Monolith by Monoprice M12-S 12in THX Certified Sealed 500-Watt Powered Subwoofer
Product # 35142
$799.99
This item has been discontinued
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Why would you pick a sealed subwoofer over a ported subwoofer?
NOBORU H
on Jun 2, 2020
BEST ANSWER: I personally chose two sealed subs. Sealed subs are usually much smaller in floor space size than a ported sub in the same driver size. Sealed subs generally sound more accurate but do not play as loudly as a ported sub. This has a lot to do with the larger cabinet size of a ported sub and the free'er movement of the cone in the ported design. Overall, I preferred the accuracy of the sealed version but I am not opposed to buying ported subwoofers.
For best results get multiple subs to lower the effort needed to reach the desired decibel levels and naturally accuracy stops being a problem if each sub hardly has to work to reach the desired volumes. Basically, if the drivers barley need to move then they don't have a chance to distort.
For best results get multiple subs to lower the effort needed to reach the desired decibel levels and naturally accuracy stops being a problem if each sub hardly has to work to reach the desired volumes. Basically, if the drivers barley need to move then they don't have a chance to distort.
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- Kevin K on Jun 7, 2020
- Purchased on Feb 16, 2020
BEST ANSWER: I personally chose two sealed subs. Sealed subs are usually much smaller in floor space size than a ported sub in the same driver size. Sealed subs generally sound more accurate but do not play as loudly as a ported sub. This has a lot to do with the larger cabinet size of a ported sub and the free'er movement of the cone in the ported design. Overall, I preferred the accuracy of the sealed version but I am not opposed to buying ported subwoofers.
For best results get multiple subs to lower the effort needed to reach the desired decibel levels and naturally accuracy stops being a problem if each sub hardly has to work to reach the desired volumes. Basically, if the drivers barley need to move then they don't have a chance to distort.
For best results get multiple subs to lower the effort needed to reach the desired decibel levels and naturally accuracy stops being a problem if each sub hardly has to work to reach the desired volumes. Basically, if the drivers barley need to move then they don't have a chance to distort.
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- Inaccurate
- Kevin K on Jun 7, 2020
- Purchased on Feb 16, 2020
For a little tighter bass,less booming, better for music also. Really like the results, sounds fantastic.
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- Geoffrey F on Jun 2, 2020
- Purchased on Mar 8, 2020
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When will you have the final distortion measurements?
anon a
on Mar 11, 2019
BEST ANSWER: When the weather warms up in the midwest! The engineer lives in Wisconsin and the weather has been poor.
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- New User U Staff on Mar 12, 2019
BEST ANSWER: When the weather warms up in the midwest! The engineer lives in Wisconsin and the weather has been poor.
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- New User U Staff on Mar 12, 2019
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What's the output difference between the sealed 12" sub and the ported 12" sub in dB? Are we talking 3dB (double)?
A shopper
on Mar 25, 2019
BEST ANSWER: CEA outputs for both subwoofers are posted on the product page.
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- Inaccurate
- New User U Staff on Mar 25, 2019
BEST ANSWER: CEA outputs for both subwoofers are posted on the product page.
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- New User U Staff on Mar 25, 2019
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Is the grill fabric only or is there protection (plastic or metal) in the grille to prevent accidentally damaging the woofer?
A shopper
on Apr 1, 2019
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What is the typical level setting for the M12-S? Calibrated, my avr is at -2db and I have the level setting at about 3 o’clock, just past +6 dB. Seems high when compared to my settings on PSA and SVS subs. I will say it sounds good and no signs of distortion, just seems high. Hope the amp is okay. Is this normal for these amps / subs?
Michael L
on Apr 25, 2019
BEST ANSWER: This is completely normal for our subwoofers. The difference in gain is due to our subs needing to adhere to a THX spec that accommodates subwoofer output signal voltage levels on older THX certified processors and receivers. Therefore, you may find on ours you will need the knob at 2 or three o'clock versus another brands 11 o'clock.
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- New User U Staff on Apr 26, 2019
BEST ANSWER: This is completely normal for our subwoofers. The difference in gain is due to our subs needing to adhere to a THX spec that accommodates subwoofer output signal voltage levels on older THX certified processors and receivers. Therefore, you may find on ours you will need the knob at 2 or three o'clock versus another brands 11 o'clock.
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- New User U Staff on Apr 26, 2019
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With both ports plugged, would this 12" THX Ultra sub sound similar to the M12-S?
A shopper
on Jul 8, 2019

