First Development version of Boxsim in english language

[goofy_ac]

You´re welcome - it´s seldom enough that I as a youngster can give some advice

[Willy_65]

Hi Willy

All tweeter with WG´s have a different set of data for boxsim - you have to exchange them.
Boxsim -> Chassis: select your tweeter (G25FFL) -> load from file -> G25FFL-8_WG.BCH

Thats it - as far as I know

Now I understand why I often see WG tweeters in use but not for sale
That will certainly be the solution, thanks for the quick response !!

[goofy_ac]

Hi Willy

All tweeter with WG´s have a different set of data for boxsim - you have to exchange them.
Boxsim -> Chassis: select your tweeter (G25FFL) -> load from file -> G25FFL-8_WG.BCH

Thats it - as far as I know

[Willy_65]

I am optimizing the Couplet Light for use with tube amplifiers. So a better impedance curve is a priority.
I achieved all that, including a better acoustic power response.
Therefore I also had to use the dome tweeter G 25 FFL.
Now I get a frequency response with @ 6dB = 47Hz- @ 10dB = 36Hz-30kHz.
To achieve an even better spread for the tweeter I will use the waveguide WG 148 R, for which I have to adjust the height of the box from 46 to 52 cm.

My question now is: Is it sufficient that I select in "enclosure and baffle / baffle and position" under "shape of diaphragma" Waveguide and nothing else?
I use the option "Common outer housing"

I don't see any difference under "Frequency response".

[mcl2k6]

Not in this thread. This one is for the english version of Boxsim.
Please open a new thread and maybe attach the project file because frequency response is not the only interesting topic.

Did it: http://forum.visaton.de/showthread.p...449#post451449
Thank you!

[UweG]

Not in this thread. This one is for the english version of Boxsim.
Please open a new thread and maybe attach the project file because frequency response is not the only interesting topic.

[mcl2k6]

Thanks UweG for clarifying even further!
Currently, I have something like the one attached to the post. Any comments on it?

[UweG]

Translatet by Google

As I read that I thought it was a joke, but in fact it isn't.

Let me try to improve the translation anyway:

The acoustic power response (so called in the english version of Boxsim) is the frequency response of the sound energy that is radiated by a box, regardless of the direction in which the sound is emitted.

Frequency responses usually refer to the sound a box radiates straight forward. Indeed, in a low-resonance room (anechoic chamber), one observes that speakers with similar frequency response in the main emission direction also sound similar when sitting in front of them. The same can be observed under free-field conditions. In a living room, however, one notes that speakers with the same frequency response on the axis sometimes produce a very different sound color. The reason for this is the indirect sound. That means sound components that do not get straight from the speaker to the listener, but are partly reflected several times on the floor, ceiling, walls or pieces of furniture before they reach the ear of the listener. Obviously, this sound originally did not necessarily have to be emitted in the direction of the listener.

The sound power response provides a measure of how strongly the room is excited with diffuse sound components, which arrive as indirect sound at the listener. Especially if listened in a large distance and/or in a heavy reverberant room, it should be emphasized that the sound power frequency response in the range above approx. 250 Hz should be as flat as possible. The frequency response below about 250 Hz has little effect on the timbre, but is perceived separately as more or less bass.

In the german version I avoided to use the word Schalleistungsfrequenzgang (word by word translated: sound power response), because this is a word used in the german standard DIN EN ISO 3740, but with different meaning. In the standard 0 dB is defined as 1pW of radiated sound energy. This is not the 0 dB of sound pressure level (20µPa) in 1m. The difference is about 11 dB.
In Boxsim the sound power response is identical to the frequency responnse on axis, if the speaker radiates the same amount of sound in every direction.

[mcl2k6]

OK, thank you very much! It's clear now.

[walwal]

5. What is meant by energy frequency response?

The Energiefrequnzgang is the frequency response of the sound energy that radiates a box, regardless of the direction in which the sound is emitted.

Frequency responses usually refer to the sound a box radiates straight forward. Indeed, in a low-resonance ("dead room") room, one observes that speakers with similar frequency response in the main emission direction also sound similar when sitting in front of them. The same can be observed under free-field conditions. In a living room, however, one notes that speakers with the same frequency response on the axis sometimes produce a very different timbre. The reason for this is the indirect sound, that is, sound components that do not get straight from the speaker to the listener, but are partly reflected several times on the floor, ceiling, walls or pieces of furniture before they reach the ear of the listener. Obviously, this sound originally did not necessarily have to be emitted in the direction of the listener.

The energy frequency response provides a measure of how strongly the room is excited with diffuse sound components, which arrive as indirect sound at the listener. Especially with large hearing barriers and with reverberant rooms, it should be emphasized that the energy frequency response in the range above approx. 250 Hz is as straight as possible. The frequency response below about 250 Hz has little effect on the timbre, but is perceived separately as more or less bass.

http://www.boxsim.de/faq.html

Translatet by Google

[mcl2k6]

I would have a question: what does actually "Energy frequency response" mean on the FR graph on the main window?

[Willy_65]

Thanks Fraggle for de clear description.
Now I understand what you mean and I think you are right.
The exact location and size of the internal port determines the tuning frequency, I am convinced of that.
In this case, it is probably less important where the port's output is in the box and we should therefore only indicate that it is in the center of the panel. The other dimensions belong to the internal input of the port, but that is not really easy to enter in the tab of the port.

UweG (developer of the software) probably knows how to enter it correctly.

Update: I found another error when entering the geometric volume per AL130, I can only enter half of the total geometric volume there, so 13.1 instead of 26.1 ...

Moreover, I have found a tuning frequency of 45Hz in the official BPJ file of the COUPLET, perhaps I should also copy that myself.

[Fraggle]

Hello Willy,
I made a little sketch of my interpretation of the dimensions f, g, and k in this case.
If the inner end of the tube is close enough to a wall, the air flow is restricted to a smaller cross-section, which acts like as an extension of the tube length. Therefore it seems reasonable the dimensions I indicated should have an effect on the tuning frequency, although I don't know how the the tool works in detail. There is no such effect at the outer end of the tube.

[Willy_65]

I think it is correct, because what matters is the position of the inner end of the tube relative to the walls.
Consequently, the distance to the front and back walls should be entered as distance to the top and bottom walls.

I do not understand the latter well, I think I only have to deal with top-wall when entering "Distance to opposite wall (g) [cm]".
All the rest speaks for itself since there the position concerns the output of the port in the rear wall.

See attachment with my input values for the port in box COUPLET.
COUPLET construction plan also attached.

[Fraggle]

I think it is corrct, because what matters is the position of the inner end of the tube relative to the walls.
Consequently, the distance to the front and back walls should be entered as distance to the top and bottom walls.