Hey there - first time posting, long time soldering.
Just wondering if anyone has any experience with the SSI2164/V2164 chips and could help me wrap my head around a question I have about best practices around the audio input.
Basically, my question is whether it would be necessary to place an op amp buffer before the mixer IC when using it in the basic mixer config detailed in the manual - if so, what does this look like? Apologies in advance if this should be obvious but I'm struggling to find much information on the subject.
(https://i.postimg.cc/hJcyNWR0/Capture.png) (https://postimg.cc/hJcyNWR0)
Hi & Welcome.. :icon_wink:
Op-amp buffer should be essential only in case of VINs unequal signal output impedances..
(for equal signal mixing..)
Welcome!
As long as whatever you're feeding into it can cope with the 30K input impedance, you're fine. If for some reason you need a much higher input impedance (like 1M) then you'd need to add a buffer in front.
Note that the SSI2164 uses different resistor values from the other varieties of this chip (AS2164, V2164, and the original SSM2164). They halved the value to 15K for noise reasons, iirc.