I found PCMAG reviews and searching for info too.

Card is only FM with Ensoniq OTTO wt db?
TMS320C25 DSP is for what? For MPEG compression?

here i found Antex manual:
https://www.scribd.com/document/324516037/ANTEX-Sound-Cards
Z1 card ID is 19
Z1E card ID is 27

from 1996 site:
Z1E:
https://web.archive.org/web/19961028092955/ht … /specs_z1e.html
https://web.archive.org/web/19961028092813/ht … m/prodguide.pdf
https://web.archive.org/web/19961028092759/ht … /prodguide.html

Antex Z.Wav Plug in 16-bit wavetable MIDI sound module for Antex Z1e digital audio adapter. General MIDI compatible, Z.Wav features 32-voice polyphony and 16-part multitimbral capability with 4MB of sampled sounds $195

No info about Z1.

But some details about Z1E:
https://web.archive.org/web/19961028092059/ht … com/audio3.html

And SX-9 card for MP2 sound:
https://web.archive.org/web/19961028092051/ht … com/audio2.html

Here are drivers and sdk.
Source: https://groups.google.com/forum/#!search/ante … Ss/4NNXXYjUGwAJ

Antex Software Development Kit for Intel Platform
https://web.archive.org/web/20031005012738/ht … K_i386_V332.exe

Antex Application Software
All Windows Operating Systems (except DOS & 3.1)
Download the latest version of the Mixer, Demo, and Meter. apps-v1058-x86.exe (644k)
https://web.archive.org/web/20031005012738/ht … s-v1058-x86.exe

Support: SX-3, SX-7, SX-9, SX-12a, SX-20, SX-22, SX-23e, SX-33 and Z1e. File: 95drv400g2.exe
https://web.archive.org/web/20031005012738/ht … /95drv400g2.zip

I found and bought this Antex SX-33 a while back. Pretty sure it uses the same board as the Z1/Z1e. Even a place for an OPL3 chip.

This site has the MS-DOS TSR for the Antex cards which is unavailable from the archived Antex site:
http://pm-systems.com/pristine/support/

Found a poor quality photo of the z.wav daughtercard. You can read about it more in Radio-World-1994-09-07 and Electronic-Musician-1993-10. It's another Waveblaster compatible board. Contrary to what's in the PC Mag review, it's written, that it contains 4 MB of samples, which would make it bigger than on the other Ensoniq OTTO based boards. The PC Magazine review linked in previous posts mentions it "lacked the sparkle found on other chipsets" which to me describes the Soundscape, so they might have used a similar sample set. There's no editor, so it looks like it's limited to General MIDI operation.

There's one additional quirk, the daughtercard has more than a WaveBlaster connector. If you look in the Antex sound cards Manual, you can see, that it connects to a Z1/Z1e card via a Waveblaster header (J2), a "MPU-401" header (J11) and a DSP header (J12). The SX-3/33 on the other hand use only the "MPU-401" header and the DSP header, so apparently there's no Waveblaster compatibility. A dedicated DPS connections sound similar to the optional DSP on a Soundscape Elite.