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Buchardt S400 MKII vs KEF R3 Comparison

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Buchardt S400 MKII

Passive Bookshelf | 33-40k HZ

Buchardt S400 MKII
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KEF R3

Passive Bookshelf | 52-28k Hz

KEF R3
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Buchardt S400 MKII Buchardt S400 MKII
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KEF R3 KEF R3
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Buchardt S400 MKII
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KEF R3
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Buchardt S400 MKII vs KEF R3 Speaker Comparison

In this review, we will be comparing S400 MKII and R3, two Passive Bookshelf speakers from Buchardt and KEF.

Let's have a brief look at the main features of Buchardt S400 MKII and KEF R3 first before getting into our more detailed comparison.

Buchardt S400 MKII Key Specs

  • 2-way Design
  • 0.74" aluminum waveguide Tweeter
  • 6" paper Woofer
  • 33-40k HZ Frequency Response
  • 88 dB Sensitivity
  • Impedance: 4ohms
  • Power Range:40-200watts
  • Weight:7.50kg
  • Dimensions (H x W x D): 365.0" x 7" x 11"( 365.0 x 180.0 x 280.0mm )

KEF R3 Key Specs

  • 3-way Design
  • 1" Dome Tweeter
  • 5" Midrange
  • 6.5" Hybrid aluminum Woofer
  • 5" Midrange
  • 52-28k Hz Frequency Response
  • 87 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:15-180watts
  • Weight:13.55kg
  • Dimensions (H x W x D): 423.0" x 7-13/16" x 13-1/4"( 423.0 x 199.0 x 337.0mm )

What size room are the Buchardt S400 MKII and KEF R3 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* Buchardt S400 MKII KEF R3
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.)

In the following sections, we will get into more detail in order to better understand how the Buchardt S400 MKII and KEF R3 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.


**This post contains affiliate links, and I will be compensated if you make a purchase after clicking through my links. As an Amazon Associate I earn from qualifying purchases.


Drivers

One of the fundamental differences between these two speakers is that S400 MKII is a 2-way design whereas the R3 is a 3-way speaker. 3-way designs utilize a midrange driver in addition to the tweeter and woofer on 2-way designs. Designing a crossover for a 3-way speaker is a complicated process and generally increases the overall cost of the speaker.

Driver Buchardt S400 MKII KEF R3
Driver Setup 2-way 3-way
Tweeter 0.74-inch 1-inch
Midrange - 1 x 5-inch
Woofer 1 x 6-inch 1 x 6.5-inch

S400 MKII features a 0.74" fine weave soft fabric textile aluminum waveguide Tweeter and 1 x 6" paper Woofer with a Crossover frequency at 1800Hz. On the other hand, the R3 features a 1" aluminum Dome Tweeter , a 5" Midrange and 1 x 6.5" Hybrid aluminum Woofer with a Crossover frequency at 400Hz and 2900Hz.

Frequency Response

S400 MKII has a frequency range of 33-40k HZ whereas R3 has a frequency range of 52-28k Hz. With a minimum frequency of 33Hz, the S400 MKII can go significantly deeper on the low side and provide stronger bass compared to the R3's min frequency of 52Hz.

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 Bookshelf class in our database.

Low Frequency

Bookshelf Speakers

S400 MKII
R3
Min
Average
Max
High Frequency

Bookshelf Speakers

Buchardt S400 MKII
KEF R3
Min
Average
Max

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

S400 MKII is a 4 ohms speaker compared to the R3 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 S400 MKII can provide this impedance level.

These two speakers also have different sensitivity levels. S400 MKII sensitivity is rated at 88 dB and the R3's is rated at 87 dB. This 1 dB difference makes the Buchardt S400 MKII a more sensitive speaker compared to KEF R3, hence will play louder with the same amount of watts.

Sensitivity

Bookshelf Speakers

S400 MKII
R3
Min
Average
Max

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.

S400 MKII can handle a max power of 200 watts RMS from the amp the whereas R3 has a max power handling value of 180 watts RMS, 20 watts less than the S400 MKII.

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.

KEF R3  Port
KEF R3 Port

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 Buchardt S400 MKII's and KEF R3's external dimensions. Buchardt S400 MKII has external dimensions of 365.0 x 180.0 x 280.0mm ( 14.4 x 7 x 11inch) whereas KEF R3 has external dimensions of 423.0 x 199.0 x 337.0mm ( 16-5/8 x 7-13/16 x 13-1/4inch) .

