Monolith by Monoprice M3100X 3x90 Watts Per Channel Multi-Channel Home Theater Power Amplifier with RCA & XLR Inputs
Product # 43864
UPC # 889028182628
$349.99
In Stock
Save for Later
*Affirm is not available for business or international orders
Qty: 1
$349.99
Qty: 2-9
$339.49
Qty: 10-19
$328.99
Qty: 20-49
$314.99
Qty: 50+
$297.49
Customers Also Shopped For
Questions and Answers
Do not include HTML, links, references to other stores, pricing or contact info.
My question is about:
If your question is about more than one item, click + to add them.
Browse 32 questions
Browse 32 questions
and 35 answers
In addition to my (Answered) question about the XLR inputs, I got an answer saying it's for convenience, I Think this is besides the point of my question. I asked what is the point of having XLR Unbalanced inputs in terms of the Balanced or Unbalanced ability / spec, many other known Amplifiers with XLR inputs are 'BALANCED' for a reason, to have a BALANCED connection and use XLR not just for convenience but to get the signal in Balanced 'form' --- Please elaborate why you chose to use an Unbalanced XLR connection on these lesser / more budget amplifiers, and not Balanced(I think a lot of these buyers of these new amps think they're getting balanced inputs)..?
K G
on Aug 27, 2023
Monolith by Monoprice M3100X 3x90 Watts Per Channel Multi-Channel Home Theater Power Amplifier with RCA & XLR Inputs
Monolith by Monoprice M2100X 2x90 Watts Per Channel Stereo Home Theater Power Amplifier with RCA & XLR Inputs
Monolith by Monoprice M5100X 5x90 Watts Per Channel Multi-Channel Home Theater Power Amplifier with RCA & XLR Inputs
BEST ANSWER: Convenience. Many amps are out there with XLR inputs that are not balanced inputs. Why would you expect balanced inputs on these "lesser / more budget amplifiers"?
- Reply(2)
- Inaccurate
- New User U Staff on Aug 28, 2023
So the XLR is convenience of having an XLR connection without Balanced ability, I understand. - if you check the 'why I Bought this item' section, some are mistaken thinking it's a Balanced connection because it's XLR. This isn't my mistake I read the page / info about unbalanced XLR. I guess it is a mistake to think if an AMP has RCA + XLR, to think XLR is automatically going to be Balanced. why not just have RCA then I'd say. Thanks for responding.
No need to be snarky - especially when you are the seller. Bush league answer, imho. Not necessary.
BEST ANSWER: Convenience. Many amps are out there with XLR inputs that are not balanced inputs. Why would you expect balanced inputs on these "lesser / more budget amplifiers"?
- Reply(2)
- Inaccurate
- New User U Staff on Aug 28, 2023
So the XLR is convenience of having an XLR connection without Balanced ability, I understand. - if you check the 'why I Bought this item' section, some are mistaken thinking it's a Balanced connection because it's XLR. This isn't my mistake I read the page / info about unbalanced XLR. I guess it is a mistake to think if an AMP has RCA + XLR, to think XLR is automatically going to be Balanced. why not just have RCA then I'd say. Thanks for responding.
No need to be snarky - especially when you are the seller. Bush league answer, imho. Not necessary.
This is a strange feature and could be deceiving to the novice user. If you plug a balanced male XLR plug into this female XLR jack on the amplifier, it will certainly pass the signal, but there will be a 6 dB loss. The loss is because only half of the balanced signal is used. The other half goes to ground. I think the description should be modified so as to give a full explanation of what's going on. As I said, this is not how an XLR input is usually wired -- convenance or not.
- Reply
- Inaccurate
- Stephen D on Mar 15, 2024
You're asking non-product developers product development questions. Know your audience buddy...
- Reply(1)
- Inaccurate
- New User U on Aug 31, 2023
Vote for the best answer above!
specifications for MX3100X 3 channe 90 W/ch amplifier????
A shopper
on Jul 21, 2023
BEST ANSWER: Hello and thank you for your question. You can find the specs for this amplifier under the Full Specs tab on the product page.
- Reply
- Inaccurate
- Carlos R Staff on Jul 31, 2023
BEST ANSWER: Hello and thank you for your question. You can find the specs for this amplifier under the Full Specs tab on the product page.
