Hi Piyapong38,
Sorry, but I am not sure what it is that you are asking - your references to "back room", "capacitance" and "channel section" have me very confused
.Vrc is the volume in litres of the speaker enclosure, if that helps.
Kind regards,
David
Hi Piyapong38,
Sorry, but I am not sure what it is that you are asking - your references to "back room", "capacitance" and "channel section" have me very confused
Vrc is the volume in litres of the speaker enclosure, if that helps.
Kind regards,
David
Hello david
I know you can help me.
Vrc is the volume in litres of the speaker enclosure.
I want to know Vrc is the volume in litres Must delete is the volume of the speaker
or not?
Thanks in advance David
... It seems that just when I think everything is finally working as intended, I always manage to find something else that requires attention
That's the law of cybernetic entomology: There's always one more bug.
Hi Piyapong38,
It's all in the Hornresp Help file
."The rear chamber volume is the effective enclosed air volume behind the driver diaphragm, including any space occupied by acoustical lining material but excluding port tube, driver magnet and chassis assemblies."
So yes, the volume of the driver or "speaker" protruding into the rear enclosure must be deleted - it is not included in the value of Vrc. The reason it must be deleted by the user is because Hornresp does not know the volume occupied by the driver. All the program knows about the physical size of the driver is the value of Sd.
Kind regards,
David
Hi Piyapong38,
It's all in the Hornresp Help file
"The rear chamber volume is the effective enclosed air volume behind the driver diaphragm, including any space occupied by acoustical lining material but excluding port tube, driver magnet and chassis assemblies."
So yes, the volume of the driver or "speaker" protruding into the rear enclosure must be deleted - it is not included in the value of Vrc. The reason it must be deleted by the user is because Hornresp does not know the volume occupied by the driver. All the program knows about the physical size of the driver is the value of Sd.
Kind regards,
David
Thank you David
Addenda
Steps to calculate driver occupancy volume:
1) Calculate front side cone cavity volume using HR tools.
2) Front-mount and then-back mount the driver on a test box and determine the system resonant frequency for each position.
3) From these measurements, then calculate the decrease in air volume necessary to cause the increase the system resonant frequency.
4) From this figure subtract volume calculated in step #1.
If you then line the test box with the acoustic resistance material you are going to use and the note the weight increase of the test box as well as the change in system resonant frequency, you will also have an estimate of frequency change per unit weight of material used in your final system design. If you are using both liner and filler materials then this will be a two step measurement process.
N.B. You will need the test box to measure/verify driver TSPs anyway.
Do not trust MFG's specs. They are almost always given sans tolerances.
Typically what you get commercially are those units that do not meet OEM test specifications;
i.e., the volume, OEM client gets "pick-of-the litter".
WHG
Hi Piyapong38,
It's all in the Hornresp Help file
"The rear chamber volume is the effective enclosed air volume behind the driver diaphragm, including any space occupied by acoustical lining material but excluding port tube, driver magnet and chassis assemblies."
So yes, the volume of the driver or "speaker" protruding into the rear enclosure must be deleted - it is not included in the value of Vrc. The reason it must be deleted by the user is because Hornresp does not know the volume occupied by the driver. All the program knows about the physical size of the driver is the value of Sd.
Kind regards,
David
Steps to calculate driver occupancy volume:
1) Calculate front side cone cavity volume using HR tools.
2) Front-mount and then-back mount the driver on a test box and determine the system resonant frequency for each position.
3) From these measurements, then calculate the decrease in air volume necessary to cause the increase the system resonant frequency.
4) From this figure subtract volume calculated in step #1.
If you then line the test box with the acoustic resistance material you are going to use and the note the weight increase of the test box as well as the change in system resonant frequency, you will also have an estimate of frequency change per unit weight of material used in your final system design. If you are using both liner and filler materials then this will be a two step measurement process.
N.B. You will need the test box to measure/verify driver TSPs anyway.
Do not trust MFG's specs. They are almost always given sans tolerances.
Typically what you get commercially are those units that do not meet OEM test specifications;
i.e., the volume, OEM client gets "pick-of-the litter".
WHG
Last edited:
S.O.S.
Hi David,
Need O.S. as first segment of a multi-segment horn. Segment #2 would be a Le Cleac'h bell. Would you be willing to implement this in HR? I am willing to help with the programming.
Regards,
Bill
Hi David,
Need O.S. as first segment of a multi-segment horn. Segment #2 would be a Le Cleac'h bell. Would you be willing to implement this in HR? I am willing to help with the programming.
Regards,
Bill
Hi Bill,
As much as I would like to be able to help out - particularly given the very valuable and highly tangible assistance that you have generously provided to me over more years than I care to remember, unfortunately the way that Hornresp is structured, the work now required to seamlessly integrate the requested additional functionality would be more than I am in a position to undertake. As you are aware, having been one of the very first Internet users of Hornresp, the program has grown significantly but in a rather haphazard fashion from very simple beginnings. If I knew at the start what I know now, the program architecture would have been set up initially quite differently, but I had no idea then that Hornresp would morph into the program that it has now become. It was originally written just to simulate the throat acoustical impedance and power response of a Klipschorn style bass corner horn - that's all!
Your offer of assistance with the programming is very kind, but it is not the simulation model that is the problem for me, rather it is all the changes that would need to be made to the user interface and the ancillary tools, that make the task overwhelming.
Multiple-segment horns were originally confined to Con and Exp flares with the Par flare option being added at a later date. I assumed that multiple segments would be used to specify low expansion rate bass horn systems only, so provision for other flare types was not made back when it would have been much easier to do so.
Hope you understand my situation
.Kind regards,
David
Hi BP1Fanatic,
Earlier posts starting from 20th June 2007 (when I joined diyAudio) are spread over a number of different threads. If interested, they can be found by conducting an Advanced Search on my user name. Specify the results as posts, sorted in ascending order.
My email correspondence with Bill goes back years before 2007
.Kind regards,
David