Pro Audio Design Forum

I am reluctant to undertake a significant analog design project when in theory digital signals can be combined with no degradation, in fact after combining digital signals you get too much good information and some must be discarded. The analog console company I worked with on the meter project have...

Another compensation question for you John: Some time ago I saw a schematic for a distibution amp and in it they had used a 5534 as a polarity inverter with a signal gain of -1. It was an internal stage without external loading (cable). IIRC the Rin and Rfb were 10K. What was different about it was...

A capacitor across the feedback R can be compensated nicely by a similar C to the positive input (assuming Rs at both inputs), a C from the - input to ground is not the same animal. In fact a C to ground can generally be compensated for with a C across the feedback R. These Cs form a parallel feedba...

mediatechnology wrote:The best cities for dining?

Consider Tempe, Arizona....

http://www.heartattackgrill.com/

Profiled on this morning's CBS Sunday Morning with Bill Geist having the "quadruple bypass."

I like the side "dishes" but those burgers are just wrong..

JR

I generated a video of the Pk/VU meter.

I added another feature, there's now a peak hold on the top red LED and it triggers from peak level, even if meter is in average only display mode.

http://www.johnhroberts.com/Candy.wmv

music is by an old friend of mine

JR

I feel like I can design around the capacitance... and in a large console you might need to accommodate a lot of inputs... I don't know what it's like these days but I did one console with some 120 inputs to L/R and I doubt it was the biggest around. So the difference between 3 pf and 15pf is 5x but...

I guess I could look this up, how does the noise floor compare for newer small geometry VCAs versus previous stuff? If I was trying to market a stand alone mixer, noise floor would be a metric of interest to buyers, even though I've been saying for decades the bus noise floor will be dominated by on...

The VCA distortion will surely be uncorrelated since the individual audio inputs are all uncorrelated. The distortion should be the same as single VCA. I believe there is still a possibility that the individual input''s distortion might symmetrically cancel if a reciprocal topology VCA is used in th...

I believe I even said this in the almost 30 year old article, noise isn't the only or IMO primary benefit of this but OK... For 16 simple mono inputs, the conventional combining amp will increase bus amp noise 17x. Using VCAs you will see roughly 4x VCA noise + 1x bus amp noise (actually a little mo...

JR - Do you have a clean scan of that R/EP article you wrote? I think I have a copy that you sent but am not sure if I have the whole thing. Wayne http://www.circularscience.com/des_art.pdf I'm still hosting this scan on one of my websites. I'm not as organized as you about old stuff... I would be ...