Neumann KM85 mic mods?

[TimS]

Hi All,
I've just landed a pair of 1970's Neumann KM85s and after doing a bit of online reading & research, have come to the conclusion that these are basically a KM84 with a built-in bass rolloff.

What I'm wondering is, are there any mods that can be done to these mics that can restore the bass frequency responses to more like its predecessor (84)?

The freq curve is almost exact until the roll off at 300Hz.. and then it rolls off quite steeply.
I've attached a pic below so you can see the curves of both mics in mention. These are from the original user manuals of the KM 83/84/85 & KMS 84.
Any ideas or suggestions are appreciated..
Tim..

[Jason]

Damn!!!

Are these the 2 km85's that were on ebay a week or so back???


I tried to contact the seller after the auction because I missed the end. Never got a reply. Would have loved a pair of these.

Cheers

Jason

[TimS]

No Jason,
These were from a private sale I was lucky to find.
Tim..

[davemc]

Pretty sure no or not easy.. I had 4 at one stage and checked around. Doing some quick google searches now
http://recforums.prosoundweb.com/index.php/m/170734/0/
http://www.3daudioinc.com/3db/showthread.php?t=909

They are really nice mics you just do not get the low end with them. For a lot of applications you might use them on you might roll off a little anyway.

[TimS]

Pretty sure no or not easy.. I had 4 at one stage and checked around. Doing some quick google searches now
http://recforums.prosoundweb.com/index.php/m/170734/0/
http://www.3daudioinc.com/3db/showthread.php?t=909

They are really nice mics you just do not get the low end with them. For a lot of applications you might use them on you might roll off a little anyway.

Great links davemc - thank you. I had not been to those forums - worth the visit..
I am only thinking about doing this, otherwise it is probably just too expensive or not worth it (i.e risky to mic)
These mics are in original condition and barely exposed to any high SPL. They have been boxed for 20yrs and never used in that time.
Picking them up on Sunday.
Can't wait.
Tim..

[rick]

its not feasable , its a different capsule, not necessary either .
for anything you use them for that km 84 are good at you will not notice the rolloff

[TimS]

Thanks for the replies guys.
After more reading and replies, they will stay original.
Look forward to throwing them in front of Pete's sweet Taylor for a testdrive!! :-)
Tim..

[adamcal]

don't worry about the rolloff, I love km85's, use them all the time, hi hats, overheads, close ride, under snare, very close acoustic guitar all places where I would rolloff the bass anyway, even more than the mic does.