is it each fold in a transmissionline as you would (could) stack (2 if entering from the closed end) ,
or 3, if entering at the (~0.349 for the 3 x 1/4 notch/cancel) ? and have the driver (direct radiator) in the same exact spot (if concentric) as the vent.
also??
do you get ‘gain’ from the superposition of freqs that didn’t quite ‘make it past’the 180 degree deliberate turn? because they are similar in ‘sine wave size/shape’ so they promote output of similar input outgoing ‘size/shape’?
ignoring all of the super details and losses etc.??
(hope i worded this correctly?)
or 3, if entering at the (~0.349 for the 3 x 1/4 notch/cancel) ? and have the driver (direct radiator) in the same exact spot (if concentric) as the vent.
also??
do you get ‘gain’ from the superposition of freqs that didn’t quite ‘make it past’the 180 degree deliberate turn? because they are similar in ‘sine wave size/shape’ so they promote output of similar input outgoing ‘size/shape’?
ignoring all of the super details and losses etc.??
(hope i worded this correctly?)
This is an example of a regular acoustic low pass filter. It is likely to have a modal influence in the transition region...
Last edited:
I really need an electrical background at this point because I’m so far in the stuff I can’t describe fairly or even put questions together with the right jargon..
I am building things way over my head that he seems like a remarkably interesting but difficult to describe?
I am building things way over my head that he seems like a remarkably interesting but difficult to describe?
Before you even start trying to do the math. Understand how it works and affects your direct radiator and response.
Download Hornresp, Leonard audio transmission line software etc. and play around with it, placement of radiator along the length effects the lines behavior.
The 180 degree turn is often small and almost irrelevant compared to the frequencies in question. the output is 90 degree out of phase just as a Bass relex, a tall Bass Reflex enclosure that is small in width and depth in comparison (not unusual in today's commercial speakers) becomes a Transmission line if sufficiently long to excite it's eigenmode /pipe resonance., and where the crossing line between TL and BR is, can at time be blurry.
http://www.quarter-wave.com/index.html
a good intro to hornresp.
https://www.diyaudio.com/community/threads/an-improved-transmission-line-alignment.243483/
yes, my questions are based on this exactly as you can see👍🏻 But they remain questions answered but create more questions… it’s absolutely amazing(here’s two parallel ‘TL’ with the same exit (240 cm and 80 cm with driver entry @ 20 cm each(the center of 4 “ driver pairs )
Attachments
Last edited:
Martin King hookup/suggestion when i was poking him with ‘multiple resonators’ all over both sides of the cone whilehe was sneaking/exploring in a bass reflex to a tl instead .
Attachments
what could we ‘assume’ ? are there 2 low pass filters here?
hard to discern between a singie fold and 2 fold (but never compared perfect apples to apples necessarily … (same driver, same everything otherwise and its always about that 3 x 1/4 harmonic at that point (2 fold offset entry)
hard to discern between a singie fold and 2 fold (but never compared perfect apples to apples necessarily … (same driver, same everything otherwise and its always about that 3 x 1/4 harmonic at that point (2 fold offset entry)
Attachments
Last edited:
Well, the way I view it based on the muffler description/IME it's always the backside/terminus chamber since it's in series with the output; the fact that it's tapped doesn't somehow move it elsewhere.
The 'tap' in this case can viewed as a band stop filter if you visualize the driver mounted to its closed end, so while normally it creates a deep null, when physically delayed a 180 degrees it becomes a peak, i.e. 'tapped', so of course can become a wider/narrower BW depending on amount of delay as BP6S design theory proves.
The 'tap' in this case can viewed as a band stop filter if you visualize the driver mounted to its closed end, so while normally it creates a deep null, when physically delayed a 180 degrees it becomes a peak, i.e. 'tapped', so of course can become a wider/narrower BW depending on amount of delay as BP6S design theory proves.
this all makes sense and can be viewed in HR (and seen in ‘most’ of my RTA stuff too where it gets hard to keep track)👍🏻👍🏻
green (first pic green trace )
red(white trace )
blue(last pic green)
driver positions kicked my butt recently using a moveable baffle for a bit
until leaks started becoming excessive from the gaskets getting flattened and pinched, etc and then permanently sealed it into ‘green’ (best) forever
Attachments
Last edited: