Jump to content

Schoeps CMIT 5U Trouble


Thijs Stam

Recommended Posts

So i got this old CMIT 5u which worked like pristine a couple days ago. i always store the mic in my closet in a dry groom with normal temperature.

Today when i started shooting the mic gave almost no sound and alot of self noise. i couldn't use it for the whole day. last time this happened was at a night shoot but every worked back when i layed it in a dry room for a while but now it doesn't work at al and is simply unusable. Even after a full day of drying there is no change and the mic still does the same noise and low sound problem. Have any of you guys got any tips or had the same problem. I'm thinking of contacting schoepst for a cleaning and check up but i have no idea how they are with older CMITS. thanks infant for the tips. (the mic was bought second hand from a trusted seller and everything worked when tested)

 

Thijs,

Link to comment
Share on other sites

On 9/29/2019 at 9:01 PM, Thijs Stam said:

I'm thinking of contacting schoepst for a cleaning and check up but i have no idea how they are with older CMITs


What do you mean? The entire CMIT range isn’t old at all, by Schoeps standards

 

3 hours ago, Ontariosound said:

Like Scotch and cigars.  Sennheiser MKH are ready when you are.


they also sound like too many cigars

Link to comment
Share on other sites

The only groom dry enough to play host to a cmit would be a mummy, and those aren’t easy to come bye. I wonder if your issue isn’t moisture but maybe phantom power. 

 

We can’t really help diagnose your problem without more details. What are you plugging it into? Not all mic pre amps provide full 48V. Could you have your mixer set to 12V PH?

 

However if moisture is the culprit, you either live in a tropical region, or your groom has an humidifier on in the closet. That would prove convenient for his cigars. 

Link to comment
Share on other sites

20 minutes ago, RadoStefanov said:

Speaking of schoeps repair takes way too long! Can they train somebody from redding to repair them? It is so expansive to send the mics back to Germany each time. I have many many mics but some people can not afford to not have their mic away for a long time. My 2 cents. 

 

I have been to the factory and received some training. However, capsule issues cannot be handled anywhere else but the factory which has dedicated purpose built rigs for testing (they were built decades ago) which Schoeps cannot sell to anyone. 

 

I have done some repairs here in India and do have a set of spares etc. However, the humidity issue is something related to dust on the diaphragm as well which is very difficult to clean and only the factory can do it. 

 

-vin

Link to comment
Share on other sites

45 minutes ago, soundtrane said:

 

I have been to the factory and received some training. However, capsule issues cannot be handled anywhere else but the factory which has dedicated purpose built rigs for testing (they were built decades ago) which Schoeps cannot sell to anyone. 

 

I have done some repairs here in India and do have a set of spares etc. However, the humidity issue is something related to dust on the diaphragm as well which is very difficult to clean and only the factory can do it. 

 

-vin

Thanks for the great answer Vin

That makes sense. 

Link to comment
Share on other sites

all mics need cleaning sometimes. i sent a ccm41 in for service and it took about a month portal to portal. i did have to pick up an replacement to fill in those gaps however

the cmit that i have i got at the same time and i haven't had any issues with it. i live in a humid climate and always rock solid. i store mine in a vark audio dry tube. works like a charm.

Link to comment
Share on other sites

Thijs

Like mentioned - check phantom power - we had an issue with Wisycom plug on not supplying enough for the current that the Cmit required (think it was 5.5 mA) - Everything worked well after we added a Mozegear phantom power supply (although that came apart with connectors tht are just glued to the box with hot glue -not well made)

Link to comment
Share on other sites

On 10/1/2019 at 7:54 AM, JonG said:

The only groom dry enough to play host to a cmit would be a mummy, and those aren’t easy to come bye. I wonder if your issue isn’t moisture but maybe phantom power. 

 

We can’t really help diagnose your problem without more details. What are you plugging it into? Not all mic pre amps provide full 48V. Could you have your mixer set to 12V PH?

 

However if moisture is the culprit, you either live in a tropical region, or your groom has an humidifier on in the closet. That would prove convenient for his cigars. 

 

Sorry for the late response. My mic is plugged in to a zoom F8 48V phantom power. It was only when filming in the moist conditions back at home after an hour of leaving the mic on the table the mic worked perfectly again without problem. with the same phantom power and recording settings. 