- Reply
- Inaccurate
- Carlos R Staff on Jul 31, 2023
Vote for the best answer above!
Where do you find manuals / specifications for products? I'm interested in the 3 and 5 channel monolith amps, but can't find the detailed specs and dimensions.
A shopper
on Jul 23, 2023
BEST ANSWER: Hello and thank you for your question. The product pages for the 2, 3 and 5 channel amplifiers include a full specs tab and a quick installation guide.
- Reply
- Inaccurate
- Carlos R Staff on Jul 31, 2023
BEST ANSWER: Hello and thank you for your question. The product pages for the 2, 3 and 5 channel amplifiers include a full specs tab and a quick installation guide.
- Reply
- Inaccurate
- Carlos R Staff on Jul 31, 2023
Vote for the best answer above!
when will complete specifications be available for this?
A shopper
on Jul 24, 2023
Monolith by Monoprice M3100X 3x90 Watts Per Channel Multi-Channel Home Theater Power Amplifier with RCA & XLR Inputs
Monolith by Monoprice M5100X 5x90 Watts Per Channel Multi-Channel Home Theater Power Amplifier with RCA & XLR Inputs
Monolith by Monoprice M7100X 7x90 Watts Per Channel Multi-Channel Home Theater Power Amplifier with RCA & XLR Inputs
BEST ANSWER: Hello and thank you for your question. Specifications are now available on the Full Specs tab on each of the amplifier product pages.
- Reply
- Inaccurate
- Carlos R Staff on Jul 31, 2023
BEST ANSWER: Hello and thank you for your question. Specifications are now available on the Full Specs tab on each of the amplifier product pages.
- Reply
- Inaccurate
- Carlos R Staff on Jul 31, 2023
Vote for the best answer above!
What is the wattage if only using two channels?
A shopper
on Jul 28, 2023
BEST ANSWER: Hello and thank you for your question. The channels are independent of each other, so it would still be 90 watts per channel.
- Reply
- Inaccurate
- Carlos R Staff on Jul 31, 2023
BEST ANSWER: Hello and thank you for your question. The channels are independent of each other, so it would still be 90 watts per channel.
- Reply
- Inaccurate
- Carlos R Staff on Jul 31, 2023
Vote for the best answer above!
Vote for the best answer above!
Does this amp (M3100x) come with a trigger cable or do I need to purchase that separately?
A shopper
on Jan 8, 2024
BEST ANSWER: Had to buy it separately
- Reply
- Inaccurate
- Steven S on Jan 17, 2024
- Purchased on Dec 6, 2023
BEST ANSWER: Had to buy it separately
- Reply
- Inaccurate
- Steven S on Jan 17, 2024
- Purchased on Dec 6, 2023
Vote for the best answer above!
does it have subwoofer out?
A shopper
on Jan 25, 2024
BEST ANSWER: No, this is an amplifier not a pre/pro.
- Reply
- Inaccurate
- New User U Staff on Jan 25, 2024
BEST ANSWER: No, this is an amplifier not a pre/pro.
- Reply
- Inaccurate
- New User U Staff on Jan 25, 2024
Vote for the best answer above!
would this be compatible with a denon 3300, thx-460T and thx-365C?
if so im unsure how i would hook the amp to the denon
if so im unsure how i would hook the amp to the denon
A shopper
on Feb 13, 2024
Monolith by Monoprice M3100X 3x90 Watts Per Channel Multi-Channel Home Theater Power Amplifier with RCA & XLR Inputs
Monolith by Monoprice THX-460T THX Certified Ultra Tower Speaker (Each)
Monolith by Monoprice THX-365C THX Certified Ultra Center Channel Speaker (Each) (clearance)
Vote for the best answer above!
Will this amp work okay with small 4ohm Magnepan left, right & center AV speakers?
A shopper
on Jun 20, 2025
BEST ANSWER: Hi, thank you for your inquiry. This will work for moderate volumes in small or medium rooms if impedance stays at 4ohms. I hope this helps.
- Reply
- Inaccurate
- Jhomar R Staff on Jun 24, 2025
BEST ANSWER: Hi, thank you for your inquiry. This will work for moderate volumes in small or medium rooms if impedance stays at 4ohms. I hope this helps.
