Klipsch Reference R-51PM
Powered bookshelf speakers with Bluetooth® and built-in phono preamp
Our take on the Klipsch Reference R-51PM by Crutchfield's Eric Angevine
No receiver required with these versatile speakers
Whenever I write about powered speakers, I talk about how you can connect just about anything and save space, because you don't need a receiver. All true, but I'd be remiss if I didn't point out that these Klipsch R-51PM speakers offer impressive sound, too.
Each features a 1" aluminum diaphragm compression tweeter matched with a 90° x 90° Tractrix® horn and a 5-1/4" woofer with the classic Klipsch spun-copper look. Rear bass ports make sure you hear the low notes while you're rocking out to your favorite tunes.
Now, about those connections
The right-hand speaker houses an amplifier that cranks out 60 watts of custom-tuned power per channel, and it's also where you'll find the plethora of inputs you'll use to connect other gear. The optical input is great for bolstering TV sound. There's an analog stereo RCA input with a line/phono switch so you can connect your turntable. Use the USB port to play tunes stored on your computer, or the 3.5mm aux input for your mobile device.
And of course, you can choose the ultra-convenient wireless streaming option, because there's Bluetooth built in.
There's also one very important output on the back of the speaker — a mono RCA for hooking up a powered subwoofer — like the Klipsch Reference R-8SW — to add deeper bass to music and movies.
My hands-on experience with the R-51PMs
Klipsch R-51PM powered speakers offer a plethora of inputs so you can connect sources without going through a receiver.
I'm a fan of Klipsch's powered speakers. I loved the Reference R-15PMs when I tested them out in my two-bedroom apartment a while back, so I was pleased to find, when I unboxed the R-51PMs, that they're significantly more compact, yet offer more built-in power.
Putting them to the test
It took me less than 15 minutes to set the speakers up in my master bedroom and start streaming music from my Spotify® account. They took up very little space on my combination dresser/entertainment furniture, but they produced clear sound that filled the room quite nicely.
I fiddled with their placement, moving them away from the wall until I was getting good, solid bass from the rear-firing ports. Then I went to town on an eclectic playlist — jumping from Debussy to Coltrane to Rage Against the Machine and beyond — to get a sense of how they'd perform.
The verdict? They sound as good as they look. I love that classic Klipsch spun-copper woofer and horn tweeter for both reasons. They come with magnetic grilles, but I opted to leave them off.
Using multiple sources
I like streaming tunes while I'm reading or doing light housework, but that's not all the RP-51PMs can do — not by a long shot. I hooked up the second TV to the optical input on the back of the right-hand speaker, and dialogue and sound effects became immediately more present and enjoyable.
I keep my turntable hooked up to the component system in my living room, but I like knowing that I can move it to my room and plug it straight into these powered speakers if I want to. With a teenaged son in the house who's not always super-careful with dad's audio equipment, that's a tempting notion.
I have a smaller set of near-field monitors that I love, but I think I'll move those to the desktop next to my computer. These Klipsch speakers offer the extra oomph — and that all-important phono stage — that I really crave when I'm hanging out in my personal space.
- Bluetooth technology for streaming from compatible devices
- built-in switchable phono preamp
- each speaker features:
- 1" aluminum diaphragm compression tweeter matched with a 90° x 90° Tractrix® horn
- 5-1/4" spun-copper woofer
- rear-firing bass-reflex port
- Dynamic Bass EQ gives you fuller bass at low volume
- 60 watts per channel via built-in amplifier (right speaker)
- frequency response: 68-21,000 Hz (±3dB)
- compact remote control included
Connections (back of right speaker):
- optical digital audio input (2-channel PCM only)
- RCA stereo analog audio input
- switch for selecting phono or line input
- USB Type B input for connecting your Mac® or PC
- stereo minijack input for mobile devices
- RCA mono output for optional powered subwoofer
Dimensions and Warranty:
- speaker dimensions: 5-15/16"W x 9-3/4"H x 7-1/2"D (each)
- weight: 23.4 lbs. (both)
- warranty: 1 year
- Our 60-day money-back guarantee
What's in the Box:
- Powered speaker (right)
- Passive speaker (left)
- 2 Grilles
- 68" AC power cord
- Remote control
- 2 "AAA" batteries
- 16' Length of 18AWG speaker wire (bare tinned wire on each end)
- 6.5' USB-A to USB-B cable
- 8 Self-adhesive rubber feet
- Instruction Booklet
Two-Way Driver Design: The Klipsch R-51PM powered bookshelf speakers deliver room-filling sound from a two-way driver design. Each speaker includes a 1" aluminum diaphragm compression driver with a Linear Travel Suspensions (LTS) mated to 90° x 90° square Tractrix Horn, and 5.25" copper spun magnetically shielded IMG woofer. The tweeter and woofer are crossed over at 1663Hz.
