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Infinity SM-155

Studio Monitor Series Loudspeaker System (1996-98)

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Infinity SM-155


Type: 3 way, 4 driver loudspeaker system

Frequency Response: 29Hz to 27kHz

Recommended Amplifier: 10 to 300W

Crossover Frequency: 500, 5500Hz

Impedance: 8Ω

Sensitivity: 102dB

Bass: 1 x 15"

Midrange: 2 x 4.5"

Tweeter: 1 x 1"

Finish: black ash or walnut vinyl

Dimensions: 17.75 x 40.25 x 12.5 inches


Related Catalogues

Home Hi-Fi and Home Theatre

Studio Monitor Series

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Reviewed Feb 24th, 2019 by aatrepair

I am a pro audio servicer professionally for 32 years after getting my electronics B.
S. degree. I've done lots of repairs on this series and have owned and recommended the 150 series to others. They take very little power to shake the walls. Unfortunately all the foam surrounds go bad by 20 years. Sometimes the tweeter diaphragms fail under extreme levels. Recommend bypassing fusing on Xover and bypass mid-range level control. I have gotten diaphragms directly from Infinity at reasonable cost.
These were low cost, but hi high-performance for the money. One of the best values new and now used on Craigslist. Be sure to check the surrounds carefully and replace before damage to voice coil. If you love to crank it up loud with full deep bass and clear and clean mids and Highs then these are highly recommended!
BTW I also have B&W 801 matrix S3 speakers in my studio. The Infinitys are not quite as good but they were 1/20 th the price.

Reviewed Dec 14th, 2018 by CraigSedik

My only complaint is moving these giants, Have owned them for 20+ years and still am amazed at how the sound fills the room. Just connected them to a slightly more robust amp, and still smile on the downbeat.

Reviewed Aug 25th, 2017 by motocross93

I bought a pair of the Infinity SM-155's from uBid back in 1998, were some of the last new ones available at the time, got them for some ridiculously low price, around $400. These retailed for $1200-$1500 I believe. Have never had any problems with them, and they have been used at least 3 times a week for almost 20 years. I very rarely use this feature- but the fact that they each have midrange and high frequency level adjustments is really great, especially if you have an acoustically live or dead listening room.

Had a neighbor come over to complain a few years back, said his entire house was shaking. Have to be VERY careful with these speakers, they were not even cranked up half-way.

Reviewed Aug 02nd, 2017 by bshingledecker

I have a set of these,,,or close. Mine are SM-150's. I bought them in 89 or so as well. I have had the mids replaced twice under warranty in the first few years, and have since re-surrounded the woofers. These still rock and will shake my house. Mids and highs, could be crisper, but are still good. I do not regret picking these up, and still have them in service on my main rig. Only drawback to me is the size. They are monsters.

Reviewed Mar 25th, 2017 by VintageGoodies

Great sounding pair, loud or low. Nice Bass and Treble! If you turn them up, beware as your neighbors may complain, these are awesome!
Not Recommended for apartments!

The person that reviewed previously, must have a Time Machine as they weren't available until 1996. So, there's no way they bought them in 1989.

Reviewed Nov 19th, 2014 by rmcdonaldjr

I have a pair of these infinity studio monitors I purchased them back in 1989 from a friend awesome quality and durability.



re: SM-155

A lowpoint for the Infinity brand, and certainly not a "Studio Monitor"! Very cheaply made. Big empty box with weak woofer, and badly made crossover. I have repaired several, so I know the construction well. Just allround cheap speaker, best avoided.

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