In this review, we will be comparing R-51PM and R-15PM, two Powered Bookshelf speakers by Klipsch. Being Powered speakers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them. Let's have a brief look at the main features of Klipsch R-51PM and Klipsch R-15PM first before getting into our more detailed comparison.
In the following sections, we will get into details in order to better understand how Klipsch R-51PM and Klipsch R-15PM compares and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
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Both R-51PM and R-15PM are 2-way speakers. R-51PM features a 1.0" Aluminum LTS Tractrix Horn Tweeter and 1 x 5.25" Copper-spun IMG Woofer with a Crossover frequency at 1663Hz. On the other hand, R-15PM features a 1.0" Aluminum Hard-Dome Tweeter and 1 x 5.25" Copper-spun IMG Woofer with a Crossover frequency at 1800Hz.
R-51PM has a frequency range of 68-21k Hz whereas R-15PM has a frequency range of 62-24k Hz. With a minimum frequency of 62Hz, the R-15PM can go significantly deeper on the low side and provide stronger bass compared to the R-51PM's min frequency of 68Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers under Bookshelf class in our database.
Cabinet Type and Port Position
Both R-51PM and R-15PM have rear firing ports. Rear ported speakers generlly need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing too close to the walls may cause the bass to sound boomy.
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 Klipsch R-51PM's and Klipsch R-15PM's external dimensions. Klipsch R-51PM has external dimensions of 330.2 x 179.4 x 260.3mm ( 13 x 7.0625 x 10.25inch) whereas Klipsch R-15PM has external dimensions of 317.5 x 177.8 x 250.8mm ( 12.5 x 7 x 9.875inch) .
Klipsch R-51PM is clearly the larger of the two speakers. Its body is 1.6mm wider, 12.7mm taller and 9.5mm deeper than Klipsch R-15PM.
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 Klipsch R-51PM is approximately 467.0cm2 / 72.4inch2 and base area of the Klipsch R-15PM is approximately 445.9cm2 / 69.1inch2. The R-51PM requires 5% more surface area than the R-15PM which gives it a small disadvantage on placement in tight spaces.