To Sub Or Not To Sub, That Is The Question

[Musical Bass]

Yes look for the graph for passive MS-6P. The above graph is with high pass at 25 Hz and crossover at 200Hz.

Would like to get a review here with a music system! Our favorite customers are panel owners!

It says right there on the graph that it's 1/6th. Or are you referring to a different graph?

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[Musical Bass]

Would like to get a review here with a music system! Our favorite customers are panel owners!

Would like to get a review here with a music system! Our favorite customers are panel owners!

Would like to get a review here with a music system! Our favorite customers are panel owners!

This graph is without eq with crossover set at 75Hz -12db slope. There is a small peak at 80Hz that I would temper with DSP. The sub is located at the junction of wall and floor actually under a table. It’s using 8 watts to produce this graph with mic on opposite side of room. The satellites that act as mains are crossed over at 100Hz -6db/Oct slope. We find that a shallow slope starting high sounds best! They are not connected for this graph.

 

[DonH50]

Servo means creating more pressure! You must remember the actions of compressed air molecules is to fight back! When you compress them they help the driver in the reverse direction! Compressing then expanding while the signal inputs what is correct! Common sense but ignored because no solution! Those technologies that you mentioned have not solved the issues as they still exist! Power (force) does not overcome these issues! The MS-6P is operating with a maximum of 100w and typical power required at 30 Hz@ 95db+ in moderate size room with low distortion is about 20W. If you can modulate the pressure you reduce distortion and increase the efficiency!

There is a language barrier or you do not have the same concepts of (or express the same way) acoustics, electronics, and physics that I learned in graduate school and through my career.

Servo control can be applied to sealed, ported, open-baffle, passive radiator-loaded, or dual-driver (opposed or symmetrically driven) speaker systems. Sound is a pressure wave comprising compression and rarefaction. By your definition the air is always "fighting back" when we listen.

Any speaker having sensitivity of about 90 dB/W/m will produce ~95 dB at a listening position of about 3 meters with 20 W input (independent of frequency, although speaker sensitivities at not usually specified at 30 Hz).

My common sense tells me there is no value to my continued participation. Have a good evening!

 

[Musical Bass]

Yes look for the graph for passive MS-6P. The above graph is with high pass at 25 Hz and crossover at 200Hz.

Why does the cabinet vibrate if there is not pressure that the drivers diaphragm surely feels! That pressure wants to escape. The diaphragm is the path of least resistance.

 

[sigbergaudio]

Yes look for the graph for passive MS-6P. The above graph is with high pass at 25 Hz and crossover at 200Hz.

I am unable to find it. Can you post a link to the webpage where it is presented?

 

[Holmz]

Room modes are dictated by room dimensions, does not matter the speaker (or subwoofer). The idea of equating room and speaker resonances to the Tacoma Narrows bridge failure, a result of underdamped resonance excited by wind, is not particularly relevant. Speakers are driven by amplifiers that control their motion, speakers (drivers) have suspensions (spider and surround) that reduce resonances, and room modes ("resonances") are independent of the speaker.

It could be stretched to work for a high order bandpass.
Which is like a kid on a swing, and takes a lot of pumping to get going.

But yeah, you’re right.
A seal box has no resonance by comparison.

"Speed" just means enough bandwidth to reproduce the frequency range of interest, which is pretty low for a subwoofer. System damping via driver, box, and amplifier designs help control transient response, another interpretation of "speed", but again for a subwoofer not a lot of bandwidth is needed for that. Any driver has mass, and high or low it is up to the amplifier driving it control the mass and "resonance". I think there must be a bit of a language barrier here, or a technical disconnect.

^All correct^… and probably a technical disconnect.

“Speed” is often used as a subjective term for group delay, or transcient response.
More so transcient response…

 

[Holmz]

…
My common sense tells me there is no value to my continued participation. Have a good evening!

But many of us like to read your words.

 

[sigbergaudio]

This graph is without eq with crossover set at 75Hz -12db slope. There is a small peak at 80Hz that I would temper with DSP. The sub is located at the junction of wall and floor actually under a table. It’s using 8 watts to produce this graph with mic on opposite side of room. The satellites that act as mains are crossed over at 100Hz -6db/Oct slope. We find that a shallow slope starting high sounds best! They are not connected for this graph.

Well this is even more smoothed, this is 1/3rd octave smoothing. You can not judge whether the response is even with this.