In this review, we will be comparing RC85i and RC55i, two Passive In-wall speakers by Polk Audio Let's have a brief look at the main features
of Polk Audio RC85i and Polk Audio RC55i first before getting into our more
detailed comparison.
Polk Audio RC85i Key Specs
- 2-way Design
- 1" Hard-Dome Tweeter
- 8" Polypropylene Woofer
- 50-20kHz Frequency Response
- 90 dB Sensitivity
- Impedance: 8ohms
- Power Range:20-100watts
- Dimensions (H x W x D): 324.0" x 8.6875" x 3.5000"( 324.0 x 221.0 x 89.0mm )
Polk Audio RC55i Key Specs
- 2-way Design
- 0.75" Hard-Dome Tweeter
- 5.25" Polypropylene Woofer
- 70-20kHz Frequency Response
- 89 dB Sensitivity
- Impedance: 8ohms
- Power Range:20-100watts
- Dimensions (H x W x D): 245.0" x 6.1875" x 2.0120"( 245.0 x 158.0 x 52.0mm )
What size room are the Polk Audio RC85i and Polk Audio RC55i 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 RC85i |
Polk Audio RC55i |
| Near-field |
Average |
Average |
| Small Room |
Good |
Good |
| Mid-size Room |
Average |
Average |
| Large Room |
Poor |
Poor |
| Very Large Room |
Bad |
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 Polk Audio RC85i and Polk Audio RC55i 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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through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both RC85i and RC55i are 2-way speakers.
| Driver |
Polk Audio RC85i |
Polk Audio RC55i |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
0.75-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 8-inch
|
1 x 5.25-inch
|
RC85i features a 1" Hard-Dome Tweeter and 1 x 8" Polypropylene Woofer . On the other hand, the RC55i features a 0.75" Hard-Dome Tweeter and 1 x 5.25" Polypropylene Woofer .
Frequency Response
RC85i has a frequency range of 50-20kHz whereas RC55i has a frequency range of 70-20kHz. With a minimum frequency of 50Hz, the RC85i can go significantly deeper on the low side and provide stronger bass compared to the RC55i's min frequency of 70Hz.
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 In-wall class in our database.
Low Frequency
In-wall Speakers
High Frequency
In-wall 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.
Impedance and Sensitivity
RC85i and RC55i have the same Impedance of 8 ohms but where they differ is the sensitivity levels. RC85i sensitivity is rated at 90 dB and the RC55i's is at 89 dB. This 1 dB difference makes the Polk Audio RC85i a more sensitive speaker compared to Polk Audio RC55i, hence will play louder with the same amount of watts.
Sensitivity
In-wall Speakers
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.
RC85i and RC55i has the same power range of 20-100 watts.
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
RC85i features Spring clip type posts and RC55i has a Spring clip type posts. None of these speakers feature bi-amping/bi-wiring.
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 Polk Audio RC85i's and Polk Audio RC55i's external dimensions. Polk Audio RC85i has external dimensions of 324.0 x 221.0 x 89.0mm ( 12.7500-inch x 8.6875-inch x 3.5000-inch) whereas Polk Audio RC55i has external dimensions of 245.0 x 158.0 x 52.0mm ( 9.6250-inch x 6.1875-inch x 2.0120-inch) .
Polk Audio RC85i is clearly the larger of the two speakers. Its body is 63mm wider, 79mm taller and 37mm deeper than Polk Audio RC55i.
What's in the Box of Polk Audio RC85i?
Here are the items that are included inside the box of RC85i:
2 White in-wall speakers2 White grilles1 Cardboard Mounting TemplateOwners ManualOnline registration sheetProduct Registration Card
What's in the Box of Polk Audio RC55i?
Here are the items that come with the RC55i:
2 White in-wall speakers2 White grilles1 Cardboard Mounting TemplateOwners ManualOnline registration sheetProduct Registration Card
Sensitivity 
Woofer Size 
Height 
Base Surface Area 
Price per pair*