Monolith by Monoprice THX-465IW THX Certified Ultra 3-Way In-Wall Speaker
Product # 42829
UPC # 889028170229
$699.99
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Browse 23 questions
Browse 23 questions
and 14 answers
Can this speaker be used horizontally for the center and vertically for the L and R?
A shopper
on Apr 2, 2023
BEST ANSWER: I suppose you could install this speaker Horizontally as a center. Keep in mind that this would require extensive effort. This speaker when placed horizontally is almost 3 feet across. This would require cutting studs and then building a header to carry the load of the wall. Something that would be difficult in a load barring wall. I have this vertically installed between studs behind an acoustically transparent screen. For the best front stage you really want all three speakers on the same plane with tweeters aligned.
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- MICHAEL M on Apr 14, 2023
- Purchased on Feb 3, 2023
BEST ANSWER: I suppose you could install this speaker Horizontally as a center. Keep in mind that this would require extensive effort. This speaker when placed horizontally is almost 3 feet across. This would require cutting studs and then building a header to carry the load of the wall. Something that would be difficult in a load barring wall. I have this vertically installed between studs behind an acoustically transparent screen. For the best front stage you really want all three speakers on the same plane with tweeters aligned.
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- MICHAEL M on Apr 14, 2023
- Purchased on Feb 3, 2023
That is exactly how I have them mounted - 3 of these for LCR
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- Kitchenboy on Apr 14, 2023
- Purchased on Feb 19, 2023
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Is this in-wall speaker Ultra Certified as an LCR or only as a Surround speaker? Thank you.
A shopper
on Jan 7, 2022
BEST ANSWER: The speaker is Ultra Certified regardless it's used. However, the speaker wasn't designed for use as a surround speaker. The reason is it includes substantial bass capability and abillity to project bass at reference sound levels whereas surround sound speakers typically do not require this capabilitiy. Additionally, this speaker is large in size which most users would consider undesirable in a speaker used to project only surround sound. Nonetheless, this speaker would perform well as a surround speaker although the majority of listeners would consider use for this purpose as superflous.
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- Thomas H on Jan 20, 2022
BEST ANSWER: The speaker is Ultra Certified regardless it's used. However, the speaker wasn't designed for use as a surround speaker. The reason is it includes substantial bass capability and abillity to project bass at reference sound levels whereas surround sound speakers typically do not require this capabilitiy. Additionally, this speaker is large in size which most users would consider undesirable in a speaker used to project only surround sound. Nonetheless, this speaker would perform well as a surround speaker although the majority of listeners would consider use for this purpose as superflous.
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- Thomas H on Jan 20, 2022
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When will these be ready
Waiting on these the minute there are three available please let me know?
Waiting on these the minute there are three available please let me know?
A shopper
on May 20, 2022
BEST ANSWER: If you signed up to be on the waiting list, you will be notified when these come into stock.
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- New User U Staff on May 20, 2022
BEST ANSWER: If you signed up to be on the waiting list, you will be notified when these come into stock.
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- New User U Staff on May 20, 2022
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What is the maximum thickness of the wall material that the mounting brackets on the THX-465IW will accommodate?
A shopper
on Aug 7, 2022
BEST ANSWER: The max wall thickness to clamp is 1.5” plus a taste to ensure 1.5” can be cleared.
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- New User U Staff on Aug 24, 2022
BEST ANSWER: The max wall thickness to clamp is 1.5” plus a taste to ensure 1.5” can be cleared.
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- New User U Staff on Aug 24, 2022
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I have to “stud out” a horizontal opening with 2x4’s. What would be the ideal size for this speaker?
STEPHEN L
on Aug 7, 2022
BEST ANSWER: This speaker is designed for an infinite baffle wall. If you turn it horizontal and create a space for it Your open space will be Y axis vertical along the long side of the horizontal speaker. You can make this a comfortable size, I suggest about 8“ above and below to a supporting cross brace to give the drywall support near the speaker.
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- New User U Staff on Aug 24, 2022
BEST ANSWER: This speaker is designed for an infinite baffle wall. If you turn it horizontal and create a space for it Your open space will be Y axis vertical along the long side of the horizontal speaker. You can make this a comfortable size, I suggest about 8“ above and below to a supporting cross brace to give the drywall support near the speaker.
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- New User U Staff on Aug 24, 2022
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See Background below for some context.
Questions: Q1 - Is it ok to have THX-465IW speaker 1" above a horizontal stud and 1" below horizontal studs and almost flush with L/R framing studs (a) for the installation tabs and (b) for sound? Q2 - is there a need to have anything behind the speaker or is it OK for it to empty out onto the fireplace cavit (see below). Q3 - what are the recommended Front LR, and Rear LR and surround and atmos speakers to complement this center channel?
