I have a chance to hear two versions of my speakers: real wood vs. MDF enclosures. I could detect the emphasis on male’s voice on the real wood cabinet version—there’s Umm sound along with male’s voice. So, I suspect the emphasized men’s vocal I heard was the cabinet talks.
How to find the cabinet talk frequencies?
In fact, to find it, I know there’s using accelerometer method but is there any easier method?
Also, to fix it, I think of crossover design that help fix the issue. Can I break the theory by designing the crossover in custom way, i.e., underlapping crossover points, instead of employing some sophisticated specific circuits such as notch filters?
How to find the cabinet talk frequencies?
In fact, to find it, I know there’s using accelerometer method but is there any easier method?
Also, to fix it, I think of crossover design that help fix the issue. Can I break the theory by designing the crossover in custom way, i.e., underlapping crossover points, instead of employing some sophisticated specific circuits such as notch filters?
Hook the driver as microphone and knock the walls.
What I think is if the measurement shows the cabinet talk frequency occurs at, for example, 380-560Hz, I would use the underlap crossover in that frequency range. IOW, the low-pass of the woofers will not be higher than 380Hz and high-pass of the midrange will not be lower than 560Hz. Something like this.
Yes. In other words you will equalise it. It doesn't matter how you do it, that's how I see it being described.
However there's one catch. Equalising something that has had additional delay from the sound the driver makes.. a double sound.. doesn't equalise the same. You will get some benefit. The same could be said about sound coming from a different location, ie the panel. You can equalise it a little but not completely.
However there's one catch. Equalising something that has had additional delay from the sound the driver makes.. a double sound.. doesn't equalise the same. You will get some benefit. The same could be said about sound coming from a different location, ie the panel. You can equalise it a little but not completely.
Make a speaker wire with XLR connector on the other end so you can hook the driver into computer sound card mic input. So instead of connecting it to an amplifier you use it as microphone.
Now measure with the driver as microphone, knock the cabinet with your fist or with some mallet to various places on your box walls and see what the driver hears. Any wall resonancse should show up as peak(s). There are multiple peaks, driver resonance, sound of your knock, and any sound in the room as the driver is quite sensitive microphone but you likely identify these.
You might find a spot where knock makes particular loud sound (measured by driver), here you want to add bracing for example. If it's just broad band noise you measure then perhaps add damping material and try again.
Another cheap/easy is to use sine wave try and listen or measure what frequency seems to make the box sing, perhaps you can now feel the panels with your fingertips and try to find which one resonates.
These are not particularly scientific methods, but rather easy ways try and improve on things. It's hard to measure how much sound the enclosure emits.
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A cheap mechanic's stethoscope is your best friend for finding resonances, 'hot spots'.
Guitar peizo pickups were actually designed to pick up vibes in wood, but frankening is more fun
Yes, I use them to evaluate cabinet performance on every project I build. I play pink noise through the speaker, then I use the stethoscope to listen to various areas of the cabinet. A well behaved cabinet should sound like pink noise, and most areas of the cabinet sound that way. If I hear a specific note, or tone, or character to the sound, it means I have a resonance. It is often possible to guess the approximate frequency of the tone.
