Professional Audio Techniques; Taking your Podcast to the next level.
by David Fisher (www.whatisnoise.com)

David Fisher on Twitter: @Tibbon

Got a Podcast? You know the basics, now come learn to do things faster, more efficiently and best of all how to make it sound more professional.

David Fisher’s presentation was a list of 12 items for experienced podcasters to improve their audio. This wasn’t for beginners, as you needed to have a basic understand of audio to fully get the ideas that he was putting forward.

1. Quality microphones last a lifetime
   You should consider using condenser microphones when possible, but plenty of dynamic mics are available that are good too. Amongst those are the Electrovoice RE-20 and the Shure SM-7B. Both are used in broadcast studios and considered stand microphones to use. There are bargain microphones that are good available, but you run the risk of getting what you pay for. This happens specifically with tube microphones. Poor build quality and poor parts are used to make the microphones so cheap. There are techniques to know and learn as well. Specifically the proximity effect was mentioned. The proximity effect has an effect on the low end of the recording the closer you get to the microphone. The closer you are, the more bass comes through.
2. Use a hardware compressor
   A hardware compressor is preferred to a software compressor. Compressors help deal with dynamic range of the audio, and putting it into the signal chain as a hardware compressor, you are dealing with the dynamic range before the sound is recorded. To take a step back, compressors level out the sound specifically reducing the peaks in the audio. The downside to using a hardware compressor is that they could be difficult to use while field recordings, they can be expensive and once you compress something while recording it, you can’t uncompress it if you get it wrong. David suggests FMR Audio’s Really Nice Compressor for a moderately priced compressor.
3. Preamps matter
   Every recorded signal uses a preamp from the Flip camera to the highest end recording board that exists. Each preamp adds certain details and nuances to the recording. When only recording voices, you don’t have to go overboard with purchasing a preamp. There are deals to be had with preamps like microphones, but the same dangers lurk. David had a nice food analogy when it comes to preamps. Picture your recording as a piece of food. You can cook it many different ways. There’s a BBQ on a charcoal pit, or there’s the microwave. Each different way you cook/record, you’ll add certain characteristics to the food/recording. Choose wisely.



4. Do not over deaden your room
   There’s a difference between making a room quiet and making a room dead. When you put acoustic treatments on the walls of a room, you aren’t quieting noise you are deadening the room, specifically the reflections in the room. Some treatments might be needed in a room, but you don’t need to kill all reflections. Symphony hall in Boston is arguably the nicest sounding room on the planet, and the room is not dead. As a matter of fact, it’s quite alive with reflections. For an example of a dead room, go to your closet and speak while it is full of jackets. That’s a dead room.
5. Workflow is king
   Make sure to do it right the first time. “I’ll fix it in the mix” is an excuse for poor recording and it will take you longer. Keep extra sets of supplies around like batteries or SD cards. If it doesn’t get recorded because you weren’t prepared, then the sound quality doesn’t matter because it doesn’t exist.
6. Get a second set of monitors
   David suggets getting one full range set of speakers and one consumer level set of speakers. It always makes sense to listen to your work on something your consumer will listen on. Switches exist so you can easily switch the sound back and forth. Personally, I don’t think that you need a full range set of speakers. One set of bookshelf speakers and one set of crappy speakers will probably be what you need. David suggest brands like Genelec or Yamaha for the full range and speakers like NS-10s for the consumer speakers, but I suggest something like the Audioengine A2W or A2B for the high end speakers and whatever you can buy at CVS for the low end stuff.
7. Use a pop filter
   Pop filters assist with quick bursts of air. It helps with plosives (what’s a plosive?) Metal pop filters work better and are easier to clean, but are also more expensive.
8. Do not overdo anything
   Too much of anything can be bad when it comes to recordings. Don’t put too much gain on something or you might clip the signal and create distortion. Also, if you over EQ something, there are aural side effects that are difficult to predict, specially when it comes to compressing the file to be an mp3. A general rule is that if you need to turn something all the way up, there is most likely something wrong. An exception to this are the recommended microphones from earlier. The SM7B and RE-20 microphones are not that sensitive and you might need to turn them up almost all the way to get a decent signal from them.


photo by gomem

9. Room tone
   What is Room Tone? Record room tome for about 45 seconds to fill in potential audio gaps in the mix. Room tone can help smooth transitions or if you gate the sound too heavily, room tone can help fill in the silent gaps between phrases. Again, this is something that you should address before the recording, not afterwards. If it’s possible, make the room more quiet instead of processing the sound even more after the fact.
10. Mix into a compressor
    David suggests a high threshold, low gain make up, fast attack, slow release and a high compression rate nearly to the point of limiting. Did all that go over your head? I’ll translate from audio geek to human. The compressor should be set so that it doesn’t kick in too low. It shouldn’t be working all of the time, just with the louder points of the speaker’s voice. When compressing, don’t turn the gain on the compressor too high, because that’s an indication that you might be doing something wrong. No signal should need a whole lot of gain after being compressed, but it might need some. The compressor should be quick to reduce the speakers voice when it is reducing the volume, but it should also slowly bring the volume back in as to not sound too unnatural. When compressing, make sure that the rate of compression is high, so you don’t distort or clip your mix. By compressing it so heavily, you can make sure that the voices on the recording are audible the entire time.
11. Don’t recompress mastered audio
    David rick rolled us to start this out. But he does make a point. When a musician finishes a song, they compress it pretty heavily. When you bring that song into your podcast, and compress your podcast you run the risk of destroying the sound of the music. It’s not the absolute worst thing in the world, but it’s something to keep an eye and an ear out for.
12. Find a good audio dealer
    Working with a dealer will allow for easy returns and most dealers will allow trusted customers to borrow equipment for periods of time. Another point is that most audio equipment will cost exactly the same everywhere. Instead of looking for a deal, you should look for good service and a good relationship. While David suggests using someone local, I’ve had great experiences with Sweetwater in the past. I won’t go on further about them, but they are a reliable company and their tech support is great. If you do decide to buy anything from Sweetwater, tell them that you referred by Walt Ribeiro. Walt’s a great guy and turned me on to Sweetwater.

After the list was complete David took some questions from the audience. The first question was about tracking down hum. The answer given was to simplify your audio chain in order to figure out which piece of gear it is that’s giving the hum. Check that audio cables aren’t running in parallel with power cables, as that can introduce hum. If you can, you want to make sure everything is plugged into the same circuit as well so any voltage variations one piece of gear gets, they all get. You can regulate the voltage with a surge protector, universal power supply or a power conditioner.

The second question came from someone who is doing a tour of baseball parks and is concerned about the crowd noise causing digital distortion in the recordings. David suggested looking for a small compressor to put into the signal chain to reduce the signal. You can also record at a low level and amplify it later. In terms of recording in this situation, it’s better to record low then to record high.