Danny - I messaged someone who might know about all of this. He does video game walkthroughs on YouTube, with audio commentary.  He might know a thing or two about all of this. 

   -Mark

Headphones!

I think Lawdoginator is correct. It seems as though you're getting feedback using your speakers to microphone for your guests. Try using headphones and (if your audio hardware allows it) set your recording to "What U hear" mode. (Headphones may or may not need a mic).

I remember one recent show that Elliott was doing with a second host. The feedback and sound was awful. GM Hammer chatted about headphones, but Elliott didn't see how that could help and even thought it would make things worse somehow.

 

Well, finally Elliott tried the headphones and that cleared up everything. The sound was perfect after that. The difference was amazing. But Danny and David don't seem to believe in headphones. 

@Lawdoginator - I think Danny doesn't want to mess up his hairdo. ;) @Danny - Even guests that don't have a headphone and have their speakers too loud can give your voice an echo effect. Noise feedback on the internet creates an echo effect because of lag.

Yay! 

There is a type of earphones that are not apparent or visible to the audience:

e.g.: http://clarityoneaudio.com/Earbuds/EarBuds

I'm an audio engineer but I'm not sure from your post what you're trying to achieve or what the problem is.  Could you explain more about your set up?  What application are you trying to capture the audio from?  Mac or PC?  Basically we would need to follow the signal chain from your mic--analog to digital conversion--digital processing--audio file, to determine where the problem is.  I agree that headphones would be a big help to eliminate the feedback and bleed problems!  

All right! We've got an audio engineer agreeing with the headphones! 

The problems are (1) feedback and (2) background noise pickup.

Solutions are either (1) headphones (or earphones if you are aesthetically concerned) whose sound will not reach the microphones (2) or super-cardioid gunshot microphones whose pickup range will not permit sound bleeds from speaker (BTW, good-quality gunshot microphones are extremely costly, and you will need one per person doing the speaking).

even a good dynamic mic that you speak close to and set the recording level properly could work with speakers!  this is what live music recording is all about, dynamic mics with speakers everywhere!

Yes, but you cannot avoid reverberation with ordinary hyper-cardioid microphones - condenser gunshot microphones can even avoid that because of their extremely narrow cone of pickup (I had done on-stage recording once).

 

Use of wireless (or even wired) professional headsets (combining both earphones and close-range microphones) is yet another very good solution.

this is true but hyper-cardiod mics can be expensive, and gunshot are really expensive!  Also, I think the quality from a simple shure 58 would be really good!  But needs to go through a nice interface with good mic pre's!  What is Danny using now?

Hi Danny, you should contact Sourcefabric, they do open source broadcasting solutions and support. I'm actually considering them to set up a radio station. http://www.sourcefabric.org/

as far as mics go, all you have to do is go to control panel and choose mic boost and always use a mic like preuss has. A samson condenser is great. you should not get any feed back. If you don't have a condenser then you have to use headset..Daniel your audio always sounds fine, only one I can't stand is poets sound...lots of echo and preuss doesn't have to hold the mic so close. Those condenser mics are great at about two to three feet away. I am sure you are gonna find help but a lot of it is just testing. I talk all the time on the computer and I never have those problems. Go to control panel,sound, volume, advanced, check20db mic boost. If you don't have the mic volume bar then click on properties after entering advanced then check the mic box.

Just try the headphones. 

It is not dynamic or condenser microphone which is the issue - it is the "pickup pattern" which is important. It must be hyper-cardioid or cardioid - never omnidirectional. And should never have AVC (automatic volume control) turned on (this is a no-no in such "stage" recordings).

 

The search for "NULL" or "Virtual Cable" documentation means they are looking for a software solution of turning off mics not in use (whereas hardware solution is simpler with a DJ-class multichannel microphone mixer with slider pots, though initial cost is high).