A kind of microphone

[Rex Allers]

This is way off from the normal physics of the heart of the forum, but gonna post as I think I recall that you (Doug) are a musician and have done audio electronics and software.

So a while ago I was TV surfing and on PBS I came to...
"Woodsongs Old Time Radio Hour"
from:
Lyric Theater and Cultural Arts Center
Lexington, Kentucky

They have a youtube channel here: http://www.youtube.com/user/WoodsongsOTRH
(and the newer ones use the mics to follow.)

A bit better than the normal normal crap on TV. So I'm watching the musical performers and then am thinking, "what are those microphones they are using?" Never seen the like. Looks like they were made in the garage but they must be good to be used here. I almost posted something here then to see if anyone knew of them.

But I did a lot of web searching and over a while eventually figured out that this is what they are:
http://www.eartrumpetlabs.com

Here's a pic of the main version "Edwina" from their pages

So on their pages they have lots of videos of various artists using them and some liking them a lot.

For me any opinion on the mics is theoretical.[*] My hearing sucks. But a decade or two back I got some not terrible mics and had some notion about the technology.

So I assume these are large diaphragm cartridge condenser mics. Clearly they (eartrumpetlabs) make their own mounting hardware or adapt plumbing pieces to make the supporting structure. I didn't find any statement of making their own cartridges or if they are buying them from some other vendor.

So I don't know if they really are good or are just attracting those who like the funky look.

Any thoughts from anyone?


[*] I had the privilege of doing a walking tour of Vietnam in 1968. I could have had a card that read "Have Gun Will Travel". At a recent reunion of guys I served with I asked, "Who's got ringing in their ears", (tinnitus) everyone raised their hands. My high frequency hearing has been gone for many years.

[Doug Coulter]

Hadn't heard of these guys specifically. Round and open both sides probably does mean electrostat, but could be a couple of other alternatives. The pic of their shop didn't give much away....
I have tinnitus too sometimes, but one can drown it out - and it's additive, not a nonlinear convolution, so you learn to "hear around it". I've lost a little bit of the high end, but was lucky not to lose more; pretty much all shooting/HE I've done I had protection for, and why that Marshall amp stack I played drums in front of for years didn't kill my hearing, I have no idea. We quickly learned how to make it loud "out there" while keeping it down onstage - it was handy to be able to communicate during a performance...directional main PA systems are your friend!

I didn't hear any horrible badness on that YT channel, but then, even on a decent system here, you're kind of limited by the sending end bitrate compression and processing.

Large thin diaphragms are easy to make sound good it seems, at least for some value of good and especially if you don't mind the bidirectional pattern - other patterns are a lot harder to get right. Turns out it's not that hard to make a membrane that has less effective mass than the boundary layer of air on both sides, so it follows pretty well, and so limp it doesn't support odd resonance modes either. Now, how you detect that motion...up for grabs. Lots of ways work.

There's a local guy here who makes the mics they use on NPR, they did a feature on him a few years back, and we briefly got in touch as at the time I had the big vacuum system set up to do coatings, and would have been able to crank out good diaphragms. We didn't get together on that, though, and now I forget the name...there are a lot of little isolated pockets around here of various interest groups, the mountains kinda act like asylum walls (but aren't padded).

[johnf]

I would guess condensor microphones
they are good for almost DC to 50kHz with little or no distortion and do not overload easily
available from your usual suspects like alibaba and banggood.
https://www.banggood.com/Professional-S ... rehouse=CN
units a favored by good recording studios although many artists like their "own" type

[Bob Reite]

I don't know about "doesn't overload easily". Maybe the mic itself doesn't but the electronics afterwards do. Give me a good dynamic mike like an ElectroVoice RE-20 for voice work.

[Doug Coulter]

Heh...I have 2 RE-20's and two PL-20s here, and yup...but like always, "it depends". If I had a breathy female I'd use some condenser perhaps (unless she's also an air-shredding power singer with extreme dynamics) . The PLs are so numb...you can't overload one or the following electronics unless you try very hard, and the noise floor of the preamp is usually the issue (I used them for bass and other drums too...or a Marshall stack).

But yes, in radio station use, the PL sound is where all those liquid mellifluous voices come from. Nothing compares. Most preamps need an impedance stepup xfrmr to get the noise down.

You can guess what's in daily use, though...

The Neumanns come in the nicest box...the Yeti is the best per buck at least for good pattern(s) for video chats and recording acoustic guitar. It's a switchable pattern dual condenser, USB interface built in.

[Doug Coulter]

I'd add that other things often are more important than the mic used...
In this example, I'd say the artist and the room acoustics are the big deal...my little teac portastudio is probably better than that Zoom setup, but who cares?
https://www.youtube.com/watch?v=7UwA8zvDcho


From the cheapo portastudio (little condensers) - starts placed on a rock in a babbling brook, ends on a hillside with barking deer (and various things that were edited out later for use in sound efx).
http://www.coultersmithing.com/data/Fou ... TSAT01.WAV

Storm recorded with the 20's (and one of my more-vocal cats and other glitches)
http://www.coultersmithing.com/data/FoundSound/ST0.WAV

Of course, one has to recognize that there is a huge difference in sound production vs reproduction...in the former, "is it pleasing" is more important than "is it accurate" by a long shot.
I like natural sounds for accuracy. In my audiophool days one test we did was to record a quarter being dropped on the floor of the studio, then play it back later for some unsuspecting victim, mixed in behind what they were ostensibly listening to. If they looked at the right spot on the floor, we knew we were getting it right. Ditto getting people to go out and roll up car windows on a sunny day in summer when thunder was mixed under the music...(helps to have seriously good response in your speakers...).

