Pro Audio Design Forum

Quadrature Summing Filter boards are on order and should be available in about 7-10 days.
I'll be building one to check the layout as soon as they arrive.
The BOM for parts excluding PC board looks to be about $101 US.

This is the current schematic for the "Quadrature Summing FIlter" layout. I decided to eliminate the ability to route the separate I and Q components to the final outputs to save a relay and board space. This mode would not be used in most applications. I and Q now come up on a header whe...

Putting the final touches on the "Quadrature Summing Filter" board. https://ka-electronics.com/images/jpg/Quadrature_Summing_Filter_PCB_Layout.JPG I eliminated the relay which forwarded I and Q as "stereo" to the final output. That would almost never be used except for people wa...

I used to use duckduckgo all the time and simply overlooked them.

Duckduckgo ties with presearch.

I've done screen captures of all of them including duckduckgo that I should post.

Search Engine Performance Rankings I just did a quick test of search engines. Google came in dead last. The search term was for an article posted here on March 14, 2022 that has been viewed about 2200 times. I used the term "Component Matching Minimizes IM Distortion in the Demrow-Cohen Balanc...

Digi-Key Now Stocking Linear Integrated Systems Not sure when Digi-Key became a Linear Integrated Systems distributor - they're not listed on the Linear Systems website. https://www.digikey.com/en/supplier-centers/linear-integrated-systems LSK170: https://www.digikey.com/en/products/filter/transist...

Alps Potentiometer Taper Chart

I'm always having to look this up and Alps keeps moving the link...

Florida Doctor Removed from Hospital Board Meeting After Testifying on the Effectiveness of Ivermectin to Treat Covid On Tuesday, a Florida family medicine doctor was kicked out of the board meeting after testifying about the effectiveness of Ivermectin to treat COVID-19. Dr. John Littell, who serv...

Looks like Mouser has some inventory of TDK CUT35: https://www.mouser.com/c/?q=cut35

They're functionally very similar.
I think the advantage of the Birt using op amps is that it is lower cost and not single-sourced.
For DIY there is also the through-hole advantage.
The overall CMRR performance of both is limited by the resistors.