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Definitive Technology StudioMonitor 55

Bookshelf speaker

45 Reviews | 7 questions - 23 answers

Item # 735SM55

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Our take on the Definitive Technology StudioMonitor 55

Don't let the StudioMonitor 55's size fool you — this compact bookshelf speaker belts out big bass that adds depth and richness to your movie soundtracks and stereo music. Each rock-solid cabinet features an advanced 6-1/2" mid/bass driver that's pressure-coupled to a top-mounted bass radiator for high-impact sound. Together, they provide more total bass radiating area than a 10" woofer, but with greater control, definition and speed than a single large cone. A 1" pure aluminum dome tweeter serves up crisp, extended highs that blend in beautifully with the mids and lows. The StudioMonitor 55 is the result of more than 20 years of research and development by Definitive in their quest to create speakers with a perfect balance of style, utility, and performance.

SM55 grille off

Get rich sound from a compact bookshelf design

Don't let the StudioMonitor 55's size fool you — this compact bookshelf speaker belts out big bass that adds depth and richness to your movie soundtracks and stereo music. Each rock-solid cabinet features an advanced 6-1/2" mid/bass driver that's pressure-coupled to a top-mounted bass radiator for high-impact sound. Together, they provide more total bass radiating area than a 10" woofer, but with greater control, definition and speed than a single large cone. A 1" pure aluminum dome tweeter serves up crisp, extended highs that blend in beautifully with the mids and lows. The StudioMonitor 55 is the result of more than 20 years of research and development by Definitive in their quest to create speakers with a perfect balance of style, utility, and performance.

BDSS driver

Definitive's second-generation patented BDSS driver

High-tech driver design for impressive performance

The StudioMonitor 55 is chock full of technology that's also found in Definitive's top-of-the-line speaker models. Its 6-1/2" mid/bass driver uses their latest Balanced Dual Surround System (BDSS) driver design, which places a surround on both the outer and inner edge of the speaker cone. This helps the cone remain more stable as it moves, resulting in clearer, more accurate sound — even at high volume levels. The '55's mid/bass driver also gets Definitive's second-generation Linear Response Waveguide™. This mushroom-shaped post in the center of the cone smooths off-axis frequency response for broad, even sound dispersion and a more realistic sonic "image." That means every listener in the room gets to hear balanced, open sound with lifelike vocals and instruments.

sm55 tweeter

A second-generation pure aluminum dome tweeter yields smooth, extended treble.

Crisp, sparkling highs

Definitive also equipped the StudioMonitor 55 with their latest 1" pure aluminum dome tweeter. This advanced driver is first heat-treated to relax the crystal structure of the metal, then coated with a ceramic that helps produce clear, sparkling highs without a trace of edginess. You'll easily hear the subtle high-frequency details in your music, like the sound of wire brushes gently sweeping the snare head, or the bell-like ring of a brass cymbal.

SM55 bass radiator

A top-mounted bass radiator provides outstanding low-frequency response.

It's all in the details

Definitive paid close attention to other important design elements, too — both visible and hidden. At its heart, the StudioMonitor 55 uses a sophisticated crossover network with audiophile-grade components that include over-sized inductor coils and Mylar film capacitors. These give you a smoother, flatter frequency response, more powerful dynamics, and faster transients, for sound with real presence and immediacy. Sturdy, vault-like cabinet construction also plays a big role in this speaker's performance. The '55's well-damped, cross-braced enclosure features a specially contoured front baffle with tapered sides to minimize diffraction and vibrations that can color your sound and reduce accuracy.

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Did you know?
Your new speakers will probably sound better after several weeks of use than they do right out of the box. That's because the material surrounding the woofers will loosen up, allowing the drivers to move more fully. Definitive Technology estimates a break-in period of 24 to 48 hours of playback before the speakers will deliver optimum sound quality. For more information and helpful tips, check out this article from Definitive's website about conditioning your speakers.

Product Highlights:

  • second-generation Balanced Dual Surround System (BDSS) 6-1/2" mid/bass woofer for clear, accurate sound at high volumes
  • Linear Response Waveguide technology smooths off-axis frequency response provides broad, even sound dispersion and more realistic imaging
  • rigid die-cast aluminum driver basket resists vibration and twisting for lower distortion
  • top-mounted bass radiator for outstanding low-frequency response
  • second-generation 1" pure aluminum dome tweeter delivers clear, extended highs
  • crossover network features oversize inductors and premium Mylar capacitors for audiophile-grade sound quality
  • non-resonant braced enclosure ensures clean, uncolored sound
  • wood grain matte black enclosure with high-gloss, anti-diffraction baffle and detachable cloth grille
  • frequency response: 32-30,000 Hz
  • sensitivity: 90 dB
  • impedance: 8 ohms
  • recommended amplifier power: 20-225 watts
  • dual 5-way binding post speaker terminals for bi-wiring and bi-amping options
  • 12-15/16"H x 7-7/8"W x 12-1/2"D
  • warranty: 5 years
  • Our 60-day money-back guarantee

What's in the Box:

  • Black bookshelf loudspeaker
  • Detachable black cloth grille
  • 2 Jumpers (attached to speaker terminals)
  • 4 Self-adhesive rubber feet
  • Owner's Manual
  • Online Product Registration card

Definitive Technology StudioMonitor 55 Reviews

Average Customer Review(s):

(45 Reviews)

Definitive Technology StudioMonitor 55

Mark from Sinking Spring, PA on 4/13/2018

Crutchfield Customer Review (What's this?)

Sound tremendous- Incredible Value!




Terry from Manheim, PA on 4/11/2018

Crutchfield Customer Review (What's this?)

