Their requirements are between a -23db and -18db using the RMS (Root Mean Squared) measuring system with a -3dbTP max and your noise floor can not exceed -60dbs. The people who use Audacity seem to be having a hard time meeting these requirements. For some it has taken close to a year! In my opinion, it is more the fault of the software than the people doing the recording.
The largest factor is the that Audacity CAN NOT read the ASIO file that is supplied with Professional USB Audio Interfaces, you cannot review their stock filters/effects/plugins in real time and they are a 32 bit program. Regardless of how much RAM you have on your computer, Audacity can only use between 2 & 4 gigs MAX.
If you think my comments are a “Dig or Slant” towards Audacity, you are 100% incorrect. If you are new to Audio Book Recording then my goal is to give you solid advice. If you are a seasoned Narrator, you already know this. If you choose this profession to put food on your table then you need to embrace the Professionalism that will be associated with your decision. In 2017, anyone can spend less then $400.00 to create a Professional Recording Environment for the spoken word. 15 years ago, this would have cost you thousands of dollars!
In Podcasting, the number one question I receive the most is: “How can I make money Podcasting?” It is like any other business that makes money. It takes hard work, sacrifice, blood sweat and often tears! It takes education as well as the proper tools to get the job done in a professional manner. The sad truth in Podcasting is that only 3 to 4% will ever make it to that level of being able to make it their full time profession. In the Audio Book Industry a experience Narrator can make between $60.00 and $450.00 PER FINISHED HOUR!
So why is this a big deal? When you open Audacity and select your Condenser mic, (this is what most recommend), not only are you opening yourself up to picking up more background noise but now you will also pick up any noise coming through your sound card as well as that is how your mic input signal will be applied to Audacity during your recording. I recommend using dynamic mics for most home studio recordings.
When you add the fact that your noise floor must be a max of -60dbs to meet the ACX requirements, this only complicates the issue. When you open a Professional DAW such as Reaper, this program does recognize the ASIO file that is supplied with most USB Interfaces! This makes it so much easier to meet the ACX requirements.
When I use my little ATR 2100 mic straight into my PC, I have to raise the input level to 100% to peak at Audacity’s Official Recommendations of a -6dbs. When I do my noise floor goes through the roof. All throughout the Official Audacity Forum you will see where they recommend your input level close to or dead on a -6dbs. This advice IS NOT followed by any other Professional DAW Distributors, USB Audio Interface Manufacturer, Recording or Sound Engineer! The best signal to noise ratio you can achieve for digital audio is between a -12 and -18dbs.
This quote was taken from the "Massive Mastering" website. They are extremely well respected throughout Engineering, Mixing and Mastering circles.
Audacity users must be in the -6db range as their program IS NOT a Professional DAW. I understand that they are free and many people use them, but this has nothing to do with recording Professional Audio for the ACX. Not only will this input level likely give you sub-par recording results, but is extremely hard to keep this range for beginners without peaking your audio. Once you go red, (Peak/Clip your Audio) your dead! Your recording is trash! The HIGHER the input level the LOUDER the noise floor. This is mathematics and will NEVER change!So – You have a microphone and a preamp going into a converter or sound card. Those converters are calibrated at LINE LEVEL. In most cases, over the last several years, most I’ve seen are calibrated to -18dBFS = line level (or 0dBVU). In other words, if you run a steady signal (a sustained note on a keyboard for instance) through a preamp and turn up the preamp gain until the VU meter reads 0dBVU, at the converter (and on the active track in whatever program you’re using the record), it will read -18dBFS (or -18dBFS(RMS) — full scale, but measured over time).
THIS IS WHERE YOUR GEAR IS DESIGNED TO RUN. This is where it’s spec’d at. You will have a decent amount of headroom, the lowest distortion, the best signal to noise ratio, etc., etc., etc. around this level or lower. Some gear – usually very high-quality stuff, has a good amount of usable headroom above this level. A lot of “budget friendly” gear does not. So all of this advice is *more* important if you’re using “okay” gear at the input. EVEN YOUR DIGITAL CONVERTERS are ANALOG components up to the converter itself. They don’t want to be “beat up” all the time either.
THIS STATEMENT IS REPEATED THROUGHOUT THE AUDACITY OFFICIAL FORUM!
“You will most likely fail the ACX requirements for Over Processing”.
