HOLMImpulse: Measuring Frequency & Impulse Response

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My mistake, I was looking at H4.

Here is the plot. For H4 and higher harmonics they are all below -90 and all match live and imported. What do you see on the higher order harmonics?
 

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Administrator
Joined 2004
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Thanks for the config file. I can't load it because you have a later version of HOLM than I.
Yours reports V 1.4.2.6 and mine is 1.4.2.0 I didn't know there was a later version. Is yours for 64bit?

Anyway, the config.xml looks different enough not to work. And maybe it's a version difference between mine and your that is at the root of the differences we see.
 
Hi,

In first I want to congratulate You - amazing project!


I use Speaker Workshop. In SW pattern signal for left channel is compare with signal from Right channel (signal from microphone).
After this compare You get chart in your screen. Before measurement you must calibrate Speaker Workshop - inpute amplitudę must be about 16k.

Could You tell us how it's work in HOLMimpulse?
 
Just another Moderator
Joined 2003
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Hi Thomas, you can limit the lower frequency during the measurement if you choose a logarithmic sine sweep. Go to the Device and Signal tab and select Logarythmic Sine sweep, and then set the starting frequency to 1000.

I thought that you could set a low and high pass on the measurements tab (post measurement) but it doesn't seem to be having an effect. Perhaps try setting it before you measure and see what you get.

Tony.
 
Hi Thomas, you can limit the lower frequency during the measurement if you choose a logarithmic sine sweep. Go to the Device and Signal tab and select Logarythmic Sine sweep, and then set the starting frequency to 1000.

I thought that you could set a low and high pass on the measurements tab (post measurement) but it doesn't seem to be having an effect. Perhaps try setting it before you measure and see what you get.

Tony.

Thank you, Tony!

Works like a charm:cheers:

/Thomas
 
Hi,

I'm trying to convert a FRD file (frequency response measurement data, 1443 lines from 0Hz to 24kHz) to the equivalent impulse response using HOLMImpulse.

I'm able to successfully generate the impulse response by importing the FRD file as a measurement and then exporting the impulse response. My issue, however, is that the resulting file has a 44.1kHz sample rate, and I didn't find a way to change that. I would like to generate a 48kHz impulse response because I actually need the data between 22.05kHz and 24kHz (it's a long story).

So my question is: is there a way to export an HOLMImpulse measurement to an impulse response with a sample rate other than 44.1kHz? If not, I would like to make that a feature request.

Thanks!
 
Hello,

I am using a m-audio Fastrack C400 soundcard.
Using a phantom XLR input for the mic.
And a digital coaxial output to send the stream to a Minidsp.

I am wondering, How can I calibrate this soundcard? given that the output I am using is digital?

I am starting to think I should connect a balanced output in the Minidsp to the balanced input in the soundcard?

What makes sense?

Cheers,
Carlos
 
Just another Moderator
Joined 2003
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All my cards have been very flat with respect to frequency response, but oddly the phase hasn't been. I like to do the calibration to ensure the phase is nice and flat as well.

Charly I think your idea of connecting a balanced output from the mini DSP to the balanced input of the sound card makes the most sense for doing a calibration.

Tony.