Advanced Audio podcasting: Episode 1 - Buckets of money.

There is another level you can go for an audio podcasting studio.  One that takes advantage of used but High end DSP gear, this is not going to be speculation,  this is actually how I am building my own podcasting studio.  I dont have a lot of cash to just dump into a hobby.  And be honest, unless you are Leo Laporte or one of the guys that started podcasting early on and have a lot of sponsors throwing buckets of cash at you, this is a hobby to you.  There is nothing at all wrong with it being a hobby, it means you have a passion for it that makes every day you spend on it fun and enjoyable.

My design is based on what I have seen at modern radio stations, but leveraging modern teleconference technology.  I have been programming audio DSP devices for a few years and I really am impressed with the power these boxes have. These devices allow a corporate boardroom to sound like a professionally produced radio show without any effort at all on the users part.   Companies like BiAmp and BSS have incredibly powerful devices that after programming can do a lot of tasks automatically.  But coupling a Crestron control processor to the system allows even more automation and control.  If you were to buy everything brand new, you are looking at a $30,000+ studio.  But I am shunning anything new expect cables.  Everything I am using is considered to be "horribly out of date" as far as the industry is concerned, but it is still viable, useable, and absolutely perfect for the task I have for it.

What follows is going to be very high level.  You need to understand audio to replicate this.  you also need to be a crestron programmer to do the crestron control side.   you dont HAVE to use crestron,  it's what I know and bought the gear for next to nothing.  I am available to program and/or help but at a price that most will freak out at.

The DSP I chose was based mostly on price and then capabilities    ClearOne makes low end DSP devices and lose their value rapidly.  I choose the ClearOne XAP800 because it is absolutely dirt cheap now on the used market.  I paid $95.00 total with shipping for a unit that looked good and had no problems with it, these units went for $4,000 when they were new.  The software is still available online at the ClearOne website, you have to look for it and grab the latest, you might want to upgrade the firmware as well.  this has 12 inputs and 12 outputs.  These are MONO inputs, so stereo audio takes up two channels, the only thing you need as stereo out is the Recording output.  Everything else wire as mono.  Your mics are mono, Skype is mono, dont waste inputs or outputs with stereo.  I use the first 4 inputs and outputs for the skype computers (Yes computers, more on that later) then the next 4 for studio microphones (the 4 outputs for a set of headphones for each mic), 1 for an audio cue input, 1 spare, and then the last two for a stereo input from a digital "cart machine".   The last 4 outputs Two are studio monitor out and two are record out.  This is my setup, you might need a different configuration.  I want to have the ability to have 3 guests in studio each with their own mic and headphones.   I have a separate headphone out to allow each person to adjust their own level and feedback level.   It's important for people that are not used to recording or broadcasting to hear themselves, so you can send their own voice back into their headphones at a higher level than you are recording to make them more comfortable.

Lastly the 4 computer inputs and outputs,  Yes you can have all your guests and hosts on one skype call, and this works great.  Most podcasts are set up this way and sound great.  But it limits your ability to mute a caller that may have a problem, like one guest I had suddenly had a lot of HUM in his mic when he was not talking, if I was able to mute that single person easily the whole podcast would have sounded better. so I have 4 skype computers and call each guest and host separately  now their audio is separate and I can adjust it myself and control it.  being able to mute each guest easily is a benefit.  the DSP lets me mute them to the record input and the other guests while I can still hear them in my headphones.  Cant do that with a desktop mixer and a single Skype computer.  Now I choose to mixdown and record directly.  If I wanted to spend more time editing,  I would configure the DSP to output the audio of each guest and host to a separate output and record with a multi track audio recorder.  This lets you spend days cleaning up each persons audio to make them all sound as of they were in a $20,000,000 studio with you.  I do not have the time to mess with my DAW (Digital Audio Workstation)  for each episode, plus I can't afford an 8 channel digital recording setup.

Now I mentioned a stereo input for a Cart machine.  I personally wont use this until I find a real use.  I really hate the "morning zoo" format of podcast that is full of audio drops and sound effects.  I find it distracting and is usually there to hide the fact that the recording is chopped up all over the place.  I do see the need to playback to the podcast and the live hosts and guests a recording from earlier such as an interview with a guest that was unable to make the recording time and day.   This is my use for the input.  and I left it stereo just in case and I had spare inputs to use.  you could play your intro and extro live during recording this way, although it will add noise.  Every time you run audio through analog equipment you add noise. fire up the DAW and add the intro and extro, that only takes a few minutes and will give you a very clean sound.

