Best Achievable Acoustics for Voiceover Recording Space

[VoxNova]

Hi Everyone!

My name is David, and I’ve come seeking input and advice on how to achieve the best acoustic qualities for a space / environment to be used for voice / voiceover recording. I will firstly and freely admit that after having done a great deal of reading, and talking to various people (some more experienced than others) about how to achieve my objective, I am confused. With that said however, I am dedicated to getting it right, and I take the wisdom of Gregwor’s signature line “It appears that you've made the mistake most people do. You started building without consulting this forum" sincerely to heart. Both my approach, and my room, are blank slates.

As a preface to the details below... I would like to offer that I have been overwhelmingly impressed with the generosity or time, content, objectivity, expertise and selfless spirit demonstrated on these forums. It is unlike anything I have ever seen. And even if it's just in this small corner of the Interwebs... there might just be hope for us all yet.

I have done a number of searches with "Search for all terms" enabled. While I certainly might have missed something, after reading numerous and varied threads, I ended up with less than the less than confident sense I had when I started, about how to proceed.

I reviewed the "FAQ" and most of it was way above my pay grade, and the information and projects listed were much larger in scope than I think I can manage, or perhaps, actually require (but I don't know). I will say that John Shryock's vocal booth thread gave me considerable wood envy (yes, yes I know)

"In Scope" Objective:

Provision the best achievable acoustic qualities in a voice / voiceover recording environment (given physical space and budgetary constraints - please see below)
- best achievable acoustic qualities for voice recording
- consistency / repeatability in the acoustic environment

"Out of Scope" Considerations:

Vocals (singing)
Tracking (instruments)
Mixing / Mastering

How Loud Am I?:

Fashion choices aside - projected speech levels.

Budget:

$1,250.00 CAD (with some modest upward flexibility)

DIY Skill, Tooling and Willingness Levels:

Skill Level: Moderate
Tooling Level: Moderate
Willingness Level: High

Number of Unmentioned / Forgotten Poles in Diagram:

None

Recommendations / Suggestions Considered or Received to Date (with my novice "acoustic confidence" level +/- 1->10):

Please keep in mind that I have no preconceived preference on how to proceed. I am results, not approach oriented. My "acoustic confidence" in these suggestions may be unreasonably high or low. I really have no idea, having no personal experience with any of them. Maybe the answer is in this list, maybe it's not.

You want the "deadest" space you can get for voice recording (+/-?, I don't know)
You DON'T WANT the "deadest" space you can get for voice recording (+/-?, I don't know)
Buy a "Mud Guard" or similar (-10, consensus is "useless" and I agree, cardioid polar pattern etc. etc.)
Hang a blanket over your head / mic (+1, not practical, there have got to be better ways)
Bedroom closet (+5, but in my place they're all 6.5' L x 28" D w/ plastic accordion sliding doors)
PVC pipe frame and moving blanket type "fort" (+3, but I have some budget, and some space to work with, can I do better?)
Buy a "Vocal Booth To Go" (Producer's Choice) Portable Vocal Booth (+5, with US/CAD exchange rate plus shipping, duties etc. it's out of budget, and better results might be possible "locally")
Buy a "Whisper Room" (+6, very expensive, and sems many people need lots of DIY treatment inside anyway to avoid "boxy" sound)
Build a "Real" "Vocal Booth" (+6, I don't believe I have enough space, budget and certainly not enough permission to do this properly)
Build a "GOBO" "Vocal Booth" - freestanding GOBO's arranged as a "room" (+5, interesting idea, but no sense if it's a good or bad idea)
Hang "Auralex" all over the walls (+2, it's expensive, and from what I've read, won't do enough of what I want / need it to do)
Properly treat the entire room i.e. absorption, bass traps, clouds etc. (+7, strikes me as the most flexible, appropriate solution. Maybe it's not. If it is, I don't really know how to proceed)

Current Equipment includes:

Rode NT-1 LDC Microphone
Focusrite Scarlett 2i2 Interface
PreSonus Eris E4.5 Monitors
Sennheiser HD280 Pro Headphones

