HOLMImpulse: Measuring Frequency & Impulse Response

It appears that the mic EQ contains almost 10 dB of boost at the high end. Not a very good mic I would say. Or the cal file is wrong.

Yes, this Superlux ECM 888B is a cheap 50€ microphone and yes, the calibration file is not correct, although the guys from Hifi-Selbstbau - Startseite did everything right in their measurement setup.

But that's not my point. I was surprised what HI did with the original values during the import of the cal file.

But this "transformation" seems to be consistent. I now have compared the ARTA measurements with the HI measurements and both are congruent.

Whatever HI is doing: It fits. For now I am reassured but not satisfied.

Lojzek: I did follow your advice.
 
I'm failing to measure FR for some twetter (Klipsch K-77M). Impulse windows shows complete mess and on FR there is not anything useful. From signal configuration I see that min measuring freq is 1kHz. Can my problems come from fact that this tweeter don't have much output below 2kHz? Can I do something about it?
I had no problem to measure complete (3way) speaker with XO or "better" twitter alone.
 
Technical issue with HOLM

I had to change computers and decided it was time for a new interface. Got a Komplete Audio 6.

My problems:

Often while using Holm I get an error message and application closes. If i try to do a loopback calibration, it would pop up all the time and even if I chose "continue", it closes. I use it on a core i5 with 4GB of memory, Gforce 920 and Windows 10. The HOLM is 64 bit version.

Second problem is I am unable to measure distortion now, it just doesn`t show up. Tried anything, no luck. The driver in use is Asio in HOLM, installed is Asio4all, but I also tried MME with no resolution. Harmonics now just show NA.

Tried reinstall, reboot and etc, nothing works. Here is a screenshot of the error message (pic below).
 

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Best smoothing method for measuring at listening position.

Amplitude or complex? Which one is better? They give me dramatically different results. See the pictures (1/3 and 1/6 smoothing). Same measurements, different smoothing methods. I'm trying to eq speakers to target curve.
 

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Complex smoothing is what you want. The term "complex" is poorly chosen since it is not "complex" in the mathematical sense, but in the fact that it is more complicated.

Complex smoothing is not constant across the bandwidth, but gets wider as the frequency goes up. This is much more like the way that we ear. for EQ purposes the "complex" 1/3 octave would be your best choice.

It does appear to me that your gating is too long - too many room reflections.
 
The term "complex" is poorly chosen since it is not "complex" in the mathematical sense, but in the fact that it is more complicated.
Holm uses Complex in the context of fractional octave smoothing to refer to independently smoothing the real and imaginary parts of the response rather than their magnitudes, so Complex seems appropriate.
 
Interesting. I could not get the first paper since I am no longer an AES member (retired), but I had the second one. It is quite complete in its analysis.

I was initially suspect since it is possible to smooth a complex function in the complex domain, I've done that, so I did not see why one would do it separately on the real and imaginary parts. But since one takes an expected value of the squares, (which is not linear) this will account for the difference.

Thanks for the info John.
 
I have been using holms for a couple of weeks now and have been importing data from REW without issue but now it will not import and when I try to import Holms crashes I have read through the thread and the manual searching for import but cannot find the same issue I have removed and redownloaded and installed Holmsimpulse REW and Java. Holms will still import older files but will not import new files. thank you
 
Since you have been able to import/export before I'll assume you're exporting from REW as a text file (vs an impulse response) and that you have both programs set up to use the same comment character (typically the asterisk character) for the header lines.

You can still run into hang-up problems if REW creates comment lines that are longer than 80 characters. REW will hangup on those. You can edit the header lines so they are under 80 characters or just delete all header lines.
 
You can still run into hang-up problems if REW creates comment lines that are longer than 80 characters. REW will hangup on those. You can edit the header lines so they are under 80 characters or just delete all header lines.

Oops! I meant Holm will hangup on header lines longer than 80 characters, not REW. Evidently you understood what I meant even with the typo.