In this review, we will be comparing 65 RT and 255C-RT, two Passive In-wall speakers by Polk Audio.
Let's have a brief look at the main features
of Polk Audio 65 RT and Polk Audio 255C-RT first before getting into our more
detailed comparison.
| Key Specs | Polk Audio 65 RT | Polk Audio 255C-RT |
|---|
| Brand | Polk Audio
United States · founded 1972 | Polk Audio
United States · founded 1972 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Soft-Dome | 1" Soft-Dome |
|---|
| Woofer | 6.5" Polymer Composite | 2 x 5.25" Polymer Composite |
|---|
| Frequency response | 50-25kHz | 50-25kHz |
|---|
| Sensitivity | 90 dB | 90 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 10-125 watts | 10-150 watts |
|---|
| Dimensions (H x W x D) | 12.7500" x 7.2500" x 3-1/2"
324.0 x 185.0 x 88.9mm | 7.5625" x 13.0625" x 3-7/8"
193.0 x 332.0 x 98.4mm |
|---|
65 RT and 255C-RT are members of Polk Audio's RT series of speakers. Below you can find the loudspeakers from this series.
Polk Audio RT Series
History
What size room are the Polk Audio 65 RT and Polk Audio 255C-RT 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 Audio 65 RT |
Polk Audio 255C-RT |
| Near-field |
Poor |
Poor |
| Small Room |
Average |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Average |
Average |
| Very Large Room |
Poor |
Poor |
(* 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 65 RT and 255C-RT are 2-way speakers.
Polk Audio 65 RTPolk Audio 255C-RT
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 Audio 65 RT |
Polk Audio 255C-RT |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 6.5-inch
|
2 x 5.25-inch
|
65 RT features a 1" Soft-Dome Tweeter and 1 x 6.5" Polymer Composite Woofer. On the other hand, the 255C-RT features a 1" Soft-Dome Tweeter and 2 x 5.25" Polymer Composite Woofer.
Frequency Response
65 RT and 255C-RT has exactly the same frequency range of 50-25kHz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the In-wall class in our database.
Low Frequency
In-wall 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
65 RT and 255C-RT have the same Impedance of 8 ohms and their sensitivity is also same at 90 dB.
Sensitivity
In-wall 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.
255C-RT can handle a max power of 150 watts RMS, whereas 65 RT has a max power handling value of 125 watts RMS, 25 watts less than the 255C-RT.
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
65 RT features Spring post type posts and 255C-RT has a Spring post type posts. None of these speakers feature bi-amping/bi-wiring.
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 Audio 65 RT's and Polk Audio 255C-RT's external dimensions. Polk Audio 65 RT has external dimensions of 324.0 x 185.0 x 88.9mm (12.7500-inch x 7.2500-inch x 0.0000-inch) whereas Polk Audio 255C-RT has external dimensions of 193.0 x 332.0 x 98.4mm (7.5625-inch x 13.0625-inch x 0.0000-inch).
Polk Audio 65 RT is 147mm narrower and 9.5mm less deeper than Polk Audio 255C-RT but it is also 131mm taller.
What's in the Box of Polk Audio 65 RT?
Here are the items that are included inside the box of 65 RT:
- Rectangular in-wall speaker
- Foam rubber port plug
- White metal grille
- Mounting template
- Owners Manual
- Sheer-Grille Painting instructions
- Online Registration Card
- Polk Audio product brochure
What's in the Box of Polk Audio 255C-RT?
Here are the items that come with the 255C-RT:
- In-wall center-channel loudspeaker
- White metal grille
- Mounting template
- Owners Manual
- Sheer-Grille Painting instructions
- Online Registration Card
- Polk Audio product brochure