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Klipsch Heresy IV vs B&W 603 Comparison

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Klipsch Heresy IV

Passive Floor-standing | 48-20k Hz

Klipsch Heritage Heresy IV
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B&W 603

Passive Floor-standing | 48-28k Hz

Bowers & Wilkins 603
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Klipsch Heresy IV Klipsch Heresy IV
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B&W 603 B&W 603
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Klipsch Heresy IV
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B&W 603
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Klipsch Heresy IV vs B&W 603 Speaker Comparison

In this review, we will be comparing Heresy IV and BW 603, two Passive Floor-standing speakers from Klipsch and Bowers Wilkins.

Let's have a brief look at the main features of Klipsch Heresy IV and B&W 603 first before getting into our more detailed comparison.

Klipsch Heresy IV Key Specs

  • 3-way Design
  • 1" horn-loaded Tweeter
  • 1.75" Midrange
  • 12" Fiber-composite Woofer
  • 48-20k Hz Frequency Response
  • 99 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:up to 100watts
  • Weight:20.45kg
  • Dimensions (H x W x D): 631.0" x 15-1/2" x 13-1/4"( 631.0 x 394.0 x 337.0mm )

B&W 603 Key Specs

  • 3-way Design
  • 1" Tweeter
  • 6" Midrange
  • 2 x 6.5" Paper Woofer
  • 6" Midrange
  • 48-28k Hz Frequency Response
  • 88.5 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:30-200watts
  • Weight:24.14kg
  • Dimensions (H x W x D): 985.0" x 7.4" x 13.3"( 985.0 x 190.0 x 340.0mm )

In the following sections, we will get into more detail in order to better understand how the Klipsch Heresy IV and B&W 603 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

Both Heresy IV and BW 603 are 3-way speakers.

Driver Klipsch Heresy IV B&W 603
Driver Setup 3-way 3-way
Tweeter 1-inch 1-inch
Midrange 1 x 1.75-inch 1 x 6-inch
Woofer 1 x 12-inch 2 x 6.5-inch

Heresy IV features a 1" titanium-diaphragm compression horn-loaded Tweeter , a 1.75" Midrange and 1 x 12" Fiber-composite Woofer . On the other hand, the BW 603 features a 1" Tweeter , a 6" Midrange and 2 x 6.5" Paper Woofer .

Frequency Response

Heresy IV has a frequency range of 48-20k Hz whereas BW 603 has a frequency range of 48-28k Hz.

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 Floor-standing class in our database.

Low Frequency

Floor-standing Speakers

Heresy IV
BW 603
Min
Average
Max
High Frequency

Floor-standing Speakers

Klipsch Heresy IV
B&W 603
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

Heresy IV and BW 603 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Heresy IV sensitivity is rated at 99 dB and the BW 603's is at 88.5 dB. This 10 dB difference makes the Klipsch Heresy IV a more sensitive speaker compared to B&W 603, hence will play louder with the same amount of watts.

Sensitivity

Floor-standing Speakers

Heresy IV
BW 603
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.

Heresy IV can handle a max power of 200 watts RMS from the amp the whereas Heresy IV has a max power handling value of 100 watts RMS , 100 watts less than the BW 603.

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

Both Heresy IV and BW 603 features dual binding post speaker terminals for bi-amping or 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 Klipsch Heresy IV's and B&W 603's external dimensions. Klipsch Heresy IV has external dimensions of 631.0 x 394.0 x 337.0mm ( 24-13/16 x 15-1/2 x 13-1/4inch) whereas B&W 603 has external dimensions of 985.0 x 190.0 x 340.0mm ( 38.7 x 7.4 x 13.3inch) .

Klipsch Heresy IV is 354mm shorter and 3mm less deeper than B&W 603 but it is also 204mm wider.

Below you can see the front view size comparison of Klipsch Heresy IV and B&W 603 in scale.

