I know some of us design/build/repair electronic equipment and components professionally - I wanted to ask if anyone had used Linear Systems transistors - one of their JFETS was suggested to me for a preamplifier design and I wasn't familiar - was going to go with a Texas Instrument equivalent. Anyone have any experience with LS?

Maybe thread could be catch all for part/oem/supplier suggestions.

Force instance - I am ecstatic every time I use these Wago wire nuts, and have been over the moon when they started showing up at home depots. A simply better wire nut in every way:
https://www.digikey.com/en/products/det ... ZYQAvD_BwE

Those Wagos are the best. I keep one on my desk at work as a fidget toy.

I approached Linear Systems about performing automotive qualification on some of their parts when I was designing Mark Levinson amps. Ended up being too cost prohibitive and we went another direction, but their parts are highly regarded.

Nate Dort wrote: Fri May 06, 2022 7:22 pm when I was designing Mark Levinson amps.

oh do tell!

I was lead HW design engineer on the latest Mark Levison automotive amplifiers (Lexus exclusive) before I left Harman 6 weeks ago.

It's a 12 or 16 channels (depending on the vehicle), discrete Class D design. ~200 W / channel output. Frequency response from 0 to 40 kHz, +/- 0.5 dB.

I looked on ebay for a photo, but I'm guessing there's not a lot of wrecked 2022 Lexus NXs out there to pull parts from.

This is the last generation that I also had a hand in, circa 2017, before taking over the design and optimizing it for the 2022 model year:



Part of the Mark Levinson design philosophy is to be able to pass DC from the amplifier, to avoid phase-shifts. No DC blocking capacitors in the signal path.

Anyway, most of the Lexus systems use a digital input into the amplifier from the head unit. There's a small subset that use an analog input with an older communication bus technology. The analog version was the one I was looking at Linear Systems FETs for, to use in a discrete balanced-to-single-ended line input stage, similar to what they do in the $20k full-size monoblock amps.

Nate Dort wrote: Fri May 06, 2022 7:22 pm I approached Linear Systems about performing automotive qualification on some of their parts when I was designing Mark Levinson amps. Ended up being too cost prohibitive and we went another direction, but their parts are highly regarded.

ah! wonderful feedback thank you - I was feeling similar, I can't get the TI part so cost might not be a primary factor

Nate Dort wrote: Fri May 13, 2022 9:36 am I was lead HW design engineer on the latest Mark Levison automotive amplifiers (Lexus exclusive) before I left Harman 6 weeks ago.

It's a 12 or 16 channels (depending on the vehicle), discrete Class D design. ~200 W / channel output. Frequency response from 0 to 40 kHz, +/- 0.5 dB.

I looked on ebay for a photo, but I'm guessing there's not a lot of wrecked 2022 Lexus NXs out there to pull parts from.

This is the last generation that I also had a hand in, circa 2017, before taking over the design and optimizing it for the 2022 model year:

Part of the Mark Levinson design philosophy is to be able to pass DC from the amplifier, to avoid phase-shifts. No DC blocking capacitors in the signal path.

Whoa

Also - where are you now?

I switched industries and I'm working on battery management systems at a startup called Our Next Energy (ONE).

Nate Dort wrote: Fri May 13, 2022 11:06 am I switched industries and I'm working on battery management systems at a startup called Our Next Energy (ONE).

Feel free to give me a holler if something called "functional safety" gives you any trouble.

Nate Dort wrote: Fri May 13, 2022 11:06 am I switched industries and I'm working on battery management systems at a startup called Our Next Energy (ONE).

Very cool - if that doesn't tickle your fancy and you want to make dumb music things for less money and spend more on a house (in southern california) give me a holler.