Monolith by Monoprice 12in THX Certified Ultra 500-Watt Subwoofer Amplifier
Product # 24457
UPC # 889028055953
$899.99
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What color is it? It appears to be more gray than black.
David K
on Nov 15, 2018
BEST ANSWER: The color is black. It's not a reddish black, dark gray, or blueish black, it's black black.. The unit has a bit of wood grain (may be plastic, looks like wood) so in pictures that grain likely reflects some light. In person the actual wood grain isn't very obvious. For a good size black box it looks nice. The chamfered edges help with the appearance.
I purchased four of the units around the middle of October. They arrived very well packed, double boxed, in perfect condition, and have worked flawlessly. Four subs this size aren't really required, but I have the room so why not.
I purchased four of the units around the middle of October. They arrived very well packed, double boxed, in perfect condition, and have worked flawlessly. Four subs this size aren't really required, but I have the room so why not.
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- Kay S on Nov 15, 2018
- Purchased on Sep 25, 2018
BEST ANSWER: The color is black. It's not a reddish black, dark gray, or blueish black, it's black black.. The unit has a bit of wood grain (may be plastic, looks like wood) so in pictures that grain likely reflects some light. In person the actual wood grain isn't very obvious. For a good size black box it looks nice. The chamfered edges help with the appearance.
I purchased four of the units around the middle of October. They arrived very well packed, double boxed, in perfect condition, and have worked flawlessly. Four subs this size aren't really required, but I have the room so why not.
I purchased four of the units around the middle of October. They arrived very well packed, double boxed, in perfect condition, and have worked flawlessly. Four subs this size aren't really required, but I have the room so why not.
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- Kay S on Nov 15, 2018
- Purchased on Sep 25, 2018
Its black not grey at all. If they could offer a version with a rustic finish (Restoration Hardware look) that would be killer ... if anyone is listening there are high quality cheap "rustic look" laminates from Italy that some companies (Barker modern) use to make rustic kitchen cabinets - its just high quality synthetic but would be very "current" if a sub was offered in such a finish... higher wife acceptance factor.... but it sounds great and looks fine (big and black).
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- Robert D on Nov 15, 2018
- Purchased on Nov 5, 2018
Finish of the Monoprice 12" THX Ultra Certified 500 watt subwoofer is satin black with attractive wood grain texture. The speaker surface is non reflective and blends well with earth toned furniture and speaker finishes.
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- dexter m on Nov 15, 2018
- Purchased on Oct 17, 2018
It's black. Not quite matte, but not glossy in any way. It's meant to look like a black Ash color, and matches the speakers in have with actual black Ash veneers quite nicely.
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- Eric P on Nov 15, 2018
- Purchased on May 20, 2018
This is what I would term piano black. It is BLACK with the grain pattern showing through. It is not GLOSS black. Color rendering on video screens can vary widely.
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- Todd on Nov 15, 2018
- Purchased on Sep 20, 2018
It is black. There is a wood grain finish which you can see from only a close distance.
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- Martin P on Nov 16, 2018
- Purchased on May 21, 2018
The sub is black. The grain pattern in veneer makes appear grey in picture.
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- Jeremy D on Nov 16, 2018
- Purchased on Oct 25, 2018
It is definitely black. I was very pleased with the look of this sub.
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- Jared W on Nov 15, 2018
- Purchased on Nov 2, 2018
It’s black. It’s got a wood grain texture, but it’s pure black.
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- Loris M on Nov 15, 2018
- Purchased on Sep 19, 2018
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Is this too big for a bedroom? 15' long x 10' wide?
Gary N
on Feb 20, 2020
BEST ANSWER: As far as sound I’d say no. I think one will be great in that size space. I would suggest measuring and mocking up the physical space it’ll take up. These are large subs. I measured around my previous subs and thought they would be perfect. They seemed much larger when they arrived. I love them but they are a noticeable presence in the room because of their size. I’m sure you’ll love the sound.
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- John F on Feb 20, 2020
- Purchased on Aug 3, 2019
BEST ANSWER: As far as sound I’d say no. I think one will be great in that size space. I would suggest measuring and mocking up the physical space it’ll take up. These are large subs. I measured around my previous subs and thought they would be perfect. They seemed much larger when they arrived. I love them but they are a noticeable presence in the room because of their size. I’m sure you’ll love the sound.
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- John F on Feb 20, 2020
- Purchased on Aug 3, 2019
