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PSB Imagine XB vs Klipsch R-51M Comparison

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PSB Imagine XB

Passive Bookshelf | 55-23k Hz

PSB Imagine XB
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Klipsch R-51M

Passive Bookshelf | 62-21k Hz

Klipsch Reference R-51M
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PSB Imagine XB PSB Imagine XB
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Klipsch R-51M Klipsch R-51M
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PSB Imagine XB
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Klipsch R-51M
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PSB Imagine XB vs Klipsch R-51M Speaker Comparison

In this review, we will be comparing Imagine XB and R-51M, two Passive Bookshelf speakers from PSB and Klipsch.

Let's have a brief look at the main features of PSB Imagine XB and Klipsch R-51M first before getting into our more detailed comparison.

PSB Imagine XB Key Specs

  • 2-way Design
  • 1" Hard-Dome Tweeter
  • 5.25" Clay/Ceramic/Poly Woofer
  • 55-23k Hz Frequency Response
  • 87 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:20-150watts
  • Weight:5.60kg
  • Dimensions (H x W x D): 302.0" x 6.75" x 10.75"( 302 x 170 x 271mm )

Klipsch R-51M Key Specs

  • 2-way Design
  • 1" Tractrix Horn Tweeter
  • 5.25" Copper-spun IMG Woofer
  • 62-21k Hz Frequency Response
  • 93 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:Up to 85watts
  • Weight:5.00kg
  • Dimensions (H x W x D): 338.0" x 7.0" x 8.4"( 338.0 x 178.0 x 215.0mm )

What size room are the PSB Imagine XB and Klipsch R-51M speakers good for?

The size of the room in which you are planning to use these loudspeakers is an important decision factor. Here we have compared their suitability to various sizes of environments considering their size and max power parameters:

Listening Environment* PSB Imagine XB Klipsch R-51M
Near-field Poor Average
Small Room Average Good
Mid-size Room Good Average
Large Room Average Poor
Very Large Room Poor Bad

(* Approximate Room sizes: Small < 100sq. ft / 9 m2, Mid-size: 100-220 sq. ft / 9-20 m2, Large 220-400 sq. ft / 20-36 m2, Very Large: > 400 sq. ft / 36 m2. Average Floor Height: 9" / 2.7m. Typical room sizes differ from country to country, and the actual listening experience changes depending on floor height, room shape, surface materials, listening position, speaker locations, etc.)

In the following sections, we will get into more detail in order to better understand how the PSB Imagine XB and Klipsch R-51M compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.


**This post contains affiliate links, and I will be compensated if you make a purchase after clicking through my links. As an Amazon Associate I earn from qualifying purchases.


Drivers

Both Imagine XB and R-51M are 2-way speakers.

Driver PSB Imagine XB Klipsch R-51M
Driver Setup 2-way 2-way
Tweeter 1-inch 1-inch
Midrange - -
Woofer 1 x 5.25-inch 1 x 5.25-inch

Imagine XB features a 1" Titanium Dome with Ferrofluid Hard-Dome Tweeter and 1 x 5.25" Clay/Ceramic/Poly Woofer with a Crossover frequency at 1800Hz. On the other hand, the R-51M features a 1" Tractrix Horn Tweeter and 1 x 5.25" Copper-spun IMG Woofer with a Crossover frequency at 1660Hz.

Frequency Response

Imagine XB has a frequency range of 55-23k Hz whereas R-51M has a frequency range of 62-21k Hz. With a minimum frequency of 55Hz, the Imagine XB can go significantly deeper on the low side and provide stronger bass compared to the R-51M's min frequency of 62Hz.

Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Bookshelf class in our database.

Low Frequency

Bookshelf Speakers

Imagine XB
R-51M
Min
Average
Max
High Frequency

Bookshelf Speakers

PSB Imagine XB
Klipsch R-51M
Min
Average
Max

None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.

Impedance and Sensitivity

Imagine XB and R-51M have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Imagine XB sensitivity is rated at 87 dB and the R-51M's is at 93 dB. This 6 dB difference makes the Klipsch R-51M a more sensitive speaker compared to PSB Imagine XB, hence will play louder with the same amount of watts.

Sensitivity

Bookshelf Speakers

Imagine XB
R-51M
Min
Average
Max

Power Range

Power range is the range of input power in watts RMS that a loudspeaker is designed to handle. While using an amplifier within this range ensures the nominal performance , inputting a power that is higher than the max wattage can result in a damaged speaker.

Imagine XB can handle a max power of 150 watts RMS from the amp the whereas R-51M has a max power handling value of 85 watts RMS, 65 watts less than the Imagine XB.

Keep in mind that a higher max power handling value doesn't necessarily make that a louder speaker compared to a lower max handling speaker. Loudness or the sound level is also impacted by parameters such as Impedance, sensitivity and system efficiencies.

