Warning: Creating default object from empty value in /homepages/11/d132647312/htdocs/Amfone/mkportal/include/SMF/smf_out.php on line 47
New microphone




 
The AM Forum
April 16, 2021, 11:26:04 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: New microphone  (Read 7874 times)
0 Members and 1 Guest are viewing this topic.
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« on: January 07, 2010, 03:23:16 PM »

In trying to set up the flex for the best sound, I tested my Audio Technica 3035 mic into the flex with no processing, just mic into the radio (through the ultra voice 3000) with nothing turned on, and it sounded dull and muffled in the monitor.

So I thought maybe a better mic was in order, and I looked at the RE20, looked at the reviews, and found a comparison to the Heil PR40.
The two sounded very close on the wave files, with the PR40 sounding a little better to me.

Anyway, I bought a PR40, and compairing it to the AT 3035, its very close from what I can tell.
The 3035 has a lot more output. Both sound dull to me, but I think I need to record both and play them back to get a good idea of what they really sound like.

Anyone using a PR40?

Brett


And why is it that audio sounds so different in the monitor, say between different settings, or mic's, or even radios, and the people at the other end say the difference is very subtle?



Logged
KL7OF
Member

Offline Offline

Posts: 2207



« Reply #1 on: January 07, 2010, 04:47:53 PM »

There are a lot of receiver considerations when getting audio reports from other stations...
Logged
W2XR
Contributing
Member
*
Offline Offline

Posts: 888



« Reply #2 on: January 07, 2010, 05:42:13 PM »

In trying to set up the flex for the best sound, I tested my Audio Technica 3035 mic into the flex with no processing, just mic into the radio (through the ultra voice 3000) with nothing turned on, and it sounded dull and muffled in the monitor.

So I thought maybe a better mic was in order, and I looked at the RE20, looked at the reviews, and found a comparison to the Heil PR40.
The two sounded very close on the wave files, with the PR40 sounding a little better to me.

Anyway, I bought a PR40, and compairing it to the AT 3035, its very close from what I can tell.
The 3035 has a lot more output. Both sound dull to me, but I think I need to record both and play them back to get a good idea of what they really sound like.

Anyone using a PR40?

Brett


And why is it that audio sounds so different in the monitor, say between different settings, or mic's, or even radios, and the people at the other end say the difference is very subtle?





Hi Brett,

Perhaps a little EQ boost is in order here. Maybe something on the order of 6 to 8 dB of boost around that portion of the audio spectrum where "presence" occurs. I think most AM rigs, even when capable of true hi-fidelity transmission, do tend to sound somewhat dull (particularly in the other guys receiver) unless EQ is properly applied.

Remember too, that you have to boost beyond the point where the audio response sounds good to you in your off-air monitor. After our signals take a trip through the other guy's receiver, a lot of that so-called "brightness" (an overworked adjective for audio if there ever was one) is lost. A good treatise on this topic was written by Bob Orban, father of the Optimod audio processors for broadcast applications. Go to the Orban website to download the white paper he had written on this subject. The NRSC pre-emphasis curve utilized by all AM broadcasters in the US was an attempt to mitigate the brightness roll-off that is characteristic of most AM receivers. The boost at 9 khz is something on the order of around 9.5 dB, with the turn-over point beginning around 1 khz as I recall.

In short, I think you really have to equalize for the entire link or system, if you will: i.e., the microphone, the transmitter, and compensate for the inherent high-frequency roll-off in the other station's receiver to get the best overall or pleasing received audio. Not an easy task; especially when considering the significant variables in the receiver-side of things.

I have used both the EV RE-20 and the RE-27, and I sold off the RE-20 about 3 years ago. To my ears, the RE-27 is a much better sounding microphone for AM applications, and it is my all-time favorite for AM usage. It has more midrange presence and clarity vs. the RE-20. I also have an Audio Technica ATM-31; this is a broadcast-grade condenser microphone I have had for about 25 years. It has a very warm, full sound, but not the same level of presence as the RE-27.

I also have two RCA ribbon microphones; a 77-D and a 44-BX. Ultra-cool looking classic microphones, but in my opinion, neither of them sound particularly good for AM; they both exhibit that Bing Crosby "syrupy sound", which probably made them great for recording 78 RPM records. This syrupy sound cannot really be corrected via equalization.

