In this review, we will be comparing AE509 and Concord, two Passive Floor-standing speakers from Acoustic Energy and KLH.
Let's have a brief look at the main features
of AE509 and KLH Concord first before getting into our more
detailed comparison.
| Key Specs | AE509 | KLH Concord |
|---|
| Brand | Acoustic Energy
United Kingdom · founded 1987 | KLH
United States · founded 1957 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" dome with waveguide | 1" |
|---|
| Woofer | 2 x 5" carbon fibre cone | 2 x 6.5" Kevlar |
|---|
| Frequency response | 32Hz - 28kHz | 28-23k Hz |
|---|
| Sensitivity | 89 dB | 94 dB |
|---|
| Impedance | 6 ohms | 8 ohms |
|---|
| Power range | up to 175 watts | up to 225 watts |
|---|
| Weight | 22.00kg / 48.4lbs | 20.45kg / 45lbs |
|---|
| Dimensions (H x W x D) | 39.4" x 7.3" x 10.6"
1000.0 x 185.0 x 270.0mm | 40-3/8" x 8-5/16" x 14-15/16"
1026.0 x 212.0 x 380.0mm |
|---|
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both AE509 and Concord are 2-way speakers.
AE509KLH Concord
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
AE509 |
KLH Concord |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 5-inch
|
2 x 6.5-inch
|
AE509 features a 1" carbon fibre dome with waveguide Tweeter and 2 x 5" carbon fibre cone Woofer with a Crossover frequency at 2800Hz. On the other hand, the Concord features a 1" anodized aluminum Tweeter and 2 x 6.5" Kevlar Woofer.
Frequency Response
AE509 has a frequency range of 32Hz - 28kHz whereas Concord has a frequency range of 28-23k Hz. With a minimum frequency of 28Hz, the Concord can go slightly deeper then the AE509's min frequency of 32Hz.
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
AE509 is a 6 ohms speaker compared to the Concord which has a nominal impedance of 8 ohms.
These two speakers also have different sensitivity levels. AE509 sensitivity is rated at 89 dB and the Concord's is rated at 94 dB. This 5 dB difference makes the KLH Concord a more sensitive speaker compared to AE509, 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.
Concord can handle a max power of 225 watts RMS, whereas AE509 has a max power handling value of 175 watts RMS, 50 watts less than the Concord.
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.
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 AE509's and KLH Concord's external dimensions. AE509 has external dimensions of 1000.0 x 185.0 x 270.0mm (39.4 x 7.3 x 10.6inch) whereas KLH Concord has external dimensions of 1026.0 x 212.0 x 380.0mm (40-3/8 x 8-5/16 x 14-15/16inch).
KLH Concord is clearly the larger of the two speakers. Its body is 27mm wider, 26mm taller and 110mm deeper than AE509.
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 AE509 is approximately 499.5cm2 / 77.4inch2 and base area of the KLH Concord is approximately 805.6cm2 / 124.9inch2. The AE509 requires 38% less surface area than the Concord 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 AE509 weighs 22.00kg / 48.4lbs and the KLH Concord weighs 20.45kg / 45lbs. This makes the AE509 8% heavier than the Concord.
Here is a comparison of how AE509 and Concord'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 KLH Concord?
Here are the items that come with the Concord:
- Floorstanding loudspeaker
- Grille
- 4 Spike feet (w/ locking nut attached)
- 4 Protective discs
- 4 Rubber feet
- Port plug
- Manual
- ATTENTION! note
 High Frequency Response |
28k Hz
vs
23k Hz
|
Generates higher frequency |
 Height |
1000mm
vs
1026mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
499cm2
vs
805cm2
|
Takes less floor space |
 Max Input Power |
225 watts
vs
175 watts
|
Handle more power from your amplifier |
 Sensitivity |
94 dB
vs
89 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
6 ohms
|
Less selective with amplifiers |
 Woofer Size |
6.5 inches
vs
5 inches
|
Larger woofer |
|
Low Frequency Response |
28 Hz
vs
32 Hz
|
Generates deeper bass |
 Price per pair* |
1000USD
vs
3499USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Acoustic Energy AE509 |
KLH Concord |
| Brand |
Acoustic Energy |
KLH |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
up to 175 watts |
up to 225 watts |
| Sensitivity |
89 dB |
94 dB |
| Impedance |
6 ohms |
8 ohms |
| Frequency Response |
32Hz - 28kHz |
28-23k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5" |
6.5" |
| Woofer Composition |
carbon fibre cone |
Kevlar |
| Woofer Surround Material |
n/a |
Butyl Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
dome with waveguide |
n/a |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2800Hz |
n/a |
| Firing Direction |
rear |
n/a |
Physical Specs |
|
|
| Height |
1000.0mm (39.4") |
1026.0mm (40.4") |
| Width |
185.0mm (7.3") |
212.0mm (8.3") |
| Depth |
270.0mm (10.6") |
380.0mm (15") |
| Weight |
22.00kg (48.4lbs) |
20.45kg (45lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
Resonance Suppression Composite (RSC) |
MDF/Wood-grain vinyl |
| Available Colors |
Piano Gloss Black, Piano Gloss White, American Walnut wood veneer |
Black |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
n/a |
No |
Other |
|
|
| Parts Warranty |
|
10 Years |
| Labor Warranty |
|
10 Years |
These sit in different price classes - AE509 costs roughly 3.5x what KLH Concord does. Expect it to lead on paper; the question is whether the gap is audible enough in your room to be worth it.
| Area | Better | Why |
|---|
| Bass | B | KLH Concord digs deeper - 28Hz against 32Hz. A subwoofer would even that out. |
| Amplifier needs | B | KLH Concord is more sensitive (94dB vs 89dB), so it goes louder on the same amplifier. |
| Amplifier match | B | KLH Concord is the easier load at 8 ohms. |
| Headroom | B | KLH Concord takes more power (225W vs 175W) - more in hand in a big room. |
| Size | depends | AE509 is easier to place; KLH Concord is bigger, which usually goes with fuller bass. Your room decides. |
| Price | B | KLH Concord is cheaper - $1,000 against $3,499, about 71% less; arguably a different class. |
A AE509 B KLH Concord
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?
KLH Concord is the easier recommendation: it leads on most of the measured areas and costs less. Take AE509 if its size, looks or fit in your room suit you better. In a large or open-plan room, KLH Concord has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, AE509 is the easier speaker to get right. If your amplifier is modest, vintage or valve-based, KLH Concord is the safer partner - the other will want more current or more watts to sound its best.
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.