For Vas, I use metal or ceramic bowls, they are very sturdy, very easy to measure internal volumes and the hemisphere shape is ideal as an enclosure. I stick a sponge between the bowl and the speaker and is very easy to secure any speaker with scotch tape. I used this method up to 12 inch speakers.
In olden days, some people used large open cardioid baffles, the cardioid shape has a nice even responses being either equally good, or equally bad across the board. It does need to be rather hefty, with size also a factor, iirc the circumference would be the wavelength of the cutoff frequency of the baffle. They also look cool, like huge lilypads.
Closed-box and handheld methods are the two methods I use. Oh, and I don't build boxes for the closed box method. SWMBO has a various assortment of pots and pans in the kitchen that can quickly double as a "closed box" with the use of a suitable baffle. Some of them are actually perfect fits for the driver, no baffle required :-). Volume is easy to measure with water and a measuring cup. In any case, Vas variation of up to 20% is going to have minimal impact on speakers designed with the measured parameters anyway.
I take care measuring in room temperature (preferably close to 20deg C). Don't measure the driver straight on a table if it got a vented coil, let it breathe. Break the driver in for a few hours. In my experience, the angle of the driver measured doesn't matter that much.
That speaker holding stand looks less like a clamp and more like a guillotine, which seems like something I might need if I decided to spend that much money to test a speaker.
You need to add sufficient mass to lower the Fs by 25% or more. There is an upper limit. Don't add mass which is more than the actual moving mass of the speaker.
Thanks. Good information. Is there a need for adding the volume of cone, facing inwards the hole? You measured the box and hole. I got the DatsV3 for a my old vintage speakers. Sadly I get different VAS every time I measure and it’s way too high (120 vs 75 liter) compared to the original cabinet.
In my opinion that volume should be taken into account. But it's difficult to measure and hopefully it's small enough to not influence the measurement too much.
In DATS it compares the resonance peak between "no mass added" and "mass added". It needs to be large enough to move the Fs a certain amount (think it is 20%), depends on the driver.
I hope this channel blows up. Excellent video my man
For Vas, I use metal or ceramic bowls, they are very sturdy, very easy to measure internal volumes and the hemisphere shape is ideal as an enclosure. I stick a sponge between the bowl and the speaker and is very easy to secure any speaker with scotch tape. I used this method up to 12 inch speakers.
In REW & VituixCAD, you can also try the double mass added method. There is a paper that show that it's help for VAS precision.
can you do a video on designing and building a rear loaded horn
In olden days, some people used large open cardioid baffles, the cardioid shape has a nice even responses being either equally good, or equally bad across the board. It does need to be rather hefty, with size also a factor, iirc the circumference would be the wavelength of the cutoff frequency of the baffle. They also look cool, like huge lilypads.
Closed-box and handheld methods are the two methods I use. Oh, and I don't build boxes for the closed box method. SWMBO has a various assortment of pots and pans in the kitchen that can quickly double as a "closed box" with the use of a suitable baffle. Some of them are actually perfect fits for the driver, no baffle required :-). Volume is easy to measure with water and a measuring cup. In any case, Vas variation of up to 20% is going to have minimal impact on speakers designed with the measured parameters anyway.
Kitchen. Good idea. Thanks
I take care measuring in room temperature (preferably close to 20deg C). Don't measure the driver straight on a table if it got a vented coil, let it breathe. Break the driver in for a few hours. In my experience, the angle of the driver measured doesn't matter that much.
Great job and thank you
That speaker holding stand looks less like a clamp and more like a guillotine, which seems like something I might need if I decided to spend that much money to test a speaker.
Can i ask if you can compare with the data that the brand give us online ?
AJ: Free air measurement first, then attach the woofer it to the closed box and measure again, with the closed box option?
Great video! This approach is very useful. Just one question. What is the reccomended mass to add to the cone? Is there a limit?
You need to add sufficient mass to lower the Fs by 25% or more. There is an upper limit. Don't add mass which is more than the actual moving mass of the speaker.
@@AudioJudgement Thank you!
Thanks. Good information. Is there a need for adding the volume of cone, facing inwards the hole? You measured the box and hole. I got the DatsV3 for a my old vintage speakers. Sadly I get different VAS every time I measure and it’s way too high (120 vs 75 liter) compared to the original cabinet.
In my opinion that volume should be taken into account. But it's difficult to measure and hopefully it's small enough to not influence the measurement too much.
The DATS V2 did not agree with my S&L WT2, but my WT2 agreed with Klippel.
Heck yeah
How do yo add mass on vertical speaker? Won't it fall down?
Blu tack sticks quite nicely.
Different mass = different Vas, how much mass needs to add and why? Are you try to compare different masses and results?
In DATS it compares the resonance peak between "no mass added" and "mass added". It needs to be large enough to move the Fs a certain amount (think it is 20%), depends on the driver.
Now try the methods with an 18 inch woofer and see which ones are still viable 🙃
I don't measure my speakers - I listen to music on them.
It's great that you can hear the T/S parameters 😁
Great, So do I! Along with movies, TV shows, and video games. I also design and build loudspeakers.