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View Full Version : Lifesize Sound Enhancer, Covox clone?



A-ko
April 25th, 2017, 05:23 PM
Hi all. Just recently uncovered several of my childhood PC games that we thought had been lost forever. One included a Lifesize Sound Enhancer, which seems to be a basic parallel port D/A converter, similar to the Covox Speech Thing. We always had a Soundblaster so we never needed to use it. Has a 25-pin male port on one size and a mono RCA output on the other.

The question is, will a program looking for a Covox in COM1 recognize the Enhancer as the same thing, or is there more to it than that? I tried an install of Sim City with Covox specified as the sound output device, but its not detecting the Enhancer.

Is there actual circuitry that makes a Speech Thing recognized specifically as such inside one, or how does it work? I always thought they were just simple D/A converters and wouldn't have any special hardware inside, but i have a very basic understanding of anything like this.

Also, any games specifically that work with it, if i can't get it to work as a Covox instead? I'm trying to use it on my Zenith Z-158, which is an XT clone that i recently swapped a V20 chip into.

Excuse this thread if there already is one covering this, but i tried searching for "lifesize" and came up with zero results.

Thanks for the help!

Caluser2000
April 25th, 2017, 07:28 PM
Excuse this thread if there already is one covering this, but i tried searching for "lifesize" and came up with zero results.

Thanks for the help!Using google is far better than the on site search engine fwiw.

kyeakel
April 25th, 2017, 07:53 PM
It is probably very similar to the Disney Sound Source. I have some kids games that use it.

Kipp

Scali
April 25th, 2017, 10:40 PM
A Covox is an extremely simple device, just an R2R resistor ladder hanging from the printer port.
As such, there's no way to detect it. You just need to configure a game and tell it to use a Covox on LPT1 (or whatever other port). If this thing is indeed compatible, sound will come out.

The Disney Sound Source is a more complicated device, and requires some specific handshaking (there's a small buffer of samples on the device, and it plays at a fixed rate of 7 kHz).
People often equate the DSS and the Covox, but they're completely different and incompatible devices.

A-ko
April 26th, 2017, 05:40 PM
A Covox is an extremely simple device, just an R2R resistor ladder hanging from the printer port.
As such, there's no way to detect it. You just need to configure a game and tell it to use a Covox on LPT1 (or whatever other port). If this thing is indeed compatible, sound will come out.

This is what i was hoping, thanks! Maybe i have the wrong port specified. I will do some more experimentation!

A-ko
April 26th, 2017, 08:26 PM
Got it working great with Galaxy Music Player just now. Yep, it's just a normal DAC and works as such. Also tried it as a Disney Sound Source, and while it does still output sound, it's at the totally wrong sampling rate or something. You can kinda recognize what the sound is supposed to be but it's all wrong. So today i learned that the Disney Sound Source is NOT directly compatible with the Covox, as i had previously thought. Unfortunate...lots of misinformation out there! But now i want a Sound Source as well...

Thanks guys!

Trixter
May 1st, 2017, 07:09 PM
The Disney Sound Source is an LPT DAC with a lowpass filter and a 16-byte FIFO chip that drains at a fixed rate of 7 KHz. So, if you try to use a DSS as a generic LPT DAC, it likely won't work. Likewise, software expecting a DSS (mostly Disney-branded software from the early 1990s) will probably sound odd because the output won't be consistent (it outputs a burst of 8+ bytes at a time because it knows there is a FIFO there to catch them, and it's less overhead for the CPU).

So why get a DSS? Because for the software that does support it properly, it's great. A lot of the Disney-branded stuff contracted ESS to produce audio massaged specifically for the device's fixed output rate and filter, and they used that knowledge to compress the audio 2:1 or more without appreciable quality loss. The end result is a lot of speech and music for games that come on a handful of floppy disks, that sounds great through the device, and thanks to the FIFO, it doesn't take as much CPU time away as a regular dumb LPT DAC would.

You can fool the DSS into playing faster rates by bypassing the FIFO: Initialize it, send a byte, initialize it, send a byte, etc. Mark J. Cox's Modplay does this, although the CPU overhead is significant (you're outputting twice as many bytes as would be necessary). I'm not sure what method Galaxy Player uses, but if it sounds goofy (pun intended!) on a plain LPT DAC, it might be supporting it "properly", using the FIFO.

Here's a list of software that supports the DSS: http://www.mobygames.com/attribute/sheet/attributeId,44/p,2/