Monolith by Monoprice M12-S 12" THX Certified Sealed 500-Watt Powered Subwoofer

Monolith by Monoprice 12in THX Ultra Certified 500-Watt Subwoofer Amplifier
Vote for the best answer above!
Can the onboard low-pass filter be bypassed? If so, when bypassed, how does the frequency response differ above 200Hz?
Rick J
on Jan 4, 2021

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Reviews
4.9 / 5.0
11 Reviews
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Rated 4 out of 5
Great tight base
This def doesn’t boom like my previous JBL Sub-150 ported 10” box at lower volumes, I end up needing to adjust the gain boost on this at low volumes to get the same base... but that said, this unit has better sound quality control and much more kick at higher volumes. Guess that’s the difference going with a sealed box vs ported. All said, I still prefer this units sound quality over my JBL’s loose base quality.


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Rated 5 out of 5
Big is Better
It took me a while to get her tuned in, but it was well worth the process !
Great deep, vibrant base that is defined in sound and crystal clear
Great deep, vibrant base that is defined in sound and crystal clear
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Rated 5 out of 5
Monolith 12 S subwoofer
Punchy bass, class D power so there is virtually no heat to dissipate.
Standby mode on low power consumption also so you do not need to turn off. Great looking cabinet, stash it in the corner and forget it.
Great buy and price.
Standby mode on low power consumption also so you do not need to turn off. Great looking cabinet, stash it in the corner and forget it.
Great buy and price.
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Rated 5 out of 5
Great sound and bass. Very impressive.
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Rated 5 out of 5
Sonically, these subs are incredible. When you consider the price they’re even more incredible. They have extremely loud, clean output all the way down to 20 Hz with no audible distortion or coloration — I have never heard them strain at all.
I was considering getting a single 15” sub but opted for 2x 12” instead, and I’m very glad I did. They fit better in the room and I can run them in stereo when needed. Highly recommend.
I was considering getting a single 15” sub but opted for 2x 12” instead, and I’m very glad I did. They fit better in the room and I can run them in stereo when needed. Highly recommend.
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Rated 5 out of 5
Excellent, Powerful Subwoofer
Sub is extremely powerful and hits really low and clean. The THX volume setting on the sub is perfect in my experience so far. I even have the signal from my Denon at about -4 dB. It looks really great to boot and I’m looking forward to enjoying more movies with it. Monoprice has been an excellent partner during my “quarantine home theater upgrade” and I will be recommending them to friends and using them in the future as well. Thank you!
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Rated 5 out of 5
Had a pair for 3 months, love them.
I love these so much I wish I went with their flagship model because I want more of this quality sound. I definitely recommend.
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Rated 5 out of 5
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Rated 5 out of 5
What a beast
I bought this for my home theater room, it’s about 1200 square feet. This thing is overkill in a good way. Very powerful clear clean sound. I have it hooked up to my Sony 1100ES. It sounds great for music being sealed but shakes the room for movies. It does not get as low as my Rhytmik FV15HP, but it is very impressive for the price.
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Rated 5 out of 5
Sounds Awesome!
Part of a primarily Monolith System: Amazon Ultra HD music streaming from a Chromecast Audio via Monolith S/PDIF Toslink to a Monolith by Monoprice Desktop Balanced Headphone Amplifier used as a DAC and pre-amp/EQ, to the 2x200w Monolith amp, which feeds Klipsch Chorus speakers and a Monolith M12-S subwoofer via Monolith RCA cables.

Added Jan 19, 2020
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