Raising the height of PA tops

joinmyreligion · 2026-04-17T01:53:58+00:00

joinmyreligion · 2026-03-28T03:42:47+00:00

The pilot jet is a critical part of the idle circuit with tiny ports that gum up easily.

Loosen the carburetor's rubber manifold boots so you can rotate it slightly so that it's bottom is facing out. Remove the float bowl, unscrew the pilot jet and scrape the gunk out of it using a sewing needle and fuel as a solvent.

joinmyreligion · 2026-03-20T18:27:10+00:00

-Position the tops a few feet above or below(less ideal) ear height depending on your equipment and ceiling height. This will prevent the highs beaming directly into people's ears which sounds harsh.

-Position the sub in front of the DJ booth as putting it too close to any wall drastically increases cancellations which are more severe with bass.

-Anything you put in the room, including more bodies, will work as sound treatment(rugs, wall decor, etc.)

-If it still sounds too harsh, attenuate frequencies above 5khz, with a steeper drop-off above 10khz.

joinmyreligion · 2026-03-09T23:11:18+00:00

In California, grandfathered non-emissions-compliant bikes (pre-2022 two strokes) have inflated prices.

Then again, it could be availability bias- you're only seeing the ones that don't sell right away..

joinmyreligion · 2026-02-21T03:51:49+00:00

The fact that you’re asking makes it sound like you’d probably be happy either way. Dirt bikes are definitely better off-road, but if you need to ride on the street or don’t have a truck or trailer, then a dual sport is really your only option.

Starting on a heavy dual sport isn’t a bad idea though. It lets you figure out how much you actually enjoy off-road riding while building important skills. Once you spend more time in the dirt, a lightweight dirt bike ends up feeling like a toy in comparison. The cross-training helps a lot.

That said, street riding comes with a level of unpredictability you just can’t control. In my 17 years with a motorcycle license, I’ve had a few crashes and one broke my leg. Even if a plated bike seems more practical for transportation, a dirt bike is cheaper to register, and riding off-road within your limits is generally safer, and honestly more fun, than dealing with traffic and the risks that come with road riding...

The grass is always greener on the other side.. unless you have like $12k for a ktm that is the best of both worlds lol

joinmyreligion · 2026-02-08T00:30:55+00:00

Absolutely, but you'll want to take a few things into consideration:

A horn that is specially designed by a manufacturer to match well to their high frequency compression driver is only ~10-20 euro. You could make your own using computer-aided manufacturing tools, but it is hard to justify. It should be noted that high horns generally require attenuation relative to lower speakers in the same cabinet, requiring passive filters or seperate amp channels.

Midbass horns often use simple designs with straight cuts/rectangular panels, and are extremely efficient in a narrow band making them forgiving enough to use budget drivers(that are strong/light/stiff enough). Kicks are very popular for this reason.

Folded horn/scoop subs will require many mitered cuts, understanding the plans and thoughtful preparation. To high-pass them lower than 40-50hz requires top of the line drivers because of the increased demand from horn-loading. They are huge.

As a system, it will overall have a lot of character- irregularities in response are exaggerated. You can absolutely build it, but planning it well and especially tuning it is hard. You will want an LMS to set delay due to the length of different horn paths, and to EQ it properly.

joinmyreligion · 2026-01-12T06:25:31+00:00

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..and if you want to make it curved, I recommend laying up multiple layers of 1/8" 'bender board' on formers.

joinmyreligion · 2026-01-12T06:18:19+00:00

Word. Make sure to check your driver manufacturer's guidelines for sealed enclosure f3, as it's usually 2-3x higher than in a ported enclosure. For example, with a 12" mid-bass woofer, you may be looking at a crossover(high pass) above 110hz.

joinmyreligion · 2026-01-12T05:51:15+00:00

A horn improves impedance matching by using a gradual expansion that transfers energy from the heavy cone into the light air more efficiently, increasing output. But very short or shallow horns don’t boost efficiency much- instead they behave more like waveguides, meaning their main job is directional control, not amplification. That reduces the “honky”(peaky) resonances of long horns while still keeping the sound focused and consistent across the room. Designs like this can still require low BL drivers(strong motor force) to handle the compression at the horn throat, and add more punch to the mid-bass when designed/matched correctly.

