mdoerner@magnus.acs.ohio-state.edu (Mike R Doerner) (05/13/91)
Seeing this talk about digitizing has given me a few questions...
1.) My friend has a bass guitar. I was wondering if I could
"digitize" him with a direct rca to amiga hook up. Is it possibe to hook
him up in such a way as to have him play a note, have it digitized, and
put as direct output in "real time"???
2.) Is it possible to take "fuzzy" & "hissy" studio recordings
and have them re-recorded as "clean" without the hissing & fuzz (in
other words, recording w/o dolby equipment & cleaning it up.)
Please respond by mail, because if these questions are common ones,
I hope that noone will get flamed at me. (I just got my amiga 2 weeks ago)
--
Mike Doerner | doerner.1@osu.edu | mdoerner@magnus.ircc.ohio-state.edu
----------------------------------------------------------------------
You can't hug you children with nuclear arms,
but you can sure keep 'em warm!!!othomas@athena.mit.edu (Oliver J. Thomas) (05/14/91)
In article <1991May13.022242.13462@magnus.acs.ohio-state.edu> mdoerner@magnus.acs.ohio-state.edu (Mike R Doerner) writes: > 1.) My friend has a bass guitar. I was wondering if I could > "digitize" him with a direct rca to amiga hook up. Is it possibe to hook > him up in such a way as to have him play a note, have it digitized, and > put as direct output in "real time"??? Yep, you can do that. Check out a program called "SuperEcho" on FishDisk It will do what you want and more, like special effects (hence, the Echo in the name...) > 2.) Is it possible to take "fuzzy" & "hissy" studio recordings > and have them re-recorded as "clean" without the hissing & fuzz (in > other words, recording w/o dolby equipment & cleaning it up.) This is a little more tricky. Basically, to clean up a signal, what is usually done is filtering (digital or analog) out those frequencies where you suspect most noise to be concentrated, and, in some cases, convolving the waveform by a smoothing function to take out the "hard edges" associated with noise. That's why Dolby NR gives a somewhat muffled sound to recordings made without NR. Now, to do this filtering on the Amiga, the basic procedure would involve transforming the incoming signal into the Frequency Domain (through Fast Fourier Transforms, usually), multiply that by the appropriate filter function, and by a smoothing function, the reverse transform it to get a time signal back, which is the cleaned up audio. Sounds simple enough, and the algorithms aren't that hard, but don't expect your Amiga to do it in real time. If you just want to clean up recordings, though, real time should not be an issue. > Please respond by mail, because if these questions are common ones, > I hope that noone will get flamed at me. (I just got my amiga 2 weeks ago) ^^^^^^ If you get flamed for a question like this, the discussion group would be in sorry state indeed. Don't feel relucant to ask valid questions. The only dumb ones are those never asked (someone once said...) Hope the above explained a little of the kind of stuff involved. If you need some specifics, like pointers to references or code, feel free to send me mail. Oliver Thomas othomas@athena.mit.edu -- --------------------------------------------------------------------------- Oliver James Thomas, othomas@athena.mit.edu, Telephone: x5-9385
othomas@athena.mit.edu (Oliver J. Thomas) (05/14/91)
I wrote (just now): > Yep, you can do that. Check out a program called "SuperEcho" on FishDisk > It will do what you want and more, like special effects (hence, the Echo in > the name...) Sorry about that. I went back to look up the number of the Fish Disk, and then forgot to put it in the message. Talk about wasting bandwidth. Anyway, SuperEcho is on FD# 300. Sorry for the screwup. Oliver Thomas othomas@athena.mit.edu -- --------------------------------------------------------------------------- Oliver James Thomas, othomas@athena.mit.edu, Telephone: x5-9385
kcampbel@uafhp.uark.edu (Keith Alan Campbell) (05/14/91)
The second technique you mentioned, the one about cleaning up recordings, cannot yet be done on an Amiga, since it requires 16 bit or greater sampling, which will not be available until some of the promised 16 bit audio samplers are commercially available, such as the AD1016 by SunRize, which should be available later this year. I have it on good authority that a program called "DeNoise" from the CARL digital audio distribution, is being considered as a port for this card, which uses the DSP56001 processor as an audio coprocessor. Don Kennedy Vision Quest Systems
kudla@nuge107.its.rpi.edu (Robert J. Kudla) (05/14/91)
othomas@athena.mit.edu (Oliver J. Thomas) writes: >> 1.) My friend has a bass guitar. I was wondering if I could >> "digitize" him with a direct rca to amiga hook up. Is it possibe to hook >> him up in such a way as to have him play a note, have it digitized, and >> put as direct output in "real time"??? >Yep, you can do that. Check out a program called "SuperEcho" on FishDisk >It will do what you want and more, like special effects (hence, the Echo in >the name...) Normally I wouldn't mention this, but since the subject is "Perfectsound"... WARNING!! Virtually *no* freely redistributable utilities such as SuperEcho work with PerfectSound III! PS3 has software gain control and rather than defaulting to a reasonable level, it simply doesn't work with software not specifically coded to use the gain control feature! On the bright side, there are several audio programs that do lots of neat things including realtime EQ and effects with PS3, but they're commercial: AudioMaster III does it, I think, and whoever makes PerfectSound has a really nice one as well. They generally go for $80 or so and are probably a better idea if you're serious about using the Amiga as an 8-bit sampler. If you're just messing around though, I'd recommend going for one of the other samplers (the Audiomaster people - Oxxi is it? - are making one now I think) and a PD program like SuperEcho. Good luck.... -- Robert Jude Kudla <kudla@rpi.edu> No more bars! No more cages! Just rollerskating, disco music, and the occasional light show....
