Freesound Forums

THis is a cool sight and i am new to this audio world. I made a full feature film and am using some of these sounds in my movie. However, some of the files are aif.
does this matter? all my other audio files are WAV and some of these good sounds are aif.

I worry about using the aif files because i am not sure how it will sound mixed with the WAV's when i render it for the finished product. or does it not matter?

Also All of my own personal WAV files say
the bit rate is 4680 under the properties function on my computer

some of the sounds I downloaded do not say 4680. i don't know how to find the sample rate but will this be any problem in the future upon making the final copy? do all of my sounds for my movie project have to have a bitrate of 4608?

If your video making software can handle AIFF files, it won't make a difference mixing them to WAV files, everything will be downmixed to a whole stereo track.

FLAC, WAV and AIFF give you the original sound quality, without the loss you'd get with MP3, OGG, WMA, etc.

I have no idea where that 4680 comes from, and anyway "bit rate" is something you'd find regarding compressed formats like MP3 or OGG; what counts in your case are the *sample rate* and the *bit depth*; the CD standard uses respectively 44100Hz and 16 bit. That means that 16 bits are enough, more are better. Since you need to add sounds to a video, a more proper sample rate is 48000Hz (or multiples, 96 and 192kHz) as that's the default in video making software.

If you look at the page of a single sound (e.g. this: http://www.freesound.org/people/copyc4t/sounds/248257/ ) you find all the relevant info on the right.

hi thanks. yes my sample rate is 96. (not sure about the bit depth) so does that mean i can only use sound affects with the exact same sample rate? or are the ones i have acceptable even though they are not 96?

Better yet here is what my recorder says

Rec Format -PCM-24
Sample Rate 96K

Dual mono mode

I know what dual mono is but i had a guy at the store at the time do the presets for good audio and i've been so busy i never wraped my head around it so I am just trying to clear things up

96K is great news; first, because it's a multiple of 48K so it's well suited for video, second because it's even better defined. Your recordings should work flawlessly with your video making software.

Also, video making programs usually take care of resampling anything internally, so that you can mix sounds at different sample rates, but that works better with exact multiples; anyway, throwing in short 44.1kHz sounds is still possible of course.

The 24 in the PCM-24 format specification is the bit depth, and that's great news too; 44.1/16 as said is the CD standard so it's good enough for a final audio product, but it's good practice to work as high as the gear allows and only convert down at the end after all the eventual processing.

thanks man. so on this web site what numbers should I be looking for when it says bit sample rate and bit depth? and stuff like that?

You're welcome.

Sample rate, preferably 48000.0 96000.0 192000.0 and 384000.0; as said 44100.0 will work reasonably well too; lower sample rates would lack high frequency content in the audible range, so avoid them unless a lo-fi feeling is exactly what you're after for specific sounds.

Bit depth, 16 or above; same lo-fi consideration for anything below, which introduces audible distortion.

I'd just like to add that even though you may record at 48K+, it is held by many in the audio world that anything more than that is overkill. It just increases file size (and requires more processing power) and the average/above average ear hardly ever hears the distinction between a sample recorded at 44.1K and 48K, much less 48K and 96K (althugh many people will claim to be able to hear the difference -- keep in mind, we only hear 'til 22K, and about 18K for most aging people).
Like copycat said, CD quality is 44.1K and 16 bits, whereas DVD is usually 48K and 24.
If you don't mind the file size, I think 96 is fine, but still an overkill (note however, though, that if you're converting it down to a smaller sample rate, a 96KHz will convert better to 44.1 than a 48 would. Also, according to a post in the links below, time-stretching is not too distorted when you work with 96).

https://www.sweetwater.com/forums/showthread.php?27340-24-bit-48kHz-verses-24-bit-96kHz
https://www.gearslutz.com/board/high-end/165264-96khz-better-than-48khz-multitrack-digital-recording.html
https://www.gearslutz.com/board/newbie-audio-engineering-production-question-zone/861682-24-bit-96khz-vs-24-bit-192khz.html

Thanks for all the above info. I was just searching on this topic.