Can I play any Quake 1 mods without original game?

I've found quite a lot "mods" on http://quaddicted.com, and I've tried some open-source Quake engines (QuakeSpasm, DirectQ), but they all seem to complain in this way or other, that I haven't got the original game contents.

Is it possible to play any quality, free content with some of the free Quake 1 engines, without the original game?

EDIT:
Trying to clarify: initially, I was left with an impression that some of the mods are actually "total conversions" (e.g. from Quoth description: "The intention is to provide quality custom content for Q1 mappers and players in a single pak file."), but now from the partial answers below, I'm starting to believe that it's not so, and they all (?) still expect some of the original Quake contents present?

That said, my overall intent in the question remains the same, but I'll try to reformulate it in other words, then. So:

Is there any:

• free, quality (although that's subjective, so can be skipped), full replacement ("total conversion"?) of contents for Quake 1 engine, fully independent from original paks/wads;
• plus a free engine for running it, that won't try to detect & complain that I don't have "a registered version of Quake 1"?

As a runner-up question, could I somehow (and if yes, then how?) detect the full list of missing assets for some given mod, and maybe try to then build some substitutes by myself, to complete the picture?

Thanks!

Solution 1:

Is it possible to play any quality, free content with some of the free Quake 1 engines, without the original game?

Quake epsilon includes the first quarter (original shareware portion) of the game, but other than that, no.

Solution 2:

It Depends(TM), but the general answer is no.

Quake handles game assets in a manner similar to an "overlay" filesystem. The .pak files contain a directory tree of files (similar to ZIP files). Quake mods typically contain only updated/additional map geometry, textures, and monster logic, with the remaining textures and logic being furnished by the original .pak files. The search order is generally (from my ageing memory):

• Files in the actual filesystem,
• PAK files named on the command line,
• pakN.pak files in the ID1 directory, searched in reverse alphanumeric order (e.g pak1.pak gets searched before pak0.pak).

Some "total conversion" mods might work, since they purport to replace all the original Quake assets. But you'd have to actually try it to find out.