mwm@pa.dec.com (Mike (My Watch Has Windows) Meyer) (05/14/91)
In article <2-_hj1.@rpi.edu> kudla@nuge107.its.rpi.edu (Robert J. Kudla) writes:
Normally I wouldn't mention this, but since the subject is "Perfectsound"...
WARNING!! Virtually *no* freely redistributable utilities such as SuperEcho
work with PerfectSound III! PS3 has software gain control and rather than
defaulting to a reasonable level, it simply doesn't work with software not
specifically coded to use the gain control feature!
It's worse than that. PS3 does sample-and-hold, and requires a bit in
the parallel interface to be toggled to trigger the sample. The PD
utilities expect the sampler to have the "current" value, so the
sample is never take. Because they are now using two bits on the
paralle port to control the sampler (the other one is used for gain
control), the extra two bits of incoming data are in the printer
status bits. So you have to build an 8-bit sample, which the PD stuff
doesn't do.
Because the people at SunRise were basically unwilling to help (other
than providing a library they don't consider good enough to use in
their own software), I ditched my PS3, and will _not_ buy products
from ScumRise until that policy is demonstrably changed.
<mike
--
Il brilgue: les toves lubricilleux Mike Meyer
Se gyrent en vrillant dans le guave, mwm@pa.dec.com
Enmimes sont les gougebosqueux, decwrl!mwm
Et le momerade horsgrave.ewilts@janus.mtroyal.ab.ca (Ed Wilts) (05/15/91)
In article <OTHOMAS.91May13192836@m34-501-4.mit.edu>, othomas@athena.mit.edu (Oliver J. Thomas) writes: > In article <1991May13.022242.13462@magnus.acs.ohio-state.edu> mdoerner@magnus.acs.ohio-state.edu (Mike R Doerner) writes: > >> 2.) Is it possible to take "fuzzy" & "hissy" studio recordings >> and have them re-recorded as "clean" without the hissing & fuzz (in >> other words, recording w/o dolby equipment & cleaning it up.) > > This is a little more tricky. Basically, to clean up a signal, what is usually > done is filtering (digital or analog) out those frequencies where you suspect > most noise to be concentrated, and, in some cases, convolving the waveform by > a smoothing function to take out the "hard edges" associated with noise. > > Now, to do this filtering on the Amiga, the basic procedure would involve > transforming the incoming signal into the Frequency Domain (through Fast > Fourier Transforms, usually), multiply that by the appropriate filter > function, and by a smoothing function, the reverse transform it to get a time > signal back, which is the cleaned up audio. Sounds simple enough, and the > algorithms aren't that hard, but don't expect your Amiga to do it in real > time. If you just want to clean up recordings, though, real time should not be > an issue. Check out a product called Studio Magic, also from Sunrize. It lets you do all sorts of manipulating of the samples, including FFTs. It will generate 3D graphics of the samples, as well as do some basic editing kind of things like cut & paste, echo, etc. > Oliver Thomas > othomas@athena.mit.edu -- .../Ed Preferrred: Ed.Wilts@BSC.Galaxy.BCSystems.Gov.BC.CA Ed Wilts Alternate: EdWilts@BCSC02.BITNET (604) 389-3430 B.C. Systems Corp., 4000 Seymour Place, Victoria, B.C., Canada, V8X 4S8
kholland@hydra.unm.edu (Kiernan Holland) (05/15/91)
Well so far I have seen ads for Sun Rize's 1000 dollar 560001 Equiped 16/12 bit sound boards and in Amazing Computing (a little more reliable source than Amiga Whirled) there was some mention of a company that did the Back to the Future demo with DCTV as developing a 16-bit sound card for thier Grand Slam SCSI/Multi-function card. Neato, Maybe the fact that the Video Toaster with an Amiga 2500 is considered a mac prodcut, we'll see more of the dynamic cards (for amiga prices, eh!) Later