And I do boost the heck out of the midrange and high-frequencies in my rig.

73,

Bruce
Logged

Real transmitters are homebrewed with a ratchet wrench, and you have to stand up to tune them!

Arthur C. Clarke's Third Law: "Any sufficiently advanced technology is indistinguishable from magic".
KC4VWU
Member

Offline Offline

Posts: 664


« Reply #3 on: January 07, 2010, 05:46:09 PM »

Grant, W4BVT, had used both on the air once in an A-B comparison. The PR-40 didn't sound like it had as much lower end response; but it was so little difference you'd really have to listen well to discern it. I think he runs balanced line all the way through to the tx. and he did note that it makes a big difference.

Phil
Logged
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« Reply #4 on: January 07, 2010, 06:00:08 PM »

Listening in the audio output of the symetrix audio amp, both mics sound real close to me.
The Heil pr40 picks up more hum as the level has to be turned up much more than the 3035.
The hum might be from the cable, which runs along with the ptt cables.

Both mic's seem to have plenty of lows.

I need to get a good eq setup. The ultra voice is a nice all in one audio box, but it does not have a lot of eq abilities.
 
In my book, the Audio Technica 3035 is better than the PR40, which is supposed to be in the ballpark with the re20.

If you can do phantom power, it might pay to check out the 3035, it (used to be) much cheaper than the pr40 or the re20...

Brett
Logged
W2XR
Contributing
Member
*
Offline Offline

Posts: 888



« Reply #5 on: January 07, 2010, 06:10:26 PM »

Listening in the audio output of the symetrix audio amp, both mics sound real close to me.
The Heil pr40 picks up more hum as the level has to be turned up much more than the 3035.
The hum might be from the cable, which runs along with the ptt cables.

Both mic's seem to have plenty of lows.
I need to get a good eq setup. The ultra voice is a nice all in one audio box, but it does not have a lot of eq abilities.
 
In my book, the Audio Technica 3035 is better than the PR40, which is supposed to be in the ballpark with the re20.

If you can do phantom power, it might pay to check out the 3035, it (used to be) much cheaper than the pr40 or the re20...

Brett


Yeah, but if dull sound is your problem, plenty of lows are not the issue. You need a microphone with plenty of highs and presence!!!! I would seriously try and seek out a good, used RE-27 and a good parametric or graphic EQ and your problem should be completely solved. You can't necessarily EQ a dull-sounding microphone to make it sound bright; you need to start first with a proper microphone for the task at hand.

73,

Bruce
Logged

Real transmitters are homebrewed with a ratchet wrench, and you have to stand up to tune them!

Arthur C. Clarke's Third Law: "Any sufficiently advanced technology is indistinguishable from magic".
WA3VJB
Guest
« Reply #6 on: January 07, 2010, 06:39:54 PM »

Brett, I have a "loaner" Sennheiser MD-421 that I suggest you try before you spend significant coin. I would be glad to send it to you for the price of insured shipping.

Google it for the basic rundown.

I used it for years as my primary mic, and continue to use it as a 2nd op mic when Pam or anyone else is on the air alongside me.

Attributes: 

-- LOTS of output, so your pre-amp does not have to work as hard. Keeping the input amp gain as low as possible reduces hum as well as circuit noise.

-- NICE kick-up in the upper mid range area, which helps with clarity. The high end response is crisp without being harsh or "brassy."

-- ROLLOFF switch, five positions, that allows you to reduce bass / low end response to minimize a tubby or muddy sound and best match to your voice tonal qualities.

-- POPULAR  with vocalists and recording studios worldwide the past 40 years since it hit the market, so price discounts are plentiful and unit-to-unit quality is reliably high.

Downsides:

-- POPs the percussive voice sounds without a windscreen if you close-talk

-- Some handling noise if your mic stand is on something making mechanical sounds (fingers drumming, blowers blowing, iron a-humming, etc.)


Let me know your interest.


Logged
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« Reply #7 on: January 07, 2010, 07:00:20 PM »

Paul,
Thanks for the offer, but I think I have some experiments to do first.

What I want to do is transmit at low power into the dummy load, tune a receiver up with about a 6kc filter, and record the audio for playback.
That way I can try adjusting things for a good sound at the distant end.

