My Dayton Omnimic isn't giving the same results as my other calibrated microphone running JustMLS (LspCAD) and I'm pretty sure it's the Omnimic that's not working properly.
I've tried everything the guys have suggested over at the partsexpress forum but it always displays a high frequency droop, but I get the impression that partsexpress think it's user error.
Before I send it back to the USA, I just wondered if anyone here in the UK has one that they could compare to mine? I'll happily send it to you and pay return postage. It just seems a waste sat in the cupboard doing nothing.
I've tried everything the guys have suggested over at the partsexpress forum but it always displays a high frequency droop, but I get the impression that partsexpress think it's user error.
Before I send it back to the USA, I just wondered if anyone here in the UK has one that they could compare to mine? I'll happily send it to you and pay return postage. It just seems a waste sat in the cupboard doing nothing.
Have you set the sample rate to 48kHz, stereo ("DVD quality")? I imagine they suggested that, but I thought I'd check just-in-case.
Another cause I've run into that can give a high frequency rolloff is that some CD/DVD players do that. If you're using one of the supposed "high end" CD players, they can easily do it -- they try to do things to "fix" an imagined digital problem and end up screwing up frequency response (no mfgr names given here - I don't want to deal with anyone's lawyers!).
Omnimic depends on the CD player and amp having flat response, which is easy for manufacturers do to. Unless they are trying to purposely alter the sound to appeal to some of the high end audiophile community.
Before sending the mic back, I'd try with a different CD player (preferably use a quite inexpensive player that makes no claims to any esoteric properties!) for the signal source. Or you can use the soundcard output of a computer or laptop to generate the test signal (though that requires cables and might result in ground-loop buzzing).
Another cause I've run into that can give a high frequency rolloff is that some CD/DVD players do that. If you're using one of the supposed "high end" CD players, they can easily do it -- they try to do things to "fix" an imagined digital problem and end up screwing up frequency response (no mfgr names given here - I don't want to deal with anyone's lawyers!).
Omnimic depends on the CD player and amp having flat response, which is easy for manufacturers do to. Unless they are trying to purposely alter the sound to appeal to some of the high end audiophile community.
Before sending the mic back, I'd try with a different CD player (preferably use a quite inexpensive player that makes no claims to any esoteric properties!) for the signal source. Or you can use the soundcard output of a computer or laptop to generate the test signal (though that requires cables and might result in ground-loop buzzing).
Note for Bill Waslo...
Bill-
I've been using your IMP/M for the past 20 or so years, have been very happy with it. Recently picked up an Omnimic and really like just plugging it into my music server for testing.
Once again, thanks for a great product!
Mike Barney
Bill-
I've been using your IMP/M for the past 20 or so years, have been very happy with it. Recently picked up an Omnimic and really like just plugging it into my music server for testing.
Once again, thanks for a great product!
Mike Barney
Help needed, please !
I normally use Clio in my "lab", but my version it is not very portable.
So I purchased Omnimic V2 a while ago, and now finally got ready for actually using it.
All the matching with the software and the mic. cal. code went well, and I have a spectrum on my screen with a live curve bouncing with noise in the room.
The mic. is obviously "hot".
But I do not succeed in making a sine-sweep response (or anything else) when I "press" the "Play" field in the "Pause/Play" group up under the "File" tab.
A response is supposed to be an input compared to an output, displaying the correlation. If not, its just a measurement.
So I would expect Omnimic (claiming a frequency response) to initiate, say, 3 sweeps and display the averaged correlation.
To my surprise, the "help" menu says nothing about how to get the test signals out of the computer thru Omnimic.
Half the "input/output story" is simply missing, despite Bill is being very thourough with everything else.
I have tried:
1. Headphone output (3mm jack) which produced hum and noise and a very faint signal (using music thru VLC player). Two different cables.
2. A Dragonfly USB to 3mm jack non-syncronious converter which worked excellent with headphones and the amp. for the speaker under test (still using music thru VLC player).
But nothing thru Omnimic.
Questions:
A. Is Omnimic using left or right channel from the headphone out ?
B. Is a mono, L+R device/cable needed ?
C. How to windows-configure the output device from Omnimic (jack / USB) ?
D. I have downloaded the test files, but where are they supposed to be stored for Omnimic to "find" them ?
I am probably missing the obvious, but nevertheless in both confusion and despair.
I normally use Clio in my "lab", but my version it is not very portable.
So I purchased Omnimic V2 a while ago, and now finally got ready for actually using it.
All the matching with the software and the mic. cal. code went well, and I have a spectrum on my screen with a live curve bouncing with noise in the room.
The mic. is obviously "hot".
But I do not succeed in making a sine-sweep response (or anything else) when I "press" the "Play" field in the "Pause/Play" group up under the "File" tab.
A response is supposed to be an input compared to an output, displaying the correlation. If not, its just a measurement.
So I would expect Omnimic (claiming a frequency response) to initiate, say, 3 sweeps and display the averaged correlation.
To my surprise, the "help" menu says nothing about how to get the test signals out of the computer thru Omnimic.
Half the "input/output story" is simply missing, despite Bill is being very thourough with everything else.
I have tried:
1. Headphone output (3mm jack) which produced hum and noise and a very faint signal (using music thru VLC player). Two different cables.
2. A Dragonfly USB to 3mm jack non-syncronious converter which worked excellent with headphones and the amp. for the speaker under test (still using music thru VLC player).
But nothing thru Omnimic.
Questions:
A. Is Omnimic using left or right channel from the headphone out ?
B. Is a mono, L+R device/cable needed ?
C. How to windows-configure the output device from Omnimic (jack / USB) ?
D. I have downloaded the test files, but where are they supposed to be stored for Omnimic to "find" them ?
I am probably missing the obvious, but nevertheless in both confusion and despair.
Thanks markbakk
Yeah I did.
As I said, I was missing the obvious. Got it now.
I have now realised it does not make responses.
One is supposed to simply play the tracks and stick the microphone in front of the speaker.
I.e. a level measurement.
But still a question, now I have worked a little with it:
If you set the time-window to 2 mS it still merrily displays frequencies below 500 Hz. In fact all the way down.
Magic ?
Yeah I did.
As I said, I was missing the obvious. Got it now.
I have now realised it does not make responses.
One is supposed to simply play the tracks and stick the microphone in front of the speaker.
I.e. a level measurement.
But still a question, now I have worked a little with it:
If you set the time-window to 2 mS it still merrily displays frequencies below 500 Hz. In fact all the way down.
Magic ?
Allright, then. Risky for the unwary, though.
It would have been nice if the red trace in the time-domain was reflected in the frequency-domain; where to "take a grain of salt" so to speak.
Gating you say ? Hmm. To me it does not seem so.
I suddenly come to think that maybe the test signal just holds a trigger for a steep tracking filter, running with the sweep.
That would reduce noise and some effects of reflections in a room, and do a decent level measurement.
Anyway, Bill has done a great job and Omnimic is great for a quick check on the go with a portable device which was what I needed..
It would have been nice if the red trace in the time-domain was reflected in the frequency-domain; where to "take a grain of salt" so to speak.
Gating you say ? Hmm. To me it does not seem so.
I suddenly come to think that maybe the test signal just holds a trigger for a steep tracking filter, running with the sweep.
That would reduce noise and some effects of reflections in a room, and do a decent level measurement.
Anyway, Bill has done a great job and Omnimic is great for a quick check on the go with a portable device which was what I needed..