• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

DIYSG HTM-12v2 Review

changer

Active Member
Joined
Dec 4, 2020
Messages
151
Likes
86
Funny to see the woofer suspension resonance which was discussed before now shows up in a similar way in the JBL M2 measurements. The same goes for other large mid bass woofers (such as the Faital 12PR320), seems to be a common problem and because of EBR in this frequency region, manufacturers probably just decided they'd leave it as is. So when JBL decided not to EQ for the resonance in the M2's woofer, which they could have done easily, what do you think was their rationale?
 

Zvu

Addicted to Fun and Learning
Joined
May 1, 2020
Messages
576
Likes
902
Location
Serbia
My presumption is that it isn't easily detectable (maybe at all) in listening tests with music. Otherwise i see no reason why wouldn't they correct it.
 

changer

Active Member
Joined
Dec 4, 2020
Messages
151
Likes
86
Correct me if I am wrong, but weren't you able to measure with relatively simple tools and a distance of 3 meters of mic and transducer to the nearest boundary the suspenion resonance in the Faital woofer? Woofer was even a little closer to the ground, right?
This is the test rig shown in one of JBL's brochures. Could be that the bottom of the cabinet is only around 2 meters above the flour, hard to judge. Woofer and waveguide both are about 30 cm in diameter, cabinet could be 65 cm. But then, we do not know if this measuring rig is not further extandable, at least there is some rail left. So maybe they should have seen it too. With all their possibilities, why would they allow them a window of uncertainty between near field and far field bass response? I would not construct a measurement room and rig for a whole lot of money that is leaves a shadow of doubt.

Screenshot 2021-08-26 144839.jpg
 

Zvu

Addicted to Fun and Learning
Joined
May 1, 2020
Messages
576
Likes
902
Location
Serbia
Correct me if I am wrong, but weren't you able to measure with relatively simple tools and a distance of 3 meters of mic and transducer to the nearest boundary the suspenion resonance in the Faital woofer? Woofer was even a little closer to the ground, right?

I did measure it. I'm not saying that JBL doesn't know about the resonance, i'm sure they do. My guess is that trained listeners weren't able to discern suspension resonance as negative in one of harman's blind listening tests so they decided that it isn't important and isn't worth the hassle.
 
Last edited:

changer

Active Member
Joined
Dec 4, 2020
Messages
151
Likes
86
Sorry, I did not read your message properly and yes, we agree they left it as is because it is probably imperceivable with program material.
 
  • Like
Reactions: Zvu

ooheadsoo

Member
Joined
Aug 14, 2020
Messages
54
Likes
38
Yup, look at those graphs. The HTM-12 has it's faults for sure, but the directivity and dynamics are excellent, and eq will fix a lot. Like some of these other speakers, they are typically used in environments where EQ is standard practice. Amazing what this kit gets you. A wider directivity is the main way these speakers are not in the same mold as the others. If Matt releases a revised woofer for a V3, I'd probably be interested.

I need to build a pair of woofers to cross at 2-300hz. My wife is getting displeased with the wood sitting in the living room.
 
Top Bottom