For the size of this speaker, they deliver the music with great definition and punch. The bass is noticeably pleasant, doesn't overpower and the highs delivered are outstanding. Mids are delivered better than most speakers in the same price range.

Pros: Basically ever aspect of these speakers is everything you want considering the price I paid.

Cons: Speakers are slowing disappearing as a retired model.

Definitive Technology StudioMonitor 55

Anonymous from Saratoga Spgs, NY on 4/8/2018

Crutchfield Customer Review (What's this?)

Love them



SM-55 Speakers

Al from Riverview, FL on 3/26/2018

Crutchfield Customer Review (What's this?)

The performance of the SM-55's is impressive. They are everything I was hoping they would be. I read numerous reviews from several publications and they were all very positive and those helped with my selection. Most impressive is the bass performance considering the size of these speakers. I should mention that I am using these speakers as rear channel surrounds. Not main channel speakers. I have DefTech powered towers as the main channel speakers and a SC6000 powered sub fed by the LFE output. The SM-55's output is well balanced and the timbre is excellent. A good match for the existing DefTech in my system. I highly recommend these speakers to anyone wanting well balanced sound with little to no coloration and a healthy and punchy bass capability considering the size of the cabinets.

Pros: A very well balanced speaker with no noticeable coloration and superb bass performance given the cabinet size.

Cons: None that I've been able to discern.

Definitive Technology StudioMonitor 55

Anonymous from Cleveland, OH on 3/4/2018

Crutchfield Customer Review (What's this?)

This speaker is ridiculously AWESOME.

Pros: Anything positive you can think of.

Cons: Not a con, but I have them paired with a sub.

small speaker footprint, big speaker sound

Arnold from Decatur, IL on 2/22/2018

Crutchfield Customer Review (What's this?)

Replaced a set of 18 year old JBL 6-1/2" 2 ways that I loved. I was amazed at the quality of sound from these. They have good solid bass punch but they really shine in the mids and uppers. Vocals are so out in front of the sound stage. Piano/keyboards are so distinct and the sound stage is just wonderful. At loud volumes of rock and roll they dont lose any clarity nor do they have any harshness. Technology has come a long way for small speakers. These are doing double duty as music and home theater. I am using a 10" Velodyne powered sub and a Yamaha 7 channel home theater receiver with these. I listened to them without the sub and they just seem too lacking of deep bass. You can only go so far without bigger drivers and cabinets. Maybe in a small office setup they would be fine alone. With a sub they really shine in our average sized living room.

Pros: small solid bass good power handling open box for discounted price

Cons: none so far


Richard from Madison, WI on 2/1/2018

Crutchfield Customer Review (What's this?)

I bought these speakers to replace an aging (bought in 2002) pair of Def Tech Studio Monitor 350's. Over the years I have owned various Infinity, Polk and Magnaplaner speakers. But, these are by far the best speakers I have ever owned. They are taller, wider and deeper in size. They go higher and lower and sound great doing it. The highs are clear and open. The mids produce full range and dynamics. The bass deep and authoritative without a subwoofer. The deal was great at Crutchfield. They have great customer service.


Cons: None.

excellent clarity

Emmett from Ridgefield, CT on 1/9/2018

Crutchfield Customer Review (What's this?)

I was looking for B zone speakers and spoke to Barry at Crutchfield. We decided on the Def tech SM55 because of their bass without a sub. I'm very happy with the clarity and will probably get another pair to use as my left and right main speakers.



Def Tech SM55 Rock

Jeff from Miami, FL on 12/31/2017

Crutchfield Customer Review (What's this?)

I am running the SM55's as a 2.0 system with a Pioneer Elite VSX LX102 receiver. The sound is excellent at this price point. I was considering a soundbar but for the sale price of both items this sounds better than any soundbar I have heard, plus I can expand the system with a sub and atmos speakers. I am using this set up for a SonyXBR900e 65 inch . I have had 4 Procinema 1000's, center channel and sub for more than 10 years, also with a Pioneer Elite and that system rocks. So far what I have heard from the SM55's they do sound better. I recommend getting a decent AVR with an equalizer via an app to really use the full potential of these speakers. I am pretty picky when it comes to all my electronics and you would be hard pressed to find a better deal when on sale. This is my first purchase with Crutchfield and the service they provide is second to none.

Pros: Build Quality


Excellent stand alone speakers

Mike from Bean Station, TN on 12/20/2017

Crutchfield Customer Review (What's this?)

Excellent stand alone speakers. I got these for my Mother as a Christmas present. Installed them to a Sony HTS and Onyko CD player. Setup was a snap. I ended up laying the SM 55's on their sides for placement in an existing bookshelf. They do sound great as expected. My Mother loves them.

Pros: Solid cabinet. Excellent sound thanks to the solid Aluminum tweeter, and Bass Radiator. Impressive 6.5" woofer.

Cons: None.

Great speakers

CS from Portland, OR on 10/23/2017

Crutchfield Customer Review (What's this?)

I was really surprised by the amount of bass that these speakers can produce. Very clear mids and highs as well. Great purchase.

Pros: Ground sound out of a smaller speaker!!

Cons: Not much.

Definitive Technology StudioMonitor 55

Anonymous from Hendersonville, NC on 10/8/2017

Crutchfield Customer Review (What's this?)

Very nice sounding speaker for a two channel phono setup. It does have a good amount of bass, as many other reviews have mentioned, compared to other bookshelf speakers. They put out plenty of sound to fill a 400sf room and have very nice resolution for playing vinyl. Doesn't blow me away the way some online reviews rave. I have heard very similar sound out of slightly less expensive speakers in the same category.




Kyle from Alabama on 9/25/2017

Crutchfield Customer Review (What's this?)

