Design and build quality:

Comparing KEF Q150 vs Klipsch R-51M, the R-51M is larger. The scratch-protected enclosure of Klipsch R-51M is great if you have cats at home. It has an MDF cabinet and is designed to get rid of any vibration or coloration. A standard black finish is available which blends in with any room decor. 

Compared to other standard bookshelf speakers, KEF Q150 is lightweight and has a slim profile. It is available in Satin Black, Satin White and Walnut. The speakers sit on rubber feet that give stability when you place it on a table or shelf.

Performance:

Comparing KEF Q150 vs Klipsch R-51M, the R-51M has higher sensitivity. This means it can get louder. They both have 1” tweeter and 5.25” woofer. However, Polk R200 has an uncommon speaker arrangement where the tweeter lies in the middle of the woofer. This is known to produce more precise sound throughout a broader space. The drivers are made of aluminum that work to ensure extremely clear and smooth highs. Bass response is powerful and packs a punch. 

A port foam plug is available to block the ports in case the bass sounds inaccurate and boomy. The speakers are easy to drive with an impedance of 8 ohms. This means you do not have to look hard for power hungry receivers. KEF Q150 boasts an impactful soundstage. It has a broad sweet spot and good directivity. The crossover is selected in such a way that the transition sounds smooth and natural. 

Klipsch RP-51M also has 1” tweeter and 5.25” woofer. It has Klipsch patented Tractrix Horn and IMG woofer. The highs are focused and delivered just at the listening spot. Woofers have good rigidity and produce great bass. The flared port helps in this case. Although we feel the bass is adequate from a bookshelf speaker, bass heads might need an additional subwoofer.

We listened to jazz, rock, classic, metal music genres with these and were pretty impressed by the performance. When paired with a center channel, the speakers sound great as we play movies. It is capable of delivering a lively sound and has good dynamics. Both Klipsch R-51M and KEF Q150 have binding posts that you will use to connect receivers. Then with the receiver you can add additional speakers like the receiver or amplifier. 

Compatible devices:

You can connect other speakers from the KEF Q series with the Q150: Q550/Q750/Q950 floorstanding, Q350 bookshelf, Q650C/Q250C center channel, Q50A Atmos speakers and subwoofer. The following listed receivers are compatible with this speaker: Onkyo TX-8270, Anthem MRX 1120, etc.

For Klipsch R-51M, the following speakers are available: Klipsch R-610F/R-620F/R-820F/R-625FA floorstanding R-41 bookshelf, R-34C/R-52C center channel, R-41SA Atmos and subwoofer. There is permissibility for mismatching speakers and subwoofers with other brands. For amps or receivers, choose one from the list: Onkyo TX-2500, Onkyo TX-8220, Sony STR-DN1080, Yamaha RX-V675, Emotiva TA-100, Denon AVR-S750, Marantz NR1510, Yamaha RX-V371, Pioneer SX-850, Cambridge AXR85, Yamaha RX-A2A, etc.

Speaker positioning: 

KEF claims you can place the speakers within 6 to 10’ and elevate them at a height of 18-24”. The distance from the back wall should be around 10” and the sidewall is 40”.

Like other Klipsch speakers, the R-51M should have a gap of 6 to 15’ between them. You can keep the distance between the speaker and user equal or increase it. For rear placements, elevate them around 2’.

Cost:

KEF Q150 vs Klipsch R-51M price comparison shows the Klipsch R-51M is the more affordable one. The R-51M is found under $250 whereas the KEF Q150 is available for under $350. 

FAQ:

Can I place Klipsch R-51M in large rooms?

Klipsch R-51M speakers are suitable to use in compact spaces, like small to medium sized rooms. While you can place them in large spaces, it might affect the performance. They may appear to be ‘tinny’ so we suggest expanding it to 3.1 or 5.1 systems in large rooms.