My long tapped horns are only 105dB/W corner loaded.
Work fine for hifi.
Would need lots of power or lots of them at bigger venues.
They don't sound that great above 60Hz. It's there and defined but not that punchy.
The Lab12 TH sub I made recently sees about 108dB.
I had 118dB or a bit more out of it on test.
55Hz and up I find the SH50 style cabs with twin 12" (part horn listed mostly reflex), work really well with punchy kick and nicely defined bass lines.
I'm really happy with the combination.
Work fine for hifi.
Would need lots of power or lots of them at bigger venues.
They don't sound that great above 60Hz. It's there and defined but not that punchy.
The Lab12 TH sub I made recently sees about 108dB.
I had 118dB or a bit more out of it on test.
55Hz and up I find the SH50 style cabs with twin 12" (part horn listed mostly reflex), work really well with punchy kick and nicely defined bass lines.
I'm really happy with the combination.
BANDPASS (BPH, FLH, TH, BP6S, BP6P, BP4) RULES!!!
https://data-bass.com/#/systems?sort=100Hz:1,mfr:-1,name:-1&activetab=max_output&_k=0kg6is
https://data-bass.com/#/systems?sort=100Hz:1,mfr:-1,name:-1&activetab=max_output&_k=0kg6is
That same document was addressed in another recent thread.
I'm cheap labor, got many drivers, lots of space, and built a BP4 (FLH with a straight port). Bandpass Rule!
I'm cheap labor, got many drivers, lots of space, and built a BP4 (FLH with a straight port). Bandpass Rule!
@BP1Fanatic: The middle sub drivers are way too close together if they have a pole core bore and fighting against each other, that means you have effectively halved the physical distance between them. And since the distance between them looks like it's just a tad more as the thickness of the boards (looks like 5cm at best), that would be equal to have the pole core bore around ~2-3 cm from a enclosure wall. That doesn't matter much on low level but you wouldn't have used 4 isobaric pairs if you wanted low level. With higher level the cooling is a lot worse and the inner drivers having no air exchange anyway, it's going to be a lot worse. But that's not all, with the power compression on these drivers starting a lot earlier than the outer ones (because, you know, cooling), the isobaric principle doesn't work very well anymore, the heat increase the resistance of the VCs, effectively shifting to a higher Qts and distortion increases a lot sooner than needed.
It's not very difficult to fix that. It looks like you have a few cm between the subwoofer and the back of the car. If you extend the enclosure just by the thickness of the wall and mount one side of the drivers with a offset, then that very small offset will already help immensely. It's not perfect but it gives you more headroom and it lets the inner drivers live a lot longer.
It would also reduce the vibrations if you'd add a short 2x4 between the bottom and the top ("ground to ceiling) of the enclosure in the middle of the sub, since that's by far the biggest unsupported surface.
@IamJF: Sorry, didn't mean to hijack your thread.
It's not very difficult to fix that. It looks like you have a few cm between the subwoofer and the back of the car. If you extend the enclosure just by the thickness of the wall and mount one side of the drivers with a offset, then that very small offset will already help immensely. It's not perfect but it gives you more headroom and it lets the inner drivers live a lot longer.
It would also reduce the vibrations if you'd add a short 2x4 between the bottom and the top ("ground to ceiling) of the enclosure in the middle of the sub, since that's by far the biggest unsupported surface.
@IamJF: Sorry, didn't mean to hijack your thread.
I see what you mean. If they blow, then they were only $30 a piece.
That's another thing I hate about sealed enclosures, no venting of the voicecoil.
I always design my BP4's with the speaker basket in the vented section. Obviously, with an isobaric setup, that's not possible for all the drivers.
That's another thing I hate about sealed enclosures, no venting of the voicecoil.
I always design my BP4's with the speaker basket in the vented section. Obviously, with an isobaric setup, that's not possible for all the drivers.
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Curious how FLH transient response is affected by only increasing mouth surface area alone ie. stacking cabs. If it doesn't supposedly do much if anything to increase gain, you'd think it wouldn't hurt anything else.