Room Specifications (dimensions / features):

VORoom.png

As indicated in the attached image (which I hope provides at least a suitable level of detail to begin with) the room I intend to use is on the second floor of a rented townhouse. I understand and appreciate the difference between "isolation" and "treatment / absorption." Given that I don't own the space, my initial sense is that I will have to forego the former and do what I can with the latter. I'm not at all opposed to "building" isolation WITHIN the space if that's what's ultimately recommended. Building anything "ON TO" the space however, and or modifying the existing physical structures of the room will unfortunately not be possible. I will make amends with my fate and suffer the expected acoustic intrusions and injustices that come with living in adjoined spaces, and adjust my schedule as might be required to record while the rest of the world is (hopefully) silentish. But when that time arrives, I need the recording / acoustic quality to be the best I can make it.

My Questions:

1. For voiceover / voice recording, does one want a completely "dead" space to record in?

2. Are my "acoustic confidence" levels in the items on the "Recommendations / Suggestions" list above "sane" i.e. am I evaluating these things in / at a reasonable way / level?

3. Regarding #2 above, is the best solution already on that list? If so, which item(s) please?

4. As mentioned, my (perhaps misguided) sense is that from that list, "Properly treat the entire room i.e. absorption, bass traps, clouds etc." is likely to be the best way to go. Am I correct about that?

5. Regarding #4 above, if I am correct about treating the entire room, would the collected wealth of experience and knowledge here be willing to help me understand how best to do that?

I will swing the hammers and run the saws, or buy or borrow the gear needed to run REW or hang the blankets or whatever else might be necessary. In short, I will be your hands and eyes, if you will please lend me your ears and brains.

Thank you all very much in advance for your consideration, and for any input you would care to provide. Thank you!

Regards,

David

[Soundman2020]

Hi David, and welcome to the madhouse... err, I mean Forum!

You started off with possibly one of the most complicated questions to answer, so I really hope your followup questions get simpler and simpler, rather than going the other way!

OK, simple short answer: there is no simple short answer! Well, let me moderate that a bit: Vocal booths need to sound neutral, of course, without adding coloration to the sound of the narrator's voice, and with taking too much away from it, so that would be the first, most basic guideline: neutral acoustic, which is normally taken to mean "flat frequency response". ( More on that later, because there is no such thing... ) But beyond that "it gets complicated".

So first off, the general aim is "neutral, natural acoustic frequency response".

Next, decay times: there are guidelines for how long the sound should continue bouncing around a room after the source stops, for different scenarios. In other words, if you yell "HELP" real loud, for how many more seconds can you hear the various sounds that make up that word, before they all die away to nothing? That's decay time, and it varies by frequency. So you want the decay times "flat" too, in the sense that if you say the word "SOUP" in the room, then the high frequency sibilant sounds of the "S" die away at about the same rate as the low frequency plosive sound of the "P", and those both die away at the same rate (roughly) as the long vowel sounds of the "OU" in the middle.There are some suggestions and guidelines for decay times for various types of room. More on that later, because once again "your mileage may vary".... To be more specific, you probably want an overall decay time in the region of around 300ms to maybe 800ms, but that depends greatly on room size. If the room is very small, then it would be much shorter.

So those would be the two big concepts you should be aiming for : reasonably flat frequency response, and reasonably flat decay times.

Now for the kicker: you can't actually achieve that in a live room! In a control room, it is relatively easy to achieve it, because the sound sources are fixed at a specific location in the room (the speakers are bolted into the walls), and the sound receiver location (the ears of the engineer) are also fairly well constrained to one location: the place at the console where his head is while mixing. So it's "simple" (relatively) to create the acoustic treatment around that layout, such that you really do get relatively flat frequency response, and relatively flat time-domain response. But in a live room (tracking room), that isn't the case, because the sound source(s) can be anywhere in the room, and so can the sound receiver. In other words, the talent can stand anywhere in the room, or sit, or kneel, or lie down, or stand on a table, or chair... and the mic can be anywhere in the room, from wall to wall and floor to ceiling. It is impossible to have a room that is entirely neutral for all of those combinations. The only room that can get close to achieving that is an anechoic chamber, but you wouldn't want to record in there. It is deader then the grave. Not nice. You'd also need a few million dollars to build one...