I have the 12" in a 12'x 12' dedicated gaming room with 65" OLED and associated H/T gear. For me, the question was, would the 15" be too big. I rightfully settled on the 12" and glad I did. It is a true beast, serving as a discrete end-table. Never had anything but joy on ultimately selecting this size. Room gain in smaller rooms like this is considerable.
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- William O on Feb 21, 2020
- Purchased on Feb 26, 2019
How tall is the room? You need to know the cubic feet. Honestly I would say go for it. Unless you are married. She won't be super happy. However, the 10" option would probably be more than enough.
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- Matt H on Feb 20, 2020
- Purchased on Nov 29, 2019
No, would be perfect for a room that size. The better question is, what kind of bedroom needs a subwoofer?
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- Nick K on Feb 20, 2020
- Purchased on Apr 13, 2019
Is a McLaren too fast for a public highway? Yes it is overkill but to each their own.
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- Reinier R on Feb 20, 2020
- Purchased on Apr 29, 2019
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Will two monolith 12” subwoofers out perform one monolith 15?
Michael Gautreaux
on Jan 8, 2021
BEST ANSWER: The 15" under benchmarks can get down to 12.5Hz range, whereas the 12 can only get as low as 16 hz.
That being said, two subs evenly distribute base throughout your room better than one sub.
I personally went with two 12" Monolith 500-Watts and they perform exceptionally good.
Just a word of caution: Hooking two 12" subs on the same 15 amp electric circuit is not sufficient. They wont both run. So you need two 15 amp circuits or a single larger circuit (e.g. 20 or 30 amp).
Chris
That being said, two subs evenly distribute base throughout your room better than one sub.
I personally went with two 12" Monolith 500-Watts and they perform exceptionally good.
Just a word of caution: Hooking two 12" subs on the same 15 amp electric circuit is not sufficient. They wont both run. So you need two 15 amp circuits or a single larger circuit (e.g. 20 or 30 amp).
Chris
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- CHRISTOPHER S on Jan 8, 2021
- Purchased on Sep 8, 2020
BEST ANSWER: The 15" under benchmarks can get down to 12.5Hz range, whereas the 12 can only get as low as 16 hz.
That being said, two subs evenly distribute base throughout your room better than one sub.
I personally went with two 12" Monolith 500-Watts and they perform exceptionally good.
Just a word of caution: Hooking two 12" subs on the same 15 amp electric circuit is not sufficient. They wont both run. So you need two 15 amp circuits or a single larger circuit (e.g. 20 or 30 amp).
Chris
That being said, two subs evenly distribute base throughout your room better than one sub.
I personally went with two 12" Monolith 500-Watts and they perform exceptionally good.
Just a word of caution: Hooking two 12" subs on the same 15 amp electric circuit is not sufficient. They wont both run. So you need two 15 amp circuits or a single larger circuit (e.g. 20 or 30 amp).
Chris
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- CHRISTOPHER S on Jan 8, 2021
- Purchased on Sep 8, 2020
Hi mike I prefer two of the 12s for my room because I believe it gives good balance of Base with one on the left front and one on the right front and I’ll be honest with you because my room being 14 x 24 one of these THX 12s would’ve been enough I can only imagine what the 15 with a 1000 watts is like, if you’re short on space the 12 mite be the way to go, the Cabinet for my 12s are pretty big so you’re going to have to figure in we’re to put it I hope this helps you out Mike
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- Dana W on Jan 8, 2021
- Purchased on Oct 17, 2020
Typical math What argue that two 12s well approximately equal one 15. You will get approx a 3db gain by doubling the cone size and 3db by doubling wattage. Those don't add linearly so you should see 4-5db gain.
The benefit of two 12s is smoothing out the peaks and nulls. The benefit of the 15 is more output at lower octaves.
Hopefully that answers your question.
The benefit of two 12s is smoothing out the peaks and nulls. The benefit of the 15 is more output at lower octaves.
Hopefully that answers your question.
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- Donald P on Jan 8, 2021
- Purchased on Nov 27, 2020
in terms of basic area involved I would say yes, you have a total of 24" of cone over a much wider area of sound field, granted the 15 has more power, but the 12's are quite impressive on thier own, even more so with 2 of them.
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- Kenneth A on Jan 8, 2021
- Purchased on Aug 31, 2020
Yes! Mainly because you'll have a 3 to 6 dB gain with two. I have two myself. In no way do I feel it lacking. These subs are devastating! I would say buy two and don't look back.
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- Bob L on Jan 9, 2021
- Purchased on Sep 25, 2020
Good question I only have one 12” and it’s definitely nice. If I were you I’d probably get a 15” now and possibly another down the line
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- Fedor K on Jan 8, 2021
- Purchased on Aug 29, 2020
Short answer yes, two will always be better then one.
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- Matthew S on Jan 9, 2021
- Purchased on May 20, 2020
