UMII8-22 Ultimax II 8"

Just made my first desktop speakers and somebody had to say "why not a sub?"

This will be a down firing up ported(for now) 22.5mm thick walls that i can thin for a bit more volume if needed.

I hope the math in the program is right with 35hz assuming i plugged in everything right(very new to this) but AI had a similar response so hoping we good.

Already did test prints with all the tight fits and we are already printing the top half.

Printing time for 5walls/30inf is 36HR per half and 3.5 ROLLS of filament each...

Hate it? think I should change it up? think it will blow up?

Fun project I worked on to challenge myself. Had to brush up on my 3d modeling and forced myself to learn hornresp. Still lots of finishing work and measuring/testing ahead but it’s got great output to ~30hz and already rattled some tools off my workshop wall

Hi, a small follow-up to my previous post.

My original experiment was simply to see whether an AI agent could use the Parts Express catalogue to suggest matching drivers and crossover components for a small, cheap speaker.

The new repository contains Python calculators, a reference knowledge base, and agent instructions:
https://github.com/meowelectronics/ai-speaker-design-database

This is still an knowledge database, not a substitute for proper speaker measurements. An agent can suggest something plausible and run calculations, but that doesn’t make its assumptions correct or the resulting crossover ready to build. Manufacturer curves are not measurements of your actual baffle, and the catalogue hasn’t been checked entry by entry. However, it can be added and it can calculate with it.

The idea is to make the calculations, sources, and missing inputs easier to inspect instead of just getting “use these drivers and these parts” from a chatbot.

What Is Included

• Driver T/S conversions, sealed/vented/passive-radiator/aperiodic small-signal models, complex impedance, excursion, port geometry, and estimated voltage ceilings.
• Measured FRD/ZMA import, phase and angle interpolation, microphone corrections, complex-impedance fitting, baffle diffraction, and ideal piston directivity.
• Passive multiway networks, two-way component search, active/DSP filters, acoustic summation, impedance phase, group delay, and coverage checks.
• A rebuildable JSON-to-SQLite knowledge base with equations, citations, assumptions, workflow stages, and documented limitations.
• Agent intake and specialist review workflows, a blank design brief, generated Markdown/LaTeX reports, optional PDF compilation, and input-hash manifests.
• A WinISD importer that preserves raw fields, source hashes, duplicate identities, SI parameters, and screening flags; no WinISD driver payloads are bundled.

You might find it useful. Use it as you want.

P.S. this text was formated and polished during github push by github copilot via VScode. I wrote it personally. I am not a native speaker and I am not an AI bot.

The next step : I am waiting for TS parameter measuring tool. Then I want to order speakers and actually make what the agent suggested.

Good afternoon, everyone. I need help connecting the correct wires for my Marantz Code 30/300 speakers. I’m not sure if the current setup is right; the tweeters are barely audible—the sound is almost imperceptible—while the mid-range is quite shrill and annoying. There are three wires coming from the capacitors: yellow, red, and black. Then you have the ones soldered together: there are yellow/black, orange and red and black wires. Thanks a lot. I have them connected to a Sony MHC-G88; I haven't hooked up the satellite speakers yet—could that be the cause for the way they sound? Woofer is not sounding great either...

So I needed a mid(bass) speaker + cabinet for a range 100+hz (115hz LR4 xo)) to about 1000hz to accompany my SKRAM subwoofers and 18sound ND3N CD+twinray printed horns (in this case taking over from 1000hz on an lr4 slope).

The aim was as small as possible and also ceiling mounted. Another negative factor. I built 2 32ltr plywood cabs but then ive seen guys reproduce reasonable bass cabinets, sub 50hz from a PLA printed cab, I had Claude made me a drawing for a 9ltr and started printing. It still is an experimental setup so bear with me, but yesterday I could put up the PLA printed cab and do some REW measurements vs the plywood cabinet at the other side of my room, also near the ceiling.

I have to say: the measurements are better than I expected. The PLA looks more flat and only sub 200 seems to fall off a bit more than the plywood. The ear doesnt hear it though. I decided to put up all the graphics tabs on here and let you decide for yourself. Do note: its still not a very loud test, and I also should do a same position A vs B test to see how much is room, room positioning etc. Of course the room itself also mixes in but sofar I am very positive and this is certainly not a failed experiment. The driver helps, an 18sound 10" 10NW750 the 16 ohm version.

The plywood cab measurements are noted as 'wood'' in rew, and the PLA cab as 'pla' or 'new''. The amplifier used is a Behringer inuke 6000 and the DSP used a minidsp flex eight. The pre amp is a quad 34. The microphone is a umik I. I made measurements on 3 positions but everything not SPL is form position 1. I did include an averaged from the 3 positions, and the single spl measurement form position 1.

Is it possible to add a LINE OUT to this ZKHT21 2.1 amplifier to connect another independent amplifier and headphones?

I have this ZKHT21 board, powered by a 36 V / 10 A power supply (2 × 160 W stereo + 220 W mono subwoofer).

• Is there a safe way to do this?
• Where exactly should I connect L / R / GND?
• Are any additional components required?

I have basic electronics and soldering skills. I have attached a picture of the board.

Thanks for your patience!

📌 Edit 1: WHY? Because I want the option, now or in the future, to connect another independent device and/or amplifier.

📌 Edit 2: I have already considered possible high-to-low converters, but I don't really trust them, since practically all of them are rated for NO MORE than 40–50 W per channel. (My amplifier is powered by 36 V / 10 A.)

Putting together some stands for my bookshelves for my lowboard (see photo).

My logic was hard bamboo which doesn't resonate glued to soft pine to absorb resonance that is happening, then spike feet, and those on furniture pads for good measure.

However what am not sure of: Is there a tangible reason to have the speaker on the hard bamboo and the soft pine connected to the feet or *vice versa*?

Or am I overthinking it/does it not matter?

(Picture of a 'dry' test fit bamboo on top. Still want to stain and seal the wood.)

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Hi guys, taking on my first ever build for speakers and going with the mechano23 however using MDF. My inspired cabinet look is the B&W 607 with the oak outer and white baffle.

Hence anyone recommend a good quality vinyl wrapping? I know I could veneer but I think vinyl would be easier....

Pic from chat however minus the front port for inspiration

My second and far more sane build. I had the tweeter overdamped at first, electrically. Then the box overdamped with denim. Chased those both back and now it's a great sounding speaker. Port is tuned in the 40's, the sub is strictly on LFE duty. Will re=consider the sub (and surrounding cabinet) long term if these stay up on the wall.

LR4 crossover around 2khz. Cabinet is very stiff (acacia and 3/4" birch ply) but still a little back-wall resonance that I need to insulate against a little better I think. Currently has some silicone foam pad but that's doing a great job of vibration damping it's not doing much to kill the sound wave bounce back. 2 walls have 1.5" denim (was five walls but it was killing the midrange spoken vocals).

Maybe 2x 12's in sealed boxes. Maybe a different cabinet to fix the r/tvtoohigh.