Pro Audio Design Forum

The layout for the Quadrature Summing Filter checks out. https://proaudiodesignforum.com/images/jpg/Quadrature_Summming_Filter_PC_Board_Assembled_1200.jpg Quadrature Summming Filter PC Board Assembled https://proaudiodesignforum.com/images/jpg/Quadrature_Summing_Filter_Red_Blue_L_Plus_R Green_Pink_...

I decided to revisit the argument I've previously made regarding the 1/f noise effects of having input coupling capacitors versus direct-coupling of mic preamp inputs. I decided to use the Flat Moving Coil Preamp since its a finished circuit board. The input noise voltage is exceptionally low, at a...

Bombshell Vax Analysis Finds $147 Billion In Economic Damage, Tens Of Millions Injured Or Disabled A new report estimates that 26.6 million people were injured, 1.36 million disabled, and 300,000 excess deaths can be attributed to COVID-19 vaccine damages in 2022 alone, which cost the economy nearl...

"Don't Let Them Get Away With It"

Video: https://waynekirkwood.com/content/Dont_ ... ith_It.mp4 (4 min)

SARS-CoV-2 requires acidic pH to infect cells Interesting article: "SARS-CoV-2 requires acidic pH to infect cells" (pdf): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9499588/pdf/pnas.202209514.pdf Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cell entry starts wit...

I should be receiving boards Tuesday.

More sound files. Davie Allan and The Arrows "Shape of Things to Come" originally recorded in LCR. Sequence is Stereo, L+R then I+Q. https://proaudiodesignforum.com/content/Quadrature_Summing_Filter_Davie_Allan_Shape_Of_Things_Demo.wav https://proaudiodesignforum.com/images/jpg/Quadrature_...

While I'm waiting on Quadrature Summing Filter boards to be delivered I fired up the Protoboard to make some sample files. Some time ago I downloaded a problematic synth sample from Gearspace that was posted in this thread: https://gearspace.com/board/so-much-gear-so-little-time/1137281-mix-element...

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...