Hello everyone, a while ago I had an idea that consisted of a resonant tube with 1/2 wavelength, that is, a tube with both ends open and the loudspeaker or loudspeakers would be located on the side walls.
I didn't find much content on DiyAudio about this type of resonant box, perhaps because it doesn't have many advantages compared to the well-established 1/4 wavelength resonant tube, better known as a 1/4 wavelength transmission line.
In short: anyone who has any useful content and opinion on the construction and the advantages and disadvantages of this type of resonant box is welcome.
I didn't find much content on DiyAudio about this type of resonant box, perhaps because it doesn't have many advantages compared to the well-established 1/4 wavelength resonant tube, better known as a 1/4 wavelength transmission line.
In short: anyone who has any useful content and opinion on the construction and the advantages and disadvantages of this type of resonant box is welcome.
In itself, it depends, it can be moved, but for this theoretical purpose, yes it is in the center.
Then it is the same as a single 1/4wl line. It is simply bifurcated.
Okay, I had thought about the possibility of it being just two lines of 1/4 wavelength.
But is it if it's not in the center?
But is it if it's not in the center?
It's still the same. With a driver near but not in the closed end of a 1/4wl pipe and with the far end open, you now have two paths to the open end. You have the short path straight out, and the long path back to the closed end to reflect, then out. This makes it the same.
you end up with the same thing i guess? (If) The open pipe is half as big in crossectional area but twice as long?
I wonder if there are some unique positions in the pipe that will prevent a resonance from being excited (like 1/3 from the closed end of the 1/4 wave pipe?
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D@mn, HR won't let you open up the throat in the OD function.
This is the best I could do. However, it's still a BP6P instead of a TL.
We need the blue circle to be red and the red line not to exist for an open ended TL.
This is the best I could do. However, it's still a BP6P instead of a TL.
We need the blue circle to be red and the red line not to exist for an open ended TL.
splitting the 'upstream' section of the 'TL' is possible in horn response(it kind of shows the affect?)...but i cant find a way to incorporate a seperate path for another vent?
Your 1st model is closed at both ends.
Your 2nd model still has the closed throat.
We cannot have any green or blue circles with the red circle.
Your 2nd model still has the closed throat.
We cannot have any green or blue circles with the red circle.
Yeah, The driver sits offset at 1/3 in a ‘pipe’ that has an upstream section as a single 50 cm2 x 60 cm long stub or two seperate 25cm2 x 60cm long stubs and gives you the exact same results It seems?
Almost. The length resonance will be the same. The cross resonances will be different (double in f on the divided one). However, if you split up the two parts into 90° directions each, you will get an additional length resonance wich may or may not cause peaks and cancellation. The main problem is to catch if there's a frequency within the used range in which the driver 'runs free' and easily exceeds the excursion.
Well, if the walls get too close, you'll experience high losses because of wall turbulences, so the cross area isn't the only thing to have an eye on but the dimensions too. A 4cm 'tall' line will not perform very well, even if the complete cross section is equal to the Sd.
copy the sim and mess around with it. Its unique/interesting to explore.
The closed pipe section actually has an exit/vent that is available in the ‘Ap/Lpt’ description in this unique part of the ‘OD’ and ‘Od1’ sections .
a couple of different stub locations can be created and the rabbit hole is deep 😝. You can describe a ‘paraflex’ without the motor in the other resonatur and strange things to study/ponder