I don't think that adoption of SB16 in games was slower than SBPro's...
and MobyGames seems to agree, let's look at the first five years of each:

SB Pro
1991 - 10
1992 - 76
1993 - 177
1994 - 266
1995 - 317

SB 16
1991 - 2 (well, MobyGames lists "Floor 13" and "Wordtris", mistake?)
1992 - 19
1993 - 78
1994 - 202
1995 - 276
1996 - 323

Though it's true that SB16 usually wasn't used to the max, 16-bit samples occupied more space, and made hardly any difference in SFX.
See also - Re: Creative's intended market for 16 bit audio?

Games started supporting the SB16 as soon as it came out, in the sense that you could select it as a valid option in setup. Whether they were able to fully utilize its capabilities is another matter entirely.

Like you said, 16-bit sound samples take more space, and games were shipping on floppy disks up until the mid '90s or so. Technically, you would still get some benefit from the greater precision of 16-bit mixing. As for the popularity of the SB16, here's what Wikipedia says:

The Sound Blaster 16 was hugely popular. Creative's audio revenue grew from US$40 million per year to nearly US$1 billion following the launch of the Sound Blaster 16 and related products.

So yeah, it was a popular and widely supported card, but underutilized during the first couple of years of its shelf life. Probably one of the reasons why a lot people stuck with the SBPro. Another could be that third-party manufacturers were offering SBPro compatibility on their sound cards, but rarely did the same for the SB16. Therefore SBPro = potentially wider user base.

Stereo sound was a major feature. The advantages of CD quality mixing were relatively smaller, considering the sample quality was limited by storage capacity at the time.

firage wrote on 2020-09-22, 11:25:

Stereo sound was a major feature. The advantages of CD quality mixing were relatively smaller, considering the sample quality was limited by storage capacity at the time.

This was my thinking as well but considering games in the 486 era (1992 onward) were fairly common to be on 4+ floppies and to require hard disk installs, was it more an issue of storage capacity or development cost?

appiah4 wrote on 2020-09-22, 11:39:

was it more an issue of storage capacity or development cost?

Storage capacity.
Development costs would be the same, selecting "16-bit" in audio recording software isn't any more expensive than selecting "8-bit".

There is also the matter of cpu power.

Several games had a sound quality selection
1 pentium
2 486
3 386
4 386sx

On my Cyrix dx2 I usually selected pentium class 16bit stereo sound, all that would happen was an occasional screen studder
The lowest settings were usually 8bit mono 11khz for 386

I guess many game manufacturers were still targeting 8-bit audio as the largest common denominator, as well as to save disk space, as others already mentioned.

Had the SB16 been downwards compatible with the Pro, a lot of DOS games would probably not have bothered with adding explicit support for the former (just to enable stereo support), and would simply have offered a "Sound Blaster Pro or Sound Blaster 16" option, not unlike how a lot of 16-color games showed "EGA/VGA" as a single option in their setup progams.

An additional possible explanation for Sound Blaster Pro having been "the game standard" for so long may also have been the fact that many sound cards from Creative's competitors (notably Windows Sound System compatible cards) included compatibility with the Sound blaster Pro, but not with the Sound Blaster 16.

In reality, yes it it the common denominator. Because Mono versus Stereo can be added by adding few bits. But moving from 8bit to 16bit, is total rework.

digger wrote on 2020-09-22, 12:13:

I guess many game manufacturers were still targeting 8-bit audio as the largest common denominator, as well as to save disk space, as others already mentioned.

Had the SB16 been downwards compatible with the Pro, a lot of DOS games would probably not have bothered with adding explicit support for the former (just to enable stereo support), and would simply have offered a "Sound Blaster Pro or Sound Blaster 16" option, not unlike how a lot of 16-color games showed "EGA/VGA" as a single option in their setup progams.

An additional possible explanation for Sound Blaster Pro having been "the game standard" for so long may also have been the fact that many sound cards from Creative's competitors (notably Windows Sound System compatible cards) included compatibility with the Sound blaster Pro, but not with the Sound Blaster 16.

Yep. In general commercial software writers are pragmatic: aim for the widest possible footprint. Prior to SBPro2, very few people had a sound card of any description, so given the big success of SBPro2 and its clones, they very quickly dominated the market. SB16 came into a market already full of SBPro2 and clones - and was broadly compatible with it too (we complain about stereo muddling, but back in the day few were so fussy), so by covering SBPro2 you could get vast majority of peoples' cards covered, where SB16 would at best service a sizeable minority.

I doubt the Mobygames figures actually, I have the feeling a lot of "SB16" games are "SBPro/SB16" games with no specific SB16 code just using SBPro2 spec and ignoring stereo problems.

I agree with other people that Soundblaster Pro support was so prevalent not because actual Creative Soundblaster Pro cards were so prevalent, but rather because many popular competing cards and clones emulated the Soundblaster Pro. Hardcore gamers might have spent the extra on a genuine Soundblaster Pro or 16 to ensure compatibility, but an average family PC would have had a clone card which only supported the Pro. Plus, normal people just had OPL3 synth then, which sounds kind of dirty and a good match to 8 bit audio -- piped through tiny, tinny speakers that came with the PC or sound/CD-ROM upgrade bundle. Having sound other than the PC speaker was a huge deal at the time, high fidelity or otherwise.

