Hi yall, I'm hoping to create a space to talk about subwoofers that reach higher than typically expected, all the while covering down 20hz/30hz without sacrificing the accuracy of its upper passband. Sealed enclosures with multiple large woofers, and high xmax are a good choice. Having pairs of these types of subs only makes things better and being that we are traveling into the realm of localization by playing so high, these types of subs are to be apart of the mains, either by proximity or appendage.
Sealed enclosures as described above make short work of the task... I'd consider something like a large sealed cab, dual 18" with >14mm xmax the status quo. Where it gets interesting is transmission line and bass reflex. Vented Designs need to be a lot more particular. Damping is needed but maybe not in every design. A front loaded horn like the known HT tuba which is an bandpass design where the front horn is entered in offset, may do well thanks to the near 0 CSA at the beginning of the line. Of course it comes with its own sets of pros and cons, the line length creates delay, for example.
I will post some designs that fit the category, and I hope that you guys have some designs that you like as well. There are details that help optimize these types of subs, lets chop it up at our leisure
Sealed enclosures as described above make short work of the task... I'd consider something like a large sealed cab, dual 18" with >14mm xmax the status quo. Where it gets interesting is transmission line and bass reflex. Vented Designs need to be a lot more particular. Damping is needed but maybe not in every design. A front loaded horn like the known HT tuba which is an bandpass design where the front horn is entered in offset, may do well thanks to the near 0 CSA at the beginning of the line. Of course it comes with its own sets of pros and cons, the line length creates delay, for example.
I will post some designs that fit the category, and I hope that you guys have some designs that you like as well. There are details that help optimize these types of subs, lets chop it up at our leisure
Dayton RSS390hf in 3cuft sealed with EQ and lots of power can do this……you’ll need two per side. I’d suggest each in its own cab stacked……keeps the weight manageable and enclosure panels short to reduce resonance. While I appreciate the massive displacement of 18” drivers, they’re just so unmanageable and xmax is generally short except for high power Faital Pros at $900 per driver.
Nah, just brace the living crap out of it and you'll be totally fine.
Keep an eye on the internal dimensions btw. If you want to play all the way up to about 200Hz.
With an internal size of about 50cm, the first harmonic of the standing wave is about f=344/(2*0.5)=344Hz (without correction).
So you don't want to go much larger or you have to come up with some tricks.
Or lower that upper frequency range.
Keep an eye on the internal dimensions btw. If you want to play all the way up to about 200Hz.
With an internal size of about 50cm, the first harmonic of the standing wave is about f=344/(2*0.5)=344Hz (without correction).
So you don't want to go much larger or you have to come up with some tricks.
Or lower that upper frequency range.
For the Offset TL sim'd above, That works out about right for a ~30inch wide enclosure. Sadly one cannot place 2 woofers one space to create the FR picture, unless side by side I guess. A peak Eq could take care of that peak, as a single woofer enclosure.
This offset thing intrigues me because its the only way to get a response this clean without using damping material, which eats efficiency.
Absolutely the best state to be in. The baby cot is fast filling up with drivers and circuit boards, the baby only slept in it once
The alternative is very sad. Many biz models are becoming irrelevant and failing. When our Taxi industry got ubbered, it was a miserable couple of years just reading all the projects you folks are doing and pining to afford just one lil bit of audio distraction
Re high output, I have been talking to tech a DS18 tech about a very high output flat to 20hz system. Their recommended driver starts at 10" for 20hz and goes up to a 15" size and not too far off the JL W7 series. It is a very promising range if one is interested in a high output low reaching home sub. The series is the ZXI
I only intend to have one system, and it ain't small lol. The sacrifice is for the sake of Accuracy but honestly taking up and area that is 32x32 is not much of a sacrifice. People placing their loudspeakers that might be 15x15 or maybe 10x15, and still have 32x32 empty space around that loudspeaker.
That doesn't answer my question, I'm asking how to recreate this: https://www.diyaudio.com/community/attachments/1713153313957-png.1299041/
S1 S2 S3 S4 are points along the main body Those numbers are cross sectional areas in cm2. Convert that into inches squared if need be. L12 L23 L34 are lengths in between/along each point in cm.
Technically this might be called an offset mass loaded transmission line. The woofer is offset in way that the reflections from one of the line, line up harmonically, and the end result is a smooth FR versus the harmonica cancellation normally seen in some TL designs before damping material. The unwanted side effect is the larger than normal spike in Group Delay at the tuning note. By placing resonance deep enough I think the negative outcome is mitigated. An even deeper tuning might be warranted and by increasing the length of the main body you can drive the resonance down but size starts to get even bigger, so you might want to decrease CSA. Honestly it'd be nice to get GD down to 10ms by 30hz and let the rest fall where it may.
I am intrigued in this enclosure approach but I am scared to build it without more knowledge. For example if I build it like this below... will the FR result the same? I don't know. Then theres a matter of how to get eh port to the front. @GM
Yeah but the only way to keep the Fr is to place each driver at the same point along the line?, thus side by side? Or do can you place them symmetrically using the center point as the mid point between the two drivers?
@Rademakers this was wrong, sorry about that, You can start from scratch by creating an transmission line, and choosing the mass loaded option. I know you are more interested in the construction of such but this will help you play with dimensions so you can get your desired final volume.
Well that makes it a lot easier. I didn't know such a thing was possible lol.... Can you explain how to tell when BR ends and TL begins? So basically these guys are acoustical identical.... I guess I should be able to tell by now but tapering and mass loading blur the line for me.
I prefer front ports, what do I need to do?
I prefer front ports, what do I need to do?
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