CM-i3 Audio Headset

I have no experience with the CM-i3, but I see by the specs, it's a cardioid. A cardioid mic is directional, but is not considered "noise cancelling." A cardioid has one null in its pickup pattern but can still pick up sound from most other directions. Most handheld vocal microphones, such as an SM58, are cardioids.

A noise cancelling mic is much different. They are a two port device that only picks up sources that are close to one port compared to the other. They are very effective in noisy places, but have the downside of being picky about placement. The mic has be right in front of your lips, or your voice will get cancelled along with everything else.
 
I have no experience with the CM-i3, but I see by the specs, it's a cardioid. A cardioid mic is directional, but is not considered "noise cancelling." A cardioid has one null in its pickup pattern but can still pick up sound from most other directions. Most handheld vocal microphones, such as an SM58, are cardioids.

A noise cancelling mic is much different. They are a two port device that only picks up sources that are closer to one port compared to the other. They are very effective in noisy places, but have the downside of being picky about placement. The mic has to be right in front of your lips, or your voice will get cancelled along with everything else.
Thank you @FMEng for 'breaking the ice' on this one. @John Palmer and yourself are harkening back to what is / was a legendary micing technique first brought to the forefront of arena rock concerts by the Grateful Dead with their ground breaking "Wall of Sound" touring system in which each vocal mic was two identically matched capsules mounted adjacent to each other but with their outputs connected in 'series opposing' rather than 'series aiding'. Please forgive my sketchy / hasty, lacking in detail explanation and failure to fully support my assertions with properly documented references. If you saw / heard / remembered any of their tour's stops along the way, you couldn't help but be impressed by their audacity to flaunt the rules of physics and standard operating practices by having the gall to put themselves and their vocal mics directly IN FRONT of their towering main stacks and stand there playing, singing, and shifting your hearing threshold WITHOUT a trace of feedback. You're definitely correct (as usual) @FMEng in your post and I'm sure @John Palmer is paying rapt attention along with joining me in thanking you for your post. I'm CERTAIN 10 seconds of Googling "Grateful Dead / Wall of Sound" will unearth more than you ever wanted to know about the pioneering micing techniques employed on their tour. Similar canceling techniques were employed by the military for tank, field, artillery, bomber and helicopter inter-communications applications, although with greater emphasis on intelligibility than pleasingly natural fidelity.
Thanks again.
EDIT 1;
Link: https://en.wikipedia.org/wiki/Wall_of_Sound_(Grateful_Dead)
EDIT 2; Quote from link: The Wall of Sound acted as its own monitor system, and it was therefore assembled behind the band so the members could hear exactly what their audience was hearing. Because of this, Stanley and Alembic designed a special microphone system to prevent feedback. This placed matched pairs of condenser microphones spaced 60 mm apart and run out of phase. The vocalist sang into the top microphone, and the lower mic picked up whatever other sound was present in the stage environment. The signals were added together using a differential summing amp so that the sound common to both mics (the sound from the Wall) was canceled, and only the vocals were amplified.
Toodleoo!
Ron Hebbard
 
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I’ve not tested the PS headset myself, but their gear is top notch designed and built. There are some interesting testimonial videos on this product on their website. If I was in the market, I’d be inclined to give it a try. If you have portable intercom base station or WL, maybe you could try one at a distributor ?
 
Has anyone used the Point Source CM-i3 in the years since this thread first appeared?

I've been using either the Clear Com CC-110 or the Pro Intercom SMH-710. Light weight, single ear headsets. They are both fine, but I would love to find something lighter and even more comfortable. The PS CM-i3 is intriguing alternative. Or does anyone have any other ideas?
 
Has anyone used the Point Source CM-i3 in the years since this thread first appeared?

I've been using either the Clear Com CC-110 or the Pro Intercom SMH-710. Light weight, single ear headsets. They are both fine, but I would love to find something lighter and even more comfortable. The PS CM-i3 is intriguing alternative. Or does anyone have any other ideas?
I treasured my Clear Com CC26 Ultra light single ear; it was definitely for personal use and would NEVER stand up in rentals or schools.
SeasonsBest &
Toodleoo!
Ron Hebbard
 
I'm a big fan of my Telex PH-88.
 
