Dayton OmniMic Precision Measurement System - Page 53

Just a small FYI, PE emailed me back about my potential faulty MIC and said they are offering a free recalibration for anyone with the older MIC and suggested it be sent in for a recal.

If anyone needs more details I can copy and paste the email or you can hit up their technical support.

James there is no impact whatsoever with the V1's that were and are being recalibrated.

-Rich

Thank you for the information Rich.

James

Their technical support got back to me ASAP with the address to send my V1 mic. It's not so much having a problem that concerns me, it's how it's handled and I am very satisfied with the handling of the situation to this point. Kudos

My initial omnimic had some issues and I had to send it back in. The Parts Express guys took good care of me. Thanks guys, I look forward to doing more business with you as I build up my studio.

Any update or feedback on the situation with the mics ? Everyone happy, received their goods ? Just thought I would bump the thread and find out.

Still waiting for my V2 to arrive. Bob

New OmniMic owner here. Could someone give me the step-by-step for getting measurements to help identify the best location for sub placement. I have a little experience doing this with REW, though it's been a while. I can't quite figure out how to do it with OmniMic (I have v3.10). Thanks!

I have been finding that when I go to open some of my saved curve list files that nothing is showing in Omni. In case anyone also sees this problem you may want to take a look and see if this can fix your issue.

What I have found is that is you open the saved curve list file in notepad a line is missing that actually points to where the curve file is located. What you can do is edit the file and add the top line back in and then the curve file should load with no issues.

I have attached to snips showing this.

The first one shows a curve list that will not load any data.

The second one shows a curve list after I have added in the path needed and will now open in Omni.

I do not know why this is taking place but it will fix the issue.

James

The OmniMic V2 is a vast improvement over the V1. They really listened to user feedback when they worked on this thing. All six of my hardware complaints were addressed, obviously long before I posted them. The new mic clip is much better, the new USB connection is strong, and the mic can now be dangled by the cord without fear of the mic slipping off the connector. The little rubber gaskets don't roll off as easily.

V2 even comes with a little pouch and a mini-tripod with rubber feet for setting the mic on a table. The new carrying case is the same sturdy plastic that holds my wireless microphones, I can now throw my OmniMic in with the rest of my gear with worrying about the case shattering.

Great work! I'm really happy with this OmniMic and intend to buy another for my other mobile set.

Can we order a v2 mic as a standalone so I can replace my v1 mic?

Dave.

How much does the V2 measurement system cost? Can it be purchased at PE? Also, how does it compare to REW? I am in need to a way to measure my room, and, the cost of a sound card + mic+ spl meter + mic pre-amp, is around $300.00, which I believe is what I saw quoted for the Dayton system. Is $300.00 correct for this?

298 from PE so basically 300.

James

can anyone post the link to the new v2 omnimic please?

Setup the mic in the listening position
Use the bass decay tab
Pick the correct track
Play bass track, then watch the bass decay/response as you move the sub around, pays to have a helper to move the sub around so you can concentrate on the graphs.
Another way, if you are restricted with sub placement is to move the mic/listening position around a bit, even a combination of both can help.

Another thought make sure you play the tracks at least 75db. If the graphs aren't stable, jump around a bit, by turning the volume up can decrease this.

PE has fouled up my replacement order but they are trying to rectify. Someday I will have a properly working V2!

-Bob

Thank you for the reply Phillips751! Can I ask another question? How do I get a graph similar to this:

You need some very capable subs and a pretty darned good room!

That can be found in the frequency responce tab. Check the "help" section of the program and it will give you more information of what is there.

James

Looks good, but i would check the bass decay to make sure that looks good.
I can get a reposnse similar but there is decay past 450ms until i make changes.

Seems I wasn't clear in my last post... how do I use OmniMic to take a reading like that in the example graph I included in my post above?

Refer to James post #1580 about the frequency response and for the smoothing to the right there is a drop down box.
If you don't know how to use the Omnimic i suggest to read the manual which is in the frequency response tab on the top, called help. Then click on the topic, in this case Frequency Response. If you have any questions after that post back with them.

Okay... in an attempt to see the FR of my subwoffer... I disconnected by FR and FL speakers. I set my receive volume to -15 and turned off Audyssey/EQ. I selected the Frequency Response tab with the following settings:

• Sine Sweep
• Blended 5.0 msec
• Smoothing = None

I then played Track 2 (Monophonic Short Sine Sweep) from the test CD, right clicked and chose Save Snapshot to Graphic File. My result is attached.

Did I do this correctly?

So I received my mic back from PE for the re-cal and was finally able to get some measurements done.

I took reading from 6 different locations. 3 from on the couch (considered back row) and 3 from right in front of it since that is the area I am usually sitting in my chair (considered front row). The area the measurements cover is about 6 wide and 3 deep.

All measurements were taken at -5 MV from the Onkyo 885 with a 1-24th smoothing.

The way I did this was take a measurement from position 1 with only the subs.

Left the mic in that place and then turned on the speaker amp and took a reading for both the speakers and the subs. I did that for all 6 positions measured.

For the speakers only, I just turned off the sub amp and then took the measurements one at time in 6 different locations. Same general position for the mic but not 100% the same as the positions when I did the subs and speaker step.

The three screen shots showing below are (with back row=black, front row=red, blue average of the positions):

1) subs only
2) subs and speakers
3) speakers only (no average in this one)

One suggestion I would like to make in regards to Omni software. When individual frd files are loaded, say I load three and make them all the color red, when a snapshot is taken, it should leave the colors as I selected them. I attempted to get snapshots of these but every time it changed each frd file to its own color and not what I had made them.

James

What i do is turn off speaker A (mains) and then run the sub at full range, using the receivers volume.
Reason for running the sub at full range is because the crossover isn't a brick wall, there is still output beyond the crossover point, so it contributes to the sound.
I also run the speakers at full range for the same reason, then make the crossover settings after.
Also use the 1/6 or 1/12 smoothing, depends what you prefer.
Use the auto feature up at the top right, don't forget to turn it off after a few seconds. The arrows around the frequency response are handy to adjust the graph accordingly. The auto tick box on the bottom left (between the reponse and impulse) is for automatically adjusting the graph scales. That is why your graph is cut off.

Hope that helps. Post back your results to see the result.

James at matter of interest did you find much of a difference with the calibrated mic vs uncalibrated? Was it worth it to send back?

Can you post some before and after results?

I am not able to 100% assure the mics location was the same for a before and after recal measurement so I just do not feel confident in saying there was a difference.

What I can say is the measurements I took before and after in the same areas show the same "style" of measurement. I am sure you have read that moving the mic just a few inches can change the results. I will post some of them later on when I have a bit more time but again, I do not consider them apples to apples.

One last thing, it was worth it to me just to have the mic looked at again and also calibrated down to 5HZ were before it was only calibrated to 10HZ.

James

Here are five before and after recal measurements. All measurements were running the master volume at -5.

Again I want to state that the mic position was probably off a few inches in both the standing area and height so I will not say these are apples to apples. What I wanted to see if how they followed each other and to me they pretty much do.

These only go to 10HZ since the mic was not calibrated to 5HZ until I sent it in.

James

Thank you James.
The POS 2 seems to have the most differential.
Where these taken with the subs only?