Got these for stereo setup mainly used for music. Awesome price and service (always) from Crutchfield.

Pros: Clear, well-rounded sound for music.


Definitive Technology StudioMonitor 55

Alex from Las Vegas, NV on 9/5/2017

Crutchfield Customer Review (What's this?)

I heard these live at another big box audio store ad lode the balanced sound. After looking around, I found them on sale at Crutchfield, who by the way, is my go to audio retailer. I loved them so much I purchased a Defininitive Soundcube and center speaker. Fantastic sound!

Pros: Great balanced sound


Great Bookshelf Speaker

Francisco from Columbus, OH on 8/10/2017

Crutchfield Customer Review (What's this?)

I was looking to replace my klipsch R26F tower speakers with some bookshelf speakers. I was very impressed by the clarity and presence these speakers put out; however, they just were not as in your face as the towers are. Don't get me wrong, these are very capable bookshelf speakers and they sound better as you increase the volume but I needed something more. I gave it a 5 star rating because the speakers performed better than expected for a bookshelf just not a good fit for me and the size of my room.

Pros: Great overall clarity, definition and presence. Hard to beat for the price

Cons: None

Definitive Technology StudioMonitor 55

albert from Virgin Islands on 8/6/2017

Crutchfield Customer Review (What's this?)

I always wanted to upgrade my sm45's to the sm55's. When I saw the sm55's on sale at Crutchfield, I jumped on the deal. I'm glad I did. The sm55's are a big improvement to my system. They sound great for both music and movies. I am now a happy man.

Pros: Great sound for both music and movies. On sale, a Great deal.

Cons: None

Clear, detailed and forceful!

Brian from Okemos, MI on 6/5/2017

Crutchfield Customer Review (What's this?)

Run these off my Yamaha A-S801 integrated amplifier. They can handle anything the 100 continuous watt Yamaha amplifier can send them - producing sound that is clear, detailed, forceful, and with ample bass: Imaging is stunning. They can bang out screaming rock like Jethro Tull or capture all the detail in a Seals and Crofts CD like Summer Breeze. Play something instrumental like from YELLOW, "One Second" CD, cut one - "La Habanera" and the sound is overwhelming in detail and force. Has a metal tweeter so be careful not to pick a new CD player that has an over-emphasis on high frequencies to avoid harshness and listening fatigue. These are great!

Pros: Impressive performance - bass, midrange to highs; clear, detailed, yet forceful and with ample bass. Imaging is stunning. Great value.

Cons: Avoid CD players with an over-emphasis on high frequency which can lead to harshness and listening fatigue.

Stop considering and buy'em!

Brad from Wixom, MI on 4/28/2017

Crutchfield Customer Review (What's this?)

Unbelievably good speakers for the price. Very nice bass extension too. I use them as fronts for a 5.1 system in a medium sized family room. Couldn't be happier.



A Perfect Bookshelf

Oliver from Theodore, AL on 4/16/2017

Crutchfield Customer Review (What's this?)

These monitors are sweet! I could see these paired with a Definitive sub for a fine stereo setup. I purchased them to replace the SR-8080HD for surrounds in my 5.3 system. I moved the SR-8080HD's to the rear surround positions and coupled with the CS-8080HD and BP-8080ST's up front, my system sounds better than I dreamed of. These speakers are "Definitely" worth the price and would make a nice 2.1, 5.1 or 7.1 system. They also make fine surround side, rear and height speakers. I would highly recommend them for their honesty and uncolored sound.

Pros: Uncolored sound, and solid build and size.

Cons: None!

Definitive Technology StudioMonitor 55

William from PA on 3/2/2017

Crutchfield Customer Review (What's this?)

I was looking for some new book shelf now I'm very happy

Pros: Very good

Cons: No cons

Definitive Technology StudioMonitor 55

JAMES C from Aberdeen, NJ on 12/26/2016

Crutchfield Customer Review (What's this?)

I have had these SM 55's in a all around 5.1 Def Tech system for a year in the surround position. First with Mythos ones in the main position but now with SM 65's in the main position and all I can say is wow. The way in which the SM 65's and SM 55's work together is something to behold. I highly recommend using Studio monitors all the way around if your using them in a HT setup. The SM 55's really portray every single detail and every single sound beautifully in every movie or song you are listening to. Just so impressive.This line, the Studio monitor line from Def Tech just might be the best kept secret in speakers.

Pros: Accurate, powerful, beautiful sounding speakers, really, really impressive.

Cons: Just like the SM 65's you won't find a con because there isn't one to find.


Miguel from DORADO, PR on 9/11/2016

Crutchfield Customer Review (What's this?)

This Definitive Technology StudioMonitor 55 just sound great. What a buy. Very satisfied.

Pros: Sound, size, price, built quality.

Cons: None so far.

Big sound, small package

Pogre from Mesa, AZ on 7/7/2016

I just got these to replace my B&W DM 570 front speakers and I'm amazed at how big these speakers sound. I already had the Promonitor 1000's for my rear speakers so I wasn't completely caught off guard, but still... wow. These are floor standing speakers masquerading as bookshelf speakers. The mids and highs are bright and crisp without being harsh, and that bass... This little speaker digs deep. I would almost say a sub isn't even necessary, but with my large room and a receiver with 2 subwoofer outputs I opted to pair them with 2 Klipsch RPW 10 powered subs and couldn't be happier, and from what I've been reading, they get even better after the break in period. I consider myself a budget audiophile, and these babies definitely fit the bill for me. They can hold their own with some that are double or even triple the price. I'm definitely a DefTech convert. The CS 8040 is my next purchase. That will complete my 5.2 surround setup.

