[Elecraft] [KX3] Using a Sound Card for Mic (Multiple) Input(s)

[Jim Brown]

On Sat,5/28/2016 5:45 AM, Joel Black wrote:
>
> I currently have a Focusrite 2i2 I bought after my E-MU 0204 stopped working in OS X 10.11. It has two inputs and two outputs. Experimenting the other day, I tried using my MH3 mic on the input to the sound card with the sound card output going to the MIC IN on the KX3. It didn’t work. I then realized that the MH3 is a condenser mic and needs to be powered. The 2i2 has a “48 V phantom power” switch, but I am a little nervous of turning that on. I don’t want to let all the “magic smoke” out of my mic.

48V phantom power is exclusively for BALANCED mics wired from PRO use. 
It does NOT work with the unbalanced electret mics we use with our ham 
gear, and it would almost certainly fry them. The "bias" that we use for 
unbalanced mics fulfills a similar function, but the two methods and 
kinds of mics are incompatible.

> After all of that, I began remembering an issue I had with a Genesis G59 SDR I built several years ago - the delay in the route from audio in to the sound card, the sound card input being processed by the computer, the computer outputting that data to the transmitter. It was quite reminiscent of my days operating the HEO satellites. The delay is unnerving and I have never been able to compensate for it other than turning off MON. I’m supposing I’ll have the same delay if I incorporate a sound card for multiple inputs.
>
> Would I be better off just adding a mixer?

You haven't said what you want do do that you can't do with a mic and a 
sound card, and what you expect a mixer to do. I strongly recommend that 
you avoid a mixer. Far better to plug and unplug if you need to -- plug 
in the mic for SSB, plug in a cable from computer audio for digital modes.

BTW -- the need to plug and unplug is one of the shortcomings of the KX3 
(and KX2) as compared to K3/K3S. With the K3/K3S, you can leave 
everything plugged in.

I do NOT recommend a mixer -- too many complications with hum, buzz, and 
RFI and getting levels set right.

73, Jim K9YC