In this review, we will be comparing Heresy IV and AK6, two Passive Floor-standing speakers by Klipsch.
Let's have a brief look at the main features
of Klipsch Heresy IV and Klipsch Klipschorn AK6 first before getting into our more
detailed comparison.
| Key Specs | Klipsch Heresy IV | Klipsch Klipschorn AK6 |
|---|
| Design | 3-way | 3-way |
|---|
| Tweeter | 1" horn-loaded | 1" Tractrix horn |
|---|
| Midrange | 1.75" | 2" |
|---|
| Woofer | 12" Fiber-composite | 15" fiber-composite with a trihedral exponential folded horn |
|---|
| Frequency response | 48-20k Hz | 33-20k Hz |
|---|
| Sensitivity | 99 dB | 105 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | up to 100 watts | up to 100 watts |
|---|
| Weight | 20.45kg / 45lbs | 100.00kg / 220lbs |
|---|
| Dimensions (H x W x D) | 24-13/16" x 15-1/2" x 13-1/4"
631.0 x 394.0 x 337.0mm | 53" x 31-1/4" x 28-1/4"
1347.0 x 794.0 x 718.0mm |
|---|
Heresy IV and AK6 are members of Klipsch's Heritage series of speakers. Below you can find the loudspeakers from this series.
Klipsch Heritage Series
History
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
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Drivers
Both Heresy IV and AK6 are 3-way speakers.
Klipsch Heresy IVKlipsch Klipschorn AK6
TweeterMidrangeWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Klipsch Heresy IV |
Klipsch Klipschorn AK6 |
|
Driver Setup
|
3-way
|
3-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
1 x 1.75-inch |
1 x 2-inch |
|
Woofer
|
1 x 12-inch
|
1 x 15-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 AK6 features a 1" polyimide diaphragm compression Tractrix horn Tweeter, a 2" Midrange and 1 x 15" fiber-composite with a trihedral exponential folded horn Woofer.
Frequency Response
Heresy IV has a frequency range of 48-20k Hz whereas AK6 has a frequency range of 33-20k Hz. With a minimum frequency of 33Hz, the AK6 can go significantly deeper on the low side and provide stronger bass compared to the Heresy IV's min frequency of 48Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Floor-standing class in our database.
Low Frequency
Floor-standing 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
Heresy IV and AK6 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 AK6's is at 105 dB. This 6 dB difference makes the Klipsch Klipschorn AK6 a more sensitive speaker compared to Klipsch Heresy IV, hence will play louder with the same amount of watts.
Sensitivity
Floor-standing 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.
Heresy IV and AK6 have the same power range of up to 100 watts.
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
Both Heresy IV and AK6 features dual binding post speaker terminals for bi-amping or bi-wiring.
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 Klipsch Heresy IV's and Klipsch Klipschorn AK6'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 Klipsch Klipschorn AK6 has external dimensions of 1347.0 x 794.0 x 718.0mm (53 x 31-1/4 x 28-1/4inch).
Klipsch Klipschorn AK6 is clearly the larger of the two speakers. Its body is 400mm wider, 716mm taller and 381mm deeper than Klipsch Heresy IV.
Below you can see the front view size comparison of Klipsch Heresy IV and Klipsch Klipschorn AK6 in scale.
Comparison image of Klipsch Heresy IV and Klipsch Klipschorn AK6 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 Klipsch Klipschorn AK6 is approximately 5700.9cm2 / 883.6inch2. The Heresy IV requires 77% less surface area than the AK6 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 Klipsch Heresy IV weighs 20.45kg / 45lbs and the Klipsch Klipschorn AK6 weighs 100.00kg / 220lbs. This makes the AK6 389% heavier than the Heresy IV.
Here is a comparison of how Heresy IV and AK6's weights compare with the average, max and min weights in Passive Floor-standing class.
Weight
All Floor-standing Speakers
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 Klipsch Klipschorn AK6?
Here are the items that come with the AK6:
- 2 Loudspeaker cabinets
- 2 Subwoofer cabinets
- 2 Grilles
- Owners Manual
- Congratulations letter
- Klipsch brochure
 Height |
631mm
vs
1347mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1327cm2
vs
5700cm2
|
Takes less floor space |
 Price per pair* |
3198USD
vs
16498USD
|
costs less (*prices may change depending on the seller, location and time) |
 Sensitivity |
105 dB
vs
99 dB
|
Play louder with same amount of amplification power |
 Woofer Size |
15 inches
vs
12 inches
|
Larger woofer |
|
Low Frequency Response |
33 Hz
vs
48 Hz
|
Generates deeper bass |
| General |
Klipsch Heritage Heresy IV |
Klipsch Heritage Klipschorn AK6 |
| Brand |
Klipsch |
Klipsch |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
up to 100 watts |
up to 100 watts |
| Sensitivity |
99 dB |
105 dB |
| Impedance |
8 ohms |
8 ohms |
| Frequency Response |
48-20k Hz |
33-20k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
15" |
| Woofer Composition |
Fiber-composite |
fiber-composite with a trihedral exponential folded horn |
| Woofer Surround Material |
Treated cloth |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
horn-loaded |
Tractrix horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
1.75" |
2" |
Physical Specs |
|
|
| Height |
631.0mm (24.8") |
1347.0mm (53") |
| Width |
394.0mm (15.5") |
794.0mm (31.3") |
| Depth |
337.0mm (13.3") |
718.0mm (28.3") |
| Weight |
20.45kg (45lbs) |
100.00kg (220lbs) |
| Enclosure |
Bass Reflex |
Acoustic Suspension |
| Finish |
MDF/Wood veneer |
MDF/Wood veneer |
| Available Colors |
Black |
American Walnut, Black Ash, Natural Cherry |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
Yes |
Yes |
Other |
|
|
| Parts Warranty |
10 Years |
10 Years |
| Labor Warranty |
10 Years |
10 Years |
Siblings in Klipsch's Heritage series, so they share a family sound. It comes down to size, output and price.
| Area | Better | Why |
|---|
| Bass |
B |
Klipsch Klipschorn AK6 digs deeper - 33Hz against 48Hz. |
| Amplifier needs |
B |
Klipsch Klipschorn AK6 is more sensitive (105dB vs 99dB), so it goes louder on the same amplifier. |
| Headroom |
evenly matched |
Similar power handling (100W vs 100W). |
| Size |
depends |
Klipsch Heresy IV is easier to place; Klipsch Klipschorn AK6 is bigger, which usually goes with fuller bass. Your room decides. |
| Cabinet |
depends |
Ported vs Sealed. Sealed is tighter and happier near a wall; ported digs lower but wants space behind it. |
| Expandability |
depends |
Klipsch Heresy IV: bi-amping; Klipsch Klipschorn AK6: bi-amping. |
| Price |
A |
Klipsch Heresy IV is cheaper - $3,198 against $16,498, about 81% less; arguably a different class. |
A Klipsch Heresy IV
B Klipsch Klipschorn AK6
depends neither is better in the abstract - it turns on your room, placement 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: Klipsch Klipschorn AK6 measures better, Klipsch Heresy IV costs about 81% 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 48Hz anyway, which makes the cheaper Klipsch Heresy IV much easier to justify. In a large or open-plan room, Klipsch Klipschorn AK6 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Klipsch Heresy IV 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.