I think I am doing it all wrong right now, by trying to get it to sound good in the mod monitor.
My hearing does not help, I cant hear a thing above 3100 Hz!

Brett




Logged
Bill, KD0HG
Moderator
Member

Offline Offline

Posts: 2563

304-TH - Workin' it


« Reply #8 on: January 07, 2010, 10:20:21 PM »

I also use a Sennheiser 421 here. Like Paul says, there's goodly response adjustments on the mic itself. Also, very directional, which helps with room acoustics and things like mod transformer feedback. Really, the 421s are a terrific all-purpose broadcast mic.

The only better dynamics I like are the Shure SM-5 or SM-7. You can do a presence boost and/or low cut on the SM-7, but, hey, I don't transmit 50 HZ either..Mod tranny doesn't like it...

Another nice thing about the 421 is proximity effect enhancing the bottom end..You can close-talk the thing and sound like God..
Logged
K5UJ
Contributing
Member
*
Offline Offline

Posts: 2845



WWW
« Reply #9 on: January 08, 2010, 12:10:58 AM »

when it comes to mics you'll get a lot of opinions and I don't mean that in any negative sense, but there are a lot of mics out there.   I don't like condensers because they are so darned sensitive and need all sorts of pop screens and so on.   If you don't handle one right, you can wind up txing a lot of background noise and breath blasts on the mic.

With dynamics (I assume you are only interested in low Z mics) you can do pretty well with the good old Shure SM58.   Put a foam pop sock on it and set it up.  I used to bemoan the fact that my voice isn't one of those deep announcer baritone voices, then after I got into AM I was glad.  I don't want to hit peak modulation with lows.  I want my meager sideband power to be in the mids and highs where the speech intelligence is.  IOW, if Bob's PR40 picks up low end, it might be a good idea to roll it off with an equalizer (or something).   I know the RE20 and 27 are great mics but for ham use they are pretty pricey and I've listened to A/B with the PR40 and RE20 too, and I would not have known a mic was getting swapped out if I had not been told to listen so they are pretty close. 

Rob
Logged

"Not taking crap or giving it is a pretty good lifestyle."--Frank
WA3VJB
Guest
« Reply #10 on: January 08, 2010, 05:31:34 AM »


I think I am doing it all wrong right now, by trying to get it to sound good in the mod monitor. My hearing does not help, I cant hear a thing above 3100 Hz!

Brett

Advice --

You mention recording and playback, but just to be clear:

Please do NOT try to listen and adjust in real time. You will drive yourself crazy and it won't be accurate.  Sound waves bounce around inside your head while you're talking, affecting how you perceive your own voice.

Make a sound file or a tape recording of your voice and play that source through your system while adjusting. Probably what you intend, but not sure from your wording.
Logged
W3RSW
Contributing
Member
*
Offline Offline

Posts: 3290


Rick & "Roosevelt"


« Reply #11 on: January 08, 2010, 07:52:26 AM »

Right Paul,
Last thing you want is to be set up using the finest sound bone conduction can yield..   Grin

I like the idea mentioned on another thread of using the remote receivers with their delay in hearing what you sound like, complete with phase delay and other neat distance effects.
Logged

RICK  *W3RSW*
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« Reply #12 on: January 08, 2010, 08:53:10 AM »

Yes, I think that is part of my problem (if I have one). I need to simulate a receiver and record, not listen to the monitor.

Remote receivers need one to actualy transmit over the air, and I would rather use the flex to rx my signal from the 813 rig into the dummy load, record that in the 6kc position, then adjust things after listening to the recored audio.
The flex allows direct recording and playback with the click of a button...

I also need an EQ.
The flex has a 10 band eq built in, but it seems (to me) to not cut or boost all that much, and the other rigs dont have anything other then the vx2000 which is very limited in the eq department.
I think I will pick up a dual 15 band eq for $100.00, and use one pre, and one post the vx2000 so I can EQ and chop off the highs below 5000 Hz.

Doing the mic comparison between the 3035 and the pr-40, they ARE very close, I doubt anyone at the dist end could tell the difference between them. The 3035 has a LOT more output, and is rf imune, does not seem to have any problems with poping or wind noise, and comes with a nice shock mount for about $150.00.
The PR-40 has a lot more proximity effect, and the vx2000 input gain is almost all the way up.

