In this review, we will be comparing Foundation C1 and R400, two Passive Center Channel speakers from MartinLogan and Polk Audio.
Let's have a brief look at the main features
of MartinLogan Foundation C1 and Polk R400 first before getting into our more
detailed comparison.
| Key Specs | MartinLogan Foundation C1 | Polk R400 |
|---|
| Brand | MartinLogan
United States · founded 1982 | Polk Audio
United States · founded 1972 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Folded Motion Ribbon | 1" Pinnacle Ring Radiator |
|---|
| Woofer | 2 x 5-1/2" Aluminum | 2 x 6.5" Polypropylene Turbine Cone |
|---|
| Frequency response | 53-23k Hz | 48-39K Hz |
|---|
| Sensitivity | 91 dB | 89 dB |
|---|
| Impedance | 4 ohms | 8 ohms |
|---|
| Power range | up to 150 watts | 20-200 watts |
|---|
| Weight | 8.18kg / 18lbs | 14.91kg / 32.8lbs |
|---|
| Dimensions (H x W x D) | 7-5/8" x 20" x 10"
194.0 x 508.0 x 254.0mm | 7-13/16" x 24-5/16" x 14-5/8"
199.0 x 618.0 x 372.0mm |
|---|
What size room are the MartinLogan Foundation C1 and Polk R400 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* |
MartinLogan Foundation C1 |
Polk R400 |
| 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 Foundation C1 and R400 are 2-way speakers.
MartinLogan Foundation C1Polk R400
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
MartinLogan Foundation C1 |
Polk R400 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 5-1/2-inch
|
2 x 6.5-inch
|
Foundation C1 features a 1" Gen2 Obsidian Folded Motion Ribbon Tweeter and 2 x 5-1/2" Aluminum Woofer with a Crossover frequency at 2900 Hz - 3200 Hz. On the other hand, the R400 features a 1" Pinnacle Ring Radiator Tweeter and 2 x 6.5" Polypropylene Turbine Cone Woofer with a Crossover frequency at 2500Hz.
Frequency Response
Foundation C1 has a frequency range of 53-23k Hz whereas R400 has a frequency range of 48-39K Hz. With a minimum frequency of 48Hz, the R400 can go significantly deeper on the low side and provide stronger bass compared to the Foundation C1's min frequency of 53Hz.
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
Foundation C1 is a 4 ohms speaker compared to the R400 which has a nominal impedance of 8 ohms. Lower impedance speakers, especially the ones that are rated at 4 ohms may put more pressure on the amplifier unit especially when played at high volume levels, so make sure the amp you pair with the Foundation C1 can provide this impedance level.
These two speakers also have different sensitivity levels. Foundation C1 sensitivity is rated at 91 dB and the R400's is rated at 89 dB. This 2 dB difference makes the MartinLogan Foundation C1 a more sensitive speaker compared to Polk R400, 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.
R400 can handle a max power of 200 watts RMS, whereas Foundation C1 has a max power handling value of 150 watts RMS, 50 watts less than the R400.
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.
MartinLogan Foundation C1
Input Type and Bi-Amping / Bi-Wiring
Foundation C1 features Binding post type posts and R400 has a Binding post type posts. None of these speakers feature bi-amping/bi-wiring.
MartinLogan Foundation C1's Binding post terminals
Polk R400's Binding post terminals
Cabinet Type and Port Position
Both Foundation C1 and R400 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 R400 dual 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 MartinLogan Foundation C1's and Polk R400's external dimensions. MartinLogan Foundation C1 has external dimensions of 194.0 x 508.0 x 254.0mm (7-5/8inch x 20inch x 10inch) whereas Polk R400 has external dimensions of 199.0 x 618.0 x 372.0mm (7-13/16 x 24-5/16 x 14-5/8inch).
Polk R400 is clearly the larger of the two speakers. Its body is 110mm wider, 5mm taller and 118mm deeper than MartinLogan Foundation C1.
Below you can see the front view size comparison of MartinLogan Foundation C1 and Polk R400 in scale.
Comparison image of MartinLogan Foundation C1 and Polk R400 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 MartinLogan Foundation C1 is approximately 1290.3cm2 / 200.0inch2 and base area of the Polk R400 is approximately 2299.0cm2 / 356.3inch2. The Foundation C1 requires 44% less surface area than the R400 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 MartinLogan Foundation C1 weighs 8.18kg / 18lbs and the Polk R400 weighs 14.91kg / 32.8lbs. This makes the R400 82% heavier than the Foundation C1.
Here is a comparison of how Foundation C1 and R400's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
MartinLogan Foundation C1
What's in the Box of Polk R400?
Here are the items that come with the R400:
- Center-channel loudspeaker
- Grille
- Owners Manual
- Online Registration
 Sensitivity |
91 dB
vs
89 dB
|
Play louder with same amount of amplification power |
 Height |
194mm
vs
199mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1290cm2
vs
2299cm2
|
Takes less floor space |
 Price per pair* |
499USD
vs
649USD
|
costs less (*prices may change depending on the seller, location and time) |
 Max Input Power |
200 watts
vs
150 watts
|
Handle more power from your amplifier |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
 Woofer Size |
6.5 inches
vs
5-1/2 inches
|
Larger woofer |
|
Low Frequency Response |
48 Hz
vs
53 Hz
|
Generates deeper bass |
 High Frequency Response |
39k Hz
vs
23k Hz
|
Generates higher frequency |
| General |
MartinLogan Foundation C1 |
Polk Audio Reserve R400 |
| Brand |
MartinLogan |
Polk Audio |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
up to 150 watts |
20-200 watts |
| Sensitivity |
91 dB |
89 dB |
| Impedance |
4 ohms |
8 ohms |
| Impedance |
n/a |
4.1 ohms |
| Frequency Response |
53-23k Hz |
48-39K Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5-1/2" |
6.5" |
| Woofer Composition |
Aluminum |
Polypropylene Turbine Cone |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Folded Motion Ribbon |
Pinnacle Ring Radiator |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2900 Hz - 3200 Hz |
2500Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
194.0mm (7.6") |
199.0mm (7.8") |
| Width |
508.0mm (20") |
618.0mm (24.3") |
| Depth |
254.0mm (10") |
372.0mm (14.6") |
| Weight |
8.18kg (18lbs) |
14.91kg (32.8lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Available Colors |
Walnut,Black,Satin White |
Black, Walnut |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
No |
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 | B | Polk R400 digs deeper - 48Hz against 53Hz. A subwoofer would even that out. |
| Amplifier needs | A | MartinLogan Foundation C1 is more sensitive (91dB vs 89dB), so it goes louder on the same amplifier. |
| Amplifier match | B | Polk R400 is the easier load at 8 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Headroom | B | Polk R400 takes more power (200W vs 150W) - more in hand in a big room. |
| Size | depends | MartinLogan Foundation C1 is easier to place; Polk R400 is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | Neither adds bi-amping, a sub output or height drivers. Polk R400 sits in a wider range (10 models), so a matched surround system is easier later. |
| Price | A | MartinLogan Foundation C1 is cheaper - $499 against $649, about 23% less. |
A MartinLogan Foundation C1 B Polk R400
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?
The usual trade-off: Polk R400 measures better, MartinLogan Foundation C1 costs about about 30% more% less. Whether that gap is worth the money is the call only you can make - and in a normal room it is often smaller than the numbers suggest. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 53Hz anyway, which makes the cheaper MartinLogan Foundation C1 much easier to justify. In a large or open-plan room, Polk R400 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, MartinLogan Foundation C1 is the easier speaker to get right.
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.