- Reply
- Inaccurate
- Jhomar R Staff on Jun 24, 2025
Vote for the best answer above!
Can I run mixed load of two 4ohm surrounds and an 8ohm center?
A shopper
on Jun 28, 2025
BEST ANSWER: Hi, thank you for your inquiry. Yes, you can and it will work safely. The amp is well built for mixed loads, and the impedance difference should not cause any issues. Just make sure you have proper ventilation and avoid extreme volume levels for long durations.
- Reply
- Inaccurate
- Jhomar R Staff on Jun 29, 2025
BEST ANSWER: Hi, thank you for your inquiry. Yes, you can and it will work safely. The amp is well built for mixed loads, and the impedance difference should not cause any issues. Just make sure you have proper ventilation and avoid extreme volume levels for long durations.
- Reply
- Inaccurate
- Jhomar R Staff on Jun 29, 2025
Vote for the best answer above!
If I don't have a trigger will amp automatically turn on?
A shopper
on Jul 28, 2025
BEST ANSWER: Hi, thank you for your inquiry. No, this amps requires a trigger cable so it will automatically turn on when it receives an audio signal.
- Reply
- Inaccurate
- Jhomar R Staff on Jul 28, 2025
BEST ANSWER: Hi, thank you for your inquiry. No, this amps requires a trigger cable so it will automatically turn on when it receives an audio signal.
- Reply
- Inaccurate
- Jhomar R Staff on Jul 28, 2025
Vote for the best answer above!
can this be placed on its side?
A shopper
on Oct 11, 2025
BEST ANSWER: Hi, thank you for your inquiry. This amplifier is intended for rack mounting in a horizontal orientation. Installing it on its side is a viable workaround just make sure the unit is well-ventilated. For long-term, optimal performance and safety purposes, it is best to install it in upright position.
- Reply
- Inaccurate
- Jhomar R Staff on Oct 12, 2025
BEST ANSWER: Hi, thank you for your inquiry. This amplifier is intended for rack mounting in a horizontal orientation. Installing it on its side is a viable workaround just make sure the unit is well-ventilated. For long-term, optimal performance and safety purposes, it is best to install it in upright position.
- Reply
- Inaccurate
- Jhomar R Staff on Oct 12, 2025
Vote for the best answer above!
can you place the amplifier on its side?
A shopper
on Oct 12, 2025
BEST ANSWER: Hi, thank you for your inquiry. This amplifier is intended for rack mounting in a horizontal orientation. Installing it on its side is a viable workaround just make sure the unit is well-ventilated. For long-term, optimal performance and safety purposes, it is best to install it in upright position.
- Reply
- Inaccurate
- Jhomar R Staff on Oct 12, 2025
BEST ANSWER: Hi, thank you for your inquiry. This amplifier is intended for rack mounting in a horizontal orientation. Installing it on its side is a viable workaround just make sure the unit is well-ventilated. For long-term, optimal performance and safety purposes, it is best to install it in upright position.
- Reply
- Inaccurate
- Jhomar R Staff on Oct 12, 2025
Vote for the best answer above!
Is there any way I can find out how loud the fan is on the M3100X three channel amplifier? It would be in a small media room and all other equipment does not use a fan or make noise.
A shopper
on Dec 16, 2025
BEST ANSWER: Hi, thank you for your inquiry. For Monolith Amplifiers, it is unlikely to have a loud fan. Its temperature-controlled, variable-speed design means it will be quiet most of the time in a typical home theater setup. For a small media room, it should be perfectly acceptable, though there is a possibility you'll notice it during rare, heavy-load conditions coupled with very quiet movie scenes. If you require additional details, please feel free to contact us at [email protected]
- Reply
- Inaccurate
- Jhomar R Staff on Dec 16, 2025
BEST ANSWER: Hi, thank you for your inquiry. For Monolith Amplifiers, it is unlikely to have a loud fan. Its temperature-controlled, variable-speed design means it will be quiet most of the time in a typical home theater setup. For a small media room, it should be perfectly acceptable, though there is a possibility you'll notice it during rare, heavy-load conditions coupled with very quiet movie scenes. If you require additional details, please feel free to contact us at [email protected]
- Reply
- Inaccurate
- Jhomar R Staff on Dec 16, 2025
Vote for the best answer above!