I only tried adding more FLH enclosures without extra tuning. The LF got louder but also sounded fuller towards the bottom with more extension.
I only tried adding more FLH enclosures without extra tuning. The LF got louder but also sounded fuller towards the bottom with more extension.
Four 2pi cabs = one 0.5pi cab.
Not only do you get 0.5pi in a car, but you get transfer function (cabin gain) too.
I forgot to mention, I'm not using the full power of the amplifier. The series parallel parallel wiring is 2 ohm where the amp is 1 ohm stable.
Not only do you get 0.5pi in a car, but you get transfer function (cabin gain) too.
I forgot to mention, I'm not using the full power of the amplifier. The series parallel parallel wiring is 2 ohm where the amp is 1 ohm stable.
here are some sims and design thread for horn loaded sub. Maybe you find something interesting.
https://www.diyaudio.com/community/...rol-bc-subwoofer-bc218-2-design.413237/page-3
https://www.diyaudio.com/community/...rol-bc-subwoofer-bc218-2-design.413237/page-3
A little late, but - comparison of two tapped horns and one bassreflex (with sufficient sized port), with identical tuning, with the same speaker, and a closed box.
Sensitivity, impedance, phase / group delay, and distortion limited Max. SPL measured.
➡ Tapped Horn vs. Bassreflex vs. Closed Box - messtechnische Aufarbeitung
THANK YOU for these measurements!
I'm still not sure if I would call something like the THAM15 a horn ... it's a resonator as you see with the notches and peaks very close to the usable bandwidth.
There is a significant gain with the horn - but it's 266L for a single 15". You could fit 3 ported 15" in that volume!
A double 15" will have about the same max SPL with the need of more amp power and driver costs but way simpler woodwork and less space/more flexible setup.
So it's about what we expected. And why horn subs get less and less in times of cheap amp power.
I'm still not sure if I would call something like the THAM15 a horn ... it's a resonator as you see with the notches and peaks very close to the usable bandwidth.
There is a significant gain with the horn - but it's 266L for a single 15". You could fit 3 ported 15" in that volume!
A double 15" will have about the same max SPL with the need of more amp power and driver costs but way simpler woodwork and less space/more flexible setup.
So it's about what we expected. And why horn subs get less and less in times of cheap amp power.
Why?
The speaker just unloads faster and transient is worse. Tuned high at 42 Hz
Fs is 32 Hz for that driver.
A driver with .3 Qts has very good control, but the low end response will gently curve downwards in a simulation transfer function.
Tuned at 42 Hz, transient would be garbage below 55 Hz.
With high Qts you can tune below Fs of the driver.
Problem is people dont like the gentle roll off.
But in reality, the sim is nonsense.
Real life everything it a assisted alignment, EQ is added.
You tune below Fs so transient is not garbage, bass notes are real cone movement.
And when you boost EQ it is still real cone movement.
Since the magnet is powerful, real cone movement has good control.
People need to look at cone movement, not their " F3" in sim.
Who cares, when you F3 is a unloading port with no accuracy.
And above that is port, not cone movement.
They are all assisted alignments, F3 is whatever you want it to be.
Thing is, is it all fake port and poor transient,
or is it actual boosted bass with cone movement with a strong magnet controlling it.
Did you ever designed and used ported PA woofers?
For a 34Hz tuning this driver would need way more volume. But you would likely get a peaky and resonant response.
At the given volume 34Hz only give very little gain and extremely little cone movement reduction. We are talking live music - we need power at 60Hz and stuff below 40Hz is mostly unwanted. And we NEED that SPL gain from the port for PA!
What you describe is nice in theory - but not what we need for a PA Sub. It needs to be small and light and loud. And sound better as the stuff you can buy, otherwise I would not build it 😉
p.s.: Can you show me one ported PA sub which has it's port frequency below the resonance frequency of the driver?
The EAW SB1001 has an Fb of 30Hz, and likely uses drivers with 32Hz Fs.
There are many live music engineers that would disagree that "stuff below 40Hz is mostly unwanted", so they choose cabinets with Fb below 40Hz.