So, what you can do is to lay out the room in such a way that the vocalist will always be somewhere in one general region, and the mic always in another general region. That makes your job a bit easier. Not much, but some....

The general rule for vocal booths is that the mic needs to "see" a mostly absorbent surface, and the talent needs to see a somewhat reflective/diffusive/absorptive surface. In other words, the vocalist faces a wall that is mostly hard, but has some absorption on it, and possibly some diffusion. The choice depends on the size of the room, and other factors. Then behind the vocalist, the wall is pretty much mostly absorptive, deeply so, with perhaps some reflection and/or diffusion up high and down low, where the mic doesn't "see" it so much.

Real example: the vocalist faces a window into the control room or live room, with the mic between him and the window. The window is surrounded on the sides by slat walls, with deep absorption below and above, and perhaps some light diffusion. The wall directly behind the vocalist is a panel of thick broadband absorption, then out to either side of that are some small poly-cylindrical diffusers.

Now, this is VERY general, of course! So please don't go running around the internet saying you finally found the one-and-only solution for vocal booths! That's just the general concept, overall guideline.

Apart from that, you will likely need some bass trapping in several corners: even though it's a vocal booth, there will still be modal stuff going on that you want to kill, so you don't get that deep "boomy" sound typical of poorly treated rooms. The floor is usually left hard and reflective, perhaps with a small throw-rug, and the ceiling mostly "soft" (absorptive) with some reflective panels, to keep a little life in the room.

Once again, those are just GENERAL concepts! Nothing written in stone!

This is probably the reason you came up confused after your research: So many opinions! Because rooms vary widely in dimensions, and people vary widely in what THEY consider "good sounding". For control rooms, there are strict specifications that need to be met, but for vocal booths, there's nothing like that. Only general concepts and guidelines. In fact, I'm sure some people have told ou something like: "It's a live room: make it any way you want that sounds good to you!". Not very helpful, and no it is not a live room: it is a vocal booth, which is different, and it is possible to set some limits on the acoustics for that. As above.

Properly treat the entire room i.e. absorption, bass traps, clouds etc. (+7, strikes me as the most flexible, appropriate solution. ...)

Yup. That's about it!

Your room is decently sized: at roughly 14' x 9', you +/- 130 square feet, with an 8 foot ceiling, so maybe 1000 cubic feet or so. It's not large, but it certainly isn't a closet, so there's a good chance you'll be able to get it sounding very good for vocals. If you also want to do various instruments in there, then I'd suggest adding some variable acoustics panels, so you can adjust the acoustic response as needed for each situation.

1. For voiceover / voice recording, does one want a completely "dead" space to record in?

Definitely not! It needs to sound neutral, natural, not live, but also not dead. Towards the dead side, maybe, but not totally dead. That sounds lousy, and is unpleasant to work in.

4. As mentioned, my (perhaps misguided) sense is that from that list, "Properly treat the entire room i.e. absorption, bass traps, clouds etc." is likely to be the best way to go. Am I correct about that?

Yes, but with caveats. Is this going to be a professional VO booth? For example, for ADR type work? Or maybe radio jingles? Commercials? News / discussion? Creating audio books? Eg, needing high quality recordings? Or is this more of a personal hobby style room? If you plan to charge money for the use of the room for movie ADR work, or for high-end work that you do in there yourself, then it should be treated the best it can be. If this is for hobby use, then that probably isn't necessary. Or if the usage is "somehwere in between" those two extremes, then modify accordingly.

5. Regarding #4 above, if I am correct about treating the entire room, would the collected wealth of experience and knowledge here be willing to help me understand how best to do that?

I think we already made a start on that...