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Why are the 10" and 12" monolith thx subwoofer rated at the same 500 watts RMS ? I would think the 12" would be rated at a much higher wattage than the 10". Can someone please give a good explanation for that? Thanks
A shopper
on Sep 30, 2018
BEST ANSWER: Because they use the same amplifier.
At the same power the larger woofer still has more displacement, which means lower response and more output.
At the same power the larger woofer still has more displacement, which means lower response and more output.
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- kevin o on Oct 1, 2018
- Purchased on May 20, 2018
BEST ANSWER: Because they use the same amplifier.
At the same power the larger woofer still has more displacement, which means lower response and more output.
At the same power the larger woofer still has more displacement, which means lower response and more output.
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- kevin o on Oct 1, 2018
- Purchased on May 20, 2018
Refer to the measurements given at the bottom of each product listings. The 12" model has much more output than the 10" model. The goal in buying a subwoofer is the getting the most low-distortion output. The details of the amplifier, etc., are interesting, but not really relative to the purchase decision.
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- Jeff S on Nov 15, 2018
I don't think you will notice the difference,,, if you have a small room get the 10 inch! The 12" is big and extremely heavy!!
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- New User U on Oct 19, 2018
- Purchased on Oct 15, 2018
500 watts is plenty to drive whatever woofer you want. The 10 will not have the output of the 12 even with same power rating.
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- New User U on Sep 30, 2018
- Purchased on Nov 7, 2017
Enclose size . More cabinet more pressure and air for driver
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- john s on Sep 30, 2018
- Purchased on Jun 8, 2018
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Would this sub be enough for a 17x17 living room (not sealed)? Or should I get the 15 inch model instead?
New User U
on Feb 6, 2019
BEST ANSWER: The 12" will do just fine for that size room.
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- New User U Staff on Feb 6, 2019
BEST ANSWER: The 12" will do just fine for that size room.
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- New User U Staff on Feb 6, 2019
It will be plenty I assure you! I just installed in my 15x19 room and it’s overwhelming when cranked up
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- Corey B on Feb 6, 2019
- Purchased on Jan 26, 2019
Thank you!
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- New User U on Feb 6, 2019
assuming you have 8 foot high ceilings, your room would be about 2300 cubic feet. this sub is thx certified up to 3000 cubic feet so i think it would be plenty
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- New User U on Jan 19, 2021
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When I turn off the subwoofer, the on light stays on for 30 seconds. Also, after the unit has been on and then the signal is turned off for a period, when the signal is turned back on the unit has to be powered off/on for it to pick up the signal again. Is this common?
morgan d
on Jul 1, 2020
BEST ANSWER: Stop turning the subwoofer off. It automatically will go into stand by after it detects no signal. You dont keep turning the subwoofer on and off.
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- Inaccurate
- Brian K on Jul 1, 2020
- Purchased on Dec 21, 2019
BEST ANSWER: Stop turning the subwoofer off. It automatically will go into stand by after it detects no signal. You dont keep turning the subwoofer on and off.
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- Brian K on Jul 1, 2020
- Purchased on Dec 21, 2019
Morgan, are you manually turning the subwoofer on and off by means of the power toggle or the main power switch?
If you turn off the amp it will go through a powering off process which takes around 30 sec to 1 min.
Do you have the rear power toggle on auto/on/or off?
If you turn off the amp it will go through a powering off process which takes around 30 sec to 1 min.
Do you have the rear power toggle on auto/on/or off?
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- New User U on Jul 1, 2020
- Purchased on Dec 3, 2019
I'm only manually turning the power off with the power switch when the subwoofer does not come out of standby mode. Cycling the power brings it out of standby. Toggle set on auto.
What equipment is the subwoofer connected to?
How do you have it connected?
What cables are you using?
How do you have it connected?
What cables are you using?
- Reply (1)
- New User U on Jul 1, 2020
It's connected to yamaha rx-a2080 receiver via this cable sold on Amazon KabelDirekt RCA Subwoofer Cable, Cord (20 feet Long, 1 RCA Male to 1 RCA Male Audio Video Cable, Digital & Analogue, Double Shielded, Pro Series) Supports (Subwoofers, AV Receivers, Hi-Fi)
Ok. Have you tried putting the subwoofer power toggle on “auto” and In your receiver settings put the dB higher for the subwoofer?
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- New User U on Jul 2, 2020
