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    Monolith M300 In Ear Planar Magnetic Earphones
    Product # 24461
    In Stock This item should ship today (2/19/2018) if ordered within 8 hours 13 minutes

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    Monolith M300 In Ear Planar Magnetic Earphones

    In Ear Planar Headphones

    The Monolith M300 in ear planar headphones are the perfect way to experience your music collection. Featuring a 28mm planar driver, these earphones produce a detailed aural landscape and will resolve all the sonic detail from the best recordings. Spectacular imaging, low distortion, and perfectly balanced sound make the Monolith M300 a true audiophile listening experience.

    Planar Driver and Functions

    Planar Drivers
    Open Back Design
    Planar Drivers
    Open Back Design

    Planar Drivers: Not your typical in ear driver! A planar magnetic driver is a flat membrane that is surrounded by magnets. When current is delivered, the membrane produces sound that has lower distortion, better bass, and pinpoint imaging that is usually not found in your typical headphone driver. The size of the driver in the Monolith M300 is 28mm, with bass that extends down below 20Hz.

    Open Back Design: A rarity in an IEM, the Monolith M300 features an open back design. Instead of an "inside your head" isolated experience that traditional earbuds provide, the M300 provides a holographic listening experience. It's as if you're in the middle of a live performance, instead of being closed off from the world.

    Comfortability: The Monolith M300 has been engineered to be comfortable for extended listening sessions. Incredibly lightweight, the M300 comes with multiple sized ear tips, ear hooks and earlocks for long listening comfortability.

    In Ear Planar Headphones

    What's in the box?

    In Ear Planar Headphones
    • 3 Pair Eartips
    • 1 Pair Earhook Black
    • 1 Pair Earhook Clear
    • 2 Pair Earlock Black
    • 1 Cable Connector
    • 1 Carrying Case

    5 Year Warranty

    Buy with Confidence

    Monoprice not only stands behind every product we sell with a 5 year replacement warranty, we offer a 30-day money back guarantee as well! If the product you purchase does not satisfy your needs, send it back for a full refund.

    Quality at a Fair Price

    Quality at a Fair Price

    Monoprice's rugged design and rigid quality control standards deliver high quality products at fair prices.

    Hassle Free Packaging

    Hassle Free Packaging

    Monoprice exists to bring simplicity, fairness, and confidence to technology choices. This product features recyclable packaging that is simple to open, cost effective, with minimal waste, and fully protective as it travels to you.

    Service & Support

    Service & Support

    You're never on your own with Monoprice products! We have a full team of friendly and knowledgeable technicians available to answer your questions, both before and after the sale. Contact our technical support team for questions about our products, troubleshooting, or even suggestions for products to fit your particular needs. Not to be outdone, our friendly and helpful customer service team is here to make your ordering, delivery, and any possible returns a quick and painless operation, from start to finish!

    Model 24461
    Style In-Ear, Universal Fit
    Transducer Type Planar Magnetic, Semi-Open
    Magnetic Structure Toroidal
    Magnet Type High-grade N50 Neodymium
    Diaphragm Type Uniforce double side voice coil design
    Transducer Size 28mm
    Maximum Power Handling 3 watts
    Maximum SPL >120dB
    Frequency Response 18Hz ~ 50kHz
    Total Harmonic Distortion Less than 0.1% at 100dB
    Impedance 22 ohms
    Dimensions 1.3" x 1.6" (32 x 40 mm)
    Weight (per side) 0.48 oz. (13.5g)