All of the above assumes that you do not need to isolate your room: you already mentioned that as a possibility in your post, so the very first thing you should do is determine if you need that, or not. Time to get out your hand-held sound level meter, and do some measuring. Set it to "C" weighting and "Slow" response, then take readings inside the room at various times of day, when various things are happening in and around the house, as well as outside in the street, and overhead: such as wind, rain, thunder, hail, aircraft, helicopters, street traffic, sirens, neighbors lawnmower, dogs barking, vacuum cleaner, doors opening/closing, people walking around in other rooms, radio, TV, cell phones, etc. Along with looking at the numbers on your meter, also just listen! If you can hear some/many/all of those above at the typical times of day when you'd be recording vocals, then you need isolation. If you cannot hear any of those, not even a little bit, and the meter says "ERROR" because the ambient level is so low it can't read it, then you are fine!

One you have done that, set up your Rode, interface, and DAW in the room, and record the ambient sound. Then play it back on headphones. Mics and ears do not work the same way, so it is quite possible that the mic will pick up sounds that you didn't notice with your ears. If you can hear background sounds on those recordings, then you probably need isolation. Of the recordings are dead silent, then you are OK.

So first of all, define if you need isolation or not. Then based on that, we can go to Step 2. Hopefully you do not need isolation, because your budget is not going to allow it....

or buy or borrow the gear needed to run REW

You have speakers, a mic, and a DAW (I'm assuming) so you have enough to run REW already. But it probably isn't necessary at this stage. First, define isolation. Then we can worry about analyzing your room, and treating it. You won't be running REW the same way you would for a control room, and you don't need that type of precision, so your Rode mic and E4 speakers are likely good enough to do what needs to be done, if it needs to be done.

- Stuart -

[VoxNova]

Hi Stuart... it's a pleasure to make your e-acquaintance! Thank you very much for your welcome, and your detailed response!

You started off with possibly one of the most complicated questions to answer, so I really hope your followup questions get simpler and simpler, rather than going the other way!

I'm generally only capable or producing one, at best two good questions per conversation... please rest assured, the remainder have no hope of competing.

"SOUP"

Had I known there was going to be soup, I would have saved some room from dinner.

So those would be the two big concepts you should be aiming for : reasonably flat frequency response, and reasonably flat decay times.

Understood.

Now for the kicker: you can't actually achieve that in a live room!

I hadn't considered your point about the potential for variability (and relativity) in the position(s) of, and between, the sound source (me) and the receiver (the mic).

So, what you can do is to lay out the room in such a way that the vocalist will always be somewhere in one general region, and the mic always in another general region. That makes your job a bit easier. Not much, but some....

A bit (easier) is better than none at all. I have dominion over the space in question so "formalizing" the mic and source positions is certainly doable.

Now, this is VERY general, of course! So please don't go running around the internet saying you finally found the one-and-only solution for vocal booths!

For a brief, all too fleeting moment I saw fame, fortune, my name up in lights... and then, just as quickly, nothing.

Apart from that, you will likely need some bass trapping in several corners: even though it's a vocal booth, there will still be modal stuff going on that you want to kill, so you don't get that deep "boomy" sound typical of poorly treated rooms. The floor is usually left hard and reflective, perhaps with a small throw-rug, and the ceiling mostly "soft" (absorptive) with some reflective panels, to keep a little life in the room.

I'm certainly up for building traps, absorbers, treating the ceiling etc. as (if) a requirement for those things presents itself. As mentioned, the floor is carpeted and will have to stay that way but I can and will do whatever else might prove to be necessary with regard to treating the rest of the surfaces in the room.

Once again, those are just GENERAL concepts! Nothing written in stone!

Fully understood.

[...snip...] it is a vocal booth, which is different, and it is possible to set some limits on the acoustics for that. As above.

Given that there are no codified standards for vocal booths, it only seems logical in my admittedly novice opinion that there are at very least some "standard" things one would want to achieve. As you've said... "As above."

[...snip...] so there's a good chance you'll be able to get it sounding very good for vocals.

This pleases me!

If you also want to do various instruments in there, then I'd suggest adding some variable acoustics panels, so you can adjust the acoustic response as needed for each situation.

As mentioned in the "Out of Scope" items there won't be any need to track instruments etc. The room will be mission specific, if you will. Voiceover / narration is all that will be recorded in it.