Also, I run my sub slightly higher due to room size. My other sub will kick on before my monolith sub turns on. The sub will measure a quick sound compared to consistent sound of a movie or music. I sometimes have to allow 5-10 seconds of consistently louder portions of a movie before the sun will turn itself on.
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- New User U on Jul 2, 2020
Yes, my is behaving the same way, its normal, just takes getting use to it. Mine takes almost a month for it to be fully break in to sound great and full. This is different from all the subs that I had before, once you are use to the clean sound, you will love it.
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- Leng C on Jul 1, 2020
- Purchased on Jan 21, 2020
The light usually stays on like that, although I barely turn it off . It has happened to mine a few times where I have to turn it off then back on, but not that often.
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- Kyle K on Jul 1, 2020
- Purchased on Dec 8, 2019
No this is not common. Seems to be a technical issue with the subwoofer.
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- Malik I on Jul 1, 2020
- Purchased on Jul 21, 2019
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what does flashing green power light mean?
Ronald W
on Apr 8, 2021
BEST ANSWER: The sub is not receiving any signal from the receiver. My reciever timed out and turned itself off without my knowledge and threw me for a good half an hour of troubleshooting. Once I turned the receiver back on, it turned to a solid green.
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- Rado G on Apr 8, 2021
- Purchased on Mar 1, 2021
BEST ANSWER: The sub is not receiving any signal from the receiver. My reciever timed out and turned itself off without my knowledge and threw me for a good half an hour of troubleshooting. Once I turned the receiver back on, it turned to a solid green.
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- Rado G on Apr 8, 2021
- Purchased on Mar 1, 2021
I think it means the sub is changing modes..ie...turning on or turning off. It should then go to a solid green or a slid red light
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- Warren T on Apr 8, 2021
- Purchased on Mar 18, 2021
The unit is entering a wake up mode and will go to solid green when in use
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- Inaccurate
- ROBERT D on Apr 8, 2021
- Purchased on Mar 20, 2021
It's on and waiting for a signal.
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- Matthew R on Apr 8, 2021
- Purchased on Mar 17, 2021
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Can you please provide specifications in terms of power requirements for a North American household? I'd like to run 2 of these in my home theater currently under construction and want to know if I can run them both on the same dedicated 15 A circuit... or if I need to run them both on a dedicated 20 A circuit. Thanks!
A shopper
on Oct 27, 2017
BEST ANSWER: I'm an E..E. for whatever that's worth. The units likely will run fine on a 15A circuit. However, a 20A circuit will only cost a little extra for the wire (you'll need #12 instead of #14 Romex) and nothing extra for the breaker or the outlet. A 20A 120V outlet will take either a 20A or 15A plug. There will be less voltage drop in the circuit with larger wire and you'll not wonder over the years if you should have spent another $25 and gotten a larger circuit. If the electrical service panel isn't very far away from the new room, and there are spaces in the panel for extra breakers, then it doesn't cost much extra to run extra circuits, or higher capacity circuits when you are building a room. It will cost a lot more to add circuits in the future.
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- Kay S on Nov 15, 2018
- Purchased on Sep 25, 2018
BEST ANSWER: I'm an E..E. for whatever that's worth. The units likely will run fine on a 15A circuit. However, a 20A circuit will only cost a little extra for the wire (you'll need #12 instead of #14 Romex) and nothing extra for the breaker or the outlet. A 20A 120V outlet will take either a 20A or 15A plug. There will be less voltage drop in the circuit with larger wire and you'll not wonder over the years if you should have spent another $25 and gotten a larger circuit. If the electrical service panel isn't very far away from the new room, and there are spaces in the panel for extra breakers, then it doesn't cost much extra to run extra circuits, or higher capacity circuits when you are building a room. It will cost a lot more to add circuits in the future.
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- Kay S on Nov 15, 2018
- Purchased on Sep 25, 2018
15A will likely work. During the construction phase changing to a 20A circuit will only add a little cost for the wire (go to #12 from #14). The circuit breaker and the outlet will cost the same. The 20A outlet will support both 15A or 20A plugs. It makes good sense to spend what should be $25 extra or so to go with the 20A circuit.
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- Jeff S on Nov 15, 2018
I has a 20 amp circuit put in for this sub and a 12" SVS sub.
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- New User U on Dec 11, 2017
- Purchased on Nov 7, 2017
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Hello. I just looked at the manual and it appears the 10” goes lower than the 12 according to the manual. Is this correct?
New User U
on Nov 8, 2017
