In this review, we will be comparing ES50 and RP-4000F, two Passive Floor-standing speakers from Polk Audio and Klipsch.
Let's have a brief look at the main features
of Polk ES50 and Klipsch RP-4000F first before getting into our more
detailed comparison.
| Key Specs | Polk ES50 | Klipsch RP-4000F |
|---|
| Brand | Polk Audio
United States · founded 1972 | Klipsch
United States · founded 1946 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Soft-Dome | 1" Tractrix Horn |
|---|
| Woofer | 2 x 5.25" Mica-reinforced polypropylene | 2 x 4" Cerametallic |
|---|
| Frequency response | 38-40k Hz | 37-25k Hz |
|---|
| Sensitivity | 88 dB | 95 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 40-200 watts | up to 75 watts |
|---|
| Weight | 14.50kg / 31.9lbs | 13.18kg / 29lbs |
|---|
| Dimensions (H x W x D) | 37-7/16" x 7-1/2" x 11-1/16"
951.0 x 191.0 x 281.0mm | 34-1/4" x 7-3/8" x 11-3/8"
870.0 x 188.0 x 289.0mm |
|---|
What size room are the Polk ES50 and Klipsch RP-4000F 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* |
Polk ES50 |
Klipsch RP-4000F |
| Near-field |
Bad |
Poor |
| Small Room |
Poor |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Good |
Average |
| Very Large Room |
Poor |
No way |
(* 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.)
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both ES50 and RP-4000F are 2-way speakers.
Polk ES50Klipsch RP-4000F
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Polk ES50 |
Klipsch RP-4000F |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 5.25-inch
|
2 x 4-inch
|
ES50 features a 1" Terylene High-Res Soft-Dome Tweeter and 2 x 5.25" Mica-reinforced polypropylene Woofer with a Crossover frequency at 2500Hz. On the other hand, the RP-4000F features a 1" Tractrix Horn Tweeter and 2 x 4" Cerametallic Woofer with a Crossover frequency at 1500 Hz.
Frequency Response
ES50 has a frequency range of 38-40k Hz whereas RP-4000F has a frequency range of 37-25k Hz. With a minimum frequency of 37Hz, the RP-4000F can go slightly deeper then the ES50's min frequency of 38Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Floor-standing class in our database.
Low Frequency
Floor-standing Speakers
Neither pair reaches down to 20Hz, the usual definition of full-range, which is normal for speakers of this size. If you want the bottom octave for movies or bass-heavy music, add a subwoofer to whichever you choose. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
ES50 and RP-4000F have the same Impedance of 8 ohms but where they differ is the sensitivity levels. ES50 sensitivity is rated at 88 dB and the RP-4000F's is at 95 dB. This 7 dB difference makes the Klipsch RP-4000F a more sensitive speaker compared to Polk ES50, hence will play louder with the same amount of watts.
Sensitivity
Floor-standing Speakers
Power Range
Power
range is the range of input power in watts RMS that a loudspeaker is designed to handle. Staying
within that range gives nominal performance; driving the speaker beyond its maximum wattage can damage it.
ES50 can handle a max power of 200 watts RMS, whereas RP-4000F has a max power handling value of 75 watts RMS, 125 watts less than the ES50.
Note that higher power handling does not make a speaker louder: that depends mainly on
sensitivity and impedance. The calculator below shows how loud each of these actually plays
on a real amplifier.
Which plays louder on your amplifier?
Starting with a popular amplifier - change it to the one you own, or any you are
considering, and watch both numbers move.
Input Type and Bi-Amping / Bi-Wiring
Both ES50 and RP-4000F features dual binding post speaker terminals for bi-amping or bi-wiring.
Cabinet Type and Port Position
ES50 has a bottom firing port whereas RP-4000F has a rear firing ports. Polk ES50's bottom-firing port gives more flexibility in placement in regards to proximity to walls compared to Klipsch RP-4000F with its rear-firing port.
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Polk ES50's and Klipsch RP-4000F's external dimensions. Polk ES50 has external dimensions of 951.0 x 191.0 x 281.0mm (37-7/16 x 7-1/2 x 11-1/16inch) whereas Klipsch RP-4000F has external dimensions of 870.0 x 188.0 x 289.0mm (34-1/4 x 7-3/8 x 11-3/8inch).