    Start typing your question and we'll check if it was already asked and answered. Learn More
    Browse 13 questions Browse 13 questions and 25 answers
    Please, make it available on amazon as soon as possible? I know most of us will buy a pair of them in no time. (at least i know i will!)
    A shopper on Sep 7, 2017
    BEST ANSWER: They are available for purchase on Amazon.
    Do these have MMCX connectors?
    William W on Sep 2, 2017
    BEST ANSWER: Yes, it uses MMCX connectors.
    One of the YouTuber that reviewed m300 said that the carrying case is a little bit small to for the m300 to fit into. Have you guys look into it? I travel quite a bit so it would be a bummer if I couldn't store it in the carrying case. Thx
    A shopper on Sep 23, 2017
    BEST ANSWER: I got my pair yesterday and they seem to fit just fine in the carrying case with the accessories included.
    Where can you obtain replacement ear clips/Ear Hooks for the Monolith M300? What size is the opening of the Clip/Ear Hooks (in Milimeters) of the Monolith M300?
    New User U on Oct 19, 2017
    BEST ANSWER: If you contact customer service, they can send out replacement earhooks if yours have an issue.
    What size of Comply tips fit these?
    A shopper on Oct 4, 2017
    BEST ANSWER: You need the Comply 600's. Same ones that fit the iSine models. They sell as a multipack in most places and are a massive upgrade from the foam tips included in the box.
    Amazon???? When????
    A shopper on Sep 27, 2017
    Still waiting for amazon, because this site does NOT accept international credit card?
    A shopper on Sep 26, 2017
    BEST ANSWER: Amazon (USA) currently shows them at ~$160.
    Shell is made of metal or plastic?
    A shopper on Jan 19, 2018
    BEST ANSWER: Plastic, see "Z Review - Monoprice M300 [Half Price IEH's that work pretty much]" for full review
    the audeze isine 10 has a special cable for an iphone. is there an equivalent cable for Monolith M300 In Ear Planar Earphones ?
    A shopper on Oct 23, 2017
    BEST ANSWER: No, but you could get the cable from Audeze and try it with the M300. In my opinion they sound great the way they are and I am not using any equilization. YMMV.
    Can these be converted to Bluetooth?
    A shopper on Nov 11, 2017
    BEST ANSWER: you can but you'll need to purchase an aftermarket mmcx cable with Bluetooth capability
    any plans to produce a closed back version? closed back is better suited for listening in public/noisy places and avoids disturbing others.
    William O on Oct 2, 2017
    BEST ANSWER: As of right now, we are not working on a closed back version. However, I think you would be surprised at how little these leak sound.
    How do you know you are plugging the correct cord end into the correct earbud, left-right stereo-wise? Are they interchangeable?
    Miguel F on Oct 3, 2017
    BEST ANSWER: Both the cable and earbud have L/R markings.
    Hi, where did my review go? I just posted it about 10 minutes ago and now it is gone???????
    Jim L on Feb 13, 2018
    4.6 / 5.0
    14 Reviews
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1 Stars
    A steal at $150
    Just got mine today, so I haven't had chance to burn them in. I don't know if that is required with these, but they were most definitely for the m1060. I have owned the $349 iSine 10's that these are competing with.

    I've got these plugged into a Dragonfly Red to a PC playing Spotify Premium. Genres are EDM, metal, and 90s rap.

    I ended up sending the Audeze iSine 10's back because I felt they blew it on the treble. The m300's do not have this problem so far. I've only got about about 4 hours of listening so far, so I won't go into detail on the sound, but so far I like these slightly more than the iSine 10s, not even considering the price.

    The iSines feel a little more durable and crisper mids & lows (that could change after these burn in). None of the iSine 10's advantages justify the extra $200 price tag in any way.

    The earhooks are the same size, just clear vs black. They are ~ok in regards to comfort. I will most likely seek out some of the aftermarket earhook solutions meant for the iSines.

    Included tips were two pairs of small (one was silicone, other was foam), and silicone mediums, silicone larges. The silicone are average but the foam feel sub-par and likely to need replacing quickly. Like most other earphones, getting Comply or similar premium tips are well worth the $10-15.

    The removable connectors seem fine; none of the issues they've experienced with their m1060 first run.

    The only other advantage I can give to the Audeze iSine is the ability to get the cipher cable (dac/amp) that works with iOS devices. That model is $400.

    Overall, I think these are an absolute steal at $150. Add another $20-30 of upgrades for earhooks and tips, and I think the m300 stomps all over the iSine10.
    September 29, 2017
    4 months ago
    Best IEM I heard so far, cheaper IEM Planar!
    Monoprice people is a very busy bunch. The Monolith top end headphone product family is growing fast. Soon after the M565, cheaper Planar with the best sounding capabilities possible, the M300 launched. Some nows about Audeze released the first Planar IEM, then the most expensive and most advance. But hey, they cost an arm and a leg. The M300 from monoprice is the cheaper Planar IEM of all out there. Like all Monolith products, the M300 aims at cost effectiveness with no sacrifies in the audio quality. I did not auditionned the Audeze IEMs but I could give a try at few dynamic IEM some costing much more than the M300. Overall the M300 is the best IEM I heard so far. Confortwise it is a bit challenging to find the correct combination of accessories that will matche your hears. The M300 is delivered with enough hear plugs and hear fits. I had to try few combinations before finding the one that fitted me best. About that I would have liked a manual to guide me in the process.
    Soundwise the M300 is stunning, it is hard to believe that these cost only $149.99. These headphone exibit all the goodness of Planar technology over balance, details and smoothness. Bass is tight and nicely extended which is a true advantage with IEMs. All sound at the right place with no excess. Sound stage is wide enough and show decent openess like would a big size Planar.
    The M300 looks nice, but like all other Monolith headphone one would think it could be even nicer but not at this price tag. I cannot say how the M300 sound compared to other Planar IEMs. Among the life size Planars I know, the M300 performers really well despite its mini size. Among IEM I know, the M300 is at the top, even compared to costy units.
    The M300 is a great IEM, might not be suitable for sport.
    I ran the M300 with A LH labs Geek Out 2A SE only with 100mW gain and volume control at 30% not more. this means the M300 can run with most DAPs and maybe most smart phones. It is easy to drive.
    Cost effective but not cheap.
    Great sound.
    Adapted to fit almost all hears.
    Easy to drive.
    Planar technology.
    The M300 is another Monolith that could most much more if it was not from Monoprice.
    It is designed to truly listen to music!
    October 8, 2017
    4 months ago
    Amazing quality sound and value! My new favorite headphones that I can't put down, I highly recommend these!
    Only a couple cons I've got for these so I'll start with those first - note the 5-star review still. The problems aren't significant enough to warrant more than a 0.5 star reduction. What I didn't like: the ear clips are crap as the black pair broke, the cable and 3.5mm jack are a little too bulky, and the sound might be slightly recessed on the treble side.