I will say this the best way I can without coming across as being conceded or condescending. You can follow my advice and excel instantly or spend weeks or months listening to two admins with over 70,000 replies trying to make you jump through EVERY hoop instead of simply telling you the truth by saying “you need to use a professional program”.
Audacity is like the Beta Max machine invented in 1975 when video playback was first invented for home use. Once VCRs came on the scene, Beta Max went the way of the dodos and when movies came out on CD’s, VCR’s met the same fate. Now, how do you listen to your music? 8 Track Players, Cassette Players, CDs or the most recently, Smart Phones. Most would reply CD’s or Smart Phones.
There’s a reason for that, it’s called progress. These two admins are still giving out the same advice they were giving years ago. It did not work back then and it does not come close to working in 2017. The Audio Industry has left Audacity behind as Audacity has failed to keep up with the ever changing Audio Engineering Requirements. It’s just that simple!
1. Question asked by new member. May 3rd, 2017. “Help me with RMS levels and mastering for ACX. Hi, I need some help from the experienced people here on how to improve what I’m doing to get the best sound I can with what I’ve got. I’ve been recording on this setup for many other things, and I generally have my gain set much higher but I recently backed it down because someone said that the reason I’m having to do so much noise cancellation is because I had my gain set way too high. But when I don’t set them high, then my input is so low and I end up raising everything with the Normalization that my room noise goes bananas, so I feel like I’m stuck between a rock and a hard place and I’m not really fixing the problems, I’m just masking them.
Response from Forum Staff Member with Audacity. That’s too low. The fuzzy recommendation is to hit Audacity so the multi-colored display just starts turning colors, first yellow and then orange. The meter will turn angry orange and then red if you get too loud. In numbers, you are shooting for peaks at -6dB.
My comment: When they advise their members to raise their input limit in a “Out of Studio” location, they are failing to tell them this will also raise their noise floor and it WILL NOT pass the ACX requirements. Now they are forced to over process their audio using noise reduction which in turn will also cause them to most likely fail the ACX requirements.
2. Question asked by new member. March 2016. “Recording Levels. Hi everyone, I’m new to Audacity and I’ve been fiddling with the acx plug in that allows you to check if it passes. Without fail, I always seem to be just missing the RMS check. I’m always anywhere from 26-32. Is there any way to just set all the levels I need before I start recording so it just meets all the specifications I need? When I turn up the gain I pass the RMS but fail the noise floor check”.
Response from Forum Staff Member from Audacity. “From above, overload produces permanent distortion, so, much better to go low volume and fix it later”.
My comment. This advice is not only incorrect, it will cause you to FAIL the ACX requirements due to over processing. This advice is in direct conflict with “Record Properly & Master Lightly”. Professional DAWs are used to enhance audio quality while allowing you to fix minor problems. It is not a “magic box” for correcting audio that was not recorded properly.
3. Question asked by member. Reducing Noise Floor. March 2016. “I’m recording narration for video tutorials and elearnings, and I’d like to move into audiobooks/narration. To improve my quality, I need to eliminate the background noise. If I set my mixer to 0 gain and the Audacity recording level to 1.00, then the background noise level (noise floor?) is around -30. I can drop the recording level down to 0.20, which limits the noise to -45 or -40, and still allows my vocals to peak at about -6. With Noise Removal I can get background noise to -48. This is working in my office with a home-made sound booth under a thick blanket. Is there anything else I can do to lower the background noise? Is it better to drop Audacity’s recording level and keep the mixer at 0, or should I cut the level on the mixer too”?
Response from Senior Staff Member with Audacity with over 44,000 posts. “Check the level by speaking loudly into the mic (this is to set up for the maximum input level that will occur during the recording). Ensure that the level on the meters (on the mixer) never go above 0 dB. (It’s OK if the levels are a bit below). Then adjust the recording level on your computer so that the maximum peaks in the Audacity meter go up to about -6 dB”.
My comment: If you have to “raise” your voice to meet the proper input requirements, then you have already lost the battle. As a narrator you will be recording anywhere from 20 to 40 min at a time. Try this for yourself. Just start talking in a loud voice for 2 min and tell me how your throat feels. Not only will you lose your voice but your audio will sound UN-professional as well as UN natural.
The whole purpose of having good equipment is to be able to have your input signal between a -12db and -18dbs WHILE BEING ABLE to keep your noise floor @ -60dbs or lower. This person went the extra mile by using a homemade sound booth as well as covering it with a heavy blanket and they are still close to 50% off the mark!