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Sonus Faber. Don't worry, the manual is in English.

Martin Logan—excellent advice on not only the product, but setting it up and using it in a real world environment.

Has to be Manley Labs, it's actually worth reading.

Vandersteen

Manley Labs. Who else?

That honor goes to my Fostex F-12. As a musician, I record much of my own music "off the cuff," so I have used the F-12 more times than I can count. The owners' manual is among the best I've come across, covering everything from recording to overdubbing to playback and all points in between. There are wonderful schematics, as well. Cudos to Fostex.

ZVOX

Good as some manuals are, I've never run across one that answers most of the important questions I might have. Speaker manuals, for instance, should have complete impedance/phase angle graphs. Amp manuals should be more specific than referring to 4 or 8 ohm speakers, since we all know that one speaker manufacturer's 4 ohms is another's 8, and average ratings are less than informative if a speaker, say, goes below 2 ohms in the bass. A welcome inclusion would be suggestions on proven pairings with particular accessories like footers and wires.

Pass labs. Simple informative and amusing.

That would have to be Ray Steven's "1,836 Seconds of Humor."

McIntosh

McIntosh, hands down. Of all the different brands I have owned, nothing compares to a well written and detailed McIntosh manual.

They all seem to make cheap manuals that aren't very clear.

My McIntosh owner's manual is quite nice. But I haven't seen very many, so how would I know?

Audio Research

I've had much gear in the past 30+ years. I would have to say that the best manuals I ever received were from Pass Labs. I can't really say that Pass is the best, perio, just the best I've seen. Rega was just about the worst, but I think the expectation is that the dealer is supposed to be your reference source.

I don't know who's would be best but I do know that a few manufacturers do provide their manuals on-line for anyone anywhere, on any product they made. Harman Kardon and Adcom provide thier customers with necessary PDF documentation on all of their product lines. Way to go!

Musical Fidelity, Magnepan, and my Lehmann Black Cube all came with good manuals. They were not especially large, but they were informative. Some manufacturers need to get someone with some writing skills to recompose their manuals, however. Some are written in gobbledegook.

Jeff Rowand Model 5. Apogee original Full Range Ribbons

Moscode by far. They were hilarious!

Linn manuals are pretty good. They even provide them for speakers!

ReVox

The best (most usable info) manual I have received was provided by REL.

Mark Levinson always provides a very thorough manual with a great cover. If you're a minimalist, Rowland is the way to go since they don't provide a manual at all, at least not for the two components I've purchased.

S.M.E.

When I worked at Sony and Proton in the '80s, I wrote many of the equipment instruction manuals... so I can say with some degree of irony and chagrin that I am responsible for many of those millions of VCRs helplessly binking "12:00! ... 12:00! ... 12:00! ..."

Most important to me are the manufacturers who offer manuals on their website to download as a PDF file. Since I live in China, the manuals I get are written in Mandarin and therefore of no use to me. Most of "the big boys" already offer this but not all (Jeff Rowland, Naim, Sonus faber... pitty.) However, the one manufacturer that takes this one step further by offering manuals in four different languages, is Linn.

Yamaha, Thorens, SME.

Bryston. Primare has good manuals also.

Parasound's manuals have detailed graphics on "how to" and additional tech information about the product and the segment of the product. The Focal-JM Labs speakers manuals also have very detailed instructions about how to place speakers, including mathematics formulas.