Pros: Big sound in a little speaker. You don't need a super amp to make them sing. Any solid brand avr (Denon, Onkyo, Yamaha, etc) with decent power output will work beautifully. Great speaker for the money.

Cons: To be nitpciky they look kind of ugly with the top grille removed, but that's really being snobby and easily resolved by leaving it on. I prefer the front grille removed with the top left on.

DEFTEC StudioMonitor 55's

Jim from Brentwood, TN on 6/27/2016

Crutchfield Customer Review (What's this?)

Excellent product! Sounded great right out of the box. Used as surround left and right channels with a Denon AVR-3311CI. Replaced in ceiling speakers and these provide the depth and presence that I was missing for 5.1. Crutchfield service and support always exceeds expectations. Need to get another pair for 7.1!

Pros: Great sound reproduction from movies and music. Great compromise between size and output.

Cons: None.

Love it

Raman from Wichita, KS on 6/20/2016

Crutchfield Customer Review (What's this?)

Wow , I love it and very pleased with it



Definitive Studio Monitor 55

Mr Bill from Canyon Country, CA on 6/5/2016

Crutchfield Customer Review (What's this?)

Added a pair of these def tech studio monitor 55's too my 5ch def tech sys using them as my frt highs, so now my sys is 7ch,very happy with sys.

Pros: Hi end

Cons: None

studio monitor 55 speakers

ignacio from Altamonte Springs, FL on 4/4/2016

Crutchfield Customer Review (What's this?)

i am very pleased with the sound and they are just what i was looking for. i have them placed at both ends of my audio cabinet where they look great and deliver the punch i was looking for.the two grills have not fitted well into the slots provided, like they do not engage fully with the holes, so they are put away in a drawer. i am planning on returning them to you for this reason. i don't know how a company like this could have missed that.



Definitive Technology StudioMonitor 55

Julio Diaz from Delaware on 7/2/2015

Crutchfield Customer Review (What's this?)

Overwhelmed! Utterly . The amazed how detailed these speakers deliver my jazz CD's Looking forward to hearing them all over again. Movies are so much more detailed. The best part was receiving them the next day two days prior to Father's Day. Happy Fathers Day to me.




Doug from New York on 2/14/2015

Crutchfield Customer Review (What's this?)

Running a Yamaha Aventage 1020, with a SVS PB1000 sub, DT PC 1000. Replacing Bose 901s, 301s, and a set of DT450s. Intially disapointed by the 55s. They are a lot lighter then the 450s, probably in the magnets. The 55s do not seem to be as warm and present as the 450s. Set them up using Yamaha mic and YPAO. The 55s did not reproduce the bass and prsence of the 450s even then. The 55s have the bass radiator on the top the 450s on the side. So I laid the 55s on their side with the raditor facing in, and yes much closer to the 450s. Give them som break in time and yes the bass is coming alive, the highs and mid range are tremendous. Still waiting for the bass. They are very sensitive to the source of your listening if it is or is not in the source music you will either hear it it or not. I run them through pure dierct mode on the Yamaha which is just 2.0 with no processing whatsoever. Starting to come alive. Well still not there yet. So I bi amp them to the Yahmaha using the extra amps per Yamahas instruction, and 14 gauge monoprice wire. Run the YPAO again 55s still on their side. The clarity and separationn of instruments is tremendous. Do not bi amp looking for more volume do it for sound clarity. The biamped 55s remind me of my Dads Acoustic Reserch speakers from the 60s ran with a Lafeyette receiver. The biamping sets them alive, I hear things I have never heard before. Added DT ProM 1000s as surrounds and the Timbre match is incredible, movies blow me away.

Pros: Looks, Solid build, BiAmping is a go to, perfect timbre match with DT Pro Monitor 1000 series surronds and center, movies are incrediable with this set up. They blend very well to perfectly with the SVS turned down and the Yamaha crossover set to 100. Got to give Yamaha some credit to awesome receiver. Def Tech is superb You cannot go wrong with there set ups. I have been a fan of reflected music for some time now starting with my 901s. DT has won me over for a more traditional approach.

Cons: Not sure there are any. Must be patient and willing to tweak there location. Remember trying laying them on their sides with the radiator either facing in or out depending on your room and preferences.

Great Monitor Speaker

Walt B. from California on 12/15/2014

Crutchfield Customer Review (What's this?)

My Def Tech SM 55's are not fully broken in yet but they are already sounding fantastic. I upgraded from the SM45's which are terrific speakers in their own right, but these are a definite step up. They already compete quite well with my other speakers, Monitor Audio Silver RX6 tower speakers, and when they're fully broken in I believe they will best them.

Pros: Just about everything.

Cons: Nothing at this price point.

I Love This Speaker

DaveG from SLC, UT on 11/26/2014

Crutchfield Customer Review (What's this?)

Awesome value and fills up my room with great sound better than I could have imagined! Great buy on a great speaker!

Pros: Fits nicely on a standard bookshelf. Looks great!

Cons: None

Definitive Technology StudioMonitor 55

supermax from Kokomo,Indiana on 10/9/2014

Crutchfield Customer Review (What's this?)

Moniter55 speakers have exlent sound. The highs and lows are produced very well. Very fine speakers.



A Good Speaker

Andy from Colorado Springs, CC on 10/2/2014

Crutchfield Customer Review (What's this?)

This is a decent speaker, but when I compared to my older JBL T100 speakers it was no contest. The older JBs had all the highs etc. of this speaker, but way more 'body'. I carefully AB'd these 55s with the JBLs they just did not make the cut, even with my sub.

Pros: Size evidently still matters leaving these speaker woefully thin.

Cons: Great size and possibly sound for much smaller room.

Definitive Technology StudioMonitor 55

Judge Tom from Olney Maryland on 5/18/2014

Crutchfield Customer Review (What's this?)

