keithd@cadovax.UUCP (Keith Doyle) (08/09/85)
.......
I am posting this to both net.music.synth and net.analog because I
thought that there might be experts in either group that could help
answer these questions.
I am considering designing a new music synthesizer product, and
being a little behind in certain subjects, I have a few questions
that perhaps some of the gang out there could answer:
1. What are the advantages/disadvantages of linear vs companding DACS?
Are the choices compounded by things like:
a. requiring A/D as well as D/A?
b. manipulation of values via standard DSP processors, vs
a strictly sampling system? (in other words, can a DSP
make sense out of a companded value and manipulate it
effectively without first having to un-compand it, and
then re-compand it for output?).
2. What, in the recording industry, is considered 'studio quality'?
In particular, I am talking about the DACS again, (I'm assuming that
a nyquist somewhere around 48khz is acceptable, correct me if I'm
wrong.) What I want to know is, how many bits, signal/noise etc.
And, is there a difference between 'studio quality' and 'acceptable'?
I want to know the arguments for 10-12-16 bits etc. if there are any
besides cost.
3. MIDI would seem to be a move towards modular synthesizer products.
To me, this would imply 'component' synthesizers. Have we actually
gone that direction? Can I go out and by a keyboard (JUST a keyboard)
to hook up to some sound generation hardware via MIDI? Can I go out
and by sound generating hardware (sans keyboard) to hook up to existing
keyboard equipment via MIDI? If not, am I misinterpreting the
motivations behind MIDI? If we are not yet at the totally
'component' synthesizer point yet, does it seem like the market
is heading that direction?
4. What is the importance (in the studio) of SMPTE time coding, where
related to synthesizers. I would think that perhaps videos of
commercials would find it useful to be able to drive your 'sampling'
effects box or vice versa to provide accurate synching of the sound
and video.
Thanks in advance for any input. Right now, I'm primarily trying to
find out what features are required in a serious product, while still
trying to keep the focus on low cost (if they are not totally mutually
exclusive.
Keith Doyle
# {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithdjeq@laidbak.UUCP (Jonathan E. Quist) (08/13/85)
> 3. MIDI would seem to be a move towards modular synthesizer products. ... > Can I go out and by a keyboard (JUST a keyboard) > to hook up to some sound generation hardware via MIDI? Can I go out > and by sound generating hardware (sans keyboard) to hook up to existing > keyboard equipment via MIDI? Yamaha has a fairly extensive line of MIDI products, including a standalone keyboard (the KX-1, I think) with pressure and velocity sensitive keys. It's basically the same keyboard used in the DX-7 synth. Yamaha's TX-816 is a small rack mount box containing the sound production hardware equivalent to slightly more than 8 DX-7's. > 4. What is the importance (in the studio) of SMPTE time coding, where > related to synthesizers. I would think that perhaps videos of > commercials would find it useful to be able to drive your 'sampling' > effects box or vice versa to provide accurate synching of the sound > and video. Roland has a sync box (the SBX-1?) which will convert MIDI to SMPTE, and vice verse. It also allows the operator to "conduct"; tapping on a keboard switch controls the rate at which the box sends out MIDI tempo information. A friend recently used it to add a soundtrack to a video. To avoid verbosity, I'll simply say that he described the use of SMPTE as indispensable in serious studio work. DAC Caveat: If you are using digital synthesis, the algorithm you use can potentially introduce enough noise to make the best DAC's sound like a crystal radio in a thunderstorm. The noise floor of the Yamaha TX-816 varies drastically between voices. Just one more thing to keep in mind. Jonathan E. Quist ihnp4!laidbak!jeq ``I deny that this is a disclaimer.''