BEST ANSWER: The 12" subwoofer goes lower and plays louder, as a 12" should. The Monolith 12" subwoofer has a 4 to 6 dB advantage over the 10" at 16Hz and 20Hz.
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- New User U Staff on Nov 8, 2017
Thank you for the answer.
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- New User U on Nov 8, 2017
BEST ANSWER: The 12" subwoofer goes lower and plays louder, as a 12" should. The Monolith 12" subwoofer has a 4 to 6 dB advantage over the 10" at 16Hz and 20Hz.
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- Inaccurate
- New User U Staff on Nov 8, 2017
Thank you for the answer.
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- New User U on Nov 8, 2017
Go to the Monoprice webpage. Go to the Monolith subwoofers. Access the 10" Monolith sub in one window, the 12" Monolith sub in another separate instance of your browser. Place the two windows side by side. Go to the bottom of each page. You will see the measurements of the two subs. You'll see that the 12" sub has more output than the 10" sub at all frequencies, ported and sealed.
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- Jeff S on Nov 15, 2018
Refer to the measurements given at the bottom of each of the product listings. The 12" model has much more output than the 10" model at all frequencies and with all port configurations.
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- Jeff S on Nov 15, 2018
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is this 220v?
A shopper
on Feb 25, 2020
BEST ANSWER: Thank you for your question.
No this product is not compatible with 220v power.
No this product is not compatible with 220v power.
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- Inaccurate
- Tyler C Staff on Feb 25, 2020
BEST ANSWER: Thank you for your question.
No this product is not compatible with 220v power.
No this product is not compatible with 220v power.
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- Tyler C Staff on Feb 25, 2020
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My led power indicator is flashing red and green and will not turn on. What is the cause of this??
William L
on Sep 11, 2020
BEST ANSWER: The amp has to reset, try unplugging the power cord from the back until the light stops flashing and plug it back in and wait for the light to turn solid green
- Reply(1)
- Inaccurate
- Matthew S on Sep 12, 2020
- Purchased on May 20, 2020
BEST ANSWER: The amp has to reset, try unplugging the power cord from the back until the light stops flashing and plug it back in and wait for the light to turn solid green
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- Inaccurate
- Matthew S on Sep 12, 2020
- Purchased on May 20, 2020
It only flashes red and green when turning it on off with subwoofer switch. Put it in auto and leave the subwoofer on.
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- Inaccurate
- Brian K on Sep 12, 2020
- Purchased on Dec 21, 2019
Something inside the sub's fuse setup flipped and didn't go back. Usually occurs if your power goes out and comes back on rapidly. Mine has done it a few times. I just unplugged it from the wall for a few minutes and then after I plugged it back in everything was back to normal. Hope this helps.
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- jamie m on Sep 11, 2020
- Purchased on Jan 20, 2020
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THX rating says this is acceptable for a 3000 cu ft room with 10-12' viewing distance. My room is 3200 cu ft. What if I want 2 subs? Can I drop down to the 10" subs?
New User U
on Oct 29, 2021
BEST ANSWER: I have two of the 12" Ultras in my home theater. The screen wall if you will is 16ft.across and 37ft deep with a 9 ft screen. I have a cabinet below the screen that is 66" wide with a sub on each end that leaves approximately 4 ft to the side walls,
I had a couple of Energy AS-180 for years and I found the Ultras had a fuller sound, more range. and more dynamic.. I like the the look and suits my needs but I had wonder if a single 15" might have served better for a couple hundred dollars less. It all depends on the aesthetics and the room you have available. I'm still impressed with my results.
On a side note I run Infinity Kappas and just received the Monolith Amp and really woke up those Kappas, I'm running a Denon 4400h and just didn't have the punch. It might something to consider to add to your system. Hope this helps Robert
I had a couple of Energy AS-180 for years and I found the Ultras had a fuller sound, more range. and more dynamic.. I like the the look and suits my needs but I had wonder if a single 15" might have served better for a couple hundred dollars less. It all depends on the aesthetics and the room you have available. I'm still impressed with my results.
On a side note I run Infinity Kappas and just received the Monolith Amp and really woke up those Kappas, I'm running a Denon 4400h and just didn't have the punch. It might something to consider to add to your system. Hope this helps Robert
- Reply
- Inaccurate
- ROBERT D on Nov 2, 2021
- Purchased on Mar 20, 2021
BEST ANSWER: I have two of the 12" Ultras in my home theater. The screen wall if you will is 16ft.across and 37ft deep with a 9 ft screen. I have a cabinet below the screen that is 66" wide with a sub on each end that leaves approximately 4 ft to the side walls,
