Pro Audio Design Forum

The designs I did, typically delivered a differential AC current output and relied upon a real resistor hanging between pins 2/3 effectively in parallel with the 2k or so mic input termination to convert that current to a voltage... Increasing C load, just shifted the LPF pole frequency downward. Th...

nice job...

JR

I am pleased to make it through april 1 without fooling or being fooled...

JR

I'm not loving it... Lots of parts to make what is essentially a unity buffer (OK + 6dB with signal splitter). I'd be tempted to use less I uF caps, and maybe throw in some voltage gain, but I don't know how hot that capsule output is. Worth looking at, not sure it's worth copying... I played around...

Sorry I haven't been paying attention to what you are capturing the audio for. A/D specs inside micros have some specific gotchas. The micro family I use, provides info on internal parasitics and impedances. Basically your source impedance, must charge up (or discharge) the A/Ds input hold cap, so t...

I don't think he needs to go that far,,,he's probably just citing the driver data sheet numbers. I2C and SPI are generally included in the firmware for popular micro's while i rolled my own SPI once to deal with circuit issues in one design. When mixing digital poop with high performance audio poop,...

Are the TL074 buffers needed? You can use a simple resistive pad to drop levels down to 3vp-p. I guess it's nice to isolate the audio sources. If the A/D inputs are multiplexed (they usually are) their S/H capture acquisition can talk back into the inputs, and settling time for the S/H will affect c...

I pretty much ignored the 49 ohm R since I never found much use for a balanced input to differential output circuit. I typically used that topology to single end a balanced feed coming into a console or rack gear, and since it would be lightly loaded by the following stage there is little need for b...

Sorry to jump into the tail end of a conversation. http://www.ka-electronics.com/Images/jpg/Birt_Line_Receiver_ADI-Jung.jpg +1 to the suggestion to add LPF caps across R2 and R4. These caps need to be same value and similar precision to Rs for HF CMR, while 1% caps are surely rare. R7 is only useful...

Funny I still have some inductors back in my lab I bought to build a 5 band GEQ from a kit in popular electronics back in the '70s. I never built it or any Inductor based EQ, and don't even like the common gyrator based EQs (gyrator as shunt to ground between opamp + and - inputs). If trying to recr...