[comp.sys.amiga] WARNING: Gadget Alert!

derhak%cs.utah.edu@wasatch.utah.edu (Max W. Derhak) (09/08/89)

Hello all!

I just thought that I would let you all know that there is a new gadget out
that does wonderful things for our favorite computer.  It's called a 
Microreverb II, and is produced by a company called Alesis.  It is really
only a digital reverb processor, but it makes everything pumped into it
sound so totally terrific.

About a month ago I was at a friends house, and he has a lot of audio equip-
ment, including one of these reverbs.  He had it hooked into the same stereo
that his computer was hooked up to.  My brother wanted to see if his disk of
Artic Fox worked on his computer. (It doesn't on ours :-(.)  It worked fine,
but oh what a difference it made to the intro music.  It actually sounded
like the sound was comming from an organ IN A CATHEDRAL.

We decided to save up our $$$ and get one ourselves.  We just got it yesterday
and it make just about EVERYTHING sound better.  In essence it doubles the
effective number of channels that the Amiga has, because even when a voice is
finished with a note, the reverb takes the sound out further giving it a
little bit loger decay.  Meanwhile the voice can start a new note.  Thus
two notes are being heard from the same voice.  In adition it also mixes
to a small extent the left and right channels so the sound isn't so polar.

We have spent a little time listening to demo's and things. To see how
such and such will sound.  It greatly improves sounds and instruments which
are short and abrupt.  One good example is drums.  They come alive and sound
more like real drums.  Music isn't the only thing that is enhansed.
Explosions now have DEPTH!

The reverm comes with 16 settings which are adjustable with via a mix control.
You can also control the input level and output level so it also acts as a
pre-amp between the computer and your stereo.  By turnig the mix control
completely to the left you end up with no change to the audio output, so
it's real easy to see the drastic difference this thing makes.

The Microreverb II retails for $199, but we got ours on sale locally here for
$149.  I dont know about mail order prices, but you can only find these
little black boxes in places that sell music equipment.  We had a troublesome
time finding one, because our friend bought his used from someone else.

Last of all I'd like to say that I have NO affiliation with Alesis.  I'm
just a satisfied customer that thinks that this makes the Amiga's sound
even better that it already is.

==========================================================================
 Lekarz  THE //\/\    //| \ /  #  Max Derhak (derhak@cs.utah.edu) :^>
   od    \\ //    \  //-|  X   #  Oh Yeah?  If you think that was neat
  Raju!   \X/      \//  | / \  o      wait till you see THIS!

riley@batcomputer.tn.cornell.edu (Daniel S. Riley) (09/08/89)

In article <3278@wasatch.utah.edu> derhak%cs.utah.edu@wasatch.utah.edu (Max W. Derhak) writes:
>I just thought that I would let you all know that there is a new gadget out
>that does wonderful things for our favorite computer.  It's called a 
>Microreverb II, and is produced by a company called Alesis.  It is really
>only a digital reverb processor, but it makes everything pumped into it
>sound so totally terrific.

Reverb can very effectively hide a lot of defects (especially poor or noisy
sample looping, noisy signals, or lack of dynamics).  This is well known in 
sound recording and electronic music.  Standard advice for someone shopping 
for a sampler or synth with a built in reverb is to turn the reverb off 
before doing any critical evaluation of the sound quality--otherwise, the
reverb hides most of the defects.

Anyway, I have my Amiga running into a mixing board with a Korg DRV2000
programmable reverb on one of the effects loop, and it is great for livening
up those dead sound tracks.  Best fun was changing the "room size" when I
played Bard's Tale to match the location...now if one of these games just
sent midi patch change messages out the serial port whenever you changed
location, it could all be automatic.  But I don't suppose there's a big
constituency for this particular feature :-).

-Dan Riley (riley@tcgould.tn.cornell.edu, cornell!batcomputer!riley)
-Wilson Lab, Cornell U.

set@xanadu (Scott Townsend) (09/08/89)

In article <3278@wasatch.utah.edu> derhak%cs.utah.edu@wasatch.utah.edu (Max W. Derhak) writes:
>Hello all!
>
>I just thought that I would let you all know that there is a new gadget out
>that does wonderful things for our favorite computer.  It's called a 
>Microreverb II, and is produced by a company called Alesis.  It is really
>only a digital reverb processor, but it makes everything pumped into it
>sound so totally terrific.
>
(details deleted)

I haven't done anything with the audio device, but shouldn't it be possible
for a new/possibly massively changed audio device to do digital reverb within
the machine, instead of buying an add-on?  Maybe not quite as great in sound
quality, but it could provide some reverb and maybe stereo imaging effects.
(speculation)

I'm thinking along the lines of audio.device remembering the previous N samples
sent to the D/A (somehow in sync with the DMA) and altering the samples yet
to some to get the reverb effect.  Maybe 8 bits would be too much quantization
error in the reverb components.  Anyone care to comment? experiment?

-----------------------------------------------------------------------------
Scott Townsend			   ...!{cwjcc,decvax,pyramid,uunet}!abvax!set
Polymath Corporation, currently working for (but not representing)
Allen-Bradley Company 747 Alpha Dr. Highland Hts. OH 44143 USA (216) 646-5233

mark@xrtll.UUCP (Mark Vange) (09/11/89)

In article <860@abvax.UUCP>, set@xanadu (Scott Townsend) writes:
> 
> I haven't done anything with the audio device, but shouldn't it be possible
> for a new/possibly massively changed audio device to do digital reverb within
> the machine, instead of buying an add-on?  Maybe not quite as great in sound
> quality, but it could provide some reverb and maybe stereo imaging effects.
> (speculation)
> I'm thinking along the lines of audio.device remembering the previous N samples
> sent to the D/A (somehow in sync with the DMA) and altering the samples yet
> to some to get the reverb effect.  Maybe 8 bits would be too much quantization
> error in the reverb components.  Anyone care to comment? experiment?

The problem is that while you are piping the "reverbed" (I shall call it
digested) sound, you must also keep playing the sound which came down the
pike more recently.  To do this you must either break the sound down into
it's spectrum, and do a bit of addition, along with FFT there and back, or
you must double your playback rate, and "mix" the new sounds with the old
reverbed stuff.

The former is probably not practical except in the case of a dedicated 
playback system because it would be quite CPU intensive.  The
second is still overly simplified, because the new sound would have to be
fed back into the digested signal and mixed with the older stuff, although
this could be accomplished by an algorithmic hack rather than the FFT
approach, especially if you didn't mind a constant rate of fade.

-- 
Mark Vange				Phone Death Threats to:
PAS Systems - "Plain and Simple"	(416) 730-1352  mark@xrtll
8 Everingham Ct.  North York	"Every absurdity has a champion
Ont, Canada  M2M 2J5		 to defend it." - Oliver Goldsmith