Hornresp

Hmmm... turns out an LRC notch filter has potential to tame the beast...

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So now you are making me wonder if an FRD file import could be a new option for the generation of the correct Semi-Inductance model within Hornresp.

Let me change this a bit.

David could you possibly incorporate a FRD resistance/phase file import option to do the semi-inductance measurements in Hornresp? Many of us have the ability to measure a driver and export an FRD file. And from this I think you could extrapolate the necessary data to create the extended data set.
 
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Hi freddi,

1. Import the attached record and edit the driver and enclosure parameter values as necessary.
2. Use the Loudspeaker Wizard to adjust the absorbent filling material in segment 1.
3. The system response is given by Output 2.

Kind regards,

David
 

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Would it be possible to implement your suggested optional approach using an Excel spreadsheet, perhaps?

Now don't you go trying to plant that seed in my head, LOL. I've got enough work as it is maintaining the design workbooks... :)

Technically, doing it in Excel should be possible. And Excel does provide the goal-seeking algorithm built in.
 
Now don't you go trying to plant that seed in my head, LOL. I've got enough work as it is maintaining the design workbooks... :)

Technically, doing it in Excel should be possible. And Excel does provide the goal-seeking algorithm built in.

There is a forum member here who has done this already. We have been discussing it quietly in the background. So no pressure on you Master Steele. Your spreadsheets are pretty cool.

Still waiting for a front loaded horn folder! :D
 
many thanks David - its interesting to see that a notch in displacement can occur below 20Hz - would that hold up under various reasonable drive levels with such a small interconnecting vent? - being internal no one should hear it wheeze (unless through the cone. BEST ! Freddy

Hi Freddy,

The model I suggested is the closest that you can get using Hornresp, but it is by no means perfect :). Hopefully the power response prediction should be reasonable though, provided that the Output 2 result is used.

It appears that the notch you are seeing is due to the effect of the very small hole in the second chamber. Notice how if you increase S5 to 1.00 sq cm for example, the notch disappears. I have no experience with dual chamber designs, but presumably the notch would not be present in a practical system, if the second chamber was completely sealed.

For a serious analysis it would be safer to use AkAbak, but I gained the impression that you were looking for an indicative result only, which is why I was prepared to provide the suggested Hornresp "compromise" model :).

Kind regards,

David
 
Is possible to calculate whith Hornresp Helmholtz resonator like Technics SB-7000?


Hi Orion33,

Yes, bass-reflex systems can be simulated in Hornresp. The easiest way to get started is to create a representative design using the Input Wizard, and then change the input parameter values to suit. Select:

Help > Input Wizard > Half Space > Direct Radiator > Ported Box ......

Kind regards,

David
 
Yes, bass-reflex systems can be simulated in Hornresp. The easiest way to get started is to create a representative design using the Input Wizard, and then change the input parameter values to suit.
Thank you for answer, David.


But Helmholtz resonator is not bass-reflex system. See please picture
sb-7000(1).JPG

Resonanse camera is not connected to main box whereas bass reflex port is directly connected. I tryed create think section with maximal acoustical lining resistance but its behavior is diffrent from closed box. Or am I wrong?