In this review, we will be comparing CSi A6 and ES30, two Passive Center Channel speakers by Polk Audio.
Let's have a brief look at the main features
of Polk CSi A6 and Polk ES30 first before getting into our more
detailed comparison.
| Key Specs | Polk CSi A6 | Polk ES30 |
|---|
| Brand | Polk Audio
United States · founded 1972 | Polk Audio
United States · founded 1972 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Dynamic Balance | 1" High-res dome |
|---|
| Woofer | 2 x 6.5" Dynamic Balance polymer composite | 2 x 5.5" mica-reinforced polypropylene Dynamic Balance |
|---|
| Frequency response | 55-26k Hz | 55-40k Hz |
|---|
| Sensitivity | 90 dB | 89 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 20-200 watts | 20-125 watts |
|---|
| Weight | 13.18kg / 29lbs | 8.64kg / 19lbs |
|---|
| Dimensions (H x W x D) | 7-13/16" x 24-1/16" x 14-1/4"
199.0 x 612.0 x 362.0mm | 7-1/2" x 20-1/16" x 10-5/8"
191.0 x 510.0 x 270.0mm |
|---|
What size room are the Polk CSi A6 and Polk ES30 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 CSi A6 |
Polk ES30 |
| 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 CSi A6 and ES30 are 2-way speakers.
Polk CSi A6Polk ES30
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 CSi A6 |
Polk ES30 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 6.5-inch
|
2 x 5.5-inch
|
CSi A6 features a 1" silk/polymer Dynamic Balance Tweeter and 2 x 6.5" Dynamic Balance polymer composite Woofer. On the other hand, the ES30 features a 1" Terylene High-res dome Tweeter and 2 x 5.5" mica-reinforced polypropylene Dynamic Balance Woofer.
Frequency Response
CSi A6 has a frequency range of 55-26k Hz whereas ES30 has a frequency range of 55-40k Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Center Channel class in our database.
Low Frequency
Center Channel 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
CSi A6 and ES30 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. CSi A6 sensitivity is rated at 90 dB and the ES30's is at 89 dB. This 1 dB difference makes the Polk CSi A6 a more sensitive speaker compared to Polk ES30, hence will play louder with the same amount of watts.
Sensitivity
Center Channel 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.
CSi A6 can handle a max power of 200 watts RMS, whereas ES30 has a max power handling value of 125 watts RMS, 75 watts less than the CSi A6.
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
CSi A6 features 5-Way post type posts and ES30 has a 5-Way post type posts. None of these speakers feature bi-amping/bi-wiring.
Polk CSi A6's 5-Way post terminals
Polk ES30's 5-Way post terminals
Cabinet Type and Port Position
Both CSi A6 and ES30 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.
Polk ES30 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 CSi A6's and Polk ES30's external dimensions. Polk CSi A6 has external dimensions of 199.0 x 612.0 x 362.0mm (7-13/16 x 24-1/16 x 14-1/4inch) whereas Polk ES30 has external dimensions of 191.0 x 510.0 x 270.0mm (7-1/2 x 20-1/16 x 10-5/8inch).
Polk CSi A6 is clearly the larger of the two speakers. Its body is 102mm wider, 8mm taller and 92mm deeper than Polk ES30.
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 CSi A6 is approximately 2215.4cm2 / 343.4inch2 and base area of the Polk ES30 is approximately 1377.0cm2 / 213.4inch2. The CSi A6 requires 61% more surface area than the ES30 which gives it a small disadvantage 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 CSi A6 weighs 13.18kg / 29lbs and the Polk ES30 weighs 8.64kg / 19lbs. This makes the CSi A6 53% heavier than the ES30.
Here is a comparison of how CSi A6 and ES30's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
What's in the Box of Polk CSi A6?
Here are the items that are included inside the box of CSi A6:
- One cherry center channel speaker
- One 9.5-inch kickstand
- One 5.5-inch kickstand (installed)
- 4 Self-adhesive rubber feet
- Owners Manual
- Online registration sheet
- Polk Audio product brochure
What's in the Box of Polk ES30?
Here are the items that come with the ES30:
- Center-channel loudspeaker
- Grille (attached)
- 4 Self-adhesive rubber feet
- Owners Manual
- Online Product Registration
 Max Input Power |
200 watts
vs
125 watts
|
Handle more power from your amplifier |
 Sensitivity |
90 dB
vs
89 dB
|
Play louder with same amount of amplification power |
 Woofer Size |
6.5 inches
vs
5.5 inches
|
Larger woofer |
 High Frequency Response |
40k Hz
vs
26k Hz
|
Generates higher frequency |
 Height |
191mm
vs
199mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1377cm2
vs
2215cm2
|
Takes less floor space |
 Price per pair* |
299USD
vs
399USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Polk Audio CSi A6 |
Polk Audio Signature Elite ES30 |
| Brand |
Polk Audio |
Polk Audio |
| Speaker Type |
Center channel speaker (Cherry) |
Center channel speaker |
| Power Range |
20-200 watts |
20-125 watts |
| Sensitivity |
90 dB |
89 dB |
| Impedance |
8 ohms |
8 ohms |
| Frequency Response |
55-26k Hz |
55-40k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
6.5" |
5.5" |
| Woofer Composition |
Dynamic Balance polymer composite |
mica-reinforced polypropylene Dynamic Balance |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Dynamic Balance |
High-res dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
199.0mm (7.8") |
191.0mm (7.5") |
| Width |
612.0mm (24.1") |
510.0mm (20.1") |
| Depth |
362.0mm (14.3") |
270.0mm (10.6") |
| Weight |
13.18kg (29lbs) |
8.64kg (19lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
n/a |
MDF, Wood-grain vinyl |
| Available Colors |
Black, Cherry |
Black, Walnut, White |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |
A generation apart: Polk ES30 is the newer design, against a 2008 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | evenly matched | Much the same reach (55Hz vs 55Hz). |
| Amplifier needs | evenly matched | Similar sensitivity (90dB vs 89dB) - both want much the same power. |
| Headroom | A | Polk CSi A6 takes more power (200W vs 125W) - more in hand in a big room. |
| Size | depends | Polk ES30 is easier to place; Polk CSi A6 is bigger, which usually goes with fuller bass. Your room decides. |
| Price | B | Polk ES30 is cheaper - $299 against $399, about 25% less. |
A Polk CSi A6 B Polk ES30
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?
Polk CSi A6 is ahead, but only on 1 of the measured areas, and it costs about 33% more. That is a lot of money for a narrow margin on paper - Polk ES30 looks like the sensible buy unless something else about the Polk CSi A6 appeals to you. In a large or open-plan room, Polk CSi A6 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Polk ES30 is the easier speaker to get right. Think about the whole system, not just the speakers: the roughly $100 saved by taking the cheaper pair would buy a subwoofer or a better amplifier, and either usually does more for the sound than the difference between these two.
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.