I had a couple of Energy AS-180 for years and I found the Ultras had a fuller sound, more range. and more dynamic.. I like the the look and suits my needs but I had wonder if a single 15" might have served better for a couple hundred dollars less. It all depends on the aesthetics and the room you have available. I'm still impressed with my results.
On a side note I run Infinity Kappas and just received the Monolith Amp and really woke up those Kappas, I'm running a Denon 4400h and just didn't have the punch. It might something to consider to add to your system. Hope this helps Robert
I had a couple of Energy AS-180 for years and I found the Ultras had a fuller sound, more range. and more dynamic.. I like the the look and suits my needs but I had wonder if a single 15" might have served better for a couple hundred dollars less. It all depends on the aesthetics and the room you have available. I'm still impressed with my results.
On a side note I run Infinity Kappas and just received the Monolith Amp and really woke up those Kappas, I'm running a Denon 4400h and just didn't have the punch. It might something to consider to add to your system. Hope this helps Robert
- Reply
- Inaccurate
- ROBERT D on Nov 2, 2021
- Purchased on Mar 20, 2021
The THX Select rating of the 10" model shows a room size of 2000 ft.³.. According to that metric, dual 10" subwoofers should be sufficient for a 3200 ft³. room. If aesthetics and maneuverability are a concern, the 10" model will also be an easier fit. If it is a choice between dual 10" units and a single 12" unit, you may want to consider going with a dual setup. If implemented properly, multiple subwoofer setups can more evenly distribute bass energy in a room than a single unit.
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- powderhound00 on Nov 2, 2021
- Purchased on Mar 19, 2021
You are better off with two of the 12" units
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- Warren T on Nov 2, 2021
- Purchased on Nov 1, 2021
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I'm just wondering if there are threaded inserts on the bottom of the sub for spikes etc? I'd be interested in adding the svs sounpath isolation feet.
A shopper
on Mar 11, 2018
BEST ANSWER: Yes, there are threaded steel inserts.
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- New User U Staff on Mar 12, 2018
BEST ANSWER: Yes, there are threaded steel inserts.
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- New User U Staff on Mar 12, 2018
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Are the feet removable? if so, are they the screw on type or adhesive?
kevin o
on May 19, 2018
BEST ANSWER: The feet are removable, and they are screw on.
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- New User U Staff on May 21, 2018
BEST ANSWER: The feet are removable, and they are screw on.
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- New User U Staff on May 21, 2018
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Will the subwoofer run on 220v electricity?
A shopper
on Feb 3, 2019
Check the back power toggle . I believe it has that option . If you don’t see toggle it is 210
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- john s on Feb 3, 2019
- Purchased on Jun 8, 2018
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Whats the difference between this monolith 12 ported and the sealed as far as performance? Thanks
A shopper
on Nov 29, 2019
BEST ANSWER: The output data is listed on both of the products to make it easy to compare.
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- New User U Staff on Nov 29, 2019
BEST ANSWER: The output data is listed on both of the products to make it easy to compare.
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- New User U Staff on Nov 29, 2019
The ported lends itself more towards home theater. Digs deeper in 20-40hz range where it counts. Remember you use the port plugs too and run in “sealed” mode too. It’s a much larger cabinet too. But if the size of sub is not an issue for living space. The ported gives you the ultimate flexibility for music or theater.
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- New User U on Nov 29, 2019
- Purchased on Nov 18, 2019
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Is there any way to wirelessly connect the subwoofers to receiver? Something like svs soundpath?
Gunjan M
on May 26, 2020
Yes if you connect a wireless transmitter to the your avr and the accompanying receiver to the sub. Something similar to Rel or Outlaw Audio or Emotiva.... SVS may have one also
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- New User U on Nov 1, 2021
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My living room doesnt have a ton of extra space but I want to run dual subs. Would stacking two 12 inch subs be an issue?
New User U
on Jul 31, 2020
BEST ANSWER: No it wont be a problem. if that is your only option for running two subs that will be just fine. In fact you will live it. It will give great bass in more area of your room.
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- Brian K on Aug 1, 2020
- Purchased on Dec 21, 2019
BEST ANSWER: No it wont be a problem. if that is your only option for running two subs that will be just fine. In fact you will live it. It will give great bass in more area of your room.
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- Brian K on Aug 1, 2020
- Purchased on Dec 21, 2019
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Can you add maximum SPL in the various modes (THX, etc.) to the spec sheets for all of these new subwoofers? Thanks!
Jason G
on Sep 2, 2017