This is an outstanding product . I replaced two 30+ year old Infinity 48" high tower speakers each with double 10" push pull woofers with these mini monitors, in a 12 by 20 ft room with openings to a dining area and a hallway, and did not expect too much. I was astounded by these little gems in tandem with a MartinLogan Dynamo 700 sub. Even without the sub the bass was deep and room filling. With the sub they easily surpassed my old infinity monsters. I especially liked the fact that they are not ported and have a passive top radiator so my bass does not shoot out into the dining room and hallway as with a rear ported speaker.. Critical listeners have confirmed my evaluation. Delivery by Crutchfield was within 23 hours of my order.

Pros: Outstanding quality and value for money.

Cons: none

SM 55

Antonio from Guaynabo, PR on 4/5/2014

Crutchfield Customer Review (What's this?)

Rediscovering my very well-recorded and extremely eclectic music collection on my new small(a bit less than 12' x 9') listening room. Paired to a quite nice turntable(on a solid wall mount), a beefy (150w/ch @ 8 ohms) made in Japan receiver and two very good cd players. Nothing "high-end"(marketing bull).just perfect placement (spikes on shelf, tweeters at ear level, seated, slight toe-in). Proper break-in. Attained the ideal of music reproduction: total intelligibility, a big soundstage, extended dynamic range and more than the occasional,watery-eyed goosebumps. These babes are mind boggling. Deep-flat bass, holographic presence of voices and instruments, sweet decay of cymbals and guitars... oh my...if music is a drug, as it is for me, these machines are akin to intravenous delivery devices.

Pros: Premium floor-standing speaker sound for the size and price of merely good bookshelf's. (If that is not for you a breakthrough, my friend, consider sitting down and wait for cold fusion or world peace.)

Cons: Kind of ugly without grilles, but the magic seems unaffected by them, they seem acoustically transparent. Anyway got the SM 55's for function, not form.The black finish on dimmed light makes them to visually disappear, which is good. Anyway I do not go out with them, but with my wife. Now, she not only looks good, but she LOVES our new small room. Was that kinky? You bet ! Remember college dorm? There you go. A good music room is the ultimate time machine.

def tech studio monitor 55

Houn from Bk on 2/19/2014

Crutchfield Customer Review (What's this?)

Great sound, tight looking speakers

Pros: Size, look, and they kick they make love to your ears

Cons: None

Great Sound

Anonymous from S San Fran, CA on 1/23/2014

Crutchfield Customer Review (What's this?)

These speakers are worth the money, great sound for such a small speaker



A bargain

gnakasato from Louisville, KY on 12/8/2013

Crutchfield Customer Review (What's this?)

Outstanding speakers. Great sound reproduction with lots of bass. Very neutral without sounding too bright or too boomy. Absolutely no distortion even after cranking the volume of my amp all the way up (rated at "130W" per channel). I'm using them as free standing speakers on stands, and after using the amplifier microphone to use the Audyssey MultiEQ system to calibrate them, it detected them as "Full Range" speakers. Impressive. I still set the crossover at 60Hz, though, per the manufacturer recommendations, since I have a dedicated subwoofer for the lower frequencies (relieving the main amplifier from having to run those power hungry lower frequencies). Nice craftmanship. For the price, they are extremely hard to beat. Even more so if you get them at open box price.

Pros: Great sound reproduction. For music and movies. Even when used as freestanding speakers.

Cons: Size. A little deep for a standard "bookshelf". But form follows function. And that extra depth allows it to accomodate the top 10" passive radiator that gives it the capabily of full bass reproduction. So for "full range" speakers, they are actually "compact".

Studio Monitor 55

Carlos Danger from New Mexico on 10/19/2013

Crutchfield Customer Review (What's this?)

I tested several bookshelf speakers to be used with a McIntosh Reciever area B stereo rated at 100W/channel. The DR set has a fuller range sound than any of the new Martin Logan and B&W offerings. For a set to be used with no sub the DR is it for me.

Pros: Full sound

Cons: None for a small room stereo application.

studio 55

ronq from phoenix, az on 8/1/2013

Crutchfield Customer Review (What's this?)

These speakers are relatively small in my opinion, but deliver terrific sound. I am using them as front right and left speakers and I am very pleased with them. Crutchfield had them at them at the going price. They delivered them very quickly. They were packaged safely and arrived without damage, and I had the peace of mind of having Crutchfield's guarantee.

Pros: great sound, small package

Cons: none

Super performer, period.

VictorA from San German,PR. on 6/3/2013

Crutchfield Customer Review (What's this?)

This is a great performer, I`m using the SM-55 as my mains. The partner in crime for surrounds the sm-45, and together the SM`s work as one and with authority...not only has the bass response of a much larger speaker, it's a great-sounding speaker. The StudioMonitor 55s didn't seem to mind playing loud enough to rock out in my large loft space.... Great dynamics, imaging and soundstage. 100000 thumbs up

Pros: Well Built, Heavy but still a beauty...

Cons: None

Solid Performance, expected quality

rwwaters from Los Angeles, CA on 4/10/2013

Crutchfield Customer Review (What's this?)

These babies are exactly what I am looking for. I became acquainted with Definitive several years ago at Best Buy of all places... the 55s are great for the user who doesn't have a lot of space, but still wants room-filling, rich, and bright sound. I have these powered off a dinky NuForce Dia running in tandem with an older Definitive pair of ProCinemas for fuller sound space. Also have a Definitive sub powered from the Dia's line out. You could easily run these 55s by themselves, but the sub works for my taste.

Pros: design, build quality, style, suave

Cons: maybe a little large, but not really that large considering the sound you get from them

Good in Price Range, Not Great

Mike W from Knoxville, TN on 12/15/2012

Crutchfield Customer Review (What's this?)