- LTS Aluminum Tweeter: Klipsch exclusive Linear Travel Suspension (LTS) aluminum tweeter minimizes distortion for enhanced, detailed performances. Using Kapton, an extremely light and rigid material, in the tweeter suspension provides high efficiency and improve resolution and detail.
- Tractrix Horn: The square Tractrix horn delivers a 90° x 90° dispersion pattern for a broader sound-stage.
- Copper Spun IMG Woofer: Each loudspeaker uses a copper spun IMG (Injection Molded Graphite) 5.25" woofer for accurate midrange and midbass performance.
Bass Reflex MDF Cabinet: The Klipsch R-51PM employs a bass reflex enclosure with a rear-firing port for greater efficiency and bigger bass response. The ported enclosure features a MDF cabinet finished with a a scratch-resistant, textured wood grain vinyl. The rigid MDF cabinet utilizes internal cross-bracing to minimize panel vibrations that can color sound. Each speaker also comes with a low profile magnetic grille.
Built-in Amplification: The Klipsch R-51PM's "Right Speaker" employs a built-in, ultra-low noise 50 watt x 2 channel amplifier to power both speakers in the system. The built-in amplifier has been custom deigned to maximize driver performance and eliminate the need for external amplification. The "Right Speaker" and "Left Speaker" are fitted with binding-post speaker terminals on the back of the cabinet and come with 16' of speaker wire (18AGW) to connect the speakers together.
Dynamic Bass EQ: As the human ear perceives frequencies differently with variations in output, the R-51PM will dynamically match the ear's ability to hear lower frequencies. Typically, only available with audio/video receivers, dynamic volume is a first for Klipsch powered monitors. What you get is powerful bass whether the listening volume is low, cranked up or somewhere in between.
Bluetooth Music Streaming: The Klipsch R-51PM active loudspeakers feature built-in Bluetooth A2DP/AVRCP technology which allows you to wirelessly stream audio from your Bluetooth-enabled source device - such as your smartphone, tablet, laptop, or computer. You'll be able to stream stored music or music apps from your Bluetooth-enabled device and control basic playback from the included remote control. Advanced playback control and song/artist information will still be done from your Bluetooth device. Once paired, the R-51PM will automatically re-connect with your device when in wireless range (up to 33').
Note: Due to the differences in Bluetooth technology, some Bluetooth enabled devices may be incompatible, function improperly, or may not support all features when used with the Klipsch R-51PM.
USB-B Input: The "Right Speaker" of the Klipsch R-51PM features a rear-panel USB (type-B) input for connecting your Windows PC or Mac computer/laptop. Through the R-51PM's USB connection, you are able to play music files (up to 24-bit/96kHz) stored on your Windows PC or Mac computer/laptop through the powered speaker system.
Optical Digital Input: The Klipsch R-51PM is fitted with an optical (toslink) digital input on the back of the "Right Speaker" for connection to a digital audio device like your TV, Blu-ray, or CD player. The speaker's optical digital input will accept 2ch stereo PCM only (up to 24-bit/96kHz).
Dual Analog Inputs w/ Phono Switch: The Klipsch R-51PM is equipped with two analog audio inputs on back of the "Right Speaker"; there is one stereo minijack (3.5mm) input for connecting a portable audio device with a headphone jack and one stereo RCA input for connecting an analog audio component. The stereo RCA input has a Phono switch which allows you to connect a turntable, so you can enjoy your vinyl record collection.
Sub Out: The Klipsch R-51PM features a mono-sub RCA output on the back of the "Right Speaker" that allows you to connect a powered subwoofer for added bass response. Your powered sub should have its own low-pass crossover.
IR Remote: The Klipsch R-51PM includes an IR wireless remote control for wireless operation of the powered speaker, plus control of your Bluetooth paired devices. The remote offers easy access to system features such as dedicated source selection, volume up/down, play/pause, and previous/next track. Make sure to point the IR remote at the IR sensor on the "Right Speaker".
Mounting Options: The Klipsch R-51PM can be placed on a speaker stand, bookshelf, table, or other flat surface. The powered bookshelf loudspeakers come with self-adhesive rubber feet to secure the speaker in place and prevent any damage to your stand's or shelf's surface. The rubber feet add approximately 0.125" to the overall height of the speaker.
Note: There is no included bracket, keyhole slot, or threaded insert to wall-mount the speaker.
AC Power: The Klipsch R-51PM's "Right Speaker" which is equipped with the built-in amplifier must be plugged into an AC power outlet using the included 68" detachable AC power cord.
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