I've been working with internet radio for a while and would like to share my recommendations. Enjoy and feel free to ask questions or add your own insights.
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This is valid for shows with up to 4 hosts and a really professional broadcast sound on a budget.
Here's the cabling diagram (5000x5000 px):
http://img27.imageshack.us/img27/1069/podcastgear.jpg Rode Podcaster in shockmount an mic boom -> SM Pro TB202 (or TC 202 for more compressor parameters)
This gives you plenty of gain (needed for dynamic mics), a warm sound and a rather nice compression for talking. Use TC 202 if you're comfortable with using a compressor, it's a bit more expensive but has the usual compressor parameter instead of an EQ.
SM Pro TB202 -> Allen & Heath ZED 14 Input 1-4
The SM Pro Preamps are 2-channel units (more or less equivalent two channel strips in one) are plugged into the line inputs of the Mixer. You can add some more gain using the mixer's gain knobs, and EQ it to make your voices sound nice.
Skype -> Allen & Heath ZED 14 USB (channel 13-14)
In Skype for Windows and Mac you can select the input output and ringer devices. If you want to take calls during your show/podcast, I recommend settings Skype's input and output to the ZED 14's USB interface. This way, you have a dedicated fader for Skype and can choose what channels you want to go to Skype.
When you get calls over Skype, they're usually way too loud or barely audible so the fader really helps to level it out. Skype only does mono and ignores what comes in on the right channel, so set AUX3 on the mic input channels to 0dB (9 o'clock on this mixer) so the caller can hear you. Don't forget to depress the "AUX 3-4" switch so the AUX sends are routed to USB (Skype), leave the "AUX 1-2" and "LR PRE" switches disengaged. You DON'T want to route the Main Outs to Skype, because that would get you terrible delayed feedback.
If you wan't the Skype caller to hear your music or jingles, turn up the AUX3 knob on the PC channel (11-12). Maybe don't turn it up to 0dB but a little less to make sure the caller can clearly hear you talk over the music. If you want to ridicule your caller by playing fart sounds or having a co-host make fun of him without the caller knowing, turn down the AUX3 all the way down on the channels you don't want the caller to hear. ALWAYS keep the AUX3 on the Skype channel (13-14) all the way down, otherwise the caller will hear himself on an annoying delay.
If you're doing a show where you want to take random calls from listeners, it's a good idea to have the Skype channel muted on the mixer and set Skype to auto-accept all calls (and set Skype up so it doesn't make ringing noises). This way, when people call, they immediately hear the live show (remember that streams on uStream, Stickam or any other service are on a significant delay) on Skype and If you wanna take the call, just unmute the Skype channel and say something like "you're on the show" and adjust the fader to a comfortable level.
Behringer Autocom MDX1600 on the Main Mix
One of the cool things about the Allen & Heath ZED mixers is that they all have inserts for the Main Mix. Although your mics are all individually compressed, their volumes still add up if more than one person is talking at the same time or someone's talking over music. Music is also mastered on different levels (old music is quieter, Hip Hop is way loud, indie music all over the place). Jumping volumes is highly annoying for listeners so having a compressor/limiter on the main mix is a good idea. Any stereo compressor/limiter will do but the Behringer is as cheap and totally up to the job. Go easy with the noise gate and use the "Peak Limiter" to get the levels up. If the Mixer's VU-Meters yellow lights never light up and the 0 dB light occasionally lights up whether you're talking normally or yelling over music, it's just right. Press the "Couple" swith on the Behringer so you just dial in your sound on the left half of the unit and it will be stereo.
If you're using a different mixer without main inserts, just connect one output pair of the MDX1600 to the audio interface and the other output pair to the headphones amp. In that case you need to set the input levels on the interface itself and your main output level meters are on the Behringer, not the Mixer.
Behringer HA4700 headphones Amp
This thing has 4 outputs with a Bass and Treble EQ per output so you can compensate for cheap or different headphones. Either connect the headphones amp to the Compressor/Limiter on the Main Mix (the MDX1600) or to spare main mix outputs on the Mixer (provided it has Main Mix inserts like this ZED14).
You could have multiple headphone mixes using the mixer's AUX sends but that's rarely necessary for radio. If you have a dedicated DJ/Prodicer, you could turn up the AUX1-2 knob on the PC channel (11-12, where the music comes in) and mix in the microphones and Skype channel just a little. This way, the DJ/Producer can pre-listen to the music or jingles without the hosts hearing it. AUX1-2 are pre-fader and the host of the show would need to turn down the ch11-12 fader all the way down when not playing music. The Mixer's AUX Send 1-2 need to be connected to an AUX In on the front of the Headphones Amp via a Y-cable (TRS on one end, two mono jacks on the other).
Tascam US 100 Audio Interface
Now this is a rather low end interface but it uses the default system drivers (ASIO on Windows or CoreAudio on Mac) so you won't have troubles with outdates drivers or software not working with it. It only has RCA inputs but those are fine, just connect it to the 2-track input and output of the mixer. The signals going into it are already heavily compressed, so 16 bit is totally adequate and 44.1 kHz should be used anyway. Set up your stream (and recording software) to the interface's inputs.
Headphones
I personally love the AKG K240 Studio because they're comfortable and not tiring after hours. Don't go for closed headphones, these are usually very tight on your skull and you don't have a click track or anything that you don't want to bleed into the mics. Any semi-open cans will do.
If you're really on a budget
- Only use one mic boom for the main host and use heavy table mic stands for the co-hosts, the ones with a heavy round base (like the K&M 232BK)
- Use one cardioid condenser mic for the co-hosts. You don't need to be so close to condenser mics so two people can share one. It will sound better than using two SM58 but you'll have some room sound coming into that mic.
- Use the Mixer's preamp if you can't afford the SM Pro stuff, you still need compressors though.
- If you can't afford the Headphones amp, the Mixer has two headphone output and most audio interfaces have one two. You won't get different levels though or get the main mix compression on all
- If you're only doing a one or two person show, you can get by with just one stereo compressor. In that case, just put one MDX1600 on the 2 mic channels and set it to limit a lot. Your music and jingles won't be compressed, but you can't have them both. If you just put a compressor on the main mix, either your music/jingles will be way too compressed or your voices will not be adequately compressed.
Behringer also makes 4-channel compressors (Multicom). They have less parameters and you could just use the first 2 channels on the mixer's channel inserts and the remaining 2 channels for main mix limiting.
- Use just one stereo audio interface. This will give you just one fader for music/jingles/skype but you can get by. You could also just have a second computer and use its built-in input and output for skype.