[...snip...] Is this going to be a professional VO booth?

While I'm new to it, I fully intend to get paid for doing VO, so yes, high quality recordings. The room won't be hired out, but I most certainly want to treat it as best it can be / as best I can. No ADR work, unless I get cast in something (seems quite likely ) that needs to be looped. Longform narration / audio book production will be my primary focus, but other types of commercial VO (and perhaps some VA) type work will be sought as well.

5. Regarding #4 above, if I am correct about treating the entire room, would the collected wealth of experience and knowledge here be willing to help me understand how best to do that?

I think we already made a start on that...

No question about it! And with all else set aside, it is sincerely appreciated. Thank you Stuart.

All of the above assumes that you do not need to isolate your room: you already mentioned that as a possibility in your post, so the very first thing you should do is determine if you need that, or not.

The first things are always best done, first.

Time to get out your hand-held sound level meter, and do some measuring. Set it to "C" weighting and "Slow" response, then take readings inside the room at various times of day [...snip...]

I'm on it. Save for not actually having an SPL meter. That being said, I am never more than even the weakest of excuses away from being convinced to buy new gear... and this, well, this is in fact a legitimate pursuit. In some of your other posts I've seen you give a favourable recommendation to the Galaxy CM-130. They're available and in stock locally so I'll have one in hand tomorrow.

[...snip...] when various things are happening in and around the house [...snip...] lawnmower...

I envy you your Chilean climate Sir... but alas up here, we're months away from lawnmowers. Now, snowblowers... those, those we have!!!

One you have done that, set up your Rode, interface, and DAW in the room, and record the ambient sound. Then play it back on headphones. Mics and ears do not work the same way, so it is quite possible that the mic will pick up sounds that you didn't notice with your ears. If you can hear background sounds on those recordings, then you probably need isolation. Of the recordings are dead silent, then you are OK.

So shall it be written, so shall it be done. I've gotta say though, I've lived here for quite some time and I'm concerned about getting away "dead silent."

So first of all, define if you need isolation or not. Then based on that, we can go to Step 2. Hopefully you do not need isolation, because your budget is not going to allow it....

Here again, fully understood. As mentioned, I'm resigned to having to work while most others are hopefully (and quietly) sleeping. As you've recommended I'll make and record SPL measurements at various times of day / night for sake of comparison.

And while my budget is by no means infinite, as we go it would be useful for me to develop an "ok, good, better, best" sense of the costs involved at the higher levels of that continuum. What monies I have today, will be augmented by those I receive tomorrow.

You have speakers, a mic, and a DAW (I'm assuming)

Audacity, for the moment anyway (but open to and actively looking at alternatives).

First, define isolation. Then we can worry about analyzing your room, and treating it. You won't be running REW the same way you would for a control room, and you don't need that type of precision, so your Rode mic and E4 speakers are likely good enough to do what needs to be done, if it needs to be done.

Excellent!

Thank you again Stuart. I'm feeling motivated by having an approach to follow, so, thank you for that as well.

Please, stand by...

Chao!

David

[VoxNova]

Well... the ballots are in, and the votes have been counted.

I "tested" the room at various times of day (and night) for 5 minute intervals and while the transient peak readings were quite a bit different during the day than at night, the average dBC SPL is ~42.

The CM-130 doesn't do any data logging so I paired it up with an app on my phone that does. I know the consensus is that SPL meter apps aren't of much use, but after calibrating the app using the CM-130 the results were quite impressive. I've included a pic of the app running next to the CM-130 in the room just for demonstration's sake.

While I wouldn't call the results at all scientific, from an anecdotal perspective, supported by some data, it's fair to say that the room is generally pretty quiet, but... I can definitely hear various, random audible incursions and intrusions. I frankly didn't expect not to, but it's surprising how much "noise" there is when you're listening for it, and how well our ears / brains filter it out when you're not.