Overall, these are very good speakers in this price range. I planned to use them for music only in a 2-channel system in my bedroom. I was pleased with the midrange and treble tonaility and detail. Bass extension was very good for this size of bookshelf speaker, due to the passive radiator on top, as other reviewers have mentioned. However, I was somewhat disappointed with the imaging and soundstage. Regardless of placement, it would never quite snap into focus. I had the entire short wall of the room to play with, but never found an optimal placement. I have replaced these with a pair of small floorstanding speakers that were very easy to place, and provide excellent imaging and soundstage depth. I'm going to try these as front speakers in my home theater system, a Def Tech Pro Cinema 600. Hopefully they will work well as an upgrade to those speakers.

Pros: Excellent bass extension for bookshelf speaker, very dynamic, good mid and treble detail.

Cons: Bass a little muddy, soundstage and imaging disappointing.

impressive sound

JWS from San Luis Obispo, CA on 10/21/2012

Crutchfield Customer Review (What's this?)

My old speaker towers needed replacing after a room remodel. Working with a Crutchfield adviser helped me get past my concern that the bookshelf speakers would not be an adequate substitute. These speakers are phenomenal. The 6.5 inch woofer provides plenty of bass (I do not have a subwoofer, and don't feel that I need one for classical music), and the aluminum tweeter gives ample high range, although I have to boost the treble on the amp to get a good balance. The design of the speaker produces bass from the top as well as the front, possibly explaining the remarkable force of the bass range. These speakers more than fill a large living room with cathedral ceiling and easily take the power beyond what is a comfortable listening volume. Top-notch performance at a reasonable price.

Pros: compact design; excellent sound; reasonable price

Cons: caution needed when handling to avoid damaging the front and top

Great bookshelf speakers

BillW from Eugene, OR on 3/24/2012

Crutchfield Customer Review (What's this?)

I spent quite some time looking at a variety of bookshelf speakers prior to picking up a pair of these. I wanted a non-ported design that had decent lower end extension and these certainly fit the bill. While probably not suited for bass heavy Rap, electronica or dubstep they work great for the Jazz, Classical, Blues, Metal and Rock I've played through them. While there was some slight harshness initially to the highs but that mellowed after about 15 hours of use. Overall a great bookshelf speaker and I'm pleased with my choice.

Pros: Beautiful cabinets, look great with grills on or off. Accurate with great sound and surprising low end from a bookshelf speaker.

Cons: Not so much a con as a warning, be careful when removing the speaker from packaging. These speakers ship with the grills off, and the top grill covers the bass radiator. Recommendation when removing from packaging is to lift on the sides to avoid possible damage to speakers.


Hands-on research

Product Research

Driver Technology
Enclosure Design
Mounting Options

Driver Technology

StudioMonitor Series: The Definitive Technology StudioMonitor 55 is a compact bookshelf loudspeaker designed for use in audio/video entertainment systems. Because the StudioMonitor 55 is a true full-range speaker with extended low-frequency response, it delivers superb performance both as stand-alone speaker and when combined with a separate subwoofer. Due to its compact size, wide-range, high-power handling, and natural articulate clarity; the StudioMonitor 55 loudspeaker is ideal for use as front, center, or surround speaker in a home theater environment.

2-Way Loudspeaker: Each Definitive Technology StudioMonitor 55 loudspeaker features a 6.5" second generation BDSS cast-aluminum basket midrange driver and a 1" pure aluminum dome tweeter.

  • 2nd Generation BDSS Midrange: The 6.5" cast-aluminum basket midrange driver features Definitive's patented Balanced Double Surround System (BDSS) technology that supports the speaker cone at both the inner and outer edges allowing longer, more linear excursion for greater clarity and finely textured inner detail.
  • Pure Aluminum Dome Tweeter: The 1" tweeter is a pure aluminum dome, which has been heat-treated to relax the crystal structure and then coated with a ceramic to produce smooth, extended highs. A new patent pending Linear Response Waveguide smoothes off-axis frequency response and disperses sound over a wider area for crystal clear intelligibility for every listener in the room.

Pressure Coupled Radiator Design: The 6.5" BDSS midrange driver is pressure coupled to a top-mounted 6"x10" racetrack bass radiator to extend and amplify bass frequencies. The total bass radiating from a StudioMonitor 55 is substantially greater than that of a single 10-inch woofer but with far greater control, definition and speed than a single sluggish large woofer. The StudioMonitor 55 speaker's bass performance offers depth, detail, and musicality.

Note: Due to the top-mounted racetrack bass radiator, there should be at least 2" of space above the bookshelf loudspeaker.

Phase-Coherent Crossover Networks: The crossover network is the real heart of a loudspeaker as it is responsible for perfectly blending together the sound of the various drivers into a musically seamless whole. The sophisticated crossover network design used in the StudioMonitor 55 loudspeaker features premium audiophile-grade components; such as oversized inductors and Mylar capacitors for audiophile-grade sound quality, with linear phase and frequency response. An integrated Zobel network flattens the impedance of the system so that even budget amplifiers will be able to drive the StudioMonitor 55 loudspeaker (although a premium amplifier will bring out all the performance it has to offer). As a result, the audio signal's phase coherence, transient response, and dynamic integrity is preserved for absolutely lifelike music and home theater reproduction in your home.

Enclosure Design

Non-Resonant/Low-Diffraction Cabinet: The Definitive Technology StudioMonitor 55 bookshelf loudspeaker employs a non-resonant MDF braced enclosure that ensures pure, uncolored performance. The specially contoured high-gloss baffle around the drivers and the tapered enclosure sides enhance sound quality by minimizing diffraction distortion.