Input Type and Bi-Amping / Bi-Wiring

Imagine XB features Single Gold Plated Binding Posts - 5-way type posts and R-51M has a Single Gold Plated Binding Posts - 5-way type posts. None of these speakers feature bi-amping/bi-wiring.

Klipsch R-51MSingle Gold Plated Binding Posts - 5-way Terminals
Klipsch R-51M's Single Gold Plated Binding Posts - 5-way terminals

Cabinet Type and Port Position

Both Imagine XB and R-51M have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.

If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.

Physical Specs

Size of a speaker can sometimes become an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare PSB Imagine XB's and Klipsch R-51M's external dimensions. PSB Imagine XB has external dimensions of 302 x 170 x 271mm ( 12inch x 6.75inch x 10.75inch ) whereas Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm ( 13.3 x 7.0 x 8.4inch) .

PSB Imagine XB is 8mm narrower and 36mm shorter than Klipsch R-51M but it is also 56mm deeper.

Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited. The base surface area of the PSB Imagine XB is approximately 460.0cm2 / 71.3inch2 and base area of the Klipsch R-51M is approximately 382.7cm2 / 59.3inch2. The Imagine XB requires 20% more surface area than the R-51M which gives it a small disadvantage on placement in tight spaces.

Weight Comparison

The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The PSB Imagine XB weighs 5.60kg / 12.3lbs and the Klipsch R-51M weighs 5.00kg / 11lbs. This makes the Imagine XB 12% heavier than the R-51M.

Here is a comparison of how Imagine XB and R-51M's weights compare with the average, max and min weights in Passive Bookshelf class.

Weight
All Bookshelf Speakers
PSB Imagine XB
Klipsch R-51M
Min
Average
Max

What's in the Box of PSB Imagine XB?

Here are the items that are included inside the box of Imagine XB:
  • 2 Bookshelf loudspeakers
  • 2 Grilles
  • 8 Rubber feet
  • Quick Start Guide
  • Warranty Card
  • What's in the Box of Klipsch R-51M?

    Here are the items that come with the R-51M:
  • 2 Bookshelf loudspeakers
  • 2 Grilles (installed)
  • 8 Self-adhesive rubber feet
  • Quick Setup Guide
  • Important Safety Instructions
  • Warranty Information

  • Reasons to choose PSB Imagine XB over Klipsch Reference R-51M
    Max Input Power 150 watts vs 85 watts Handle more power from your amplifier
    Low Frequency Response 55 Hz vs 62 Hz Generates deeper bass
    High Frequency Response 23k Hz vs 21k Hz Generates higher frequency
    Height 302mm vs 338mm Easier to fit in smaller spaces

    Reasons to choose Klipsch Reference R-51M over PSB Imagine XB

    Sensitivity 93 dB vs 87 dB Play louder with same amount of amplification power
    Base Surface Area 382cm2 vs 460cm2 Takes less floor space
    Price per pair* 359USD vs 649USD costs less (*prices may change depending on the seller, location and time)
    PSB Imagine XB vs Klipsch R-51M Specs Table
    Detailed comparison of specifications
    General PSB Imagine XB Klipsch Reference R-51M
    Brand PSB Klipsch
    Speaker Type Bookshelf speakers Bookshelf speakers
    Power Range 20-150 watts Up to 85 watts
    Sensitivity 87 dB 93 dB
    Impedance 8 ohms 8 ohms
    Impedance 4 ohms n/a
    Frequency Response 55-23k Hz 62-21k Hz
    Drivers
    Woofer Quantity 1 1
    Woofer Size 5.25" 5.25"
    Woofer Composition Clay/Ceramic/Poly Copper-spun IMG
    Woofer Surround Material Rubber Rubber
    Tweeter Size 1" 1"
    Tweeter Type Hard-Dome Tractrix Horn
    Aimable Tweeter No No
    Midrange Driver No No
    Crossover Frequency 1800Hz 1660Hz
    Firing Direction rear rear
    Physical Specs
    Height 302.0mm (11.9") 338.0mm (13.3")
    Width 170.0mm (6.7") 178.0mm (7")
    Depth 271.0mm (10.7") 215.0mm (8.5")
    Weight 5.60kg (12.3lbs) 5.00kg (11lbs)
    Enclosure Bass Reflex Bass Reflex
    Finish MDF/Wood-grain MDF/Wood-grain vinyl
    Available Colors Black Black
    Mounting Bracket No
    Recommended Stand Height 24-26" 24-28"
    Grille Yes Yes
    Moisture Resistancy No No
    Connections
    Biamp Inputs No No
    Other
    Parts Warranty 5 Years 5 Years
    Labor Warranty 5 Years 5 Years

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