Background: I am in the middle of a family / dining room remodel. Room is 28x16 with the center channel location approx 12' from the RHS of the long wall. Besides the kitchen, this is the only shared space in our house so this is where we are putting the "home theater". WAF is paramount and important for me too, so we're gong mostly in-walls with a couple of Heresy 1's on the floor for retro vibe, vinyl playing, and potentially as Front Wide LR (TBD). There is fireplace installed with cool vent (FirePlaceX CoolSmart) heat displacement system to push the heat in a vent up and round the back of the TV in the wall space. This leaves limited space for a center channel speaker but it is doable. We will put a smallish (43") Art TV for casual viewing / ART display and I will make an acoustically transparent screen for movie night, sports games and such, size TBD but likely 80-100" wide for a short throw projector and a seating positions 4' to 10' back from the screen. Fireplace cavity is 5' wide by 8' high by 18" deep cavity. which includes the fireplace, with cut steel plate, and both flex and sheet steel vents.
Questions: Q1 - Is it ok to have THX-465IW speaker 1" above a horizontal stud and 1" below horizontal studs and almost flush with L/R framing studs (a) for the installation tabs and (b) for sound? Q2 - is there a need to have anything behind the speaker or is it OK for it to empty out onto the fireplace cavit (see below). Q3 - what are the recommended Front LR, and Rear LR and surround and atmos speakers to complement this center channel?
Background: I am in the middle of a family / dining room remodel. Room is 28x16 with the center channel location approx 12' from the RHS of the long wall. Besides the kitchen, this is the only shared space in our house so this is where we are putting the "home theater". WAF is paramount and important for me too, so we're gong mostly in-walls with a couple of Heresy 1's on the floor for retro vibe, vinyl playing, and potentially as Front Wide LR (TBD). There is fireplace installed with cool vent (FirePlaceX CoolSmart) heat displacement system to push the heat in a vent up and round the back of the TV in the wall space. This leaves limited space for a center channel speaker but it is doable. We will put a smallish (43") Art TV for casual viewing / ART display and I will make an acoustically transparent screen for movie night, sports games and such, size TBD but likely 80-100" wide for a short throw projector and a seating positions 4' to 10' back from the screen. Fireplace cavity is 5' wide by 8' high by 18" deep cavity. which includes the fireplace, with cut steel plate, and both flex and sheet steel vents.
Julian W
on Sep 18, 2022
BEST ANSWER: Questions: Q1 - Is it ok to have THX-465IW speaker 1" above a horizontal stud and 1" below horizontal studs and almost flush with L/R framing studs (a) for the installation tabs and (b) for sound?
Yes, this is ok.
Q2 - is there a need to have anything behind the speaker or is it OK for it to empty out onto the fireplace cavit (see below).
Is there a radiated heat issue in there? What about the fireplace heat recovery unit itself is it steel that can vibrate under high level listening like a movie with explosions etc? You can fire into an infinite baffle as it is designed for such but be careful what is nearby.
Q3 - what are the recommended Front LR, and Rear LR and surround and atmos speakers to complement this center channel?
Rear 34368
Center – 34366, 34367, 42830
LR – 34366, 34367, 42830
Yes, this is ok.
Q2 - is there a need to have anything behind the speaker or is it OK for it to empty out onto the fireplace cavit (see below).
Is there a radiated heat issue in there? What about the fireplace heat recovery unit itself is it steel that can vibrate under high level listening like a movie with explosions etc? You can fire into an infinite baffle as it is designed for such but be careful what is nearby.
Q3 - what are the recommended Front LR, and Rear LR and surround and atmos speakers to complement this center channel?
Rear 34368
Center – 34366, 34367, 42830
LR – 34366, 34367, 42830
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- Inaccurate
- New User U Staff on Sep 19, 2022
BEST ANSWER: Questions: Q1 - Is it ok to have THX-465IW speaker 1" above a horizontal stud and 1" below horizontal studs and almost flush with L/R framing studs (a) for the installation tabs and (b) for sound?
Yes, this is ok.
Q2 - is there a need to have anything behind the speaker or is it OK for it to empty out onto the fireplace cavit (see below).
Is there a radiated heat issue in there? What about the fireplace heat recovery unit itself is it steel that can vibrate under high level listening like a movie with explosions etc? You can fire into an infinite baffle as it is designed for such but be careful what is nearby.
Q3 - what are the recommended Front LR, and Rear LR and surround and atmos speakers to complement this center channel?
Rear 34368
Center – 34366, 34367, 42830
LR – 34366, 34367, 42830
Yes, this is ok.
Q2 - is there a need to have anything behind the speaker or is it OK for it to empty out onto the fireplace cavit (see below).
Is there a radiated heat issue in there? What about the fireplace heat recovery unit itself is it steel that can vibrate under high level listening like a movie with explosions etc? You can fire into an infinite baffle as it is designed for such but be careful what is nearby.
Q3 - what are the recommended Front LR, and Rear LR and surround and atmos speakers to complement this center channel?
Rear 34368
Center – 34366, 34367, 42830
LR – 34366, 34367, 42830
- Reply
- Inaccurate
- New User U Staff on Sep 19, 2022
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is there a mounting kit for any of the Monolith In-wall speakers? I'm having sheetrock installed, and would rather have the sheetrock guys make the cuts than do that after the fact.
A shopper
on Oct 6, 2022