You can stop here right now and use the ClearOne software to control everything,  I have personally discovered that there are two things that happen right away compared to using my Mackie mixer.  First the noise floor overall has dropped to -80.  I have no background noise at all being generated from the system, this is fantastic compared to the -50db of hiss that every mackie mixer I have ever owned has added to audio.  Second  the Noise reduction system built into the clear one as well as the Limiter built in really makes things easier to deal with.   I cant not clip audio from my side if I yell, laugh, etc..  Yes Skype has this built in, but only if you enable their AGC and this introduces a lot of added noise into the recording.  Skype will ramp up the AGC slowly until you get a LOT of background noise being pumped into the audio.   The one drawback is that in my headphones, I have a 15-30ms delay in the audio from what I say to what I hear in the headphones, so you hear a reverb from your own voice if you listen to the record output.   The reverb is not recorded, it's just an audio effect in your head as the sound from your mouth hit's your ears before the same sound comes out of the headphones.  This is really not a problem, it's just an annoyance.  if you use the headphone out you can reduce your own voice feedback to limit this.

My next step is to make this easy to control.  For someone else to do this on their own will be difficult as it requires that you have knowledge of the hardware and access to the programming software.   Crestron software is only available to Dealers and CAIPS,  No I cant give you a copy.   There are other options for control other than Crestron.  I start with a used and dirt cheap CNMSX-PRO processor.   I don't need the pro, I can use pretty much any of the old SX line processors (Or 2 series, but those are far more expensive) but I was given 3 of these SX-PRO processors for free along with a VT-3500 touchscreen and several CT-1000 panels.  You don't need to use what I am using, there are other panels that are cheaper smaller, etc.   I also have a Telephone interface board in my Processor so I can create "cue tones"  such as a timer that goes off every 15 minutes that plays a beep in my headphones only to remind me to do a "station id" in the podcast as well as a end of podcast notification at 55 minutes.  as well as timers counting down on the screen of my tocuhpanel.  I can even set off a blinking red light if I wanted to from the relays on the processor.   The point of the Crestron is to make the system "brain dead easy" to use as well as give some features that you would have at a radio station. My goal is a setup  that anyone can sit in my chair and record a podcast without any training at all.   The Crestron also will allow me to "reset" the DSP to default settings at the push of a button the advantage is that if I had to adjust things drastically for a show where I had a very quiet talker in studio and a loud one on skype,  a single button press brings everything back to a normal state without having to remember that I adjusted things 2 weeks ago.   Having a touchscreen for any guest in studio to adjust their headphone volume or even mute their mic for a "cough" is a good idea.  Don't send them cue tones as it will confuse them.

Recording or more specifically backup recording is accomplished by a used TEAC CD recorder.  I actually have 3 recording devices running on every show.  I stopped recording on the PC due to software being less reliable.  So I record to a digital recorder, a DAT recorder and a CD recorder.  All except for the digital recorder were bought used off of ebay or craigslist.  The 8 track DAT recorder I have is actually from a friend that cost me a 6 pack of  craft beer.  Having lost an incredibly good podcast with a guest that is well known, I had to make sure I can't lose a recording ever again.  I may have went overboard with redundancy, but it's worth it to my peace of mind.   The CD and the digital recorder record in stereo.  I keep all CD's I record as archival and they are cheap. Audio CDR's are $0.15 each.

Lastly on the hardware short of your microphones,  The Skype PC's.  you don't need a lot, Skype wants a single core 1ghz processor and 2gb of ram.  You can get mini fanless pc's (fanless for less noise) for less than $200 each from newegg that are dual core and 1.8ghz.  add some ram and the smallest SSD disk you can find. all you need in these are the OS and Skype.   Going linux as the OS is a benefit as you dont have to pay for Windows.  IF you set up each skype PC right you can then leave them without monitors and connect in over the network remotely to manage and start the calls.

Next we will talk about interconnection and setup as well as where do you put all this stuff....


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