From: yxl5388@ultb.isc.rit.edu (Fractalman)
Subject: Media Vision AudioPort info/review
Originator: yxl5388@ultb
Organization: Klingon Imperial Fleet
Date: Mon, 12 Oct 1992 18:50:23 GMT

 
Hi all, since I think there was very little info available concerning
the Media Vision AudioPort (parallel port sound adapter) I just went out
and bought one. Here's my little review. If you already know more than
me about it please ignore my ignorance and send me some e-mail. :) This
is about the *Media Vision* AudioPort, there is another similar product
by another company also called the same name.
 
I tested the AudioPort on my T4400SXP (486SX-25) with 2 (soon to be 6)
megs of RAM running DOS 5.0 and Windows 3.1. And I have an NEC-74 CD-ROM
drive hooked up to the parallel port using a MiniSCSI. The CD-ROM drive
is disconnected when using the AudioPort. (See below.)
 
Here are some specs taken right out from the manual:
 
Audio output
Power internal speaker: 0.25 watts
Internal: 1.5" speaker
Power external speaker: 0.5 watts (4ohms)
External: 1/8" mini headphone out
Output level: 8V max p-p
Sample rate: 8-bit mono, 2-22kHz
Dynamix range: -48dB
Signal to noise: -55dB
Frequency response: 20Hz-11kHz
THD: 0.1% @ 1kHz
 
Audio input
1/8" mini microphone jack
Sample rate: 8-bit mono, 2-22kHz
AGC: 20dB min, 100dB max
Input level: 10mV
Input impedance: 10K ohms
Dynamic range: -30dB
Signal to noise: -50dB max gain, -80dB min gain
Frequency response: 100Hz-12kHz
THD: 0.1% @ 1kHz
 
Volume control
3/4" thumb wheel
(the hole on the case apparently wasn't designed large enough for the
thumb wheel and a little plastic is cut off from the sides to make the
thumb wheel fit...)
 
Power requirements
Internal battery: 4 AAA batteries
Battery eliminator: +6V DC (included)
 
Synthesis
Synthesis type: FM
Device: YM3812
Dynamic range: 60dB
Signal to noise: 60dB
 
PC interface
25 pin D-shell (male)
 
Warranty
3 year limited warranty
 
 
I was VERY disappointed to find out that the SoundBlaster and Adlib
compatibility works ONLY inside the DOS box from within Windows. There's
a 386 virtual driver which provides this feature. It also means that you
need a 386sx or higher running Windows in 386 enhanced mode to make the
AudioPort emulate the SB or Adlib. Otherwise the AudioPort comes with
its own Windows FM and WAV driver. After installing the driver the Media
Player works fine for playing both WAVE and MIDI files. Other programs
that make use of the multimedia ability of Windows through the use of
drivers also work fine. (e.g. Monologue, Icon-Hear-It, etc.)
 
If your system can handle games (face it, you want the AudioPort to play
games) running inside the DOS box and if you can stand the slowness then
the AudioPort is almost perfectly compatible. VPLAY (VOC player that
came with the SBPro) works just fine in the DOS box. Programs that play
digitized sounds and depend a lot of hardware timing probably don't work
though, such as MOD players. But those programs normally don't work in
the DOS box anyway. (Out of This World didn't work because of all the
digitized music, Stunts and some other racing games that have high speed
screen update routines play the sound but I don't get any graphics.
Sierra and Dynamix games work fine.)
 
The sound quality is fairly good for a little speaker like that. If I
plug in earphone and listen thru them the sound actually sounds worse. I
haven't tried real speakers yet. The sound is quite clear when playing
FM music or SB compatible digitized sounds separately. However if both
are being played at the same time the sound gets 'muddy' and there's a
slight hissing sound.
 
There is a program called FMPORT.COM (not documented in the manual) on
the utility disk which does provide sound capability under DOS by being
sound.com compatible. But right now the only programs I can think of
that uses sound.com to generate music are Spellcasting 101, the Adlib
Jukebox, and some very old public domain games. I've tried Spellcasting
101 and it works great. I called Media Vision's BBS hoping to get some
info about DOS compatibility but out of about 1,000 messages there were
only 2 messages about the AudioPort and they asked the same question I
wanted to ask. No replies though. The funny thing is that the AudioPort
drivers on the BBS were all downloaded like 600+ times...
 
The AudioPort also doesn't work in conjunction with the MiniSCSI which
wasn't a surprise since both use the parallel port. They would work
together but not simultaneously. I plugged the AudioPort to the
pass-thru printer port on the MiniSCSI. I could access the CD-ROM and
play sounds but programs (such as Bookshelf for Windows) which use both
the CD-ROM and WAV/FM audio at the same time won't function. If you
force it to work it'll read the CD and skip the sound. But after a while
the sound driver starts acting funny and eventually no sounds at all
will come out and Windows needs to be restarted to get the sounds back.
I hope Toshiba will release their expansion port SCSI adapter real soon,
with that the CD-ROM would be able to work without using the parallel
port.
 
If all your sound applications (and games) run within Windows I'd say
that the AudioPort is a pretty good value. The SoundBlaster and Adlib
compatibility is questionable because of the necessity of running the
programs inside the DOS box. I hope they'll come up with a TSR driver
for DOS to provide the compatibility. Creative Labs announced (released
yet?) the PortBlaster which uses the OPL3 chips and is supposed to be
SoundBlaster Pro compatible, except it records only in mono instead of
stereo. And it supposedly has a MIDI interface and 4watts/channel
amplifier. If the PortBlaster works in both DOS and Windows I'll get it
this second.
 
Wow. I'm babbling again, I really should write a book one of these days
so I can babble continuously and people will pay to read it. Well, if
you need more info or have specific questions about anything mentioned
in here (AudioPort, MiniSCSI, whatever) send me e-mail.
 
=Fractalman
yxl5388@ultb.isc.rit.edu