Posted By
MMS
on 2014-01-08
15:51:22
 |  Re: Sounddigitizer & Samsound V1.0
Yeah, definitely it is almost the same as a reversed Covox Card, I also built for my PC in the 90s, based on ZN427 D/A converter, but it was much simplier than this one. As it is 8 bit, not 4, for a playback via ZN427 + Plussy probably provides better sound than SID or TED digi sound.
At PC it connected to the Parallel port, it required a proper 16MHz 286 PC to able play MOD music with 20kHz sampling, but sounded OK with an amplifier, and I feel like almost Amiga quality (not really, but was close  )
I recently read an article about it.
On Spectrum clones from Russia there were plenty of development on such cards (stereo and quad Covox was preferred), but even Atari XL has such a connection and playback capability with the 1Mhz 6502. (!)
They have trackers, similar to the ones made for SID or emulated SID via TED. Just probably the sound quality is better, and uses patterns, like chip musics.
I just copy here some text from http://tarjan.uw.hu/zxclones_en.htm
QUOTE
"Probably most of you remember to the "poor man's soundcard" of early '90s - that was Covox. Some "scientific" names of the device: Covox Speech Thing or sometimes Covox Plug.
This is a simple digital to analogue converter attached to the parallel port. The signal can be boosted with hi-fi equipments, so both digitised effects and music can produced in quite good quality. Covoxes have some different versions beginning from IC variants to resistor type ones.
Covoxes had stereo and quadro versions also. First one is consist of two mono Covoxes, second is integrating four Covoxes into a small board (name of this device was Quadrofonic DAC).
Ready-made Covoxes were also commercially available named to Disney Sound Source. With decreasing the price of soundcards, Covoxes became less and less important - at least in the PC-world.
Among 8 bit home micros, Covox is widespread still (for example Atari XL, Spectrum, but the excellent products of Russian industry, Elektronika BK and Vector were also enhanced with Covox.). This was supposedly facilitated by the fact, that the AY-8910/12 and YM2148F sound chips did not have Russian analogues. Mono versions are existing, as well stereos. And Pentagon Covoxes a little different from the Scorpion's devices.
Quadro Covoxes named Soundrive (one "d!"). Just as at the PCs, four D/A converters integrated to a small board. First version was engineered by Flash Inc. from Novisibirsk in 1995. It has some different versions as Soundrive Normal, Soundrive Baby and Soundrive Monster. Covox and Soundrive were rather popular among users,who wanted to produce digital effects from the ZX Spectrum.
...
Its modern age reincarnation is called Soundrive TLC7528C. This one is designed by solegstar in 2011, and it was announced on the zx.pk.ru forum as an usual habit with the new Russian devices. It is based on the TLC7258C dual channel D/A converter, from which needs two pieces. The card is ZX Bus compatible, Caro was helped in its creation. It also contains an AY-input to make possible the mixing. First, he made a prototype with PC Centronics plug. In theory, it is works with one piece TLC7225 DAC too, but the developer did not tested it yet. Fully compatible with 1.51 both on software and hardware levels and also with the Profi clone.
Covox and Soundrive's quality is 8 bit. In case of Covox the CPU must divide the signals in time-sharing system to the only port (1x8 bit) or at Stereo Covoxes to two ports (2x8 bit). Soundrive signals can directly ported to each channels (4x8 bit).
Russian games and sound softwares are using the different Covoxes. Greatest disadvantage of the devices, that producing music is completely done by the central processor.
Maximum quality is 10 kHz (with optimisation 12 kHz), if samples and volumes stored in high memory area. If the standard, low memory contains the music, then 15 kHz (or 16 kHz) could be reached.
Special Soundrive music editors: Digital Studio, Extreme Tracker, Flash Tracker, Ultrasonic and SQ Tracker.
Their common points, not connected directly to the machines, but through the UR-4 parallel port interface. Among others, Petr Simandl and Cygnus also published their circuit diagrams on their websites. Last one is on Bytefest 2007 party introduced for publicity the techically quite outdated, but surprisingly good quality converter with the ZN427 chip.
Czech/Slovakian Covoxes are made for playing three channel music, opposite of the Russian four channel devices"
UNQUOTE
So, Spectrum clones are able to play 3 channel music with this.
Well, I can say this hardware is well ahead it's time. As I do not speak fluent German 8or not THAT much) I am not sure, if the playback happens via this HW too? Because then it has CAPABILITES
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