David Clark ANC Headset Question

RFazio · #1 12-18-2010, 04:16 PM

My buddy has one of these David Clark ANC headsets and I wanted to try them out. My friend has not used them much as they don't really work in his ultralight like plane and I was thinking of buying them from him. Anyway I plugged them into my RV and took a flight with another buddy. He was using my regular David Clarks. The ANCs sounded good but very low. I had to up the volume on my intercom a lot and then my friends headset was too loud. Then when I tried to transmit I was getting a loud sqeel in my ears. My friend heard it also. I couldn't get it to stop when transmitting. It was like feedback from an open mike near a speaker. I played with the volumes on the radio and intercom. I had to switch headsets with my friend because I couldn't transmit. Anyone have any ideas what I was doing wrong? Someone said you shouldn't mix different types of headsets, especially the ANC ones. I think something could be wrong with them. I don't know?

ColoCardinal · #2 12-18-2010, 04:41 PM

We have a D-C X-11 ANC and a LightSpeed Zulu ANC working thru a PM1000 intercom in our Cardinal and they play together just fine. We also have an older Peltor (egg), D-C H10-14.3, and an in the ear LightSpeed M1 (all, non-ANC). We've used about every combination possible without issue. I've used almost all of these in my buddy's Piper Arrow thru a PM2000 intercom without a problem. Sometimes there's a volume difference but it's always been possible to sove by changing the combination with the volume knobs on the headset, intercom and radio. The squeal sounds like a problem unrelated to using other headsets with this one. Did it transmit okay from the passenger position? If there's a problem with the D-C, they'll most assuredly fix it for free. In fact both Lightspeed and Peltor offer the same excellent level of service from my experience.
FWIW, the D-C X-11 is my favorite and the Zulu is my wife's!

RFazio · #3 12-18-2010, 06:55 PM

Yes, both transmitted thought the squeel was not nice to hear. I don't know if other aircraft heard it but I assume they did, since we both heard it in our headsets. I'm using a PS engineering 5000 audio panel as my intercom, and an icom 210 radio.

CPSONE · #4 12-18-2010, 08:20 PM

You can use any passive headset with a dynamic mic and it will be fully compatible with the fixed wing GA models of David Clark ENC's.
What is the model number of the DC's. You can read it from the top of the headband. (If you're curious about year and month of manufacture you can look under the mic boom side ear seal and there is a date stamp on the face of the earcup).
Take the mic sock (foamy) off and ready the Mic model number. It should say M-7 or M7A. If it doesn't you might have a military impedance headset there which might account for the difference in volume. (presuming you turned the volume up on the knobs on both sides.
Check the stereo-mono switch on the com cords junction where they split into separate cords. Make sure it's on Mono for a mono intercom and stereo for if you have a stereo intercom.
If it's a battery powered headset make sure all the batteries are in correctly, they cam with 9V battery packs and originally a mit full of AA's battery packs.
I had an employee working for me (for a short time) that put some batteries in backwards and a customer tried them on and flipped the switch. You could hear the squeal from 10 feet away...
The squeal could be from a speaker like you said. If you have an audio speaker in your airplane, your side tone when you speak would be audible and would loop through your mic and cause the squeel. (You probably checked this already but worth mentioning.).

Check the model number of the headset, that may shed some light on your problems. It should be a H10-13X or XL or X11 if battery powered. If it says H10-76XL or XP it's a low impedance (military) headset and that's your problem.
Hope this helps.

lella · #5 12-19-2010, 10:28 AM

I have a modified ANR kit set of David Clark's.
I have also noted an occassional (but God-awful squeel). My squeel was steady and not just when transmitting. It seemed to stop when I shut the ANR battery off and restarted it.

CPSONE · #6 12-19-2010, 11:41 AM

Sqeals and other funny noised sometimes happen when your wearing sunglasses with fat arms that interfere with the seal of the headset earseals around your ears.

RFazio · #7 12-19-2010, 01:18 PM

I am checking the model number. My friend s going to call me with it. He is a 45 minute drive from me. These were doing it only on transmit, and I made sure to have a good seal between the cups and my head. I did have a hat on and took it off. No difference. I do get a sqeel sometimes if I have two headsets plugged in and I'm only using one. The other set will feedback through the open mike. So I'll unplug the unused set. That was not the case this time, as there were two of us in the plane.

hudgin · #8 12-19-2010, 04:41 PM

I converted a DC set to ANR with a kit I got. The instructions said that to put the mike on one side only of your head. I don't remember which side that is but when it squeals I put the mike on the other side. The squeal goes away. The volume level on this set is as good as the Light speed set I have.