Klipsch Heresy IV vs B&W 603 Size Comparison - Front View
Comparison image of Klipsch Heresy IV and B&W 603 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 Klipsch Heresy IV is approximately 1327.8cm2 / 205.8inch2 and base area of the B&W 603 is approximately 646.0cm2 / 100.1inch2. The Heresy IV requires 106% more surface area than the BW 603 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 Klipsch Heresy IV weighs 20.45kg / 45lbs and the B&W 603 weighs 24.14kg / 53.1lbs. This makes the BW 603 18% heavier than the Heresy IV.

Here is a comparison of how Heresy IV and BW 603's weights compare with the average, max and min weights in Passive Floor-standing class.

Weight
All Floor-standing Speakers
Klipsch Heresy IV
B&W 603
Min
Average
Max

What's in the Box of Klipsch Heresy IV?

Here are the items that are included inside the box of Heresy IV:
  • 2 Floor-standing loudspeakers
  • 2 Detachable grilles (installed)
  • 2 Base risers (installed)
  • 8 Self-adhesive rubber feet
  • 4 Jumper-straps (installed)
  • Owners Manual
  • Congratulations letter
  • Klipsch brochure
  • What's in the Box of B&W 603?

    Here are the items that come with the BW 603:
  • Floorstanding loudspeaker
  • Grille
  • Plinith (base)
  • 2 Jumper-straps (pre-installed)
  • 4 Rubber feet
  • 4 Spike feet
  • 4 Hex-nuts
  • 4 Screws
  • 4 Washers
  • 4 Lock-washers
  • Two-piece foam port plug
  • Hex-key
  • Manual
  • Bowers & Wilkins brochure
  • Warranty Information

  • Reasons to choose Klipsch Heritage Heresy IV over Bowers & Wilkins 603
    Sensitivity 99 dB vs 89 dB Play louder with same amount of amplification power
    Woofer Size 12 inches vs 6.5 inches Larger woofer
    Height 631mm vs 985mm Easier to fit in smaller spaces

    Reasons to choose Bowers & Wilkins 603 over Klipsch Heritage Heresy IV

    Max Input Power 200 watts vs 100 watts Handle more power from your amplifier
    Number of Woofers 2 vs 1 More woofers
    High Frequency Response 28k Hz vs 20k Hz Generates higher frequency
    Base Surface Area 646cm2 vs 1327cm2 Takes less floor space
    Klipsch Heresy IV vs B&W 603 Specs Table
    Detailed comparison of specifications
    General Klipsch Heritage Heresy IV Bowers & Wilkins 603
    Brand Klipsch Bowers Wilkins
    Speaker Type Floor-standing speaker Floor-standing speaker
    Power Range up to 100 watts 30-200 watts
    Sensitivity 99 dB 88.5 dB
    Impedance 8 ohms 8 ohms
    Frequency Response 48-20k Hz 48-28k Hz
    Drivers
    Woofer Quantity 1 2
    Woofer Size 12" 6.5"
    Woofer Composition Fiber-composite Paper
    Woofer Surround Material Treated cloth Rubber
    Tweeter Size 1" 1"
    Tweeter Type horn-loaded n/a
    Aimable Tweeter No No
    Midrange Driver 1.75" 6"
    Firing Direction n/a rear
    Physical Specs
    Height 631.0mm (24.8") 985.0mm (38.8")
    Width 394.0mm (15.5") 190.0mm (7.5")
    Depth 337.0mm (13.3") 340.0mm (13.4")
    Weight 20.45kg (45lbs) 24.14kg (53.1lbs)
    Enclosure Bass Reflex Bass Reflex
    Finish MDF/Wood veneer MDF/Vinyl
    Available Colors Black Black, White, Oak
    Grille Yes Yes
    Moisture Resistancy No No
    Connections
    Biamp Inputs Yes Yes
    Other
    Parts Warranty 10 Years 5 Years
    Labor Warranty 10 Years 5 Years

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