Thx BP1, hadn't caught on to that yet.
I've always found Helmholtz with the Loudspeaker Wizard, looking at the Chamber.
The HR 55.20 version I'm using shows Helmholtz when cursor is on Ap.
On Lpt, cursor gives 'Port tube air mass', and "End correction" in cm. What is end correction?
Hey Art, Here's an impedance sweep.
I'd call it about 24-26Hz minima.
A little roughness in the trace at the bottom, no doubt due to the bracing I tried to get in as close to the port to help with back wall stiffness, hopefully without affecting port flow too much.
Time to stress her and find out.
The port is built like a tank. Separate drop in assy that weighs almost 23 lbs.
I've become half-convinced a lot of port noise we attribute to high velocity air flow / chuffing, may well be just the damn thing resonating/rattling at high SPL.
Plus the port assy helped with bracing...I've never tried to brace one near this well before.
My fault guy. I just noticed that I made a mistake in the tune location while modeling the RCF LN19S400 in MULTIPLE BR enclosure for another thread. I hate that HR is not a mobile app. It's easy to forget exactly where something is located in the program when you are on your phone.
I'm trying to get the Particle Velocity function to work for a simple BR enclosure and NONE of the various types models will unlock the feature. I am trying to show that 1/3 of driver(s) total Sd is the guideline you should use for the smallest diameter port/positive flare throat/negative flare mouth to prevent port noise or high air speeds.
I'm trying to get the Particle Velocity function to work for a simple BR enclosure and NONE of the various types models will unlock the feature. I am trying to show that 1/3 of driver(s) total Sd is the guideline you should use for the smallest diameter port/positive flare throat/negative flare mouth to prevent port noise or high air speeds.
Regarding end correction, check out this thread.
https://www.diyaudio.com/community/...sonance-absorbers-and-port-geometries.388264/
https://www.diyaudio.com/community/...sonance-absorbers-and-port-geometries.388264/
Thx for that.
I've finished one the subs, will post a thread on it shortly.
Actually you hover over the Lrc ,Vrc or Ap field but not the Lpt field
Lpt gives you the below
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I know. I was on my phone when I typed it. I knew it was either Ap or Lpt. LOGIC made me think it was the Length of the PorT since you determine the diameter of the port 1st then the length to get to the frequency number. This situation is another reason why I wish HR was an app.Actually you hover over the Lrc ,Vrc or Ap field but not the Lpt field
Lpt gives you the below
View attachment 1288258
Mark,
love your design, @368L the Tuning shift to 30Hz
i picture a cluster of those instead of the normal double 18 like the KS28's
did you made a sketch of it on cad or sketchup ?
you have super wood chops!
Thanks maxolini !
I don't have a good sketch, but i can post some build picts and info that might help detail it some.
Will, do it now in the other thread....sorry for the two thread BS....won't let that happen again.
(and mods, pls feel free to merge threads is such is possible/warrants doing so..)
Sorry, when you said I have good wood chops, i thought that meant you had seen the sub in my "V-Twin" thread..
here's the post in it I was making to reply to you...
https://www.diyaudio.com/community/threads/v-twin-double-18-bass-reflex-build.410229/#post-7635979
Sorry again...kick my butt for 2 threads...
here's the post in it I was making to reply to you...
https://www.diyaudio.com/community/threads/v-twin-double-18-bass-reflex-build.410229/#post-7635979
Sorry again...kick my butt for 2 threads...