mixing boards

[mazz]

I'm not sure that I can offer a very scientific explanation to back up my statement. If you look at the frequency response of the human ear, it does not hear all frequencies within the audible range at the same amplitude, there are roll-offs at either end of the spectrum and this situation is exacerbated by factors such as age. One of the reasons for the Loudness button on some receivers (do they still have them?) was to boost the low and high frequencies when the music was playing at a low volume to compensate for the ear's perception of those frequencies at lowered volumes. In other words, the ear does not hear sound in a linear fashion, the response graph is a curve with roll offs at the high and low end and a bump from around 3-6Khz (kind of like the response graph of an SM58 mic). Also, when the ear hears a very loud sound, it starts to distort the sound and compress and shut down. It does not turn off completely like a switch and the graph of the response is probably a steep curve but not a straight line, again a non-linear response.Analog tape does something similar when overloaded, it starts to compress the sound but the response of the tape to the overload is not linear, like the response of the human ear. The tape compression does something to the sound that can be pleasing to the ear, I'm not sure exactly why but my feeling is that it's response to overload is similar to what the ear experiences and we can relate to it.Digital, on the other hand has a pretty ruler flat frequency response (limited by the quality of the Analog to Digital converters, of course, there's analog again!) across the entire audible spectrum which is something that doesn't occur naturally in the analog world (the world we live in). The highest frequency reproducible by the system is determined by the sampling rate. When digital is overloaded, there are no more bits available to reproduce sound so it just shuts down, creating that terrible sound we've all heard. There's no way to creatively overload digital like there is with analog, hence the proliferation of analog tape simulators and tube gear. The sharp edges of digital are due to it's ability to reproduce transient information much more accurately than analog (given good quality converters). For many things, that's a positive improvement over analog, but for a lot of things the ear would rather hear a nicely smeared transient. IMO it's much less stressful on the body.It's hard to put these thoughts in to words and I'm sure I'll get ripped to shreds on some of my wacko theories but I truly think that digital is still striving to provide the warm, fuzzy feeling that analog does by nature. The controversy still rages.Mazz

[ernstinen]

I remember reading an article by Bob Moog who said that analog tape @ 30 IPS on a pro machine records up to 45 kHz.Here's a quote from Pro Sound News:Listening to a first generation 30 IPS 1/2" tape is like watching a fresh print of Star Trek at the Astor Plaza in New York. I believe that a finely-tuned 30 IPS 1/2" tape recorder is more accurate, better resolved, has better space, depth, purity of tone and transparency than many digital systems available today. Empirical observations have shown that you need a nominal "24-bit" A/D to capture the low-level resolution of 1/2" 30 IPS. (If truth be told, the best converters only approach about 19-20 bit resolution in practice.) It can also be argued that 1/2" tape has a greater bandwidth than 44.1 kHz or 48 kHz digital audio, requiring even higher sample rates to properly convert to digital. Listening tests corroborate this. 30 IPS analog tape has useable frequency response to beyond 30 kHz and a gentle (gradual) filter rolls off the frequency response. ******************************************So, even though most people can't hear beyond about 20 KHz, you can feel the "air" and sense the higher frequencies in an analog recording.I've argued this before with our resident guru Nick Batzdorf, who poo-poos the fact 'I' can hear up to 26 KHz, but I know what I hear! So the bottom line (beyond the positive tape-saturation qualities and low-end response of analog tape) is that if you record digitally, in order to compete with the frequency response of a quality analog recording, you need to use the highest digital resolution possible.HD DVD discs support encoding in up to 24-bit/192 kHz audio for two channels. While even the highest tech movies only have 24-bit/48 kHz audio, I'm sure pretty soon you'll throw out your CDs and go to HD DVD if you're an audiophile. Ern

[jh]

Here´s my scientific explanation Quote:The sharp edges of digital are due to it's ability to reproduce transient information much more accurately than analogI think it´s just the opposite. Digital (waveform) has these little "steps" which are the bits, when analog is just one smooth continuous wave. Digital is like a stairway and analog is like a hill. Quote:(If truth be told, the best converters only approach about 19-20 bit resolution in practice.) The digital "stairway" has only 24 steps=bits, and when the signal is on the lower steps (lower in volume) the signal has a lower resolution and more distortion, and when it "comes up the stairs" (louder in volume) it has less distortion and more resolution, so that way it´s linear like Mazz said. Check out www.digido.com Quote:So, even though most people can't hear beyond about 20 KHz, you can feel the "air" and sense the higher frequencies in an analog recording.It´s not just the air, extended frequency response affects the lower frequencies too (even the bass). But...everything ends up into a mp3 player, so it gets ruined anyway - JH

[ernstinen]

