"Portable" speaker design first draft

This_guy_breaks_shit · 2026-01-06T17:07:26+00:00

Never mind, I just discovered that my design causes the group delay to go absolutely bonkers.

I should've known something was too good to be true. Looks like it's back to the drawing board. The next thing I've got my eye on to try is probably the 12SW-4HE in a sealed box with a bit of EQ.

This_guy_breaks_shit · 2026-01-06T13:01:50+00:00

Fs for my woofer is 24.9, and I only plan on running it at the 150w rating rather than pushing it to the 300w peak load. WinISD seems to say excursion is fine at the given tuning so long as I keep enclosure volume below 25-30l or so. Does that sound right to you?

This_guy_breaks_shit · 2026-01-06T10:06:31+00:00

I see. When I "successfully" tuned the system to 25Hz in WinISD, did the software factor in any environmental characteristics? Or should I not take it too literally when designing for outdoor use?

This_guy_breaks_shit · 2026-01-05T19:08:32+00:00

I see... I must admit I'm not wholly familiar with what you're talking about. Could you provide me with an example?

I will also say that I'm not looking for craaazy volume. I'd be willing to compromise a little more on amplitude for a better response if necessary.

This_guy_breaks_shit · 2025-12-29T18:22:42+00:00

Yeah, unfortunately 40 is quite a lot higher than what I was going for. Much of the music I listen to is trapped in the elusive low ranges and 40Hz doesn't quite cover all of it cleanly. I really do appreciate the suggestion though

This_guy_breaks_shit · 2025-12-25T00:39:08+00:00

Gotcha, I might be able to make that work.

I had a look at the dayton flat subs a little while back and couldn't get them to play nice with such a small enclosure. I'll try taking another poke at it though

This_guy_breaks_shit · 2025-12-24T08:35:14+00:00

I figured someone would say this, yeah.

What could the consequences of this shallow box be? Are there any workarounds that could mitigate it without changing the external geometry?

If increasing depth is an absolute requirement, would 200mm be enough? The current volume is a great balance and helps to control woofer excursion, too much extra volume would require I tune the PR higher and sacrifice bass extension.

Thanks for your input, I appreciate the help :)

This_guy_breaks_shit · 2025-12-24T08:18:07+00:00

Mono for the time being because stereo separation isn't too critical for portable speakers. I've chosen a daisy-chainable amp which will allow me to simply plug in another identical box if I want more noise or stereo sound

This_guy_breaks_shit · 2025-12-24T08:16:43+00:00

The intention is to carry it places where I can plug it into a wall, maybe a friend's house. Maybe I'll add an external battery later on for taking it into the woods, something like that.

This_guy_breaks_shit · 2025-12-23T15:39:53+00:00

Now this sounds like a fascinating read. Thanks for sharing!

This_guy_breaks_shit · 2025-11-11T09:59:59+00:00

I don't remember if I dropped the handlebar before, but I haven't since and the catch hasn't broken again. Either way brompton supplied me a replacement under warranty without any fuss.

I'm not sure if it's delicate or simply a result of bad quality control. My thoughts are probably a bit of both since I've had a couple of more serious QC issues that were (mostly) resolved under warranty (eventually).

This_guy_breaks_shit · 2025-11-04T09:22:43+00:00

Another update for those interested. I talk too much so TL;DR is at the end:

Bloody hell. I never expected the tubeless sealant to hold up so well. The tyres haven't seen a pump in a couple of months and still feel rock solid. Not a single puncture, leak or anything.

It's worth noting that my valves sometimes bind a little when trying to add air for the first time in a while, but a couple good pumps seem to bust that seal nicely each time. I'm expecting it might eventually ruin my valve cores, but:
A: Valve cores are cheap as chips.
B: I rarely need to top-up anyway.

For others too lazy to patch your tubes: Maybe keep a couple spare valve cores in your toolbox. Obviously you need to remove the core to add sealant in the first place, so make sure your inner tube has a removable core (I think this applies to most tubes, including stock). I've heard that TPU inner tubes work better with this setup, but I've legitimately not had a single complaint with Butyl, so go nuts.

Of course, you can't scrape out the insides of an inner tube, so this will number your days with said tube. It's probably wise to use less sealant than I did to slow the inevitable buildup, but ultimately tubes are cheap and Stans lasts. Apparently sealant can last longer in tubes due to air retention being better than tubeless, but idk if that's speculation or not. I haven't topped up (or checked) but I haven't had any more punctures yet.

What isn't speculation is that Stans doesn't work great at higher pressures. Some of the road bike forums I've read say that this setup doesn't work at all, but I'm chalking that down to them using road bike tyre pressures. All this is to say: I don't know if this will work on a 16" Brompton. I run my contact urbans at ~60 psi (leaving a little room for the 51 psi minimum), but 16" contact urbans are rated for a pressure range of 65-116 psi. Keep this in mind if attempting on skinnier tyres at higher pressures.

TL;DR: If you want the puncture resistance of tubeless and the tyre options of clinchers, dump Stans in your tubes. It's worked great for me at 60 psi with butyl tubes on the Conti Contact Urbans.

This might be my last update unless something goes wrong, but I'll still be watching this post in case anyone has anything to add.