I treasured my Clear Com CC26 Ultra light single ear; it was definitely for personal use and would NEVER stand up in rentals or schools.
SeasonsBest &
Toodleoo!
Ron Hebbard
Yeah I'm thinking about buying something for myself not the kids.
 
But to pick up an earlier aside: Yeah, for *com* you want a dual-opening noise cancelling headset.

If you want it to be an on-air mic, then you want a cardioid or super pattern instead, but that will have *much* different ambient noise handling characteristics.

Next to impossible to get both noise-cancellation and good frequency response in the same mic housing.
In ye olden daze ( Thank you @TimMc ) of (up to) 12 Kw (Harmonic laden) SCR dimmers and telco style single conductor patch cords, speaking on your headset while mid-performance re-patching used to be a, fraught with coms buzz laden, problem in need of a solution.

One solution that worked was to glue a second, identical, dynamic mic element on the outside of your Beyer DT108 or 109 headset and connect it in series opposing with the mic you were speaking into. Both mics were operating in essentially the same acoustic and electro-magnetic hum laden space thus the mic you weren't speaking into canceled the output of its mate. Worked well; looked DUMB, but worked dandy. Not bad for mid seventies (19 NOT 18) technology.
Season's Best & Toodleoo!
Ron Hebbard
 
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I seem to remember hearing, Ron, that some current day mics for that kind of service have a second coil, isolated from the moving magnet, which does that electromagnetic hum cancellation. Don't have a citation, though.
 
I seem to remember hearing, Ron, that some current day mics for that kind of service have a second coil, isolated from the moving magnet, which does that electromagnetic hum cancellation. Don't have a citation, though.
The Beyer DT108 or 109 trick cancelled air-born as well as electro-magnetic hum; looked really silly, worked extremely well.
Toodleoo!
Ron Hebbard
 
I too have a Telex PH88 and I think it's my 3rd or 4th one. I love how comfortable it is and how slim it is. Great for A2 and not be completely shut off from the headset side and also followspot where you're trying to listen for lyrics as well as calls.
It's underlying issue, which is why I have to replace it every couple of years is the T shaped metal piece from the headband that fits into the earpiece that allows it to swivel.
The earpiece is thin plastic and after a few months, the earpiece will will start separating at the seam and then the slot where the T from the headband enters will start cracking. If you catch it when it just starts to split, you can get some epoxy in there, I try to not split it on my own just to try and extend the life.
Even after you've glued it in, because the plastic is so thin, you can only re-glue it so many times before there just isn't enough plastic to glue together and you end up gluing the T shape into the earpiece, preventing it from swiveling anymore.
 
So, sounds like I need to try out a PH 88.

I'm still really intrigued by the wrap around headset and earbud style of the point source or the ClearCom CC27
 
Myself, I'm concerned that they describe it as a com headset, but *call it* an "audio headset"... which it is... incredibly not.

Why not both?

I've deployed, but not personally used the CM-i3 in two different capacities. The first way I've put it out on shows is as an intercom headset for some rather picky Deck SM's who seemed to enjoy this model a lot. The second way I've put it out on shows is as an audio headset with combined IEM. On a lot of shows I end up putting the MD in a DPA 4065 for talkback mic and IEM's and the two-in-one saved some ugly arts and crafts on a DPA Halo for a few MD's who don't like having to put on 2 different pieces of equipment, but do enjoy wearing a single piece of equipment.
 
Why not both?

I've deployed, but not personally used the CM-i3 in two different capacities. The first way I've put it out on shows is as an intercom headset for some rather picky Deck SM's who seemed to enjoy this model a lot. The second way I've put it out on shows is as an audio headset with combined IEM. On a lot of shows I end up putting the MD in a DPA 4065 for talkback mic and IEM's and the two-in-one saved some ugly arts and crafts on a DPA Halo for a few MD's who don't like having to put on 2 different pieces of equipment, but do enjoy wearing a single piece of equipment.
I don't know what I was on about, but I'm goin with "that was 3 whole years ago!" :)

In fact, I said it backwards; it's clear it's an *audio* headset, hard pressed to hook up to Com, not the other way around.

See my other thread about doing both in one headset... :)
 

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