Monolith by Monoprice THX-465IW THX Certified Ultra 3-Way In-Wall Speaker

Monolith by Monoprice THX-365IW THX Certified Ultra 3-Way In-Wall Speaker

Monolith by Monoprice THX-275IW THX Certified Select 3-Way In-Wall Speaker
BEST ANSWER: We dont have a kit but the cutout dimensions are listed.
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- New User U Staff on Oct 6, 2022
BEST ANSWER: We dont have a kit but the cutout dimensions are listed.
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- New User U Staff on Oct 6, 2022
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I'm trying to plan a HT system. I'm thinking I'll use 3 THX-465IWs (LCR channel), 2 M12-VT (subs), 2 THX-275IWs (in-wall surrounds), and 2 or 4 in-ceiling atmos speakers. Does this setup make sense? And what atmos speakers should use?
TIMOTHY B
on Oct 6, 2022

Monolith by Monoprice THX-465IW THX Certified Ultra 3-Way In-Wall Speaker

Monolith by Monoprice THX-365IW THX Certified Ultra 3-Way In-Wall Speaker

Monolith by Monoprice THX-275IW THX Certified Select 3-Way In-Wall Speaker

Monolith by Monoprice M-12 V2 12in THX Certified Ultra 500-Watt Powered Subwoofer
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I currently have Martin Logan’s Motion 12s (towers) for my left and right, and looking to purchase in walls. I’m wondering if the THX 465IW would be a good replacement for my surround sound. Can the THX 465IW match my Martin Logan’s?
A shopper
on Apr 19, 2023
BEST ANSWER: These may not blend well with the Motion 12's due to the folded motion tweeter.
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- New User U Staff on Apr 19, 2023
BEST ANSWER: These may not blend well with the Motion 12's due to the folded motion tweeter.
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- New User U Staff on Apr 19, 2023
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I have Martin Logan’s Motion 12’s (towers) for my left and right. But now I’m looking into purchasing in walls to replace my motion 12’s and wondering if the THX 465IW would be a good replacement for my left and right surround sound?
New User U
on Apr 19, 2023
BEST ANSWER: These may not blend well with the Motion 12's due to the folded motion tweeter.
- Reply
- Inaccurate
- New User U Staff on Apr 19, 2023
BEST ANSWER: These may not blend well with the Motion 12's due to the folded motion tweeter.
- Reply
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- New User U Staff on Apr 19, 2023
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Recommended cabinet volume for a back-box?
New User U
on Jan 7, 2022
How many watts (RMS) will these speakers handle?
A shopper
on Feb 8, 2022
How much space is required between the front of this speaker and an acoustically transparent screen?
Michael H
on May 14, 2022
Which in-ceiling speakers should be paired with these? Will a Monolith line of in-ceiling speakers be announced soon?
Jaxan P
on May 29, 2022
can i put this speaker horizontally as my center channel (under TV)??
A shopper
on May 29, 2022
Can i use this speaker as a center channel under a TV (horizontally positioned)?
New User U
on May 29, 2022
Can this speaker be mounted horizontally and have space for 16 or 24 inch spaced studs to fit between the woofers? It would be helpful of that was listed in the description or specs somewhere. Thanks!
Timothy R
on Jul 11, 2022
Can this be placed horizontally under the TV as a Center speaker, and additionally vertically on either side as L and R?
Julian W
on Dec 22, 2022
What is the -6db coverage angle (horizontal and vertical) for this speaker? at 10kHz and 20kHz if available, or just one value if that's all you have. Thanks!
Jason D
on Jan 25, 2023
Can this speaker be used horizontally as the center channel and vertically as the L and R channels?
Dominic C
on Apr 2, 2023
Reviews
5.0 / 5.0
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Rated 5 out of 5
Was Skeptical / Now I am a huge fan of Monolith
This speaker is a monster. requires some juice for optimal performance. Huge upgrade from my klipsch Center channel.
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Rated 5 out of 5
Happy
Happy so far! I went with 3x 465 for the LCR, 4x 365 for side and rear surrounds and 4 of the monoprice calibers for height, and 2x 10? subs of a different mfg. Monolith 7x powering the main speakers and Anthem MRX740 8k powering the heights. Very clear. I used 5/8? SoundBreak XP drywall and Rockwool safe n? sound in wall insulation. Very happy with end product.




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