Pro Audio Design Forum

Thanks Roger.

I still need to prototype the AD797 version to check stability. It will quite likely have a 619 ohm and a 1K5 Rfb network.

Ohhhhhhhhhh... you were talking about records...

Ha! No, what I meant to say was black leather. Sorry, my bad.

I'll dig for it.

There was a PAR article about DSP vs. Analog summation about a year ago. The guy that wrote it - and I'm paraphrasing a 4 page article - basically said that DSP-based mixes had a very narrow "fader" sweet spot. His opinion was, after doing the same mixdown both ways, was that analog soluti...

Thanks John for the post and info.

But as you know I have a better plan for high performance summing.

Yes I do. I'm looking forward to that. We all are.

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 ...

Yes Roger Rbias will factor into the precision of the attenuator as the pot (or switch) is rotated towards the -3dB position. And, it will shift the 0 mark as drawn. Consider that portion visual short-hand. I originally considered using two Rbias resistors. Both connect to the wiper. One connects to...

I decided to prototype a quick +3 dB gain stage with a 5534 to check the resistor values. With 6K19 and 15K at their ideal values we hit 3 dB within 0.08 dB. I confirmed exactly 3 dB via measurement. THD isn't bad although I really don't have the instrumentation to measure beyond 6KHz. Near the clip...

In the above drawing it's not clear whether the AD797 is inverting or non-inverting. It's non-inverting Paul. So there's no additional re-inversion required. Because it's non-inverting, the CM performance of that stage requires careful op-amp selection. That's why we looked at the AD797 vs. a Natio...

Have you looked at the moon recently?

Here's the view from Australia. In the northern hemisphere it's inverted.



http://www.theage.com.au/national/smile ... -6p8d.html