Wow - that's actually a believable manufacturer measurement - nice! There are a few modern ported subs with very low tunings, sensitivity goes down and you need plenty of them. This is done when money & space is not the main concern - and for sure sounds great!
The EAW SB1001 has an Fb of 30Hz, and likely uses drivers with 32Hz Fs.
There are many live music engineers that would disagree that "stuff below 40Hz is mostly unwanted", so they choose cabinets with Fb below 40Hz.
Which Instrument has significant Level below 40Hz? You can downtune bass/guitar to C or lower and use that artistically ... that's why I wrote mostly, you can construct cases where it's needed. When I look at my mixer at a live gig ... there are 1-2 channels without low cut, sometimes it's on all channels (e.g. muddy bass).
An yes, there is music out there which benefits from lower bass. But in maybe 95% of cases you are fine with 40Hz. And often I would have been happy when I would have gotten 40Hz from the house PA ...
Just sharing my opinion about how important is for subwoofers to play content below 40Hz, it may go against some beliefs commonly accepted and you might disagree.
One must realize often not only ''real instruments'' sounds are meant to be played from subwoofers (even tho some real instruments go below 40hz). I look at speakers in general more like devices that convert electrical signal in acoustic energy - so do not really design them with having specific instruments frequency response in mind. I take it more as sheer ability to reproduce input signal with good SPL, efficiency, ... And they have to be acceptable size/weight ofc.
I do still spend a bit of time analyzing different recordings to see how much content below 40Hz is used, I believe minimum for most modern music is about 35Hz, flat to 30Hz is optimum if space/weight is not an issue.
Also do not really agree with term muddy bass, I believe this ''muddy bass'' is often quite a bit higher in frequency than 40Hz, or even above 100Hz actually. It is not a well defined term and also overall cabinet design has huge impact on how loud/clean/accurate bass is percieved. Frequencies below 40Hz are most often not really heard, but felt and if distortion is reasonably low those frequencies should not cause negative impact on overall mix balance or muddines. I think of it as ''special effect'' thing that just adds something to entire mix and is not necesarry but changes how music feels when present.
It is also important for subs to be set up properly and aligned with main speakers. Many many times I have seen setups that made exceptional subs sound bad because of this mistake. Acoustical crossover, slopes, time alignment, and lack of additional EQ to shape the sound according to the genre. Not cutting ''mud'' below 40Hz as you adress it is actually minimal ''problem'' compared to those I mentioned. And even in live music I do not understand why someone would not want any output below 40Hz.
One must realize often not only ''real instruments'' sounds are meant to be played from subwoofers (even tho some real instruments go below 40hz). I look at speakers in general more like devices that convert electrical signal in acoustic energy - so do not really design them with having specific instruments frequency response in mind. I take it more as sheer ability to reproduce input signal with good SPL, efficiency, ... And they have to be acceptable size/weight ofc.
I do still spend a bit of time analyzing different recordings to see how much content below 40Hz is used, I believe minimum for most modern music is about 35Hz, flat to 30Hz is optimum if space/weight is not an issue.
Also do not really agree with term muddy bass, I believe this ''muddy bass'' is often quite a bit higher in frequency than 40Hz, or even above 100Hz actually. It is not a well defined term and also overall cabinet design has huge impact on how loud/clean/accurate bass is percieved. Frequencies below 40Hz are most often not really heard, but felt and if distortion is reasonably low those frequencies should not cause negative impact on overall mix balance or muddines. I think of it as ''special effect'' thing that just adds something to entire mix and is not necesarry but changes how music feels when present.
It is also important for subs to be set up properly and aligned with main speakers. Many many times I have seen setups that made exceptional subs sound bad because of this mistake. Acoustical crossover, slopes, time alignment, and lack of additional EQ to shape the sound according to the genre. Not cutting ''mud'' below 40Hz as you adress it is actually minimal ''problem'' compared to those I mentioned. And even in live music I do not understand why someone would not want any output below 40Hz.
Is the same unit used in both cases?
What is the internal volume of the horn? For a fair comparison, it should be 130L too.