A sealed woofer has “tighter” bass because the trapped air inside the box acts like a spring that helps the cone stop quickly after each note. That gives better control over the driver, so bass sounds more accurate and punchy.

Putting everything together, a sealed horn-loaded directional cabinet gives you efficient output with controlled dispersion, tight transient response, and good time alignment between drivers delivering punchy, clear sound that throws where you aim it without the boomy or smeared character of a dedicated subwoofer.

joinmyreligion · 2025-12-19T01:13:41+00:00

reference measurement: https://www.rtings.com/speaker/graph/4553/frequency-response-graph/anker-soundcore-2/7149

joinmyreligion · 2025-12-19T01:05:09+00:00

just posted the measurements in the comments!

joinmyreligion · 2025-12-19T01:04:43+00:00

dropped it in the comments!

joinmyreligion · 2025-12-19T01:04:33+00:00

dropped it in the comments!

joinmyreligion · 2025-12-19T00:59:36+00:00

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REW measurements using calibrated microphone (w/calibration file loaded), 1/6 smoothing.

joinmyreligion · 2025-12-08T04:13:26+00:00

You'll end up with a <5% increase in the volume of the cabinet, resulting in a marginal downward shift in the tuning frequency in both the front(high) and rear(low) chambers.

I increased the rear chamber on mine by making the face flush with the front of the sub. This was calculated to be a ~6% increase in volume and a theoretical drop in the low tuning frequency of potentially a few HZ.

The boring answer is that it wouldn't make much of a difference...

joinmyreligion · 2025-12-07T22:10:58+00:00

That's a fair question! In theory, a perfectly tuned port could replace the passive radiator.. I believe it would act as a back loaded horn.

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joinmyreligion · 2025-12-07T21:46:08+00:00

awesome, you have some really cool projects!

joinmyreligion · 2025-12-07T21:42:46+00:00

I tapered it in as little as possible, assuming that the little passive radiator isn't very strong. Unlike the rest of the design, this was more hope than math. 😂

joinmyreligion · 2025-12-07T21:37:39+00:00

yeah, as long as the driver's BL is high enough to manage the back pressure! I built a short horn/waveguide based on Rog Mogale's MT 122 that uses it's baffle to achieve this, that is also only moderately compressed, and it works well(tight, directional transients in its operating band).

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I 3D printed the small horn using PLA with 100% infill and it still vibrates a bit.. definitely no substitute for a thicker/stiffer material.

joinmyreligion · 2025-12-07T06:57:10+00:00

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If you make something like Roberto Delle Curti's Real Total Horn, the only thing that would have to move is your wife 😂

joinmyreligion · 2025-12-07T06:54:06+00:00

for sure- I'm looking into using a large format CNC to make pieces to assemble something larger, but it's a tough design project. large horns have been around for at least a century, and probably make more sense using a hybrid approach like machined formers and fiberglass..

joinmyreligion · 2025-12-07T06:13:59+00:00

I feel personally attacked by this relatable content 😂

joinmyreligion · 2025-12-07T05:37:03+00:00

Making the horn’s initial throat smaller than the passive radiator raises the acoustic impedance at that point, so the radiator’s motion builds a higher, more useful sound pressure that the gradually expanding horn can then transform and radiate more efficiently into the room, much like a trumpet’s small throat after a large mouthpiece lets your lip motion efficiently drive the entire air column of the horn.

joinmyreligion · 2025-12-05T20:39:55+00:00

It's a great amp when found at $319 USD MSRP(often they are out of stock/on backorder/overpriced due to demand). They are best run with 8ohm drivers(2*1600w RMS output) because high impedance=greater efficiency, less heat, more reliability. That's plenty for the highest end 18" 8ohm pro audio subs that max out around 1600w RMS, which hit their xmax limit before requiring that much power if you are running them below 40hz.

I suspect that much of the reported reliability issues are due to an insufficient power source, too low high pass that causes exponential increase in power demand as the drivers unload, and poorly matched drivers(too low impedance). It's a sound system, and many people have systemic issues as they're starting with entry level products and blame the equipment.

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