I replaced the long balanced mic cable with a shorter one last nite and got rid of the hum in the pr-40.

When I was in the store buying the pr-40, I checked out the Heil gizmo that allows you to hear all the mic's, and there was a big difference between them all, the heritage did not sound bad, less low end, and I almost got that, but I already have a very nice sure 55s...($10.00 fest buy) which looks the same.

Brett





 
Logged
W1GFH
Guest
« Reply #13 on: January 08, 2010, 12:09:52 PM »

There's nothing wrong with your mic. Most high quality mics run with no EQ will sound perfectly natural on a receiver set to a 20KC bandwidth. But since 6-12KC is the norm for your listeners, you need to apply a bunch of of EQ pre-emphasis around 2500Hz, or you will get reports of sounding "muffled". The D-104 is the exception, having a natural 2-3K boost built into it.
Logged
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« Reply #14 on: January 08, 2010, 01:01:38 PM »

I went to the local music store and picked up a DBX dual 31 band eq, model 231.
Normaly, I would not have wanted a 31 band, but it has the ability to cut at 3.15, 4, 5, 6.3 or 8 Khz.
The 15 band units had bigger jumps, something like 5 or 8 or 10KHz.

I figure cut above 5KHz with a clear band, and cut 5 when its crowded, or even 4KHz, that would give about 4.5 KHz audio with a fast roll off.

I guess, boost a lot between 1 to 3.1 KHz and add in some 40 to 100 Hz boost....

Brett

Logged
WA3VJB
Guest
« Reply #15 on: January 08, 2010, 02:06:59 PM »

The mic demonstration gizmo was out at Dayton one year, and it would have been interesting to drop a phase inverter in the line that they had feeding the RE-20.  You may already know that Pin 2 is "hot" and Pin 3 is "not." 

But Brett, yes, you need all the scruff that's caused by real propagation and receiver characteristics for someone trying to listen to your signal.  

Otherwise it's just a clinical run and not reality.

These internet streaming audio receivers aren't bad for that purpose, since they have a set of problems to create a good test for the clarity and tonal characteristics you wish to achieve.

Before they came around, I was among the people happy to simply make a recording of a station off the diode of the R-390(A) or SP600, varying the selectivity, and then rendering the recording as an uncompressed "wav" file to email to the station wanting an aircheck.  I would suggest certain EQ settings, and the recording would continue with such adjustments. It then is up to the recipient to determine where it sounds best.



Logged
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« Reply #16 on: January 08, 2010, 03:16:04 PM »

The gizmo at hro had a headset with a phaze switch on the side of it....

Brett
Logged
KC2IFR
Guest
« Reply #17 on: January 08, 2010, 03:28:06 PM »

2 things u have to understand when using a mic.
1: make sure the input Z of the device satisfies what the mic is intended for...trying to drive a high Z input with a low Z mic will always sound thin.
2: then we get into the balanced or unbalanced question. The RE20 is a balanced low Z mic.....so u have to make sure its wired correctly. If your input is unbalanced, make sure the crossover connection is correct.  Balanced is ALWAYS better in  high RF field's.   
Logged
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« Reply #18 on: January 08, 2010, 03:32:15 PM »

Both the 3035 and the pr40 are balanced using xlr connectors, so is the vx2000.
I just wonder why the pr40 has to be turned all the way up to get any audio out of the pr40....
The pr40 says its 600 ohms.

Brett
Logged
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« Reply #19 on: January 08, 2010, 11:21:03 PM »

Hooked the dbx eq up, after much cable making, cabinet moving, etc, and found its a piece of crap!
As soon as I slide it into the cabinet with the other audio stuff, I get a high noise/hum, induced right into the eq.

Its got a metal case, but I dont think they do anything with grounding the various pieces, and it picks up the power supply fields from the other equipment.
I got it reduced by separating the stuff, the eq is in the bottom of the cabinet with a wide space between it and the other stuff at the top.
I thought dbx was a good brand, but I guess its not anymore.

Now there is no room for the homebrew RX and the place is a big mess...

Back to the drawing board...

Brett
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.087 seconds with 19 queries.