 

On 10/9/2019 at 5:16 AM, ivanovich said:

all mics need cleaning sometimes. i sent a ccm41 in for service and it took about a month portal to portal. i did have to pick up an replacement to fill in those gaps however

the cmit that i have i got at the same time and i haven't had any issues with it. i live in a humid climate and always rock solid. i store mine in a vark audio dry tube. works like a charm.

After you take it out of the dry tube do you directly plug it in or let it sit for a while in the moist conditions?

On 10/7/2019 at 6:14 AM, soundtrane said:

 

I have been to the factory and received some training. However, capsule issues cannot be handled anywhere else but the factory which has dedicated purpose built rigs for testing (they were built decades ago) which Schoeps cannot sell to anyone. 

 

I have done some repairs here in India and do have a set of spares etc. However, the humidity issue is something related to dust on the diaphragm as well which is very difficult to clean and only the factory can do it. 

 

-vin

Very useful information vin! I will be sending my schleps teethe factory either way of what happens on this forum. but this is all very useful information for me to learn about mics since I'm just a 19 year old beginner.

On 10/5/2019 at 8:56 AM, jdutaillis said:

I had a little trouble with my CMIT once and turned out one of the screws was loose and causing a weird grounding issue. Try tightening everything.

Screws are all solid on the mic and nothing is moving around. still a useful tip and thanks for telling me!

Thanks for all the responses! im new to this forum and still learning a lot abut sound everyday. im 19 year old and from the Netherlands and signing up to this forum has been a lot of help. thanks for all he support and its nice to have professionals responding to my problems. 

On 10/9/2019 at 10:15 AM, Stef Albertyn said:

Thijs

Like mentioned - check phantom power - we had an issue with Wisycom plug on not supplying enough for the current that the Cmit required (think it was 5.5 mA) - Everything worked well after we added a Mozegear phantom power supply (although that came apart with connectors tht are just glued to the box with hot glue -not well made)

I tested the mic after the day of recording and it had no troubles and worked perfectly. so sadly it was not the power. the zoom f8 hasn't got the greatest preamps so that's the next thing i will be upgrading.

Link to comment
Share on other sites

49 minutes ago, Thijs Stam said:

im 19 year old and from the Netherlands


I think from within the EU you will find the turn-around with Schoeps to be much quicker, simply because the shipping is quicker and easier. They have improved their service times substantially. Earlier this year they repaired my SuperCMIT. From the day they received it to the day they told me it was ready, they needed 8 days. So including shipping the mic was gone for less than 2 weeks. And they offered a loaner in the meantime...

Link to comment
Share on other sites

6 hours ago, Thijs Stam said:

After you take it out of the dry tube do you directly plug it in or let it sit for a while in the moist conditions?

 

When I get to location I try to always get the mics up on the booms asap and continue setting up the rest of the gear, cameras and such. By the time all is said and done, I plug in the the battery for the boom TX’s and everything is acclimated. It normally doesnt take too long unless theres a huge temperature change in which case lenses need to acclimate too....

Link to comment
Share on other sites

  • 1 month later...

when I encountered issues with CMIT and humidity - it was when the mics were out on an overnight shoot and the temp was dropping and we reached the dew point. You could see dew on the pelican cases. The CMIT was not putting out any audio. It may have needed a day or two to dry out. having a few MKH options would be very wise as the design of these mics are completely different if interested look up 'an MKH story' PDF. On the other hand your MKH mics may go berserk in the presence of a cell repeater or hotspot as they are RF oscillating microphones. So both have their sensitivities but you can go back and forth when you run into problems with one or the other....

 

Link to comment
Share on other sites

from the PDF- 

 

https://assets.sennheiser.com/global-downloads/file/11061/MKH-Story_WhitePaper_en.pdf

 

“How does RF microphone technology work? The principle is simple: Sound
waves deflect the diaphragm of the condenser capsule and change the
capacitance between the diaphragm and the nearby back electrode
(backplate). Contrary to the more common low frequency (AF condenser) method, the capacitance variations are not converted directly into audio signals but modulate a high-frequency (radio-frequency) signal generated by an oscillator inside the microphone. This signal is then immediately demodulated inside the microphone, thus recreating the audio signal but with a very low source impedance that is well-suited for driving a transistor amplifier. Thus an RF condenser microphone is basically comprised of a transmitter and receiver that are directly wired together. The RF signal is therefore kept inside the microphone; only the audio signal is supplied to its output, just like all other microphones”

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...