i've tried to sim the peavey 18" lowrider and it looked pretty similar to the P Audio CB18-650EL. course i am just learning hornresp and there is a good chance i have no idea what i am looking at. however, best way to learn is to do it......now in the states, the P Audio driver is on sale for $156 (overstock item), the peavey 18" lowrider can be had for $184.
Look at the group delay response in HornResp and you'll see the difference and I can assure you the impulse behaviour in reality is another issue.
i'm getting ready to head out for the evening. i will have some questions for you tomorrow i'm sure. i have the CNC programs written to cut out the uprights for the TH-18. just gotta get the guy that operates the machine to run my programs.
Jim,
I don't know what makes you hmmm????😀
The Apache, SS15, Fury sub all have similarities to the DSL TH-115/118 which they all emulate to some degree.
Martin's plan happens to be even more similar to the DSL TH-115/118 .
My BC18SW125-4 loaded (like the current TH-118) Keystone uses a different fold pattern entirely, but similar path length and cabinet volume, and has very similar frequency and phase response to the DSL TH-118.
I had hoped that would happen 😉.
Art
I don’t get a lot of time to keep up with this thread - and this thread is taking up a lot of my time... Never less I still consider this design as work in progress, and I sure that it could be improved on.🙂
At the moment I am considering the bracing of the cabinet.
It would be nice to be able to use the spare material from the cut sheets to brace the cabinet. I am a little unsure how using 18mm wide material would affect the performance of the speaker.
It occurred to me that the bracing should be angled to the horn path within the speaker to reduce the cross sectional area reduction at any given point.
Also I have tried to connect the strongest points of the speaker to the weakest points.
Is this bracing to thin for the material? The ribs as shown are 18 x 30 typically.
I will probably add some more bracing yet – but thought I would post this for some feedback
Regards
Martin
At the moment I am considering the bracing of the cabinet.
It would be nice to be able to use the spare material from the cut sheets to brace the cabinet. I am a little unsure how using 18mm wide material would affect the performance of the speaker.
It occurred to me that the bracing should be angled to the horn path within the speaker to reduce the cross sectional area reduction at any given point.
Also I have tried to connect the strongest points of the speaker to the weakest points.
Is this bracing to thin for the material? The ribs as shown are 18 x 30 typically.
I will probably add some more bracing yet – but thought I would post this for some feedback
Regards
Martin
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Your proposed bracing is more than adequate, cut off strips in triangles are very effective.
Martin, with bracing you have 3 different issues;
Suppression of resonances in the panels (can be achieved with relative thin braces).
Suppression of deformation of panels under the pressure of large and intensive sound waves (needs much stronger braces such like the bottom brace).
Structural reinforcements to make the cab resistant to (extreme) external forces from accidental drops and transport. For example small square braces behind the wheel attachments are no luxury, I think.
But somehow I believe you can teach us more about structural reinforcements and how panel thickness works in relation to brace thickness and their position to endure forces from all sides 😉. The enlarging of the first brace section to 81mm is roughly based on its angle and the total surface of the bottom panel. Oh, I made a small correction (suggestion) in the back where the braces are 'attached' to their vertical brace.
I know the force from the front brace at the bottom is the extension of it in your suggestion but I'm worried more about the back panel to be honest. Wondering if you can model all these things more precisely, if you ever find the time to do these things…
Suppression of resonances in the panels (can be achieved with relative thin braces).
Suppression of deformation of panels under the pressure of large and intensive sound waves (needs much stronger braces such like the bottom brace).
Structural reinforcements to make the cab resistant to (extreme) external forces from accidental drops and transport. For example small square braces behind the wheel attachments are no luxury, I think.
But somehow I believe you can teach us more about structural reinforcements and how panel thickness works in relation to brace thickness and their position to endure forces from all sides 😉. The enlarging of the first brace section to 81mm is roughly based on its angle and the total surface of the bottom panel. Oh, I made a small correction (suggestion) in the back where the braces are 'attached' to their vertical brace.
I know the force from the front brace at the bottom is the extension of it in your suggestion but I'm worried more about the back panel to be honest. Wondering if you can model all these things more precisely, if you ever find the time to do these things…
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I like all the ideas and effort put into this design! I have been busy with work and doing motor swaps so I haven't had spare time to grab the wood and start building theses. Soon soon 🙂
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You can find the answer about the power compression in post #24 in the thread:C/E/X PA Flat to 30 (FT30) PA TH Awesomeness. If there are doubts about the Thiele-Small data I used for calculating Xmax [(Hvc-Hg) : 2]use this link
Ah, that part of the reply. Yes, you did calculate that - my apologies. I kinda just copied and pasted what data requests you asked for a few pages back. It would also be cool to see how the manufacturer's numbers match up. So, distortion data may still be good to have...and does anyone know if there are any differences between the 8 ohm and 4 ohm versions of the 18SW115, besides resistance 😉 ? Would be nice to use the 4 ohm versions =)
Not sure which driver is optimal (8 ohm or 4)... I'm away from the laptop, on my phone, at the moment 😉 I'll have a look when I get back.
Both should be working in the Xoc1 fine although there could be a small difference in Group Delay. I haven't seen any PDF about the 4 ohm version but I'm working on it. Maybe Art has the Thiele-Small for the 4Ohm version since he uses them.
I already have 12 Nos. of 3015LF in dual 15 ported cabs. They are good but not great. I could easily use these in the SS15 but I want them to go a little lower.
Already have 3 Nos. QSC4050HD amps and one more is on the way. 2 Nos. 5050 are part of the existent setup. 5050 is not as good for LF as they are for Mid frequencies. Hence, the idea is to run the 4050s bridged mode for each 18NLW9600(c) loaded TH18. 4 cabs should be sufficient for most mid to big sizw events. Ideally, I would like to get the sound that 6 Labsubs could put out, but then the weight, size and constraints of stage size/setup etc., would make me choose the TH18; I am not sure if 6 TH18s would come close to the ideal I am dreaming of?
I'm not sure I've never heard a lab sub.
But the event I went to the other day had 4 stacks of speakers around the "dance floor" (this was an outdoor event in a parking lot) Each stack had (4) Martin audio ws218x subwoofers (2 18's per cabinet) So (32) 18's total with some serious power....needless to say the bass was pretty ridiculous! 😀
Anyone want to model this TC sounds pro 5100?
TC Sounds Pro 5100 18" Neo Subwoofer Driver
xmax is kind of nutty at 31mm
But the event I went to the other day had 4 stacks of speakers around the "dance floor" (this was an outdoor event in a parking lot) Each stack had (4) Martin audio ws218x subwoofers (2 18's per cabinet) So (32) 18's total with some serious power....needless to say the bass was pretty ridiculous! 😀
Anyone want to model this TC sounds pro 5100?
TC Sounds Pro 5100 18" Neo Subwoofer Driver
xmax is kind of nutty at 31mm
I already have, but didn't post it since the output didn't match up w/the dollars that driver costs 😛 Response did look good tho. I'll post it from my other (PC) laptop in a moment.
Left: 18Sound 18LW2400 vs Pro 5100 (SPL)
Center: B&C 18SW115 vs Pro 5100 (SPL)
Right: B&C 18SW115 vs Pro 5100 (Group Delay)
(In Hornresp, the Pro 5100 reaches its AES power rating of 1000W way before xmax)
Center: B&C 18SW115 vs Pro 5100 (SPL)
Right: B&C 18SW115 vs Pro 5100 (Group Delay)
(In Hornresp, the Pro 5100 reaches its AES power rating of 1000W way before xmax)
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