Help with under 300Hz for Monsoon MM-700 Planars

Do you mean a single driver for each speaker (one for left and one for right) or literally one driver to cover both left and right up to 300 Hz?

How large are you willing to go on the enclosure?

How low do you want it to go?

Do you have a preference for how amplification is done? Do you want a single amp to drive everything (2.1 channel amp) or do you want flexibility so you can use different amps?

Similarly, active crossover or passive?
 
frugal-phile™
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Quite surprising how high you can go with a single woofer handling the mixed-bass and still have good sound. Kind of a myth that you need basic geometry to hear music. As far as I'm concerned, "stereo" means sound filling the room and maybe some directionality.

With your new speakers flanking your monitor, no problem having the sound below 300 Hz arrive from a single speaker on the floor out of sight.

B.
 
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Do you mean a single driver for each speaker (one for left and one for right) or literally one driver to cover both left and right up to 300 Hz?

How large are you willing to go on the enclosure?

How low do you want it to go?

Do you have a preference for how amplification is done? Do you want a single amp to drive everything (2.1 channel amp) or do you want flexibility so you can use different amps?

Similarly, active crossover or passive?
 
Do you mean a single driver for each speaker (one for left and one for right) or literally one driver to cover both left and right up to 300 Hz?

How large are you willing to go on the enclosure?

How low do you want it to go?

Do you have a preference for how amplification is done? Do you want a single amp to drive everything (2.1 channel amp) or do you want flexibility so you can use different amps?

Similarly, active crossover or passive?
Those are all the right questions. I am using a Loxjie A30, USB DAC amp, 40w x2 @8ohms, with a single subwoofer out. The single sub out has no crossover setting, is mono, and may even be full range. Now that I have thought about it, I am concerned I might be missing out on localization/directionality of the 100-300Hz region.

So, I think a stereo 2-way configuration with a yet to be determined crossover point is my goal, all powered by the Loxjie. I do want a smaller footprint, internal box dimensions around 0.125cuft (6” x 6” x 6”)
 
Quite surprising how high you can go with a single woofer handling the mixed-bass and still have good sound. Kind of a myth that you need basic geometry to hear music. As far as I'm concerned, "stereo" means sound filling the room and maybe some directionality.

With your new speakers flanking your monitor, no problem having the sound below 300 Hz arrive from a single speaker on the floor out of sight.

B.
Probably true, but I am not taking that chance. People said the Monsoon sub was an issue.
 
Are you OK with a ported box? It's tough to get very low in a small box without some help of some kind (EQ, port, etc.), especially if you want to stretch up into the midrange.

Could you give a price range you're hoping for on each woofer?
Ported or with a passive radiator, but the footprint must be small, .125 cuft
Price? Like to stay at $100 incl. crossover, $80 tops for drivers.
Thx!
 
Yeah, I saw those. In fact, I think the Passive Aggressive Mini Speaker Kit at Parts Express has a design I will go with. It is the ND91-4 paired with two ND90-PR passive radiators, recommended enclosure volume of 0.045 cuft. It goes over my cost limit (like that ever holds true), but it is a small footprint. I'll just delete the tweeter.

I will measure the Monsoon MM-700D when I get home tomorrow. Then will need help with crossover design that might need an attenuation circuit.
 
Ok, they are 2.9 Ohm static, so must be 4ohm drivers, same as my planned bass modules. I have no idea what would be the best crossover point or type of crossover. I read somewhere that electrostatics like steep crossover points. And, which driver will need to be attenuated, the bass module or the Monsoons? I will build the crossover pair as a separate box, so it would be accessible.
Ok, any input folks? Thx!
 
Probably true, but I am not taking that chance. People said the Monsoon sub was an issue.
Not sure just what "chance" you aren't taking (in my post #6)?

Very easy to mock-up a test. Here's what anybody would expect to be a totally awful arrangement:

Take any spare speaker (in an enclosure or just raw) and feed it L or R and stick it under your desk with the L and R upper frequency speakers in their location on top of your desk.

Does the music sound totally awful? Or is it a sound stage you could live with, given how simple it would be to set up with a proper mixed bass (not just L or R full-range under the desk)?

B.
 
Not sure just what "chance" you aren't taking (in my post #6)?

Very easy to mock-up a test. Here's what anybody would expect to be a totally awful arrangement:

Take any spare speaker (in an enclosure or just raw) and feed it L or R and stick it under your desk with the L and R upper frequency speakers in their location on top of your desk.

Does the music sound totally awful? Or is it a sound stage you could live with, given how simple it would be to set up with a proper mixed bass (not just L or R full-range under the desk)?
No plans to put anything under my desk. Since I am going to go with the small form factor bass modules (.045cuft), I will just place them next to the Monsoons on my desktop (I have a big desk). A true 2-way setup. Also, this lets me just use the Loxjie A30 for power and does not necessitate an extra amp for a larger single sub.
 
I have no idea what would be the best crossover point or type of crossover. I read somewhere that electrostatics like steep crossover points. And, which driver will need to be attenuated, the bass module or the Monsoons?
What is likely to be attenuated is going to be influenced by what frequency range you want to go to the planar. The lower it plays, the more response shaping you'll need on it (to make up for the dipole cancellation mentioned earlier), which is going to cost sensitivity. In that scenario you may need to attenuate the woofer.

If you cross higher, you may get a better sensitivity match between the woofer and planar. Or you might even need to attenuate the planar, assuming the frequency response plots here are at 2.83 V and 1 meter.

https://www.diyaudio.com/community/threads/monsoon-speaker-parts.391848/#post-7182604

The Monsoons are planar magnetics, which often have more excursion and output per unit area than an electrostatic panel. Like most mid/high frequency speakers, if you cross them higher you can normally get away with a more shallow crossover.
 
What is likely to be attenuated is going to be influenced by what frequency range you want to go to the planar. The lower it plays, the more response shaping you'll need on it (to make up for the dipole cancellation mentioned earlier), which is going to cost sensitivity. In that scenario you may need to attenuate the woofer.

If you cross higher, you may get a better sensitivity match between the woofer and planar. Or you might even need to attenuate the planar, assuming the frequency response plots here are at 2.83 V and 1 meter.

https://www.diyaudio.com/community/threads/monsoon-speaker-parts.391848/#post-7182604

The Monsoons are planar magnetics, which often have more excursion and output per unit area than an electrostatic panel. Like most mid/high frequency speakers, if you cross them higher you can normally get away with a more shallow crossover.
That thread helped, and I see that Adason (wish I knew how to tag him on this forum) thought they should crossover at 500Hz, but he was building a 4-way. I found some specs for the MM-700 and it turns out they were given 11 watts each with an active 3rd order crossover at 250Hz.