In this review, we will be comparing Mackie CR4-XBT and R-51M, two Bookshelf speakers from Mackie and Klipsch. The main difference between these two speakers is that the Mackie CR4-XBT is a Powered speaker which means that it has a built-in amplifier inside the speaker body so you don't need an external power amp or an integrated amp whereas the Klipsch R-51M is a Passive speaker so has to be matched with an amplifier to get any sound from it. Let's have a brief look at the main features
of Mackie CR4-XBT and Klipsch R-51M first before getting into our more
detailed comparison.
Mackie CR4-XBT Key Specs
- 2-way Design
- 25-watt RMS( 50-watt Peak) Integrated Amplifier
- 0.75" Dome Tweeter
- 4" Polypropylene Woofer
- 65-20k Hz Frequency Response
- N/A Max Depth / N/A Max Sample Rate
- Built-in 4.2 Bluetooth
- Dimensions (H x W x D): 222.3" x 6.125" x 8.5"( 222.3 x 155.6 x 215.9mm )
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 )
In the following sections, we will get into more detail in order to better understand how the Mackie CR4-XBT 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.
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Drivers
Both Mackie CR4-XBT and R-51M are 2-way speakers.
| Driver |
Mackie CR4-XBT |
Klipsch R-51M |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
0.75-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 4-inch
|
1 x 5.25-inch
|
Mackie CR4-XBT features a 0.75" Silk Dome Tweeter and 1 x 4" Polypropylene Woofer . 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
Mackie CR4-XBT has a frequency range of 65-20k Hz whereas R-51M has a frequency range of 62-21k Hz. With a minimum frequency of 62Hz, the R-51M can go slightly deeper then the Mackie CR4-XBT's min frequency of 65Hz.
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
High Frequency
Bookshelf Speakers
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.
Cabinet Type and Port Position
Both Mackie CR4-XBT 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 Mackie CR4-XBT's and Klipsch R-51M's external dimensions. Mackie CR4-XBT has external dimensions of 222.3 x 155.6 x 215.9mm ( 8.75 x 6.125 x 8.5inch) whereas Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm ( 13.3 x 7.0 x 8.4inch) .
Mackie CR4-XBT is 22.4mm narrower and 115.7mm shorter than Klipsch R-51M but it is also 0.90000000000001mm deeper.
Below you can see the front view size comparison of Mackie CR4-XBT and Klipsch R-51M in scale.
Comparison image of Mackie CR4-XBT and Klipsch R-51M Size and External Dimensions
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 Mackie CR4-XBT is approximately 335.9cm2 / 52.1inch2 and base area of the Klipsch R-51M is approximately 382.7cm2 / 59.3inch2. The Mackie CR4-XBT requires 12% less surface area than the R-51M which gives it a small advantage on placement in tight spaces.
Here is an another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:
Size Comparison image of Mackie CR4-XBT and Klipsch R-51M on a Media Console
What's in the Box of Mackie CR4-XBT?
Here are the items that are included inside the box of Mackie CR4-XBT:
Powered monitor w/ attached 5.5-feet power cord (C7 unpolarized)Passive monitor6.5-feet Speaker wire5-feet Stereo mini to RCA cableQuick Start Guide
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
Speaker Type 
Height 
Base Surface Area 
Price per pair* 
RCA Connection 
Woofer Size 
High Frequency Response