The main difference is in the internal electronics, the amp in the mic.. I personally think all mics are different. One U87 will sound different than the next. You have to look for the "good ones". As far as knock offs, same thing applies. But If you want a U87 sound, that's what you should shop for. BTW, the old U87 is supposed to sound better than the newer U87Ai...

Happen to lucky enough to have an old U87 and it works real good in a lot of different applications.
One thing I can say is it doesn't sound like any other mic I have.
As far as the knock off's FORGET IT.
It's sorta like an amp simulator, you think the knock off sounds real good untill you put it up against my vintage U87. At that point you hang your head and remember you get what you pay for.
Kurt I've never tried the (ai) verson I'd like to hear the difference someday.
Larry
Larry Howard

Larry, I couldn't agree more. All knock - offs have fallen short in one way or another. Our original U87s reign supreme above all others, even if the only thing that sets them apart is 'The Vibe'!

The ai has greater output.

None of these replies are correct about the model differences.

(Other than higher levels, though this is a complex result.)

You might as well go to my forum and get the facts while they're still there.

There is a thread on the subject.

Stephen, Does this mean I only get a B+ instead of an A? :D

Stephen, looked through your forum but no thread of that sort was found (I assume you were referring to "stephen paul audio"). would definatelylike to read that thread though...

The ai mics are basicly the Neumanns made after 1986. They are supposedly a little safer to operate as they have a lower impedance supply lead for the capsule polarizing voltages. They are about 10db louder and Neumann literature states that the signal noise ratio is improved by around 3db.

If you enter "U87 U87ai" (without quotation marks)
in the search field for Stephen's forum, you'll find this thread.

Only tried the U87ai on my voice, and actually prefer my Beyer M88TG instead.
Of course it wasn't one of Stephen's mod's...

Chris

It's probably because I don't know what I'm talking about...

After all, over 600 LSD trips... Ladies and Gentlemen, I must wonder...

Why am I qualified to say in any event, anything at all.

I actually recorded at Walley Heider Studios 3&4 wrecked on blotter or gel, some Red Dragon or something, and also at Elektra Studio A, (3M 2" 16 Track M56, with SM64 2 tracks, and a nice API with Quad installed, and I don't know...) and also at a whole bunch of other places on records you wouldn't believe the titles of! :D

Other than that, and my very eccentric, (yes, I know it, and yet, a lot of people out there, seem to really feel that what I have been doing, as I've bitten on the leg of this dog, now with Tony, and tried to sort of Frisbee and wrestle it, and make it go faster, and higher and more and more totality of designer control, so that there are less compromises in the design itself, due to the peculiar needs of directional mikes.

More independent controls so that impulse response and variables become more and more isolatable, so the design can be zero'd in on.

Kelly Johnson the guy who designed the SR71, and U2, had The Lockheed Skunk Works, I have the SPA Passing Windworks.

We'll see if it sticks. The Passing Windworks. The Black Op arm of SPA Inc. Hand me those beans.

I want one that's an honest plus six at 15k with sub micron film, and has an honest low-Q centered at 1k -26dB or better cardioid rejection, wide band as possible.

And a line level transformerless amp.

NOW we're talkin' 409. You know. 454 bored to 488 with a blower. Yes. Mother of Angels, just a Megawatt power supply. Instant total Power on fully damped tap.

Steve's roadside KiloWatt cafe.

Mmmm...

The Arizona desert stretches out to Four Corners and the Plains...

Tetonka... Buffalo.

Yeah, that was good stuff.

well, that certainly cleared THAT up! :D