a very good deal, indeed.


Linear Systems Matched JFETs

Quality components - prompt delivery.

K170, J74 jfets

Perfect service - good quality products, fast delivery.

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