I know not to switch the sample rate after a session has been established. However, is it kosher to record one song at 24bit 96K and another song to be released on the same album at 24bit 192K? If I have a song with lots of instrument tracks to record I usually work at 96k whereas if the song needs to be just guitar, vocals, and a few overdubs I go with a higher resolution. I plan on bouncing the mix at the original bit depth and sample rate to give to a mastering engineer. In the mastering process the 1s and 0s should go through some great converters before it hits analog gear. Will this cause any digital disasters as the mastering engineer then brings everything down to CD quality at 16bit 44.1K? What sample rate does Alan find himself using the most?
Thanks,
CW
Singer Songwriter
www.colterwilson.com
Most DAW software will convert your samples to a 32-bit floating point representation internally in order to apply the various mathematical manipulations required by all the processing. Then when you are ready to render you will render the output of all the mathematical processors to your nominated bit depth, which will probably be 24 bit to send off to mastering.
The sample rate, as you have pointed out, should be fixed for each track or project, so all the AD and DA converters are set to the correct clocks. However to use different sample rates for different tracks on a project is a little unusual, but should not be a problem. Just make sure you document this for the mastering house. There should not be any problems when it is converted down to 44.1k for replication if the mastering engineer is using high quality rate conversion algorithms.
I get a fair share of works to master from Nashville and almost all of them come to me in 24/48K. The only time I heard any difference at all between 192K and 96K was a recording of live fireworks bussed to two recorders, recording each (96K and 192K)
The crest factor was slightly higher on the 192K and appeared to have a shade more "nose bleed" to the impacts. I seriously doubt the 192K/96K differences on music can be heard by many people every time.
Some say they can hear it. Some DAWS may or may not handle the 192K in summing to an audible difference. Use what gives you the most vibe. This is what it is all about anyway. Does the music reach your soul?
I never down-sample a transfer prior to mastering. If the tracks come in here at 192K, they stay that way when in digital but as most mastering goes, a lap or 2 through analogue is the norm before recording back to the DAW.
Studio Engineering Since 1975
I've been interested in this topic and done some research and as well gathered some information.
first - if your final form is CD - go for 44.1 or 88.2, if you know that there will be a video - 48 or 96
more important is that you keep at least 24bits and if possible 32 bit float - the last one of course preferable.
a good material is in DVD by Friedemann Tischmeyer (Stainberg WaveLab Audio Mastering tutorial) where he explains the science, mathematics and what is just a placebo effect in audio. It changed my perspective, I'm not some well recognized mastering engineer, or a big studio owner, but I know that technical detail can jeopardize the creative part and when you are to much concerned about sample rates and bit depths you loose your attention of getting the best take, mic position, mood or what ever you need to capture and convey to listeners.