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Drgiggles1
2009-01-25, 08:42 AM
Basically transferring masters to pc and would like to know if and when to use DB gain and also the bitrate 16, 24, or 32. Not sure about these. Thanks for looking.

GRC
2009-01-25, 09:00 AM
What do you want to do with them at the end of the day?

Share them here, store them on your hard drive and listen to them from there, burn them to CD? Answers here may have some bearing on what settings you use.

Drgiggles1
2009-01-25, 12:30 PM
What do you want to do with them at the end of the day?

Share them here, store them on your hard drive and listen to them from there, burn them to CD? Answers here may have some bearing on what settings you use.
All of the above :)

GRC
2009-01-25, 01:31 PM
CD standard is 16-bit. I would suggest most folks here would be happiest with 16-bit files, but there is the facility for 24-bit, and some folks like that.

You could store them yourself as 24-bit or 32-bit, but you'd need to re-convert back to 24-bit or 16-bit for sharing here, and 16-bit for CD; so depending on your own requirements, it may be more straightforward to stick to 16-bit all the way.

32-bit and 24-bit will eat more space on your drive(s) as well....

What are the masters? Analogue tape? 16-bit DAT? Minidisc? Other format?

Audioarchivist
2009-01-25, 02:49 PM
I'd say if you're capturing anything you'll want to archive and listen to in the future, go with recording at 24 bit. I'm sure as technology progresses further, one day we'll all be looking down at these 16 bit recordings like we look down upon the dreaded eMPty3 file now...

Record and save for later at 24 bit, dither down to 16 if you must for CD use, share at 16 or 24 or both!

DB gain. What for? If levels are very low, then maybe yeah. Keep in mind how awful the loudness wars are and how they ruin all dynamics (loud vs. quiet) on modern CD's. Avoid blindly boosting levels to beyond clipping. Headroom is your friend. Don't kill him with artificially fat signals.

Drgiggles1
2009-01-25, 02:51 PM
CD standard is 16-bit. I would suggest most folks here would be happiest with 16-bit files, but there is the facility for 24-bit, and some folks like that.

You could store them yourself as 24-bit or 32-bit, but you'd need to re-convert back to 24-bit or 16-bit for sharing here, and 16-bit for CD; so depending on your own requirements, it may be more straightforward to stick to 16-bit all the way.

32-bit and 24-bit will eat more space on your drive(s) as well....

What are the masters? Analogue tape? 16-bit DAT? Minidisc? Other format?

Thanks. They are Analogue (maxell xlII;s) for the most part. I heard that 32 bit was the best quality for it which is why I asked. I did my first transfer yesterday at 16 bit with +9 DB gain via audacity. Came out real good imo but I want to get it right also. I'm not to sure about using the gain DB feature so anything you can add regarding that is appreciated. The reason I tried it yesterday was the VU meters reading off the masters were like in the middle of the guage. Thanks again. So for sharing purposes and CD stick with 16 bit. Cool. Than I assume 32 BIT should only be used for highend home equipment. Is this a correct assumption ?

direwolf-pgh
2009-01-25, 03:17 PM
i found this quick read interesting - other than a computer/soundcard, Im not sure whos offering 32bit playback
16 Bit
16 bit matches audio CDs, and is thus suited where the better dynamic range and S/N ratio of CD quality audio is required. 16 bit is a good general purpose high quality setting. 16 bit recording is suitable for vinyl records.

24 Bit
24 bit recording may be used for signals that will be manipulated but still need to maintain the full 16 bit quality of CD audio. 24 bit is good for mastering.

If you're merely listening to thousands of pounds of expertly chosen high end audio kit, and not doing large amounts of editing, there may be no real reason to exceed 24 bit depth.

32 Bit
Some see 32 bit recording as taking things to extremes. Although 32 bit recording can in theory have better technical specs than less bits, it is not often such great bit depth is needed. General purpose recording does not need 32 bit depth for the same reason clothing sizes do not come in increments of 1/1000th of an inch.
Finding audio sources capable of providing signals with better dynamic range than than 24 bit resolution is a demanding task. A 32 bit data stream records 65,000 times the dynamic range of 16 bit CD audio. In real world applications, a lot of those bits will be normally recording nothing but very low level background noise.