Bi-amp/Bi-wire Binding Posts: Each StudioMonitor 55 bookshelf loudspeaker has two sets of heavy-duty, all metal binding post speaker terminals (connected by metal jumpers) to attach your receiver's speaker wire. Using the dual binding posts, you can bi-amp or bi-wire the speakers for even better sound. The binding post speaker terminals will accept bare wire (up to 10AWG), pin-connectors, spade-connectors, and banana-plugs (single only).

Color-Coded: The speaker's binding posts are color-coded (red/black) for easy identification between positive and negative.

Mounting Options

Table-Top Mounting: The StudioMonitor 55 loudspeaker can be simply placed on a bookshelf, table-top, or speaker stand (such as the Definitive Technology StudioStand, sold separately ). Four self-adhesive rubber feet are included to protect your furniture's surface.

Wall Mounting: The optional PinPoint heavy duty side-grip wall-mounting bracket (121AM41B, sold separately) can be used to wall mount the speaker.

Note: The speaker does not include any type of wall-mount bracket, threaded inserts, or keyhole slots.

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.

Q & A

Customer Q&A

Crutchfield asked  
Why did you buy this?

high power handling, freq response, small [ LEWIS  Apr 06, 2018 ]
Between Definitive Tech's consistently good products and the Crutchfield price and customer service, these are a win from any angle. [ Terry_L  Mar 15, 2018 ]
experience with Definitive Technology. I needed a bookshelf speaker. [ Ronald  Mar 07, 2018 ]
Moved to smaller living space. Giving up floor standing speakers. Need bookshelf size speaker with either a front port or passive radiator. This speaker seems to have the same drivers as the new Demand 11at a price that I just couldn't pass up. Definitive Technology has an excellent reputation. Excellent reviews of this speaker. I hope I like what I hear. [ Frank  Feb 19, 2018 ]
Def Tech has great speakers and at this price from Crutchfield I couldn't pass this up these speakers. [ rick  Feb 14, 2018 ]
Incredible sound from a relatively small, gorgeous cabinet. Bought my first pair and expected to want a subwoofer, but the bass response on these is excellent, natural and perfect for music. None needed! The sound rivals that of my massive Mirage Omnipolar floorstanding speakers which I had been happy with for a long time. Bravo, Def Tech! [ DAVID  Feb 14, 2018 ]
Recommendation by Sam - customer service rep. [ Jeffrey S.  Jan 08, 2018 ]
ON SALE!!! [ CHARLES J  Dec 27, 2017 ]
Excellent value and quality [ Jeff  Dec 27, 2017 ]
Have def tech speakers now , real happy with those , just upgrading.... [ Jerry  Dec 14, 2017 ]
I was looking for some good speakers for a 2.0 setup in a dorm room, mainly for music and movies. I haven't heard them in person, but for the price and the specs they offer, they seemed like such a good deal. I (am confident I'll) love the broad frequency range on the SM55s due to the passive radiator. I don't want to have to run a sub in this situation, and these sound like they should fit the bill perfectly. I look forward to hearing what they can do! [ Donald  Dec 14, 2017 ]
I own a ton of Definitive Technology speakers and sub woofers. I'm getting these for my Mother. I know I can rock out when I visit. This is my favorite place to shop for for audio and video equipment. Great product information, Customer Service, delivery, and total satisfaction, every time. Thank you to everybody at Crutchfield. [ Michael  Dec 05, 2017 ]
I own the studio monitor 45. Love them. Want the studio monitor 55 for second system. [ MARK  Nov 21, 2017 ]
replacing my old skull Infinity RX3000 I'm hoping these can fill those shoes somewhat. Looking for mainly audio rather than theater and the reviews look promising. Toss up with Martin Logans so we'll see... [ William  Nov 15, 2017 ]
These speakers are compatible with our center channel. Good value [ William  Oct 23, 2017 ]
reviews and pricing, also the size, I am replacing tower speakers that are too big. [ Cory  Oct 09, 2017 ]
Already had the 65's for my front speakers, have these as rears when playing 5 channel stereo now it is ridiculously good. Amazing products [ ANDREW  Aug 19, 2017 ]
To match center channel [ Ronald  Jul 31, 2017 ]
Definitive Technology Speakers I am using for years. Great sound quality for great price. Design by American engineers. [ Christopher  Jul 22, 2017 ]
Superb speakers for a pretty tight space. Replaced (old) large Infinity floor models and sound better in many ways. [ S  Jun 11, 2017 ]
Good product, reviews, support. [ Tim  Apr 19, 2017 ]
Ratings by both customers and audiophile media that match my need for clear articulation of dialog, background and placement of instruments/vocalists. As a bonus, higher efficiency and deep base (thanks Larry for pointing this out). [ Michael  Mar 20, 2017 ]
Sale price and already have a DT sound bar [ duane g.  Mar 13, 2017 ]
I recently purchased one set of DT-Studio 55s for my A/V system. This is the second set for the other end of the room. Next could possibly be a center channel or sub woofer. [ J.  Feb 16, 2017 ]
These speakers seem so much bigger than bookshelf speakers. Crisp highs and warm mids. A surprisingly low db reaching speaker. Would recommend to anyone avoiding the towers. [ Robert  Aug 11, 2016 ]
You used to be able to go into an audio store and actually LISTEN to speakers and make a selection. Today, you have to go by specs and user comments. In the case of the Def Tech 55s, the specs are impressive and user comments, although sparse, were favorable. We'll see when I get them in the house and set up. [ James  Mar 29, 2016 ]
I like the sound of these speakers over others in there price range [ JOHN  Dec 19, 2015 ]
I was searching for bookshelf speakers to fit into a TV storage unit I installed, and these are well regarded speakers that match the sound quality of the speakers I already own. In addition, the discounts running on them helped bring the price down and made the decision easier. [ Eric  Dec 10, 2015 ]
These Monitors offer increased Bass (30 vs44) and Treble ( 30,000 vs 24,000) response to complement by Polk floor standing speakers already in place to widen my marches on.......oh, Joy...and as has been the case for over 25 years, I have complete faith in the Price, Value, and Quality from "The Crutch"! [ Dennis K.  Dec 07, 2015 ]

