In the absence of any further feedback, and until advised to the contrary, I will assume that the error message reported by more10 was a "one-off" non-repeatable occurrence. The reason for the generation of the message remains a mystery.
Kind regards,
David
Hi Art,
Further to my Post #3138 and just so that I understand, are you referring to a difference between the Helmholtz resonance frequency figure given in the Loudspeaker Wizard tool and that shown in the status bar panel at the bottom of the input parameters window when the mouse pointer is moved over Ap or Lpt, or are you referring to a difference between the Wizard figure and the position of the resonance on the SPL response chart?
The Wizard and status bar figures should be the same, but the chart resonance position would normally be slightly different - I can explain why, if interested.
Kind regards,
David
Hi Bart,
Select the Hornresp File > Find... menu command and have a play - it should soon become clear.
Kind regards,
David
import file name
Hi David,
with some friends, we are sharing files to feed HR, but we have a problem with the naming of the files, because neither export or import accepts more than 8 letters name.
It's a little annoying because we are sharing a lot of files so description is not accurate as it should be.
Could you do something about that ?
(longer names that is.)
Thanks for that and ALL the GOOD job you're doing.
Regards,
Blo
Hi David,
with some friends, we are sharing files to feed HR, but we have a problem with the naming of the files, because neither export or import accepts more than 8 letters name.
It's a little annoying because we are sharing a lot of files so description is not accurate as it should be.
Could you do something about that ?
(longer names that is.)
Thanks for that and ALL the GOOD job you're doing.
Regards,
Blo
I have noticed a difference between the Wizard Helmholtz resonance frequency figure and the position of the resonance on the SPL response chart.
I am interested in what causes the difference.
Hi Blo,
The 8 character file name limitation is a carryover from the original Fortran IV and early MS-DOS versions of Hornresp, which had no option but to use the 8.3 format. I would probably be prepared to increase the file name length a little, but not up to the 255 characters now possible with the later versions of Windows.
Would 16 characters be sufficient for your purposes?
Kind regards,
David
before jenny month pass.. happy new year david. i come lately. ok the mod may be change the day i post return to 1stdavid can u put the hotkey to calculate. i think i like more than click. hard work to do guy. this year hope u enjoy thanks
Hi Thawach,
Thanks - and even though it is now the first of February, a Happy New Year to you also
.Shortcut keys Alt+C or F5 can be used as an alternative to clicking on the Calculate command button.
Kind regards,
David
Hi David,
16 would be good, a little bit more (32 ?) would be better for a long time I think.
Perhaps the same length of the "comment" line, and,
, a default name for the file could be the comment ? Sounds logical to me.Regards,
Blo
Hi Art,
Thanks for the clarification.
The Helmholtz resonance frequency is calculated using the standard resonance formula:
fh = 1 / (2 * Pi * Sqrt(Ma * Ca))
This expression calculates the theoretical resonance frequency for an idealised vented-enclosure in that:
1. It does not take driver parameter values into account.
2. It assumes that the vented-enclosure is a perfect acoustical compliance Ca.
3. It assumes that the port tube (with appropriate end corrections) is a perfect acoustical mass Ma.
As the port tube becomes longer, the assumption that it can be treated as a pure acoustical mass becomes less accurate.
The reason that the Helmholtz resonance frequency is determined this way is simply to make the derivation a tractable problem capable of being directly solved. In reality, the vented-enclosure and port tube each have frequency-dependent impedances which make it impossible to find the exact resonance frequency using a simple formula.
The Hornresp SPL response model on the other hand, takes the frequency-dependent impedances into account - the simplifying assumptions inherent in the Helmholtz resonance frequency formula are not applied in this case.
This is why the two results are slightly different - theoretically, the resonance shown on the SPL chart should be the more accurate.
It is possible to make the two results effectively the same by:
1. Selecting the Hornresp 'resonances masked' option, which means that the vented enclosure is then treated as a simple compliance, the same as in the formula.
2. Setting Eg = 0 so that the driver parameter values are not considered, the same as in the formula.
In the attached example:
1. Inputs.png shows the calculated Helmholtz resonance frequency to be 34.06 hertz.
2. Freq1.png with resonances unmasked and Eg = 2.83 volts shows the position of the resonance at 33 hertz.
3. Freq2.png with resonances masked and Eg = 0 volts shows the position of the resonance at 34 hertz, which is now very close to the value given by the formula. There will always be a very small difference because the formula is still treating the port tube as a pure acoustical mass whereas the SPL response model is not. Also, as indicated earlier, the longer that the port tube becomes, the greater will be the difference.
Kind regards,
David
Attachments
Hi Blo,
The Hornresp comment field can be up to 76 characters in length - that's too long a file name for me. 16 characters it will be
.Hopefully I should be able to release an update sometime tomorrow.
Kind regards,
David
Hi Blo,
The Hornresp comment field can be up to 76 characters in length - that's too long a file name for me. 16 characters it will be
Hopefully I should be able to release an update sometime tomorrow.
Kind regards,
David
All right !!
Thanks for that !!
Regards,
Blo
To make things clearer I should perhaps have said "quite complex frequency-dependent impedances".
Kind regards,
David
Hornresp Update 3110-130202
Hi Everyone,
The maximum allowable length for Hornresp file names has now been increased from 8 to 16 characters. The file Open / Save form has also been widened to ensure that even under "worst-case" conditions, file names having 16 characters will be fully visible for all standard screen resolutions and text sizes - see attachment.
Kind regards,
David
Hi Everyone,
The maximum allowable length for Hornresp file names has now been increased from 8 to 16 characters. The file Open / Save form has also been widened to ensure that even under "worst-case" conditions, file names having 16 characters will be fully visible for all standard screen resolutions and text sizes - see attachment.
Kind regards,
David
Attachments
Thanks David,
This is great! I have some rather cryptic names in my export folder.
Hi Dan,
I'm glad you like it
.Blo06 really deserves the thanks, for suggesting the change in the first place.
For obvious reasons only version 31.10 or later will be able to save and open files having names longer than 8 characters.
Kind regards,
David