Hi I'm new so here's my question? How do you add a subwoofer to this amplifier?
A shopper
on Jan 3, 2026
BEST ANSWER: Hi, thank you for your inquiry. You cannot directly connect a subwoofer to this amplifier because it doesn’t include a dedicated subwoofer output or preamp outputs. It simply amplifies speaker-level signals that are fed into its RCA or XLR inputs and then drives passive speakers. It doesn’t have a line-level subwoofer output or preamp outs that an active subwoofer expects. I hope this helps.
- Reply
- Inaccurate
- Jhomar R Staff on Jan 5, 2026
BEST ANSWER: Hi, thank you for your inquiry. You cannot directly connect a subwoofer to this amplifier because it doesn’t include a dedicated subwoofer output or preamp outputs. It simply amplifies speaker-level signals that are fed into its RCA or XLR inputs and then drives passive speakers. It doesn’t have a line-level subwoofer output or preamp outs that an active subwoofer expects. I hope this helps.
- Reply
- Inaccurate
- Jhomar R Staff on Jan 5, 2026
Vote for the best answer above!
I have 2 RCA RCA from my preamp output , but there is only RCA on this amp input. Ay segustion for the cable?
A shopper
on Jan 25, 2026
BEST ANSWER: Hi, the amp expects one RCA per speaker channel, which is normal for power amps. A normal RCA male-to-male cable from your preamp to the Monolith amp should work but you can also use an RCA Y cable.
- Reply
- Inaccurate
- Jhomar R Staff on Jan 25, 2026
BEST ANSWER: Hi, the amp expects one RCA per speaker channel, which is normal for power amps. A normal RCA male-to-male cable from your preamp to the Monolith amp should work but you can also use an RCA Y cable.
- Reply
- Inaccurate
- Jhomar R Staff on Jan 25, 2026
Vote for the best answer above!
Questions For Similar Products
Reviews
5.0 / 5.0
7 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
7
0
0
0
0
Rated 5 out of 5
Nice amp, good price
So far this amp is performing flawlessly. No issues with power and the unit itself looks nice in my equipment shelving.
- Was this review helpful? Yes (0) No (0)
- Flag as Inappropriate
- Was this review helpful? Yes (0) No (0)
- Flag as Inappropriate
Rated 5 out of 5
- Was this review helpful? Yes (0) No (0)
- Flag as Inappropriate
Rated 5 out of 5
Monolith 3 channel
Excellent 3 channel amp which are somewhat rare. I use for center and surrounds in home theatre. Main 2 channel amp used for L and R, so it is perfect for my use
- Was this review helpful? Yes (4) No (0)
- Flag as Inappropriate
- Was this review helpful? Yes (4) No (0)
- Flag as Inappropriate
Rated 5 out of 5
An amazing bargain
I bought this amp to temporarily drive 3 surround speakers in my high-end home theater while the regular $3,000 amp is being serviced. This Monoprice amplifier seems to work just as well and I think I'll keep it in service and pack my expensive amp away for a spare. Excellent value, and I am not disappointed.
- Was this review helpful? Yes (7) No (0)
- Flag as Inappropriate
- Was this review helpful? Yes (7) No (0)
- Flag as Inappropriate
Rated 5 out of 5
Solid 3 Channel Amp
Great amp, works flawlessly. Have it paired with a Denon AVR X3800H, powering Front L,R and Center. Allows for 7.1.4 setup. Easy startup with trigger switch. Clean solid audio. Great value. Highly recommend.
AV setup
- Was this review helpful? Yes (9) No (0)
- Flag as Inappropriate
- Was this review helpful? Yes (9) No (0)
- Flag as Inappropriate
Rated 5 out of 5
- Was this review helpful? Yes (2) No (1)
- Flag as Inappropriate
Rated 5 out of 5
3 Channels of sonic bliss.
This amp has a wonderful warmth and depth of field for an absolute bargain budget price! I am so glad I relied upon the integrity of Monoprice within the marketplace to fill this need.
Old School powered by New, Thanks to YOU!
- Was this review helpful? Yes (12) No (0)
- Flag as Inappropriate
- Was this review helpful? Yes (12) No (0)
- Flag as Inappropriate
Reviews for Similar Products