7 questions already asked

I recommend the Sanus BF16B speaker stands. I prefer stands with two vertical posts as they are more stable and this model also has a wider rectangular base which is also more stable. I have also found that this height is good for the pair of Def Tech Studio 55 speakers that I have had for seven months. [ BRIAN  Nov 11, 2017 ]
Yes you can but beware that the small sub is on the right side so you can only lay it down one way. Should matter. These speakers are great. [ Dominic  Jul 04, 2017 ]
Yes you can. I have done so myself. Logo will be sideways, though. [ Robert  Jul 04, 2017 ]
@LeoD I have these speakers and they are fantastic. Great bass and mids for a bookshelf. As far as hanging them on the wall I dont think this would work well, they are pretty hefty and heavy. Plus, the sub thats built in needs some wall to get the reflection. I have mine on a bookshelf (ironically) and with a Definitive sub and center channel its perfect for a 5.1 system in a normal living room. If you want to hang/mount these I would go with smaller satellite speakers if you have bass covered with a cube already. [ Dominic  Apr 28, 2017 ]
No sir, no problem because these are full bodied speakers and that's exactly where i have mine. Great sound. But uf tou really want to do something special with your home theater, add a definitive tech powered center speaker [ DORAN L  Apr 28, 2017 ]
My SM55 speakers are only 8 inches away from my TV on both sides. I had the same concern when I bought mine. I've no problem at all. I am completely happy with the performance. [ James  Dec 21, 2015 ]
I have these as front speakers in a wood cabinet under my TV and there is zero impact on the picture. [ Andrew  Dec 21, 2015 ]
You shouldn't have interference problems at all unless you have an older CRT model.My StudioMoniters are only 8" from our LCD TV and work great.Im sure you will be very happy with choosing the StudioMoniters,great speakers! [ Dolan  Dec 21, 2015 ]
I have a Def Tech Super cube that sounds great! [ Andrew  Dec 21, 2015 ]
I have an older Polk Audio Subwooferr which works extremely well with this speaker [ JULIO C  Jul 17, 2015 ]
The answer to your question is base on your room size and bassholic level. Go to svsound and use their merlin tool to match a svs sub with the SM55. I used my SM55 as surround speakers so they don't have to work as hard compare to a stereo setup. In conclusion, listen to the SM55 before you buy them to judge if they generate enough bass for you. [ DAVID  Jul 17, 2015 ]
Bi Amping: It only makes sense if you have an amplifier that allows you the ability to separate the output in two sections, one for the tweeter and the other for the woover, otherwise it's just so to speak adding bigger gauge speaker cables. [ New User  Sep 13, 2015 ]
Hello, I do not know. I h e not used bi amping. [ Terry  Mar 11, 2015 ]
Sorry, I have no idea what "bi-amping" is. [ JAMES EDWARD  Mar 09, 2015 ]
It works great bi-amped. Is a great option for this Def Tech. I love it!!! [ VictorAriel  Mar 09, 2015 ]
The speaker does provide extra terminals for this purpose. However I really am not convinced that the extra effort and expense is worth any perceived benefit, which I suspect may be imaginary. Perhaps a more elaborate speaker system might warrant it. I would put the money in a better sub woofer or amplification. That said I find the performance of this speaker to be superb' and not in need of bi- wiring, or bi-amplification. [ Thomas R.  Mar 09, 2015 ]
George, I have not bi-amped the 55's yet, but I plan to, just have to spring for the right receiver/amp. I have read all the literature and the 55's are set up for bi-amping and should benefit from it. Bi-amp the 55's then add the Definitive Tech super cube bass. That sound would be outstanding. [ JOHN  Mar 08, 2015 ]
I would venture to say: Yes, it's a good option. I am driving mine with an Onkyo receiver (which doesn't allow for bi-amping) because it has the ability to receive radio streams via its Vtuner function. But, having owned audiophile speakers (Maggies) and C-J electronics, I can sense that these speakers could deliver much more satisfying sound if only they were provided with better-defined signals. So, if you can bi-amp the speakers, I would advise you to go for it. [ PHILIP S  Mar 08, 2015 ]
I never tried it and they sound great. I use them as my front speakers [ KYLE  Mar 08, 2015 ]
"Definitive ProCenter 2000 (BK) Center Channel Speaker Item #: 735PCTR2KB" This is the speaker I used. I like it. Definitive may have some better speakers, but this is all my pocket book would stand at the moment. I use a Yamaha receiver to run my speakers. [ JAMES EDWARD  May 06, 2014 ]
As you should always match brands on all speakers for a multi-speaker setup, I suggest going to the Definitive Technology website and check out their center channel speakers. Something like the CS-8080HD, CS-8060HD, or CS-8040HD should blend nicely with the SM55 speaker, all which are available at Crutchfield. [ PHILIP  May 05, 2014 ]
I am using the Def Tech CS 8040 HD in my set up. I have SM 65's for the mains and SM 55's for surround. All work in perfect unison. [ ERIC  May 05, 2014 ]
Use the SM-65 in horizontal position. That's what I do and it sounds perfectly matched. [ Grisha Goryache  May 05, 2014 ]