Topic: Sample Rate 44.1 vs. 48

[boojum]

My completely worthless opinion:
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99% of all CD/DVD players these days resample it to 24/96 or higher any way.  Might as well just stick with Redbook and let the hardware manipulate it (w/o it costing you time and money to try and achieve something you cant achieve in the first place).
<snip>

If you have 16/44.1 no matter how highly it is upsampled and how much greater depth it will make no difference.  When you Xerox a digital image at a higher pixel depth it gets no sharper.  What was blurry in the original will be blurry in the copy.   The copying can't make it any sharper.  Likewise in audio.

[Nick's Picks]

but what if your almost out of ink?  then what

[Ozpeter]

The headroom argument is good, so long as you bear in mind that it's only digital headroom - you still have to worry about not clipping the analog stages. 

Certainly in post-production, loads of bits in your DAW means that you can forget about per-track headroom, and only worry about the master.  But that applies equally with a 16 bit original file or a 24 bit original file - it's the internal processing of the mix engine that comes into play to give you that big headroom.

[boojum]

The headroom argument is good, so long as you bear in mind that it's only digital headroom - you still have to worry about not clipping the analog stages. 

<snip>

I have only one analog stage: playback.  I control that clipping with the volume control.  And it is very rarely a problem.

[Ozpeter]

I have only one analog stage: playback

Really?  How's that done?  If you are deciding to make a 24 bit recording, then somewhere along the line you must be using an analog to digital converter set to convert analog audio to digital data represented with 24 bits.  And that's got an analog stage (its analog input).  A fully digital microphone (somehow converting sound waves direct to digital bits with no moving parts) has yet to be invented - and probably never will be.

[boojum]

^^^^ Well, you got me there.  OK, the mics, both sets, are good to 125+ dB so I think I do not need to worry about that, don't you??? 

[Nick's Picks]

I have only one analog stage: playback

Really?  How's that done?  If you are deciding to make a 24 bit recording, then somewhere along the line you must be using an analog to digital converter set to convert analog audio to digital data represented with 24 bits.  And that's got an analog stage (its analog input).  A fully digital microphone (somehow converting sound waves direct to digital bits with no moving parts) has yet to be invented - and probably never will be.

neumann solution D
any of the "USB" microphones ?

the neumanns have AES output directly from the microphone.  sure ,there is an analog stage in there..but not much of one.  ADC built right into the preamp body.

[Tim]

If you have 16/44.1 no matter how highly it is upsampled and how much greater depth it will make no difference. 

I assume you have done extensive blind testing to reach this conclusion.

From my own experience I couldn't disagree more. Run analog out of a Tascam DA20mkII into your stereo, next run digital out of that same deck into a nice upsampling DAC. You are contending that there is no difference in the sound?

[DSatz]

Just the basic simple answer to the question: It is possible, with some program material and some equipment, that a 48 kHz recording could sound better than a 44.1 kHz recording. It is also possible for the reverse to be true. This is because every recorder or A/D converter has its own particular characteristics, and they can be almost randomly different sometimes.

Now, if you want to step outside of the real world for a moment and discuss ideal 48 kHz recording equipment vs. ideal 44.1 kHz recording equipment, then that's a different kettle of fish: There'd be no difference audible to most humans, since most humans can't hear the frequency range between 22.05 and 24 kHz--and that's the only region in which ideal recorders would differ.

But I'm assuming that the question is about practical recording systems. If your eventual "delivery medium" is audio CDs, since those are always at 44.1 kHz, in principle you do yourself no good (and you will do yourself at least a wee bit of harm from an s/n standpoint) by recording at 48 kHz and then converting to 44.1 kHz. in principle the slight sonic advantage that 48 kHz could have over 44.1 (for those very few people who hear 18, 19, 20 kHz and those very few recordings that actually have significant signal energy at those frequencies other than distortion and noise) is thrown away completely when you convert to 44.1.

In practice your mileage may vary, however. From my studio days I can recall one very widely-used (at the time) pro DAT recorder (the "two-part invention" Sony PCM-2500) that had pretty good 48 kHz input filters and not such good 44.1 kHz filters. If that happened to be the only deck you had available, then yes--you'd have been better off recording at 48 and converting to 44.1 in software, even though PC-based software to do that wasn't widely available at the time.

Fortunately that deck was discontinued many years ago now. It was a real example of how the quirks of particular equipment can fool honest people with good ears into thinking that something is true in general when actually, it's not. A lot of studios had that deck, and careful engineers sometimes concluded that "48 sounds better than 44.1" although the very unequal quality of the particular filters on that particular model caused essentially all the difference in sound quality between those two sampling rates. With other decks--especially later models with better A/D converters--the audible difference became far less pronounced or even vanished entirely.

--best regards

[bhakti]

thanks DSatz... always wanted the low down for that... +T
always loved this debacle of 48 vs. 44.1
anymore talk is appreciated... 

[Nick's Picks]

DSatz....
Zen posts !!!

+T

[Belexes]

+T DSatz. I never skip your posts. One of the most well-informed on the board.

[datbrad]

My understanding of the difference between mastering at 48 versus 44.1 has more to do with the analog anti-alaising filters in front of the A/D stage than it actually does with the digital difference.

Theoretically, 44.1 can reproduce frequencies up to 22.05khz and 48 up to 24khz. However, since there is no such thing as a "perfect" analog brink wall filter, it has to start rolling off early, to make sure that the analog signal is completely attentuated at the Nylquist frequency, to prevent alaising.

So, the filter in an A/D set at 44.1 starts to act on the analog input at 20khz, and rolls off so it can completely attenuate the signal by the time it hits 22.05khz. When the A/D is set to 48khz, the filter starts to act on the analog input signal at 22khz, and rolls off so it can completely attenuate the signal by the time it hits 24khz. You will notice this where recorders show frequency response specs for 44.1 maxed at 20khz, and 48 maxed at 22khz, to account for the analog filters impact on the signal.

Looking at even higher sample rates, the filters are even less taxed. This logic to me leads that a signal recorded at 48khz or higher when resampled in a computer to 44.1khz will have none of the roll off that a signal recorded at 44.1khz could have, depending on the quality of the anti-alaising filters. This means that the resampled signal to 44.1khz can attain the theoretical linear 22.05khz maximum, where the mastered 44.1khz signal's response will be flat only up to 20khz.

In practice, I have tried running 44.1khz for the 1st set, and 48khz for the 2nd set, and resampled, the 48khz sample has cleaner high end that seems more extended than the 44.1khz master. I think if you a using software with a good high quality sample rate converter, using 48khz or higher is best, to my ears. And, my ears being human, it is physically impossible for me to hear any signal above 20 khz anyway, so amost all of this discussion is mostly academic.

Hope this helps!