Monolith by Monoprice 12in THX Certified Ultra 500-Watt Subwoofer Amplifier

Monolith by Monoprice 10in THX Certified Select Subwoofer Amplifier

Monolith by Monoprice 15in THX Certified Ultra 1000-Watt Subwoofer Amplifier
BEST ANSWER: We will be adding CEA-2010 @2M burst and RMS measurements by frequency in the near future.
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- New User U Staff on Sep 5, 2017
BEST ANSWER: We will be adding CEA-2010 @2M burst and RMS measurements by frequency in the near future.
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- New User U Staff on Sep 5, 2017
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Can these sub woofers be positioned on their side for a lower profile? I have a large projection screen and plan on placing two subs up front.
Shawn P
on Oct 29, 2017
BEST ANSWER: Yes, you can lay the subwoofer on its side with no loss in performance.
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- New User U Staff on Oct 30, 2017
BEST ANSWER: Yes, you can lay the subwoofer on its side with no loss in performance.
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- New User U Staff on Oct 30, 2017
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Are the in-house CEA-2010 numbers listed in THX mode or Extended mode?
A shopper
on Mar 4, 2018

Monolith by Monoprice 12in THX Certified Ultra 500-Watt Subwoofer Amplifier

Monolith by Monoprice 10in THX Certified Select Subwoofer Amplifier

Monolith by Monoprice 15in THX Certified Ultra 1000-Watt Subwoofer Amplifier
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Can you tell me the size of the threaded inserts on the bottom of the sub?
A shopper
on Mar 23, 2018
BEST ANSWER: M6-1.00 (course thread) 20-25mm long machine screws depending on your application. For feet, Reliable Hardware Company RH-1606-8-A Guitar Amplifier Cabinet feet (1-pack of 8) work fine.
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- Dennis R on Oct 14, 2018
BEST ANSWER: M6-1.00 (course thread) 20-25mm long machine screws depending on your application. For feet, Reliable Hardware Company RH-1606-8-A Guitar Amplifier Cabinet feet (1-pack of 8) work fine.
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- Dennis R on Oct 14, 2018
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Are there any issues with placing the subs on their side? The THX 12 and THX 15 height will get too close interfere with my screen and make reflections. Particular concern of amplifier air flow and over heats?
A shopper
on May 14, 2018

Monolith by Monoprice 12in THX Certified Ultra 500-Watt Subwoofer Amplifier

Monolith by Monoprice 10in THX Certified Select Subwoofer Amplifier

Monolith by Monoprice 15in THX Certified Ultra 1000-Watt Subwoofer Amplifier
BEST ANSWER: No issues, you can place the subwoofer on its side.
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- New User U Staff on May 15, 2018
BEST ANSWER: No issues, you can place the subwoofer on its side.
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- New User U Staff on May 15, 2018
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Will these ever be available to buy again? Been waiting since late June and eta keeps getting pushed back?
A shopper
on Aug 6, 2018
BEST ANSWER: Yes, these should be arriving in mid to late September.
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- New User U Staff on Aug 6, 2018
BEST ANSWER: Yes, these should be arriving in mid to late September.
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- New User U Staff on Aug 6, 2018
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Does this have a 12V monaural mini plug Trigger jack for automatically turning on and off automatically when the receiver is turned off?
A shopper
on Sep 17, 2018
BEST ANSWER: Thank you for your question.
Currently we do not sell trigger cables.
Currently we do not sell trigger cables.
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- Tyler C Staff on May 22, 2019
BEST ANSWER: Thank you for your question.
Currently we do not sell trigger cables.
Currently we do not sell trigger cables.
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- Tyler C Staff on May 22, 2019
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More photos? Especially with grill on?
A shopper
on Oct 4, 2018
BEST ANSWER: You can see photos at Audioholics.com or avsforum.com
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- New User U Staff on Oct 4, 2018
BEST ANSWER: You can see photos at Audioholics.com or avsforum.com
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- New User U Staff on Oct 4, 2018
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230VAC, 50Hz workable?
A shopper
on Oct 7, 2018
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What is the total weight and dimensions of the box this comes in? I want to get an estimate from my freight forwarder to ship to Hawaii.
New User U
on Jan 16, 2019
BEST ANSWER: Weight: 103lbs Box Dimensions: 33x22x30.5
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- New User U Staff on Jan 16, 2019
BEST ANSWER: Weight: 103lbs Box Dimensions: 33x22x30.5
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- New User U Staff on Jan 16, 2019
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Where near San Francisco can I hear it?
Ivan B
on Mar 31, 2019

Monolith by Monoprice 12in THX Certified Ultra 500-Watt Subwoofer Amplifier

Monolith by Monoprice 10in THX Certified Select Subwoofer Amplifier

Monolith by Monoprice 10" THX Select Certified 500 Watt Powered Subwoofer (Open Box)

Monolith by Monoprice 12" THX Ultra Certified 500 Watt Powered Subwoofer (Open Box)
BEST ANSWER: Thank you for your question.
We would not offer a place to get a live demonstration of our subwoofers.
We would not offer a place to get a live demonstration of our subwoofers.
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- Tyler C Staff on Sep 3, 2019
BEST ANSWER: Thank you for your question.
We would not offer a place to get a live demonstration of our subwoofers.
We would not offer a place to get a live demonstration of our subwoofers.
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- Tyler C Staff on Sep 3, 2019
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Is the grille made from steel or a hardened material to prevent damaging the woofer?
A shopper
on May 21, 2019
BEST ANSWER: The grille is cloth, and I'm not sure who or what you would need to protect the woofer from.
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- New User U Staff on May 21, 2019
BEST ANSWER: The grille is cloth, and I'm not sure who or what you would need to protect the woofer from.
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- New User U Staff on May 21, 2019
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Reviews
4.9 / 5.0
76 Reviews
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Rated 5 out of 5
After a few months of ownership.
Sooooooooo Wow.... i was in the market for the Thx15 but i missed the clearance deal when the new models came out at the end of the year. So i settled on the 12 since they were still in stock even though i was concerned about the much lower rms power rating of 500 Watts... Ended up being the perfect match for my current setup, i think the 15 would have been way overkill. Very satisfied so far.
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Rated 5 out of 5
Large and in charge.
Subwoofer sounds great. Super clear low end frequency. Unit is quite large. Was kinda shocked initially how large it is. Almost like an end table. That said, it looks very nice.
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Rated 5 out of 5
Clean room filling bass!
Very high quality for the price. Room filling base that is very clear. Not muddy. Very even response curve from across frequencies.
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Rated 5 out of 5
You didn't know what you were missing!
It's abit larger and heavier than I had imagined, it also uses wording on the switches and knobs that are not the same as your basic $100-$300 Sub from mainstream companies. With that said once you dive in and get everything set properly you have a fantastic sub that will show you just what you have been missing!

