Shallow speakers for home theater

babinsky · 2023-11-09 6:18 pm

A signal generator could help narrow down the frequency band even without a mic. If your system is/can easily be hooked up to a computer (or at the minimum a smartphone if you can find some decent apps), one idea could be to use Audacity to generate chirps. (A music keyboard would also work).

Home in on the most audible bumps and warbles that shouldn't be there, and find out what the frequencies are. Then convert those to wavelengths and half-wavelengths and take the detective work from there. My 2c

Thanks. I did something like that using a Youtube video but I am not sure what I can take away from that... :/ :

the amp was definitely messing things up. I will go the the documentation to see if there is a mode where DSP/Room correction is disabled.
I can't gate my ears, so it is hard to know what comes from the speaker and what part is the room. In particular, I don't know what to take away for freqs below ~200-300Hz, where room modes might dominate. For example I could definitely hear my room modes (big sound at 32 and 65 Hz 🙂 ). I guess this can be mitigated by doing it outside but it is raining like crazy these days.

I'm not assuming anything, the backwave IS creating time based delay.....whether or not you can hear it or if it matters is up to you. The critical analysis has been done countless times over decades and the resources are available to you for confirmation. Sounds like what your asking for is subjective confirmation?

Quite the opposite, I am asking for a way to observe/measure the issue. So that if I try a fix, I can confirm that it indeed fixes the issue.

Not sure how we wound up hyper focused on this when your predominant issue is the terrible 10khz breakup that makes you want to turn it down that you mentioned earlier. I would suggest a measurement mic and freeware so you can quantify it with your eye and then notch it with a passive component filter.

The plan is to do it actively. I already turned the highs some by ear for now, at least for it to not be subjectively harsh (using a youtube test tone and playing with the EQ of the amplifier, ). I will do it more accurately with a mic when I get one.

Please excuse me if i'm coming off as snarky but i'd rather not waste my time trying to assist you if in the end, subjective group think drives your efforts

No offense taken 🙂 . I am very much a data-driven person (you will see that I was looking for driver measurements to make a selection beforehand). Now that I have a prototype, my approach is as follow.

first listen to it, and observe if something sounds off
measure it and correlate the measurements to what I heard. I want to listen first to not be biased by measurements and focus on fixing actual issues that bother my listening experience vs just engineering challenge.
then ask this forum for help to fix the issues

This is why I was asking how the backwave issue would show up in listening sessions (part 1) and measurements (part 2).

freddi · 2023-11-10 4:39 am

I have "K3.5" speakers with 3fe35 Faital and with a $40 Kinter 2.1 amplifier, plays pretty loud with the "sub" amp driving an Eminence Kappa 12A in my "Karlson Kube" (drumkit and pipe organ do well despite having nothing much below 60Hz.) - Kinter says the point one rolls off above 180 Hz (dunno if there is any highpass oz the stereo part -?) anyhow small drivers might be doable if you go to 150--180 Hz crossover.

mattstat · 2023-11-12 7:12 pm

mayhem13 said:
Mattstat attacked the premise

Mattstat didn't attack a premise. He didn't make blanket statements or state opinions unequivocally. He relayed his experiences, defended a thread someone dismissed as "a mess" and an "example of why forums often are more harmful than helpful." He also tried to point out some obvious geometry issues in nearly every speaker, admitted that he previously had similar concerns about shallow enclosures, and suggested that building things is sometimes necessary to separate speculation from experience.

I admit to being guilty of suggesting that someone listen to their speakers and decide if they like them on numerous occasions. I've also suggested several times that some people aren't trying to build perfect speakers, but those that suit their needs. When is the next struggle session?

These back-and-forths bore me, but here are some other people that apparently don't know what they're doing:

Steinway Lyngdorf
https://www.soundandvision.com/content/steinway-lyngdorf-s-15-speaker-system
"it’s 10 inches tall, 8 inches wide, and only 3 inches thick"