As I've said, I'm an eager to learn novice at this stuff but even at that, some of what I've found, confounds me. The MAX dBC from the CM-130 in the wee hours of the morning is ~50, and that's rare. The overall average is consistently in the ~42 dBC range regardless of the time of day. More often than not, when the meter MAX's I can't "hear" what created the reading. However, both my mic and I can "hear" incidental noise from outside, and from the adjoining townhouses that doesn't seem to register on the CM-130. Does that make sense, despite being counterintuitive, or am I perhaps missing something, or doing something wrong?

Following is a plot from the app of the most recent test interval at about 11:20 AM this morning. I overlaid an Excel chart compiled from the summary data that the app outputs (which is otherwise in text format). I'm not sure why the app doesn't plot the "peak" reading, but it does include that reading in the summary output, so it's included on the Excel chart.

The "Min," "Max" and "Leq" are time weighted over the test interval (in this case 5 minutes) and the "Peak" is a raw data point without any weighting. The app's recorded "Peak" during this test interval was ~1.5 dBC higher than the "MAX" value shown on the CM-130 for the duration of the test.

031419-1120AM.png

And just for the sake of sake's... a pic of the CM-130 and the app running side by side to show that once calibrated to the CM-130, the app is surprisingly close.

HPIM0780.JPG

With all of that said... I think it's pretty clear that some effort is going to need to be made to "isolate" at least some portion of the room, or, as previously indicated, record while the rest of the world is asleep, and do what I can to mitigate any audible intrusions (i.e. take a break, or rerecord any takes that include extraneous noise(s).

Stuart - I know you've indicated that for the budget I outlined in my OP, isolation wasn't going to happen. Taking that to heart, but putting it aside for just a moment, what approach would you suggest to achieving some measure of isolation in at least some portion of the room?

Additionally, if it comes down to the "while the rest of the world is sleeping" approach... are there any steps I can be taking in the interim to determine / quantify how the room needs to be acoustically treated?

Thanks!!!

David

[Gregwor]

David,

It's great to see someone from around here on the forum. I'm just North of you in St. Albert! If you ever need a set of eyes on something, don't hesitate to reach out man!

And just for the sake of sake's... a pic of the CM-130 and the app running side by side to show that once calibrated to the CM-130, the app is surprisingly close.

Very cool! What app is that?

what approach would you suggest to achieving some measure of isolation in at least some portion of the room?

Achieving isolation is a big expensive job, no matter what. The larger the room, the more time and money it takes. I have friends who have gone the basic routes of clips + hat and two layers of 5/8" fire core drywall with green glue and it has helped enough for their purposes. That might be enough for what you need.

Do you own the place? If you do, why can't you rip out the carpet? Carpet literally creates the exact opposite acoustic response you need in your room. Also, if you own the place, can you get handy and cover up your window with heavy materials such as OSB + drywall?

With your budget, I'd cover up the window, rip off the existing drywall (that includes the ceiling drywall), fill the walls with Owens Corning R24 (you can buy 16" O.C. at Home Depot where we live). Buy isolation clips and hat channel, then put two layers of drywall (CGC 5/8 inch SHEETROCK Firecode Core (Type X) Drywall Gypsum Panel from Home Depot --> be sure to get them to price match Consolidated Gypsum) up with green glue compound between them. Go to Windsor Plywood and buy a Masonite brand primed (or finished) hardboard door slab. Buy an automatic door bottom from them or Nelson Lumber. Install the door with some great seals around the entire thing. If you can put a seal across the floor, do that too. Don't cut a hole for a door handle. Use a door handle like you'd find on a commercial door. Install an automatic door closer that you can buy at Amre Supply to hold your door tight against your seal.

The only other thing is HVAC. This is very important. If you designate a chunk of your room for HVAC silencers, that would be great. You could probably get away using one for supply and one for return. That wouldn't eat up too much space.

These supplies would probably eat up all of your budget. So maybe while you do this, you can save up more money for acoustic treatment devices. This won't give you super good isolation (the amount you'd need for loud instruments), but it would really improve your current situation and be affordable.

are there any steps I can be taking in the interim to determine / quantify how the room needs to be acoustically treated?

