Search found 3705 matches

by JR.
Thu Feb 08, 2024 12:42 am
Forum: Pro Audio Design
Topic: Spring Reverb Preemphasis
Replies: 5
Views: 1355

Re: Spring Reverb Preemphasis

Springs have odd overload characteristics, I'm not sure how much pre-emphasis they would tolerate.

Companding NR has difficulty with the spring reverb tail altering the expansion decode accuracy.

JR
by JR.
Sun Feb 04, 2024 9:15 am
Forum: Document
Topic: 9 Volt Battery End of Life Voltage
Replies: 4
Views: 9832

Re: 9 Volt Battery End of Life Voltage

Thread from the past. I'll add to the dataset that 7.6V is the end-of-life voltage for a Zircon water leak detector. It reached end of life around 12:30 AM this morning and began beeping. I have about eight in the house - two in the kitchen. This one was behind a snap-on kick panel underneath the s...
by JR.
Wed Jan 31, 2024 3:16 pm
Forum: The Peabody Lounge
Topic: John Roberts' audio articles
Replies: 16
Views: 12034

Re: John Roberts' audio articles

It's 20 uH 22 Ohm min or 25K max and yes its 1.6 kHz but as I point out the Q is nada at both extremes. my bad, I don't do much work with inductors, [brain fart] I used the relationship for caps in series. It introduces a nice HF gain rolloff. Joe Neil in Waynes mic pre used them IIRC at max gain t...
by JR.
Wed Jan 31, 2024 12:11 pm
Forum: The Peabody Lounge
Topic: John Roberts' audio articles
Replies: 16
Views: 12034

Re: John Roberts' audio articles

I don't recall adding those inductors myself or why there are two of them. Perhaps one at each transistor emitter. Surely to reduce RF gain and rectification susceptibility. (I had a junior engineer doing the detail work). The R is never 0 Ohms but 22 ohms minimum/25k max, the L is 5 uH (two 10uH in...
by JR.
Tue Jan 30, 2024 10:30 am
Forum: Pro Audio Design
Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
Replies: 41
Views: 17111

Re: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"

Interesting but is side chain signal rectification the significant audible concern in side chains? In dynamics processing there are multiple moving parts. Too fast release can cause visible distortion on LF content, too slow attack can allow overshoot, etc. There are multiple strategies to mitigate ...
by JR.
Mon Jan 29, 2024 1:00 pm
Forum: Pro Audio Design
Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
Replies: 41
Views: 17111

Re: A Quadrature Power Summed Compressor Sidechain

I looked into this concept for reducing ripple in low distortion sine wave oscillator AGC ( a long time ago). A SVF topology for the sine wave oscillator provides the quadrature sine waves. I recall trading some notes with Brad (RIP) so this concept has been kicking around for some time. IIRC he sha...
by JR.
Sat Jan 27, 2024 11:26 am
Forum: The Peabody Lounge
Topic: John Roberts' audio articles
Replies: 16
Views: 12034

Re: John Roberts' audio articles

I am still embarrassed that in that article I spelled bus wrong. Were you trying to look good for some British gal? I recall mentioning to the editor of Studio Sound while I was visiting in London back in the 80s that the "buss" spelling was a Brit affectation. He was visibly upset and ar...
by JR.
Fri Jan 26, 2024 1:51 pm
Forum: The Peabody Lounge
Topic: John Roberts' audio articles
Replies: 16
Views: 12034

Re: John Roberts' audio articles

Thanks guys... I have hosted a copy of my console performance limits design article on my web hosting area. http://www.johnhroberts.com/des_art_1.pdf I am still embarrassed that in that article I spelled bus wrong. I also have a list of my patents here with some brief descriptions http://www.johnhro...
by JR.
Thu Jan 25, 2024 5:39 pm
Forum: The Peabody Lounge
Topic: John Roberts' audio articles
Replies: 16
Views: 12034

Re: John Roberts' audio articles

Sorry no... Besides my several kit articles in Popular Electronics, I wrote a column in RE/P magazine for a few years called "Audio Mythology". While working inside Peavey I wrote multiple articles for Peavey's dealer Magazine (Monitor). I even wrote a health column for the in-house Peavey...
by JR.
Wed Jan 24, 2024 3:18 pm
Forum: The Peabody Lounge
Topic: Ok, now they are just trolling us
Replies: 5
Views: 4054

Re: Ok, now they are just trolling us

renders now.... "scientists warn to not believe everything you read"... :lol:

JR