Scratch track for camera

[Derek H]

What is the purpose of the components? Filtering unwanted RF from affecting the receiver?

[Johnny Karlsson]

Well, the headphones / cable is also the antenna...

[Izen Ears]

Inductors!  Haha! I only understand their principles, I haven't gotten to them in my extremely slow paced self learning.  Thank you!

I still don't get what those inductors and capacitors do.

 

Dan Izen

[LarryF]

I'm guessing here but if the headphone cable is also the antenna, then the inductors block RF but pass audio and the capacitors pass RF but block audio.

LF

[SonicBoomPole]

As I understand it, the inductors are for RF filtering and the cap is for DC/Audio filtering. Yes, the cable is also the antenna...

 

The wiring makes sense when you think about it. A balanced mono output (like on your mixer) is the same signal out of phase (Hot/Cold, +/-) plus ground, 3 connections. Pretty basic stuff.

 

The Comtek uses a balanced mono output. Simple. It is NOT a standard HP output.

 

Headphone wiring is STEREO not Mono with the Tip=Left, Ring=Right and Sleeve being a common ground for both mono signals. Totally different. This is why standard stereo HP don't work with an older PR-72b Comtek rx and they require mono wiring to get sound into both ears. Newer PR-75a/PR-216 models went to a different output wiring scheme that employs out of phase mono on a "stereo" TRS connector that is compatible with HP that use stereo wiring.

 

So for the purpose of sending audio to a mono input, be it a camera or a mixer or maybe a speaker you have to understand what the input wants before you select the correctly wired cable. 

 

If you are sending to a balanced mono input you can either use a balanced or unbalanced cable. Balanced would probably be better. If you are sending to a stereo input (as on a DSLR perhaps) then you need to use an unbalanced cable. Think of a camera with a stereo input like stereo HP, the signal will cancel out. If you want to be safe and cover all your bases while having the least amount of cables just use unbalanced...

 

As mentioned previously:

 

Balanced      Tip=XLRp2, Ring=XLRp3 and Sleeve=XLRp1

Unbalanced Tip=XLRp2, Ring=XLRp1 and Sleeve=XLRp1

 

As someone here used to say - it depends and call the manufacturer for the info you seek

 

[EnotsMedia]

This is what I LOVE about JWSOUND…a simple question becomes a deep dive into the why/ how / what. Things I didn’t give much thought to suddenly become an interest and knowledge is absorbed. Good stuff. 

[Allen Cavedo]

On 5/7/2023 at 10:44 AM, SonicBoomPole said:

As I understand it, the inductors are for RF filtering and the cap is for DC/Audio filtering. Yes, the cable is also the antenna...

 

The wiring makes sense when you think about it. A balanced mono output (like on your mixer) is the same signal out of phase (Hot/Cold, +/-) plus ground, 3 connections. Pretty basic stuff.

 

The Comtek uses a balanced mono output. Simple. It is NOT a standard HP output.

 

Headphone wiring is STEREO not Mono with the Tip=Left, Ring=Right and Sleeve being a common ground for both mono signals. Totally different. This is why standard Stereo HP don't work with a Comtek and they require mono wiring.

 

So for the purpose of sending audio to a mono input, be it a camera or a mixer or maybe a speaker you have to understand what the input wants before you select the correctly wired cable. 

 

If you are sending to a balanced mono input you can either use a balanced or unbalanced cable. Balanced would probably be better. If you are sending to a stereo input (as on a DSLR perhaps) then you need to use an unbalanced cable. Think of a camera with a stereo input like stereo HP, the signal will cancel out. If you want to be safe and cover all your bases while having the least amount of cables just use unbalanced...

 

As mentioned previously:

 

Balanced      Tip=XLRp2, Ring=XLRp3 and Sleeve=XLRp1

Unbalanced Tip=XLRp2, Ring=XLRp1 and Sleeve=XLRp1

 

As someone here used to say - it depends and call the manufacturer for the info you seek

Good info except for one thing, I use standard stereo wired headphones from JVC and Sony all the time with my Comtek receivers and they work just fine. Sometimes clients use their own HP or a Apple EarPods and they all work providing mono sound in both ears. 

[Patrick Farrell]

2 hours ago, Allen Cavedo said:

Good info except for one thing, I use standard stereo wired headphones from JVC and Sony all the time with my Comtek receivers and they work just fine. Sometimes clients use their own HP or a Apple EarPods and they all work providing mono sound in both ears. 

It works, only the left and right ears are reversed polarity. If I listen on a comtek it drives me nuts but most producer types don't notice.

[SonicBoomPole]

19 hours ago, Allen Cavedo said:

Good info except for one thing, I use standard stereo wired headphones from JVC and Sony all the time with my Comtek receivers and they work just fine. Sometimes clients use their own HP or a Apple EarPods and they all work providing mono sound in both ears. 

The brain between your HP is smart enough to discern a mono audio signal is present even though it is out of phase. The electronic circuitry of camera or mixer inputs isn't as intuitive and will cancel out of phase mono signals on the same input. When I see people using Apple ear pods they're generally only using it as a mono single ear solution because they prefer not wearing over the ear HP or old crumbly ear foam or awkward single ear solution offered by the usual suspects.