OminMic and PCD - the great FRD Conundrum

[Jeff B.]

I have been receiving a lot of emails from people sending me frd files created with OmniMic that won't load in the Passive Crossover Designer, asking me if I can tell them why. Because this is a common issue based on the number of requests, I felt I should post a response on the forum

One thing I have found is that if the frd file from Omnimic doesn't have phase data of some kind, providing three columns of data in the file, I can not load it into any software I have, PCD or otherwise. I have even tried to manually type in a third column, but that was unsuccesful too.

When I am sent a file that does have phase data but won't load I just have to delete the first and last lines and save it, and it seems to load after that. But most of these have data that is really not fit for crossover development, but that's another issue altogether, having more to do with how the measurements are made than anything else.

I don't know exactly what it is, but there is something about these frd files that are different than frd files from other software that I have used, because I have loaded files from several other measurment systems without issues.

I would be curious if anyone else is finding the key to using them? I would also be curious if Bill W. is loading them straight into other software without issue? I assume there was beta testing of this before the release. I would like to know if any issues were found with regard to this?

Jeff B.

[Brewski]

Jeff,

if you open the files in Excel what and right click to format cells in the number tab what is the selected format for the cells data? I've seen on occasion the fields in a format like text that some the of the FRD tools doesn't seem very happy with but I've not worked with an FRD from Omni mic as of yet.

Take it easy
Jay

[arlis_1957@yahoo.com]

thanks for your effort jeff. i hope we get this resolved. if i cant use the files in rm and pcd, i dont have much use for omnimic.
brewski, if you would like, pm me your e-mail and ill be glad to send you a couple of omnimic frd.

[Jeff B.]

Jeff,

if you open the files in Excel what and right click to format cells in the number tab what is the selected format for the cells data? I've seen on occasion the fields in a format like text that some the of the FRD tools doesn't seem very happy with but I've not worked with an FRD from Omni mic as of yet.

Take it easy
Jay

frd files should be simple text files of three columns that are space or tab delimited. I can manually type one up in a text editor that will load fine.

Jeff

[dlr]

I would be curious if anyone else is finding the key to using them? I would also be curious if Bill W. is loading them straight into other software without issue? I assume there was beta testing of this before the release. I would like to know if any issues were found with regard to this?

Jeff B.

Zip a sample that won't load and make it available for folks to download and examine.

dlr

[neildavis]

Zip a sample that won't load and make it available for folks to download and examine.

dlr

+1

I've got an "FRD read" routine that I would like to test.

[Jeff B.]

+1

I've got an "FRD read" routine that I would like to test.

Here's two files that were sent to me:

http://www.box.net/shared/3833szbgs0


http://www.box.net/shared/55bdnhjcgc

I tried different things with them but were unsuccessful.

Jeff

[arlis_1957@yahoo.com]

why would a frd have three columes?
here is a sample of two. da115 and dayton titaium dome. sorry, this wont allow zips. email me and i will send them to anyone interested.

[bwaslo]

I think I see the problem, from the first file. On the line that is around 145Hz, there is no space between the frequency and the dB value. A bug in OmniMic, I imagine, some data values appear to print with more digits than they ought. I'll take a look at the code and issue an revision if that is the case. Sorry about that.

-Bill

[bwaslo]

I don't see anything wrong with the second one, though. Loads into Praxis fine. (The first one loads into Praxis, too, but only up to 144Hz).

[arlis_1957@yahoo.com]

thanks for dropping in bill. thanks to you to jeff for your efforts.

[neildavis]

Here's two files that were sent to me:

http://www.box.net/shared/3833szbgs0


http://www.box.net/shared/55bdnhjcgc

I tried different things with them but were unsuccessful.

Jeff

I can read and plot both of them, but the first one is missing a delimiter at F=145Hz. So my FRD read routine thinks that value is 0:


Also, it has a lot of sample points: 1912. Does the PCD import routine have an upper limit on the number of samples?

The other file only has 478 samples. The numbers look OK in Excel and there doesn't appear to be any maverick characters. However, the data values are silly--the maximum SPL is too low, and the bass relative to the high frequency response doesn't make any sense.

[Brewski]

Arlis to fix your DAY115 frd file here's what I did.

1st opened file in excel and selected the data in the column, then selected data drop down menu (text to column), selected delimited then next, added space as delimiter clicked next, select finish.

2nd added column of zeroes for phase in column C

3rd control a to select all data, select data tab and format cells in the drop down, select protection tab, de-select locked and save frd file (I'd guess this is what's causing the problem)

Before re-saving the frd file I couldn't open it in RM after the changes I can open it in RM.

Take it easy
Jay

[arlis_1957@yahoo.com]

wow, way over my head.

[Brewski]

wow, way over my head.

Sorry occupational hazzard I tried to add some more information to the previous post to make it easier to understand. You'll probably want to leave the post open as you follow the steps and it'll be easier to understand then I hope.

Take it easy
Jay

[bwaslo]

If your software requires a third (phase) column, it would be easiest to turn the phase ON in OmniMic before saving. To do that, check the "advanced features" checkbox, then the "phase" checkbox. When you save when phase is shown, the phase also gets saved.

Has anyone figured out why Jeff's second file doesn't load? The curve does look bizarre, but the file format looks ok to me (and to Praxis).

[Brewski]

If your software requires a third (phase) column, it would be easiest to turn the phase ON in OmniMic before saving. To do that, check the "advanced features" checkbox, then the "phase" checkbox. When you save when phase is shown, the phase also gets saved.

Has anyone figured out why Jeff's second file doesn't load? The curve does look bizarre, but the file format looks ok to me (and to Praxis).

Same steps fixed Jeff's second file for me.

Take it easy
Jay

[bwaslo]

I don't get it.. how could an FRD file be "locked", that's an Excel thing?

What does your process change in the file?

[arlis_1957@yahoo.com]

what am i missing? a zma should have two columes, impedence curve and phase data. a frd file should have two frequency and phase. please explain the third.

[Jeff B.]

If your software requires a third (phase) column, it would be easiest to turn the phase ON in OmniMic before saving. To do that, check the "advanced features" checkbox, then the "phase" checkbox. When you save when phase is shown, the phase also gets saved.

Has anyone figured out why Jeff's second file doesn't load? The curve does look bizarre, but the file format looks ok to me (and to Praxis).

Once we get a little more information squared away on these files, if I can figure out what to change in my VBA routine that will help the situation, then I will make that update.

Like I said above, I can usally load files from a lot of different measurement systems, so I am surprised that these don't want to cooperate.

Jeff