    I think all of those can be easily fixed though. The sound and soundstage are pretty amazing, so I can definitely get over the problems. Being able to tell where different instruments or vocalists are during the recording is really cool. Using a DAC/amp with them so I can crank it some more with no distortion, and playing around a bit with the EQ settings are probably the only sound enhancements I could want for these. You just have to try a pair of planar magnetic headphones to be able to understand the difference, and these are a much cheaper alternative to any others. If there were more comfortable and durable ear clips, a built-in DAC/amp into the cable with a USB type C plug, or shorter cables that connect to a Bluetooth 5.0 transmitter for more portability (dreaming), these would be pretty close to perfection. I showed these off to my co-workers and they were all ready to buy a set for themselves.
    October 22, 2017
    4 months ago
    OK but not spectacular
    Sound is OK, but benefits from EQ as suggested in other forums. Not as engaging as M1060.

    Comfort is so-so. These are bulky IEMs with straight nozzles and a finnicky attachment system.

    Ear hook quality is poor. One of the black ones already broke despite extreme care in manipulation. Compatible "Groovy" kit from another manufacturer is now exorbitantly priced.

    Hopefully Monoprice will upgrade & replace the ear hooks for early adopter/beta testers. Seems like something that might be 3D printable as well.
    October 22, 2017
    4 months ago
    Planar tech for $150
    Breathtaking instrumental separation, phrasing and microdynamics from affordable little 'phones.

    Some might balk at the concept: but these will requires hours and hours of running in from the amp, before the treble and upper midrange make their slow entrance.

    They are hungry too: I gave mine 1W. The MMCX connectors will also allow amping in balanced mode, likely a further improvement.

    October 4, 2017
    4 months ago
    Sounds amazing for $150
    Finally, some affordable planar IEMs and while it took some time and effort to get them to sound great, I'm glad I purchased these.

    Upon receiving them, they were somewhat unlistenable due to the fact that they became extremely fatiguing only after a few songs, I noticed massive peaks around 500hz and 1.6khz-2.2khz right off the bat, spatial imaging was non-existent and quite frankly, not the sound signature planars are known for. I don't have any experience with planars earphones/headphones, but I do have a ton of experience with planars speakers in home audio setups. I have owned magnepans in the past and built line arrays utilizing BG planars so I wouldn't consider myself a noob when it comes to planars. With that being said, the only positive thing I noticed then was the detail so I decided to break them in and see what happens as well as ordering some talent audio occ silver plated wires.

    I threw on some pink noise in 24 hour intervals for a total of 4 sessions. It's amazing how much they've loosened up after the break in, the massive peaks disappeared I found myself liking them more and more as I listened them longer.

    They still had a couple of things to be ironed out totally so I began to play with my eq settings on my iPhone 7 plus and my god did they respond well to the preset settings. I found myself absolutely loving these when the iPhone eq preset is set to "Latin" and paired with the talent audio silver plated cable. Now it's finally sounding like what a planar should be. The EQ setting opened up the spatial imaging and transparency as well as improving the tonality throughout 50hz-20khz.

    If you have an iPhone 7, make sure to use the OEM Apple lightning to 3.5mm DAC dongle. Using an aftermarket dongle will change the sound characteristic as the dongle is a DAC/amp
    October 18, 2017
    4 months ago
    Life like sound
    These are without a doubt the best earbuds/headphones I have ever listened to. I can hear aspects of the music that I have never even heard with other headphones. It sounds about as close to live music as you can get. One thing that really impresses me is the spatial placement of the sound. I have listened to video recordings of the family with these and the placement of their voices in the room makes it feel as if they are really there. My only negative is that the hardware to hang the earbuds on your ear is a little awkward. It took a bit of effort but I have been able to get them configured comfortably and they don't cause ear fatigue.
    October 20, 2017
    4 months ago
    I was so impressed with the M1060s that I bought these too
    Sound-wise they have great potential. The ear clips fit poorly and are flimsy. One broke right away. I am going to 3-D print an improved version of the ear clips. These are worth experimenting with . Sound is great but fit needs major tweak.
    October 25, 2017
    4 months ago
    Another home run for Monoprice
    Unbelievable for $150. Some have commented on comfort, these are great for me, I can wear for hours with no discomfort. Make sure to try the different size tips, when you get the right one you will hear the difference.
    October 22, 2017
    4 months ago
    As enjoyable to listen to as the M1060s, just in a portable form. Bravo.
    October 17, 2017
    4 months ago


    In Stock This item should ship today (2/19/2018) if ordered within 8 hours 13 minutes