Search found 3702 matches

by JR.
Tue Mar 12, 2024 2:16 pm
Forum: Build
Topic: Phono Transfer System Construction Information
Replies: 244
Views: 6202575

Re: Phono Transfer System Construction Information

IIRC the IEC proposed a real pole at 20Hz (7950 uSec) back in the 80s (?). The RIAA dismissed that suggestion and left the sub 20Hz response pretty much undefined beyond the three standard RIAA time constants (75uSev, 318uSec, 3180uSec). Back in the 80s when I was trying to escape from the audiophil...
by JR.
Mon Feb 19, 2024 11:47 am
Forum: Pro Audio Design
Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
Replies: 35
Views: 14921

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

One thing I'm going to change is the gain control of the capacitance multiplier. The pot is too cramped at slow rate settings and most people would want stepped controls anyway. Switching input resistors on the inverting stage to use a 6 position rotary switch with 600, 480, 360, 240, 120 and 60 dB...
by JR.
Sat Feb 17, 2024 8:47 am
Forum: Pro Audio Design
Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
Replies: 35
Views: 14921

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

Over the years, often working with inferior gain elements, at least part of the effort was to mitigate sudden gain change artifacts. The pan between dry and full gating helped coax out subtle flaws. The problem was flaws heard with complex (music) waveforms that weren't heard with standard test sign...
by JR.
Fri Feb 16, 2024 10:08 am
Forum: Pro Audio Design
Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
Replies: 35
Views: 14921

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

Back when I was seriously designing dynamics processing circuits a homemade tool that I found useful was a variable tone burst circuit. Sorry if I've shared this before, the drawing was done in 2007 and I designed this back in the 70s/80s. The bottom section generates adjustable on time and off time...
by JR.
Tue Feb 13, 2024 1:19 pm
Forum: Pro Audio Design
Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
Replies: 35
Views: 14921

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

Getting a little esoteric is there any risk of making compression too clean (i.e. having no sound signature)? Back in the 80s when I was tweaking companding NR my goal was to be as transparent as possible. Modern compression customers may have preconceived notions about what compression "should...
by JR.
Tue Feb 13, 2024 10:18 am
Forum: Pro Audio Design
Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
Replies: 35
Views: 14921

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

Lower distortion should always be good.

Does it impact the waveform distortion caused by fast release on pure low frequency tones?

While it is unclear that this mechanism is an audible problem with real world complex waveforms.

JR
by JR.
Thu Feb 08, 2024 2:08 pm
Forum: Pro Audio Design
Topic: Spring Reverb Preemphasis
Replies: 5
Views: 1148

Re: Spring Reverb Preemphasis

yup... the "boing" is the odd overload artifact I was referring to.

JR
by JR.
Thu Feb 08, 2024 12:42 am
Forum: Pro Audio Design
Topic: Spring Reverb Preemphasis
Replies: 5
Views: 1148

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: 9614

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: 10998

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...