Klipsch RP-4000F is 3mm narrower and 81mm shorter than Polk ES50 but it is also 8mm deeper.
Below you can see the front view size comparison of Polk ES50 and Klipsch RP-4000F in scale.
Comparison image of Polk ES50 and Klipsch RP-4000F 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 Polk ES50 is approximately 536.7cm2 / 83.2inch2 and base area of the Klipsch RP-4000F is approximately 543.3cm2 / 84.2inch2. The ES50 requires 1% less surface area than the RP-4000F which gives it a small advantage 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 Polk ES50 weighs 14.50kg / 31.9lbs and the Klipsch RP-4000F weighs 13.18kg / 29lbs. This makes the ES50 10% heavier than the RP-4000F.
Here is a comparison of how ES50 and RP-4000F's weights compare with the average, max and min weights in Passive Floor-standing class.
Weight
All Floor-standing Speakers
What's in the Box of Polk ES50?
Here are the items that are included inside the box of ES50:
- Floorstanding loudspeaker
- Grille (attached)
- 4 Feet (pre-installed)
- Owners Manual
- Online Product Registration
What's in the Box of Klipsch RP-4000F?
Here are the items that come with the RP-4000F:
- Floorstanding loudspeaker
- Stabilizer feet (installed)
- Grille (installed)
- 2 Terminal jumpers (installed)
- User Manual
- Important Safety Instructions
- Warranty Information
 Max Input Power |
200 watts
vs
75 watts
|
Handle more power from your amplifier |
 Woofer Size |
5.25 inches
vs
4 inches
|
Larger woofer |
 High Frequency Response |
40k Hz
vs
25k Hz
|
Generates higher frequency |
 Base Surface Area |
536cm2
vs
543cm2
|
Takes less floor space |
 Sensitivity |
95 dB
vs
88 dB
|
Play louder with same amount of amplification power |
|
Low Frequency Response |
37 Hz
vs
38 Hz
|
Generates deeper bass |
 Height |
870mm
vs
951mm
|
Easier to fit in smaller spaces |
| General |
Polk Audio Signature Elite ES50 |
Klipsch Reference Premiere RP-4000F |
| Brand |
Polk Audio |
Klipsch |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
40-200 watts |
up to 75 watts |
| Sensitivity |
88 dB |
95 dB |
| Impedance |
8 ohms |
8 ohms |
| Frequency Response |
38-40k Hz |
37-25k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5.25" |
4" |
| Woofer Composition |
Mica-reinforced polypropylene |
Cerametallic |
| Woofer Surround Material |
Butyl rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Soft-Dome |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2500Hz |
1500 Hz |
| Firing Direction |
bottom |
rear |
Physical Specs |
|
|
| Height |
951.0mm (37.4") |
870.0mm (34.3") |
| Width |
191.0mm (7.5") |
188.0mm (7.4") |
| Depth |
281.0mm (11.1") |
289.0mm (11.4") |
| Weight |
14.50kg (31.9lbs) |
13.18kg (29lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF, Wood-grain vinyl |
MDF/Wood-grain vinyl |
| Available Colors |
Black |
Walnut, Black |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
Yes |
Yes |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |
No single best speaker here - they are built to different priorities, and the right one depends on your room, your amplifier and what you listen to.
| Area | Better | Why |
|---|
| Bass | evenly matched | Much the same reach (38Hz vs 37Hz). |
| Amplifier needs | B | Klipsch RP-4000F is more sensitive (95dB vs 88dB), so it goes louder on the same amplifier. |
| Headroom | A | Polk ES50 takes more power (200W vs 75W) - more in hand in a big room. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | depends | Polk ES50: bi-amping; Klipsch RP-4000F: bi-amping. Klipsch RP-4000F sits in a wider range (17 models), so a matched surround system is easier later. |
| Price | evenly matched | Much the same money ($698 vs $698 a pair). |
A Polk ES50 B Klipsch RP-4000F
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Neither runs away with it - they trade advantages. Let the "depends" rows and your own room settle it. Match it to your room: we rate Polk ES50 the better fit for a large room, and Klipsch RP-4000F for a small room. If your amplifier is modest, vintage or valve-based, Klipsch RP-4000F is the safer partner - the other will want more current or more watts to sound its best.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.