Added Jan 31, 2022
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Rated 5 out of 5
One of the best purchases that I have bought for my theater room. Bought 2 of them and they definitely out perform the other subwoofers I have had in the past! Love the sound and the response I receive from the 12 inch subs.

Added Jan 28, 2022
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Rated 5 out of 5
ABSOLUTE BEAST!!
I am thrilled with my purchase. This subwoofer makes home theater so much better, with it's low guttural growls, and earth shattering explosions! It is by far my most favorite addition to my system. Way to go Monoprice, way to go!
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Rated 5 out of 5
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Rated 5 out of 5
Massively smooth output. Game changing system performance.
I ordered two Version 1 units prior to Xmas ?21 during the closeout sale as part of a HT update. Being knee deep in the global supply situation, I wasn?t waiting. Size and specs are very equal to the new V2, so the discounted price couldn?t be beat. Research narrowed the list down to Monolith, SVS, and REL. Primary listening is HT, but also wanted a sub that could perform musically. My front stage is B&W 804?s powered by Emotiva XPA and Basx AMPS (part of the HT update). I was upgrading from a set of 10? Klipsch?s that simply could no longer handle the reference volume levels I was listening too. Plus, they were at the end of their life and starting to ?fall a part?, literally. I also wanted something that would provide impact at low volume levels.
The reviews on the Monolith line have been highly positive so I took the leap. And I am not disappointed. Just a word of caution, no set of measurements on paper will prepare you for how big these are. They are double box packed with Styrofoam, very well packed. And they need it since FedEx will throw these around.
Positives:
1.Value
2.Performance in HT and Music.
3.Control ? at the moment I use my Pre Amp and the Sub Controls. I may add a MINIDSP later for fine tuning.
4.Output and head room. They will rumble the room with volume but are truly fantastic @ low levels. Currently, I run them ported and have not had much time to experiment with the dual port plugs. I like the sound. So far, no chuffing in my set up since I run the level on the sub @ 0 db. I know some review suggest boosting this up to + 5 db, but I haven?t done too much tuning since this is such an improvement from where I was.
5.Bass blends away with 2 or more units. This is really key. Don?t tell the wife, but I would add 2 more (for music I would only run 2). Do not underestimate the impact quality subwoofers will have on the overall system performance. I was a skeptic on this comment, but no more!
Negatives:
1.Size. WAF factor is medium low at best. Triple check the measurements.
2.Heavy, but what do you expect. HDF with a massive driver. Furniture mover feet are your friends or a second person are your friends.
3.The rubber feet will leave a black marks on solid surfaces.
The reviews on the Monolith line have been highly positive so I took the leap. And I am not disappointed. Just a word of caution, no set of measurements on paper will prepare you for how big these are. They are double box packed with Styrofoam, very well packed. And they need it since FedEx will throw these around.
Positives:
1.Value
2.Performance in HT and Music.
3.Control ? at the moment I use my Pre Amp and the Sub Controls. I may add a MINIDSP later for fine tuning.
4.Output and head room. They will rumble the room with volume but are truly fantastic @ low levels. Currently, I run them ported and have not had much time to experiment with the dual port plugs. I like the sound. So far, no chuffing in my set up since I run the level on the sub @ 0 db. I know some review suggest boosting this up to + 5 db, but I haven?t done too much tuning since this is such an improvement from where I was.
5.Bass blends away with 2 or more units. This is really key. Don?t tell the wife, but I would add 2 more (for music I would only run 2). Do not underestimate the impact quality subwoofers will have on the overall system performance. I was a skeptic on this comment, but no more!
Negatives:
1.Size. WAF factor is medium low at best. Triple check the measurements.
2.Heavy, but what do you expect. HDF with a massive driver. Furniture mover feet are your friends or a second person are your friends.
3.The rubber feet will leave a black marks on solid surfaces.
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Rated 5 out of 5
Great product
Very happy with the price, quick shipping and overall hi quality of this subwoofer. Sounds great and haven't even dialed it in all the way. So glad I came across this subwoofer from the forums and YouTube test videos against subs that cost twice as much. Thank you Monoprice/Monolith

Added Jan 12, 2022
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Rated 5 out of 5
Wow, this Sub is super impressive. Only had a few weeks, but so far has performed amazingly. The response is accurate and deep. Placement is key, as is the room size. She is a monster. Will be looking to purchase another very soon.
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