Quote:It´s not just the air, extended frequency response affects the lower frequencies too (even the bass).True. I thought I mentioned that, but maybe not! Quote:But...everything ends up into a mp3 player, so it gets ruined anyway I was GOING to mention that! 1.) mp3: Crap2.) CD: Marginal3.) 48k DAT: O.K.4.) 24/88.1: Decent5.) 24/96: Good6.) 24/192: Close7.) 32/192: Closer8.) ??/???? Holy GrailErn

[stick]

Quote:1.) mp3: Crap2.) CD: Marginal3.) 48k DAT: O.K.4.) 24/88.1: Decent5.) 24/96: Good6.) 24/192: Close7.) 32/192: Closer8.) ??/???? Holy GrailErn Can you really hear the difference between 24/88.1 and 24/96? That's amazing. Not that I've ever tried (that's a tough thing to test without two high end identical DAW setups), but I'd be surprised if I could, and I've been at this a long time.

[ernstinen]

Quote:Can you really hear the difference between 24/88.1 and 24/96? That's amazing. Not that I've ever tried (that's a tough thing to test without two high end identical DAW setups), but I'd be surprised if I could, and I've been at this a long time. Well, Stick, old bean, I was being somewhat glib with my rankings, but I'm older than you so I deserve the right! Seriously, the last time I did a listening test between 24/88.1 and 24/96, I could only hear a very slight difference. Bit rates make a BIG difference.BTW, there are a couple producers off the top of my head, Rick Rubin and Bill Ham, that make great sounding CDs. I don't know how they do it, but my "marginal" rating goes up when guys like that are behind the board! --- I'd love to hear the original masters of their stuff --- I'll bet you'd soil your drawers listening to them on a good system! Ern

[stick]

I did a record years ago on a ProTools 16bit Mix system and the guy I did it for still tells me it his best sounding record. We've done 3 for him since then on an HD rig at 24bits. I think the recording system is a very small part of the picture.

[ernstinen]

Quote: I think the recording system is a very small part of the picture. I agree, Stick. I'm no tech-head by any means. Whatever sounds good, do it! As a matter of fact, some of my best-sounding recordings were done on a 1/2" analog 8-track, using a track for time code to sequence the keys. Go figure! Ern

[aubreyz]

First of all, here is an interesting thread from a few months ago on the Pro Tools forum for any of you tech heads with some time to kill The goggles thing is interesting, though probably not relevant at the end of the conversion process. http://duc.digidesign.com/showflat.php? ... t=1&vc=1To answer the original question, I use a control surface - not a real mixer anymore. If I had the budget, I'd love to have a massive, suped up Neve console, but I'd also love to have a Porsche - though I don't really NEED it .I've been in this game a while. Recorded my first demo in '82 (yikes), and have been doing this for a living off and on since about '87. I had one of the first DAT machines in the US (got it gray market before they were sold here). I beta tested one of the first ADATs through a rep friend. All that to say, over the years I've had lots of opportunities to test stuff as new technologies rolled out.I remember when CDs first hit. To me they sounded awful. Thin, metallic, tiny. Come to find out, CDs weren't as bad as the early players were. Anybody remember the rumors about coloring the edges of a CD with a blue magic marker to improve the sound I actually tested that If I saw the CD go in, I could hear a difference. In a blind test, I was about 50/50.To make a two decade story short, IMHO the biggest difference one will actually hear has nothing to do with sample rates, but it's the quality of the converters. Before I bit the bullet on the Pro Tools gear, I had a MOTU 828 mkII interface. Sounded good. I did blind tests up to 96k. Couldn't consistently tell a difference. However, when the Digidesign 192 showed up, I redid those tests. I COULD consistently tell a difference between 96k and lower rates, but even the lower sample rates sounded better than the MOTU. Currently, I have an RME interface for my sample playback computer. It too sounds better when clocked from the 192.I can't say that I understand all of the technical aspects of digital audio, but there IS something that happens at higher sample rates - even when processing samples that were recorded at lower bit rates. Maybe it's internal processing. Maybe it's ultrahigh frequencies. Maybe it's in my head. However, the difference is marginal enough that 4 out of 5 dentists surveyed couldn't tell a difference. On some things, I can tell a difference in a blind test. On others I can't.Bottom line, a higher sample rate is not going to be significant enough to be a deal killer. If you are recording a great song, with great sounds, and know what you are doing, that's the key. I love all the gear I have, but I'm skilled enough with duct tape that I would bet you that with enough time and effort, with any current software or interface, I could produce a broadcast quality recording that would rival what I'm producing now. Yeah, the big bucks stuff "sounds" better. But a great mix is more of a difference than that marginal, ethereal holy grail of fidelity. It's not the gear. It's not the sample rate. It's the music that matters. A great engineer is just making music, not crunching numbers.Aub

[stick]

Yes. What he said. Only louder. One louder.