Like Stuart said, you will need as much bass trapping as you can fit. There are calculators online to help you roughly determine what materials you would need in your room to achieve your desired decay times.

Again, thanks for joining the forum. With your current attitude, I'm sure you'll have a great usable space!

Greg

[Pleezel]

I have been doing audiobook post production for almost 20 years now. The last decade has seen a big shift from almost universal commercial studio recordings to remote, home studios. (hooray for a burgeoning industry!) That said, the commercially available portable sound booths that many of us (including me!) have to suffer with are horrid sounding things but do allow for passable product accounting for the vast majority of commercial audiobook recordings on the market right now. Heavy use of EQ and noise reduction software are, unfortunately, standard these days.

As a producer and post engineer, "dead" is what we're looking for. On top of that, a low noise floor "-60dB RMS" is Audible's standard. So, if you can meet those requirements, you'll be golden.

Kudos to you for taking steps to make a decent sounding room. I can't wait to do the same and will be watching this thread with interest.

[Soundman2020]

the commercially available portable sound booths that many of us (including me!) have to suffer with are horrid sounding things

Right! Especially considering that they don't even work very well, and likely make your recording sound worse, rather than better: https://www.soundonsound.com/reviews/ho ... cal-booths . That's a great article, and so true.

As a producer and post engineer, "dead" is what we're looking for.

For the typical tiny closet-sized "rooms" used for podcasts, there's not really much choice: It's either "dead" or "really ugly dull boxy sound". Given that choice, dead is better. But for proper vocal booths in good recording studios, "dead" is not the best. "Neutral and natural" is what most people look for. Decay times around 100ms-200ms or so can make a vocal booth sound quite good, as long as it is balanced, and with the mic and talent set up correctly (no reflective surfaces behind the talent, for example). The problem with "dead" is that it is fatiguing for the talent, since it is unnatural. One of the reasons why the original LEDE design concept died, and was replaced by things like RFZ, and NER.

a low noise floor "-60dB RMS" is Audible's standard.

This is rather confusing... Is there a typo there? I've never heard of measuring sound pressure levels in a room using units of "dB RMS" before, and I'm not aware of any instrument that could even do that. And "-60dB" relative to what? RMS is for electrical signals, such as voltage, current, or power, not SPL, because SPL is already RMS, by definition... Maybe you typed that wrong?

Noise floors are usually measured using the NC or NR ratings, because the frequency spectrum of the noise and the equal-loudness curves are a key parts of it. Studios pretty much always specify noise floor using NC or NR.

- Stuart -

[Pleezel]

"Neutral and natural" is what most people look for. Decay times around 100ms-200ms or so can make a vocal booth sound quite good, as long as it is balanced, and with the mic and talent set up correctly (no reflective surfaces behind the talent, for example).

You know how many times I read that as “delay times"? Agreed, but for most home studios, especially to those of us in high cost of living areas which necessitate the need to move often and thus the use of portable and/or makeshift booths (ughhhh) that’s a sad, on the ground reality.

The problem with "dead" is that it is fatiguing for the talent, since it is unnatural.

Many US narrators wish our tax code allowed us to write off the therapy that being stuck in an unnatural, dead padded room for 8-10 hours a day requires for some semblance of mental health. I really wish I was kidding.

a low noise floor "-60dB RMS" is Audible's standard.

This is rather confusing... Is there a typo there? I've never heard of measuring sound pressure levels in a room using units of "dB RMS" before, and I'm not aware of any instrument that could even do that. And "-60dB" relative to what? RMS is for electrical signals, such as voltage, current, or power, not SPL, because SPL is already RMS, by definition... Maybe you typed that wrong?

Here’s a screenshot of Audible’s submission guidelines:

608F9146-5953-4A8D-8599-2057613B7A9D.jpeg

Lol, that’s why it was in quotes, but the reasoning for that wording in the submission guidelines I suspect is standard practice is sending 30 seconds of dead air, which then gets run through DAW metering (eg. Pro Tool’s Gain), metered in RMS as opposed to peak.

When the single largest employer (arguably) of voice actors in the world makes such a request, not many - including me - are going to “well, actually” them.