This is stating to get interesting! Back nearly 20 years ago I used a book on speaker enclosure building to calculate the volume of a box and its ports to make a big woofer. They were only cheap 300w subs, but with the right box they really kicked! Looking forward to seeing the final results.
Once you get this finished I would like to see how it would do on your other channel. Finished in a nice cabinet or open baffle I think that it would do quite well. Hopefully it would encourage a wider audience to push outside of their comfort zone as well as to exercise some problem solving. We need more of both.
I have rigorously tested at least three different models of the Dayton Audio DATS, including the latest, Version 3, which features a black box. Unfortunately, none have provided reliable results. When comparing the data obtained from these devices to manual test outcomes for Voice Coil resistance, BL, Cms, and resonance, there is a significant discrepancy. My approach to testing has been meticulous: I constructed a specialized test bench designed to securely hold the woofers without any vibration. This bench is considerably heavy to prevent any overlap between woofer and bench resonances. Despite these efforts, the system's accuracy leaves much to be desired, falling far short of being either accurate or approximate.
You'd be hearing what a compressed recording af his speakers would sound like when played through your own, most likely inferior speakers. Not very informative.
If you have 2 identical speakers, one is rated at 4ohms/50watts and the other is 8ohms, is it safe to say the 8ohm speaker will require about 100watts to match the loudness? Also, if you have an amp rated at 8ohms/100watts per channel can it run a 4ohm/50watt speaker safely?
Interesting video John. I really like the test-dongle you have...didn't know such a thing existed. I also agree with you - the DC resistance of a speaker is only the starting point...I think the confusion for many people occurs because this term is frequently call speaker impedance. Though somewhat true, it is only valid at 0Hz. The actual impedance of the speaker is very complex (as you show), this is due to many factors: inductance of voice coil, frequency, parasitic capacitance, and mechanical characteristic which also has an effect on the counter-EMF generated as the coil moves through the magnetic field. Question: have you considered using dry sand instead of the metal weights? It _may_ produce more accurate results since I suspect the sand would be less likely to resonate. Messier though...
Guys get hung up on using steel and magnets for the added mass, saying something non-magnetic should be used. But I've tested that (before) and saw no difference. These weights and small magnets are just really convenient.
@@IBuildItScrapBin I agree the steel should have near-zero effect w.r.t. the magnetic field. I just thought the sand would be a better non-resonating mass that could be uniformly distributed. Perhaps I'm over-thinking this... Please continue with this series - speaker design has always fascinated me and brings together two passions: woodworking and quality music.
Where's a great place to visit in Canada🇨🇦? Other than speaker world since I heard it's closed for Covid.... I went to Niagara Falls and Toronto last year... Both were cool but Toronto was a bit busy for me... would love to see some nature and big city or nice city anyways... Wouldn't mind moving to the great north. I'm sure the grass isn't always greener but wouldn't mind it.
i was watching one of your old videos are you still using your old wooden pc in your office and is the pc remaining cool also what is the over all size thank you. I would like to build one since it is hard to find a good case.
Might have to disagree with the thought that imperial makes more sense than metric. Fractions and I don't get along. Even being a born and raised red blooded 'murican, I have to say metric makes much more sense and is much easier to perform math on. Still, even if I can never be an audiophile, it's fun to watch somebody having fun building something they enjoy, and learning/relearning/teaching along the way.