KEF R3 is clearly the larger of the two speakers. Its body is 19mm wider, 58mm taller and 57mm deeper than Buchardt S400 MKII.

Below you can see the front view size comparison of Buchardt S400 MKII and KEF R3 in scale.

Buchardt S400 MKII vs KEF R3 Size Comparison - Front View
Comparison image of Buchardt S400 MKII and KEF R3 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 Buchardt S400 MKII is approximately 504.0cm2 / 78.1inch2 and base area of the KEF R3 is approximately 670.6cm2 / 103.9inch2. The S400 MKII requires 25% less surface area than the R3 which gives it a small advantage on placement in tight spaces.

Here is an another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:

Buchardt S400 MKII vs KEF R3 Size Comparison on a Media Console
Size Comparison image of Buchardt S400 MKII and KEF R3 on a Media Console
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 Buchardt S400 MKII weighs 7.50kg / 16.5lbs and the KEF R3 weighs 13.55kg / 29.8lbs. This makes the R3 81% heavier than the S400 MKII.

Here is a comparison of how S400 MKII and R3's weights compare with the average, max and min weights in Passive Bookshelf class.

Weight
All Bookshelf Speakers
Buchardt S400 MKII
KEF R3
Min
Average
Max

What's in the Box of KEF R3?

Here are the items that come with the R3:
  • 2 Bookshelf loudspeakers
  • 2 Grilles
  • 2 Foam port plugs
  • 8 Self-adhesive rubber feet
  • User Manual
  • Warranty Information

  • Reasons to choose Buchardt S400 MKII over KEF R3
    Max Input Power 200 watts vs 180 watts Handle more power from your amplifier
    Sensitivity 88 dB vs 87 dB Play louder with same amount of amplification power
    Low Frequency Response 33 Hz vs 52 Hz Generates deeper bass
    High Frequency Response 40k Hz vs 28k Hz Generates higher frequency
    Passive Radiator one 5x8-inch vs None Increases the bass performance
    Height 365mm vs 423mm Easier to fit in smaller spaces
    Base Surface Area 504cm2 vs 670cm2 Takes less floor space

    Reasons to choose KEF R3 over Buchardt S400 MKII

    Driver Setup 3-way vs 2-way Have a dedicated mid-range driver
    Nominal Impedance 8 ohms vs 4 ohms Less selective with amplifiers
    Woofer Size 6.5 inches vs 6 inches Larger woofer
    Buchardt S400 MKII vs KEF R3 Specs Table
    Detailed comparison of specifications
    General Buchardt S400 MKII KEF R3
    Brand Buchardt KEF
    Speaker Type Bookshelf speakers Bookshelf speakers
    Power Range 40-200 watts 15-180 watts
    Sensitivity 88 dB 87 dB
    Impedance 4 ohms 8 ohms
    Impedance n/a 3.2 ohms
    Frequency Response 33-40k HZ 52-28k Hz
    Drivers
    Woofer Quantity 1 1
    Woofer Size 6" 6.5"
    Woofer Composition paper Hybrid aluminum
    Woofer Surround Material n/a Rubber
    Tweeter Size 0.74" 1"
    Tweeter Type aluminum waveguide Dome
    Aimable Tweeter No No
    Midrange Driver No 5"
    Crossover Frequency 1800Hz 400Hz and 2900Hz
    Firing Direction n/a rear
    Physical Specs
    Height 365.0mm (14.4") 423.0mm (16.7")
    Width 180.0mm (7.1") 199.0mm (7.8")
    Depth 280.0mm (11") 337.0mm (13.3")
    Weight 7.50kg (16.5lbs) 13.55kg (29.8lbs)
    Enclosure Passive Radiator Bass Reflex
    Finish n/a MDF/Lacquer
    Available Colors Black, White, Walnut, Rosewood, Light Oak Black Gloss, White Gloss, Walnut
    Mounting Bracket No No
    Grille Yes Yes
    Moisture Resistancy No No
    Connections
    Biamp Inputs n/a Yes
    Other
    Parts Warranty 10 years 5 Years
    Labor Warranty 10 years 5 Years

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