I agree with points in posts above.

Also I think it was a matter of serendipitous timing for the SBPro. The desktop PC market was really burgeoning in the early 90's, hand-in-hand with the explosion of related marketing. You couldn't spend 30 seconds paging through computer magazines of the day without being facialed by a bright colorful Creative advertisement.

The SBPro really hit the spot, at the time. The feature set was just right. Adlib compatible, we all knew what that was. Stereo, well we all knew what that was, and why it was desirable. Sound effects *at all* was a really new thing to PC gaming at the time, so the divide between PC Speaker -> Sound Blaster Of Any Kind At All, was perceived to be a million times greater than SBPro(2) -> SB16. "Greatly diminishing returns", in essence.

Another key to keep in mind is the quality of speakers used on virtually all PC's of the time. If they were barbeques, you'd have trouble tasting which animal the meat came from, you know...

Cuz all SB16s suck balls pretty much.

kolderman wrote on 2020-09-22, 23:29:

Cuz all SB16s suck balls pretty much.

My CT2230 w/ rev CT1703-A DAC disagree with you.

Probably one of the quietest and most trouble free Sound Blaster cards iv used. Midi stuttering is a non issue if your primarily into FM.

As for the whole SBPRO deal. Honestly. I don't think it every truly got support for its full features until mid/early late 90s when games like Duke 3D came out.

Even if your game did support SB16 at its fullest early on, You'd probably be loosing performance trying to push out the high bitrate audio anyway. Why bother.

Shreddoc wrote on 2020-09-22, 23:23:

Another key to keep in mind is the quality of speakers used on virtually all PC's of the time. If they were barbeques, you'd have trouble tasting which animal the meat came from, you know...

Heh, true.. but my Panasonic stereo that I used 3-way speakers with that had 12" woofers back in the 90's was pretty sweet. Nothing like having my speakers blasting behind me while I was playing Duke3D, Wing Commander, etc. and having my Mom tell me to turn it down and responding that I can't hear what she said because it is too loud. 😁

Pretty sure that stereo and those speakers were hers when she was a teen.. Either that or they were my Aunt's.

SodaSuccubus wrote on 2020-09-23, 02:16:

kolderman wrote on 2020-09-22, 23:29:

Cuz all SB16s suck balls pretty much.

My CT2230 w/ rev CT1703-A DAC disagree with you.

Probably one of the quietest and most trouble free Sound Blaster cards iv used. Midi stuttering is a non issue if your primarily into FM.

If you're primarily into FM, SB16 digital audio is also a non-issue 😉

That said, we can be fussy about all the SB16 bugs - back in the day 99% of users didn't give a damn and/or had no experience of how it was without bugs, which is why the cards sold so well.

As for the whole SBPRO deal. Honestly. I don't think it every truly got support for its full features until mid/early late 90s when games like Duke 3D came out.

Even if your game did support SB16 at its fullest early on, You'd probably be loosing performance trying to push out the high bitrate audio anyway. Why bother.

Not all games are FPS, but indeed, most early games aiming for quality audio did MIDI and left you to figure out how to synthesize it.

Sound Blaster Pro: Why is it the game standard?

At first, we have two version SB Pro: SB Pro old (OPL2), SB Pro 2 (OPL3)

Also, have changes (between this version) into DSP (PCM playback). I can't find this topic into documentation 🙁 In short words - Pro 2 can play minimal enough quality. Quality - i am talk about increased PCM frequency (not about output - all SB has very noisy output)

Why SB Pro 2 become as a standard? All later cards from Creative had the same OPL3 (excluding AWE series), differences into DSP is minor (between SB Pro 2 and SB16). Huge count of SB Pro 2 (cheapest) clones, but a few clone SB16 (I am not sure, may be "none" or near it). For example, in 90's, I can buy $15-$30 SB Pro 2 clone (like ESS).

why was SB16 compatibility adoption so slow

From programmers point of view: it is have no sense, minor count of new features (for games). So, as game-dev, - for me will be enough sb pro2.

PS: In 90's, i am never had own card from Creative, because it has a price the same as ticket to Mars, for me.

DosWorld wrote on 2020-09-23, 17:57:

[...]

Why SB Pro 2 become as a standard? All later cards from Creative had the same OPL3 (excluding AWE series), differences into DSP is minor (between SB Pro 2 and SB16). Huge count of SB Pro 2 (cheapest) clones, but a few clone SB16 (I am not sure, may be "none" or near it).

There were a few, but they were late and low-end - or rather: they were invariably used on cheap low-end cards. Avance Logic ALS-007 and -100, and C-Media CMI-8329 and -8330 are the best examples. ALS-100+ and -120 had some SB16 features, but lacked high DMA, which undermined the compatibility.

For example, in 90's, I can buy $15-$30 SB Pro 2 clone (like ESS).

Yep, it's just like with the PC and DOS itself - they were far from the best design. even back in 1981. Having a big brand back up the PC helped a bit, but the real reason PC and DOS beat just about every other platform was the clones - a real IBM was too expensive for most, but with hundreds of (mostly cheaper) alternatives, the software ecosystem was huge. Same with Sound Blaster.