[Doug Coulter]

To add:
Looks ain't everything. We consulted for a hearing aid and prosthetic business that needed to find a good mic that had good time response for pitch tracking DSP software, and generally sounded good.
The customer collaborated by building a big test stand out in the open with a spark-gap and capacitor as a source for a step function - as well as an overload test when another sine wave was also present. Mics were hung 30' off the ground on a wire between two phone poles. We were able to get good impulse response samples before any reflections off the ground and so on. A poor man's anechoic chamber - actually better than most of the commercial ones for this use.

The winner might surprise you - a radio shack 3-wire condenser just blew off all other contenders by a mile. The two wire ones,,, not so much (overload). Fancy expensive ones, nope. The newer silicon sensors, nope. This little $3 cartridge was better than all by a lot. The only one an FFT of the impulse was flat, and I mean flat - phase was flat too. Matshushita (panasonic to you).
Put it in a fancy package and it'd beat almost all commercial mics for pure sound (in an omni). Their other mics, not so much, their attempts at cardiods or noise cancelers were a pretty mixed bag.

The fancy packaging reminds me somewhat of the line about fishing lures - at least half of the appearance is designed to attract fishermen, not fish.

I laugh when I see a PL 20 all hung up in a rubber spider and with a huge blast shield in front...they don't pop unless hit with an air compressor front on, anyone with the least mic discipline never has an issue with a bare one - on a boom stand if they need other clearance. Just vocalize across the front and you're fine even if you do p-pop because you never learned how to use your lips to direct the air away from the mic (doh). Ditto a number of other microphones. The box usually isn't most of what makes it work, though there is that function in the 20's - the cartridge is near the back, and there are some interesting other materials in there to make them flatter...EV did a big paper on their tricks for that - and their ESP-9 headphones.

Which, if you were brave enough (they weren't cheap) the 20's were great for live PA use, as they were so flat you could get a lot more gain before feedback in most situations, and the back null in the pattern was very useful.

[Bob Reite]

Ah yes, We knew that we had my system so real when we thought that Ed's wife was applauding the performance from the hall, when in reality the applause was on the recording (an "audiofool" 15 IPS CCIR EQ reel to reel tape) that we were playing.

We did a voice mike "shoot out" a few years back pitting various mikes against a $5000 (in 1985 dollars) Neuman against mikes in the $400 price class. The winner of that contest for the best accuracy was the Shure SM 81 condenser mike. It did tend to get hit with plosives when not talked "across" instead of "into" but the optional big outdoor wind screen solved that.

[Doug Coulter]

At some point they all have their "sound". My dad had a CD at one point where the same setup (some gazebo band) was recorded with all the high dollar mics, and you could compare the sounds. None were really perfect, but all were so darn close it came down to what you liked emphasized a little bit.
Not impossible to plosive a '20, but I don't have that problem if it's me - when you're recording other "talent' well...but it still makes me laugh when people put them on these elaborate suspensions, and then tie wrap the XLR cable to the boom a couple inches from the plug. I mean...what's the point if you're going to do that? I mean, try not to hit the darn thing!

BTW, recording that storm with the 20s..I used a couple toboggan caps for wind/rain guards. Kind of pleasantly surprised how well that worked - and they stayed dry.

Maybe my hearing is shot, but that Blue Yeti is actually pretty good. Maybe not at the limits of what can be done, but man, per dollar - and as someone who grew up around microphones people would trade precious metals and diamonds for - and who even built my own ribbons - they're surely not bad. Again, the user...lots of people seem to think the pattern emits from the end...nope, it's the front.
Mine gets a lot of compliments in video chats and music jams just sitting on the table about half a meter or so away. It probably doesn't hurt that this room doesn't have a parallel ceiling and so on, the acoustics are pretty good (on purpose, I worked on that in the design before putting the sticks together). At any rate, easily the equal of a pair of $400 mics from a decade ago - for $100 (and it's stereo if you want). That curve of price/performance over time is like the one for computers back in the day.

The imaging is really good too - I have one behind the fusor setup so left is the back of the tank and right is the front, and from the remote setup I can audibly tell where any noise in the room comes from. In that case, I'm using the zero-latency analog output in the mic base sent back over a couple twisted pairs to an amp-speaker set in the operator console. Handy...you never know when some data's going to be what you were missing.

[Rex Allers]

I just thought I would mention a bit more detail on the EarTrumpetLabs stuff that I brought up at the beginning.

They defiantly are condenser mics. If you dig, each version has a spec pdf like this one:
https://static1.squarespace.com/static/ ... Edwina.pdf

Which says: condenser, large (26 mm) diaphragm

In all the looking I did I never saw any hint regarding the actual cartridges/capsules as to whether they make them or buy from some other vendor. My guess would be the latter, but maybe they do it all. More control on the product and long term consistency if they do.

They mention some differences between models. They have some electronics. No Idea how much of differences are physical vs electronics.

Just thought I'd throw that into the discussion. I have no intention to buy/try one. As I mentioned, my hearing makes most of this moot for me.