Cabinet damping material needed in Mumbai

[Kevano]

In WinISD: Box ->Advanced->Qa

I found this - https://www.glasswolf.net/papers/polyfill.html
For a 1.4 cubic ft sealed box, using 1.75 lb/ft³ polyfill gave maximum volume gain 36% to get1.9 cubic ft.

I put Qa=4.08 for a sealed box volume=2.16ltr to get Qtc=0.7. But for a driver that needs 13.95ltr of Vb achieving Qtc=0.7 for Vb=2.16 by stuffing polyfill just doesn't look possible.

So how to go about figuring how many gms of polyfill will be required to take care of internal standing waves and lowering Qtc as much as possible for a Vb=2.16?

 

[keith_correa]

My notes say:
Qa = 100 = unstuffed.
Qa = 50 = walls lined.
Qa = 10 = stuffed
Qa = 5 = stuffed and stuffing = compressed

Did you try modeling the box in the Leonard Audio TL software. It will show you how much you need to stuff.

BassBox says this:

Also, did you put in a value for Ql [leakage]? That will affect Qtc too. IMO, you don't need to get too hung over Qtc. You have a box modeling program. Choose your response and let Qtc fall where it will.

 

[Kevano]

Did you try modeling the box in the Leonard Audio TL software. It will show you how much you need to stuff.

I downloaded the setup file from - https://leonard-audio.software.informer.com/
But get this error msg. Please check image. Have no idea if its my PC or the file itself.

IMO, you don't need to get too hung over Qtc. You have a box modeling program. Choose your response and let Qtc fall where it will.

Ok. I have seen a 16ohm version of my driver which has a higher Qts in an enclosure close to half my enclosures internal volume. Used with a sub of course. So I'll live with the Qtc I'm getting with the response I'm aiming for.

 

[keith_correa]

I downloaded the setup file from - https://leonard-audio.software.informer.com/
But get this error msg. Please check image. Have no idea if its my PC or the file itself.

That installer tries to download some files from the Leonard Audio website which does not exist any more. An offline installer was created - use this: https://www.diyaudio.com/forums/sof...n-line-modelling-software-17.html#post5160274

 

[Kevano]

I had found the offline installer on Pg81 - https://www.diyaudio.com/forums/software-tools/220421-transmission-line-modelling-software-81.html
Extracted the zip files to " C:\tline_installer " as instructed but no luck. This error msg pops up.

That installer tries to download some files from the Leonard Audio website which does not exist any more. An offline installer was created - use this: https://www.diyaudio.com/forums/sof...n-line-modelling-software-17.html#post5160274

I didn't find the installer on this link. I think you meant to copy the Pg81 link.

Any more ideas ?

 

[narcissus]

Hey Guys,

Any known CNC router 3axis 3D (wood) service provider in Mumbai? I have the necessary files in (Solidport) .SLDPRT / .dwg / .x_t (parasolid) but im told majority of the CNC service providers work with Corel Draw .cdr extension.

My priority is to find someone who can work with my existing file formats, if not then I need to convert the files to .cdr, which I'm not sure would yield the same results. I hope few of our members who are knowledgeable in this field can guide me.

Thanks in advance for all your help.

P.s. The .DWG file I suppose is a 2D whereas the others are 3D

 

[keith_correa]

I had found the offline installer on Pg81 - https://www.diyaudio.com/forums/software-tools/220421-transmission-line-modelling-software-81.html
Extracted the zip files to " C:\tline_installer " as instructed but no luck. This error msg pops up.


I didn't find the installer on this link. I think you meant to copy the Pg81 link.

Any more ideas ?

The application needs the .NET 4.0 runtime to run. You MAY not have that version of the Framework installed on your machine. Install the Framework from here: https://www.microsoft.com/en-in/download/details.aspx?id=17851

Then try again and report back on success/failure.

 

[Kevano]

Then try again and report back on success/failure.

 

[keith_correa]

Did you uninstall the version you installed from "https://leonard-audio.software.informer.com" before running the one in "C:\tline_installer"?

 

[drlowmu]

If using a tube amp, and the output transformer's entire winding is 8 Ohms on the secondary, with a 4 Ohm alternate choice....the amplifier itself will usually sound it's best using the entire secondary winding, ie the ground and 8 Ohm taps.

Jeff

 

[keith_correa]

Did you uninstall the version you installed from "https://leonard-audio.software.informer.com" before running the one in "C:\tline_installer"?

Please ignore this. I now realize that you could not install it at all and that the error message that you posted was on clicking the setup file.

Try the attached file. Strip off the .zip extension and open as a .rar file. Extract to a folder. Run "TransmissionLine.exe". It may throw an error. Just hit "Continue".

 

[Kevano]

Try the attached file. Strip off the .zip extension and open as a .rar file. Extract to a folder. Run "TransmissionLine.exe". It may throw an error. Just hit "Continue".

Operation successful. Eagle has landed. Now, figure out the eagle

If using a tube amp, and the output transformer's entire winding is 8 Ohms on the secondary, with a 4 Ohm alternate choice....the amplifier itself will usually sound it's best using the entire secondary winding, ie the ground and 8 Ohm taps.

Jeff

Ok.

This is an AVR (Marantz 1510) and I think it has class D amplification considering the price of USD650. The default impedance setting is 8ohm. Then in the setting there is an option to set impedance to 6ohm and 4ohm. Would something similar be going on on the AVR too?

 

[Hari Iyer]

I will be glad to know the driver CMS ( equivalent compliance) and MMS ( Moving mass). IME, only drivers with high compliance and low MMS work well in sealed enclosure

 

[drlowmu]

Ok.

This is an AVR (Marantz 1510) and I think it has class D amplification considering the price of USD650. The default impedance setting is 8ohm. Then in the setting there is an option to set impedance to 6ohm and 4ohm. Would something similar be going on on the AVR too?

I do not know anything about Class D, and very little about solid state amplification, so I am not the right person to ask or comment.

Jeff

 

[Kevano]

I will be glad to know the driver CMS ( equivalent compliance) and MMS ( Moving mass). IME, only drivers with high compliance and low MMS work well in sealed enclosure

Is Cms 0.87 mm/N high enough and is Mms 2.4 g low enough for a sealed enclosure? I went by the Qts rule of Qts between 0.4-0.7 for sealed enclosure. Driver Qts 0.66.

 

[Hari Iyer]

Is Cms 0.87 mm/N high enough and is Mms 2.4 g low enough for a sealed enclosure? I went by the Qts rule of Qts between 0.4-0.7 for sealed enclosure. Driver Qts 0.66.

Thanks for details, Imo 0.87 is medium compliance. I would prefer around 1.3mm/N for more damping material to be added. In your case only medium damping should be ok. 2.4g is very low and nice.

 

[Kevano]

Did you try modeling the box in the Leonard Audio TL software. It will show you how much you need to stuff.

I finally managed to read the TL-Userguide.pdf yesterday. Started modelling the box. Worked out 0.95 lbs/cubic ft for the 2.16 lt box.

Keith, can you please check this. I have attached the project and driver file.

 

[Kevano]

@keith_correa Can you please check this.

 

[keith_correa]

Does not need a big box. 1.2 liters with 0.75 lb/cu.ft.

 

[Kevano]

Does not need a big box. 1.2 liters with 0.75 lb/cu.ft.

Thanks for his Keith an more importantly for introducing me to Leonard Audio TL software.