R/E/P Community

Please login or register.

Login with username, password and session length
Advanced search  

News:


Author Topic: U87 dropped, stopped working  (Read 7736 times)

Offline Winterland

  • Newbie
  • *
  • Posts: 12
U87 dropped, stopped working
« on: September 14, 2009, 02:28:43 pm »
Unfortunately one of our engineers dropped one of our vintage U87's. We have a pair of very early ones close in serial number. They both work and sound great, until now.  

The grill was dented slightly. It hit his leg then a carpet.
It does not pass any sound. I took it apart and can not see any obvious broken parts, loose wires etc.

Any suggestions of any type of troubleshooting we can do?

Where is a good place to get it checked out and fixed without having to wait 6 months?

Thanks Todd


Todd Fitzgerald
Producer/Engineer
 
Winterland Studios
Minneapolis, MN
www.winterlandstudios.com

Offline radiovinheta

  • Full Member
  • ***
  • Posts: 156
Re: U87 dropped, stopped working
« Reply #1 on: September 14, 2009, 02:46:04 pm »
Take a look inside of mic, and make some pics to post here.
U87 is easy to desassembly.

Sorry about my poor English... i'm from Brazil.

Offline mwurfl

  • Jr. Member
  • **
  • Posts: 64
Re: U87 dropped, stopped working
« Reply #2 on: September 14, 2009, 03:39:04 pm »
You might check the power source selection switch to see if perhaps it got knocked into the battery power position.  In any case it might be worth trying to switch it back and forth a couple of times, then leaving it in the desired position (which I'm assuming is for phantom power).  It's possible that the switch's internal contacts might have been on the verge of not connecting well, and switching it back and forth a couple of times might restore the connection.

Good luck!

Mark W
"Not everything that counts can be counted, and not everything that can be counted, counts."

-- Albert Einstein

Offline Martin Kantola

  • Sr. Member
  • ****
  • Posts: 362
Re: U87 dropped, stopped working
« Reply #3 on: September 14, 2009, 04:10:30 pm »
First thing I would suspect are the connections from the main board down to the connector assembly. If the body was twisted in the fall they might have broken, not necessarily easy to see, but had a pair of U87s for repair recently and they both had issues in this part. Seems the rods that support the main board are not rigid enough. Also the capsule is a heavy piece of brass to drop, have you checked that it's still in place?

Martin

Offline jpaul_bordon

  • Jr. Member
  • **
  • Posts: 71
Re: U87 dropped, stopped working
« Reply #4 on: September 14, 2009, 05:36:44 pm »
Was it powered up while being dropped? That might help diagnosis.

Offline radiovinheta

  • Full Member
  • ***
  • Posts: 156
Re: U87 dropped, stopped working
« Reply #5 on: September 14, 2009, 06:09:52 pm »
Connect the mic on a pre-amp, turn Phantom Power on.
Vintage U87 have a "meter" , that you can see if is correct powered... you can se in the hole in the body.

Offline Klaus Heyne

  • Hero Member
  • *****
  • Posts: 3154
Re: U87 dropped, stopped working
« Reply #6 on: September 14, 2009, 08:07:01 pm »
The mic amp on U87 is pretty robust. One or several of the wires connected to the capsule may be torn.

Self-serve is a great first attempt at repairing a condenser mic. It is an empowering boost to one's self-worth. But it has its limits (look at the many different suggestions you already have received- from head to toe of the mic!)

So, if at first you don't succeed, I'd recommend to try again, and then, to give some of those starving condenser mic techs a reason to live!
Klaus Heyne
German Masterworks
www.GermanMasterworks.com

Offline rodabod

  • Sr. Member
  • ****
  • Posts: 353
Re: U87 dropped, stopped working
« Reply #7 on: September 14, 2009, 08:24:33 pm »
Depending on how dented the grill is, check it isn't touching any part of the capsule.
Roddy Bell

Offline Winterland

  • Newbie
  • *
  • Posts: 12
Re: U87 dropped, stopped working
« Reply #8 on: September 14, 2009, 10:29:45 pm »
Thanks for all the suggestions. I will try all asap. You guys are great.

FYI This U87 has the old style mount that has the cable built in so I did swap with our working one to rule out the mic cable being broke somewhere. It was not the cable/mount. It worked with our other U87.  

I am not sure if the mic had phantom on when dropped. Will find out.
The dent is slight so the capsule was not touching anything. As I said I took it all apart, head assembly also and there is no visible problems.
I will look for the specific spots now that I have something to look for.

I am curious about the phantom switch. Can't remember if I tried that already. That would be an easy fix.

Thanks Todd  
Todd Fitzgerald
Producer/Engineer
 
Winterland Studios
Minneapolis, MN
www.winterlandstudios.com

Offline seedyunderbelly.com

  • Hero Member
  • *****
  • Posts: 2465
Re: U87 dropped, stopped working
« Reply #9 on: September 15, 2009, 01:12:50 pm »
Great idea from Klaus to check open the head assembly and check the connections..  If that does not work call the guy I emailed you about  -j

Offline MI

  • Hero Member
  • *****
  • Posts: 1292
Re: U87 dropped, stopped working
« Reply #10 on: September 15, 2009, 02:24:40 pm »
Does it have the battery pack?

Is it possible S1 got knocked into battery position?

Mario


Offline MI

  • Hero Member
  • *****
  • Posts: 1292
Re: U87 dropped, stopped working
« Reply #11 on: September 15, 2009, 02:40:38 pm »
index.php/fa/13331/0/

Offline Michael Brebes

  • Sr. Member
  • ****
  • Posts: 253
Re: U87 dropped, stopped working
« Reply #12 on: September 15, 2009, 03:58:30 pm »
Since you have two of the same type, another quick test is to pop off the head assembly and swap between the two mics.  That will tell you quickly whether it is wiring in the head or the body.

Offline Schallfeldnebel

  • Hero Member
  • *****
  • Posts: 816
Re: U87 dropped, stopped working
« Reply #13 on: September 15, 2009, 05:23:47 pm »
jpaul_bordon wrote on Tue, 15 September 2009 05:36

Was it powered up while being dropped? That might help diagnosis.


I can imagine when a microphone is powered up, hitting the floor hard, the FET stage might be blown up, maybe this has happened.

Schallfeldnebel
Bill Mueller:"Only very recently, has the availability of cheap consumer based gear popularized the concept of a rank amateur as an audio engineer. Unfortunately, this has also degraded the reputation of the audio engineer to the lowest level in its history. A sad thing indeed for those of us professionals."

Offline Winterland

  • Newbie
  • *
  • Posts: 12
Re: U87 dropped, stopped working
« Reply #14 on: September 21, 2010, 08:16:26 pm »
I am very late to this but I did fix the mic myself and has been working fine.
There was a broken solder connection. I have a picture I took and am looking for it to post here.

Todd Fitzgerald
Producer/Engineer
 
Winterland Studios
Minneapolis, MN
www.winterlandstudios.com