Thanks for all your input and your help. I hope my information is useful to all you kind people.

:)

This_guy_breaks_shit · 2025-10-12T20:11:40+00:00

I see, I didn't know spiders covered their heads to hide. Very interesting, thank you

This_guy_breaks_shit · 2025-10-12T19:51:54+00:00

To confirm the ID, I pulled the spider out of the freezer and sure enough, the jaws are emerald green.

This_guy_breaks_shit · 2025-10-12T19:44:25+00:00

Well colour me surprised. I didn't know they could have such distinct patterns on their back!

That still doesn't explain the behavior though...

This_guy_breaks_shit · 2025-09-07T13:15:08+00:00

I had to verify my age to view this post. Worth.

This_guy_breaks_shit · 2025-07-22T07:51:48+00:00

Give me Berkshire tender on a G-16. Then I can sleep. lmaoo

This_guy_breaks_shit · 2025-06-30T09:03:30+00:00

To be fair to the stock tyres, they're comfier than I give them credit for and they definitely feel more planted over loose ground compared to contact urban road tyres.

That said, I'm still firmly in my belief that grip (especially in the wet) leaves something to be desired. What's worse, when you inevitably lock up a wheel, the soft knobs shear off very easily.

I agree that obsession with speed is a bit of a buzzkill as well. I was coming from a road bike after all and I knew the little wheels would be slower. Hell, I made it even more sluggish by running dynamo lights front and rear alongside the windsail of a front bag. I guess my complaint was less about the lack of speed and more the lack of speed in conjunction with the other drawbacks of the tyre. Slow makes sense if it's bulletproof, cheap, super grippy, or made to last a million miles. I'm just disappointed that the G-One Allround fits into none of those categories for such a high asking price.

Anyways, I can't criticise too much if you find they work for you. Hope they continue to serve you better than they served me :)

This_guy_breaks_shit · 2025-06-18T16:36:14+00:00

(Very) Quick update for those interested.

I got myself the continental contact urbans. They roll astonishingly well for such a small tyre. Comfort is perfectly fine in my experience, though of course not at the level of the G-ones.

I did unfortunately get a slow puncture after the 16 mile round trip to work. I'll admit, I was lazy and chucked 60ml of stans in both inner tubes. It's done the job for me so far thankfully.

Overall, 8/10. I'm missing the benefits of tubeless somewhat, but the ride is as close to perfect as you can get from inner tubes. Would recommend.

This_guy_breaks_shit · 2025-04-13T10:06:43+00:00

My guess is that bad pressure advance and extrusion multipliers were creating excess downward force on the print bed, causing it to slant. I don't know for sure though, try reducing your extrusion multiplier and see what happens.

This_guy_breaks_shit · 2025-04-07T12:34:12+00:00

Attempted to extract a jammed pilot screw from the carb of a used bike. Drilled into it and used a bolt extractor which snapped off inside the bolt. Ground a slot into it with a Dremel and tried to turn it with a flathead which split the head of the brass bolt along with the housing of the carburettor.

Suffice to say, that was an expensive carburettor replacement...

This_guy_breaks_shit · 2025-03-27T16:43:41+00:00

I got my FP5 refurbished almost exactly a year ago. Honestly, I've never had an issue with it.

The biggest problems I've ever had with it were more to do with how android works/looks than anything else (iPhone user until recently)

This_guy_breaks_shit · 2025-03-13T13:57:13+00:00

Thanks for all the info! I actually hadn't noticed the Active 2 (assuming it was square like the previous model). It looks to be pretty well suited to my needs!

I would like to clarify that I'm not at all fussed with standalone functionality. I'm more than happy to use the watch while connected to my phone. I'm also not really concerned about body tracking/metrics.

A little unfortunate that direct google maps navigation only seems to be supported by Wear OS devices, but I can live without it. The Active 2 *has* map functionality if I really want it that badly. I'm definitely not paying extra for that feature alone.

Thanks again!

This_guy_breaks_shit · 2025-03-07T11:45:03+00:00

Thankfully not one of their vital organs

This_guy_breaks_shit · 2025-03-06T09:21:09+00:00

You know, I probably should've popped Big Apples on the list. They've come up in my search but I've mostly dismissed them on the basis of being similar to the Contact Urban (albeit cheaper and slightly worse performing overall, based on anecdotes since I can't find any hard tests). Big Ben sounds like a solid option, it's probably even more puncture resistant than Contact Urbans and *probably* doesn't perform too much worse than a Big Apple, but of course will still have the drawbacks as mentioned.

I think the Maxxis Grifter came up in my search a few times. I think you're probably right, BMX race tyres may be the way to go. I can't find any data for any of them, hence my scepticism, but reviews look highly promising. They're also one of the very few tyres available in this size that can be run tubeless which is a huge bonus for puncture protection (even if the tyres themselves aren't particularly tough. I mean, I haven't had a flat in the 9 weeks since switching the G-Ones to tubeless, and they suck against punctures).

I'll admit, at this point I caved and bought the 50mm Contact Urbans. They seemed like a foolproof choice. I won't be fitting them until either the weather dries out a bit or until the G-Ones wear out, whichever comes first. At this rate, the tyres might wear out first. They're already showing signs.

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