Also bear in mind that in many cases you will exporting to a 16 bit format (there are not many computer media players that support playing 32 bit files, and if you are burning to a standard audio CD, that format is by definition 16 bit).

But if you want the highest standards (for example, operate a recording studio), expect to do a large amount of manipulation of the data before export, and have audio source equipment with an extremely low noise floor, 32 bit recording (which is the default setting in Audacity) will give the best possible quality and avoid the bit depth having any effect on the sound even after heavy manipulation of the audio.

Much of the reason for this is that Audacity uses "float" format for 32 bit recording instead of fixed integer format. Normalised floating point values are quicker and easier to process on computers than fixed integer values and allow greater dynamic range to be retained even after editing. This is because intermediate signals during audio processing can have very variable values. If they all get truncated to a fixed integer format, you can't boost them back up to full scale without losing resolution (i.e. without the data becoming less representative of the original than it was before). With floating point, rounding errors during intermediate processing are negligible.

The (theoretically audible) advantage of this is that 32-bit floating point format retains the original noise floor, and does not add noise. For example, with fixed integer data, applying a compressor effect to lower the peaks by 9 dB and separately amplifying back up would cost 9dB (or more than 2 bits) of signal to noise ratio (SNR). If done with floating point data, the SNR of the peaks remains as good as before (except that the quiet passages are 9dB louder and so 9dB noisier due to the noise they had in the first place).

The advantage of using 32 bit float to work with holds even if you have to export to a 16 bit format. Using Dither on the Quality tab of Audacity Preferences will improve the sound quality of the exported file so there are only minimal (probably non-audible) effects of downsampling from 32 bit to 16 bit.

Retrieved from "http://audacityteam.org/wiki/index.php?title=Bit_Depth"

GRC
2009-01-25, 03:21 PM
Remember as well that the sampling rate you use will have a major effect on your results. 44.1kHz is CD-quality, 48kHz, 88.2kHz and 96kHz are also available (depending on your sound card...) - but again, the higher the resolution, the bigger the files, and the larger hard drive you'll need....

Five
2009-01-25, 03:59 PM
just a couple threads down the page you will find this:
http://www.thetradersden.org/forums/showthread.php?t=67415

post in there... or else we should just copy our posts from that thread to this one ;)

zeek
2009-01-25, 04:33 PM
24/96 is pretty much the highest bit/sample rate I would ever seed/circulate and it's good for post production as well. 16/44.1 really should be your final product with no processes run on it if you want to do it right.

I wouldn't take space into consideration really. hard drives are cheap, the tapes you guys make are priceless. Might as well make it so they are workable as technology advances. Not hard to archive raws to DVD. I keep two copies, DVD and hard drive, for every master I work on. If you look around, you can find 1 terrabyte drives for just over $100. HD space shouldn't really be much of a consideration when trading quality for space anymore:)

Audioarchivist
2009-01-26, 03:02 AM
Yeah something else - don't throw away the original tapes after you've transferred them! You never know when some better technology might come your way to do an even better transfer of those recordings at a later date.

Five
2009-01-26, 01:50 PM
Yeah something else - don't throw away the original tapes after you've transferred them! You never know when some better technology might come your way to do an even better transfer of those recordings at a later date.
+1!

dorrcoq
2009-01-26, 03:07 PM
I see no benefit to upsampling a cassette tape to 24 bit this way. You might benefit if you ran your cassette into a 24-bit digital recorder and then worked with that file in Audacity.

If you want to boost your levels, use the "amplify" effect.

zeek
2009-01-26, 03:37 PM
I see no benefit to upsampling a cassette tape to 24 bit this way. You might benefit if you ran your cassette into a 24-bit digital recorder and then worked with that file in Audacity.

If you want to boost your levels, use the "amplify" effect.

If you have a 24/96 capable soundcard, your writing to 24/96, not upsampling. Doesn't matter if you go through a recorder or your soundcard, same difference if you have the right software/hardware. I didn't like audacity much so i never really dug into the nuts and bolts of it so maybe I'm missing your point but I'm pretty sure he's capturing his transfers with it, correct?

GRC
2009-01-26, 05:14 PM
+1 - you're only upsampling if the source has been sampled already. Copying an analogue source to 24/96 is sampling it for the first time.