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Re: GG: CBC Recordings -- the best possible?



At 14:57 18/07/98 -0500, John P. Hill wrote:
>
>On Sat, 18 Jul 1998, Tim Conway wrote:
>
>> (1) What exactly do CEDAR and NoNOISE do?
>Whoa....there's a lecture or two. Here goes, Tim:
>
>1. CEDAR and NoNOISE are digital algorithms that work in conjunction with
>hard-disk based editing systems like SADIE (in the case of CEDAR) and
>SONIC (NoNoise). These systems are digital "workstations" that are used
>for editing and processing music signals in a variety of ways. Both CEDAR
>and NoNOISE use intelligent algorithms to lower or eliminate background
>noise from older recordings. The noise being removed comes mostly from
>analog tape that was recorded at lower tape speeds (7.5 or 15 ips)
>without noise reduction systems (like Dolby A or SR). These modules can
>also do de-clicking to remove spurious clicks and pops in the recording,
>such as might be produced when transfering from an old vinyl LP or 78.

John's explaination is good and reminds me of a project that I have been working on for a couple of months. One of my favourite recordings at the moment is the live Salzburg recording of the Goldbergs and Sinfonias [There is a really wacky problem in the middle of the Sinfonias where the recording sound changes substantially - it sounds like a set of microphones stopped working, or Glenn poured some butter into the piano in the middle of the performance]. After reading an article about Marcel Duchamp's Gap Music (he is interested in the gap between Art and Noise), I decided to edit the first couple of Goldbergs on the studio hard disk and remove all of the notes. I call the piece "Glenn Gould doesn't play the non-Goldberg Variations not in Salzburg". The new piece is rather nice as one can concentrate on the room ambience, as well as the faint echoes of the piece itself. It did take a long time to do - about 5-10 mins per note attack.
John's comments have led me to rethink my strategy a little - Why not let the computer do all the work? I am basically a lazy editor, so I may just run through the sounds as .wavs, calculate the fft and then filter out the strongest frequency with a steep slope. The interesting bit would be to edit out the notes, and then with the sounds that are left, change the phase on them and then combine them with the original recording. Wouldn't that get rid of all the background noise :->


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Bruce Petherick |
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Bringing musicology to the masses... |
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Harry Conick Jr. is the Hanson of the |
Jazz world. |
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b.petherick@pgrad.unimelb.edu.au |
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