In this review, we will be comparing AE509 and Opticon 8 MK2, two Passive Floor-standing speakers from Acoustic Energy and DALI.
Let's have a brief look at the main features
of AE509 and DALI Opticon 8 II first before getting into our more
detailed comparison.
| Key Specs | AE509 | DALI Opticon 8 II |
|---|
| Brand | Acoustic Energy
United Kingdom · founded 1987 | DALI
Denmark · founded 1983 |
|---|
| Design | 2-way | 3-way |
|---|
| Tweeter | 1" dome with waveguide | 17 x 45 mm ribbon + 1.125" Soft-dome + ribbon Hybrid |
|---|
| Midrange | — | 6.5" |
|---|
| Woofer | 2 x 5" carbon fibre cone | 2 x 8" Wood Fiber |
|---|
| Frequency response | 32Hz - 28kHz | 38-30k Hz |
|---|
| Sensitivity | 89 dB | 88 dB |
|---|
| Impedance | 6 ohms | 4 ohms |
|---|
| Power range | up to 175 watts | 40-300 watts |
|---|
| Weight | 22.00kg / 48.4lbs | 37.10kg / 81.6lbs |
|---|
| Dimensions (H x W x D) | 39.4" x 7.3" x 10.6"
1000.0 x 185.0 x 270.0mm | 45-1/4" x 9-1/2" x 18-1/16"
1150.0 x 245.0 x 459.0mm |
|---|
What size room are the AE509 and DALI Opticon 8 II 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* |
AE509 |
DALI Opticon 8 II |
| Near-field |
Bad |
Bad |
| Small Room |
Poor |
Poor |
| Mid-size Room |
Good |
Average |
| Large Room |
Good |
Good |
| Very Large Room |
Poor |
Average |
(* 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
One of the fundamental differences between these two speakers is that AE509 is a 2-way design whereas the Opticon 8 MK2 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.
AE509DALI Opticon 8 II
TweeterMidrangeWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
AE509 |
DALI Opticon 8 II |
|
Driver Setup
|
2-way
|
3-way
|
|
Tweeter
|
1-inch
|
17 x 45 mm ribbon + 1.125-inch
|
|
Midrange
|
- |
1 x 6.5-inch |
|
Woofer
|
2 x 5-inch
|
2 x 8-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 Opticon 8 MK2 features a 17 x 45 mm ribbon + 1.125" Soft-dome + ribbon Hybrid Tweeter, a 6.5" Midrange and 2 x 8" Wood Fiber Woofer with a Crossover frequency at 380Hz, 2200Hz and 14,000Hz.
Frequency Response
AE509 has a frequency range of 32Hz - 28kHz whereas Opticon 8 MK2 has a frequency range of 38-30k Hz. With a minimum frequency of 32Hz, the AE509 can go significantly deeper on the low side and provide stronger bass compared to the Opticon 8 MK2's min frequency of 38Hz.
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 Opticon 8 MK2 which has a nominal impedance of 4 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 Opticon 8 MK2 can provide this impedance level.
These two speakers also have different sensitivity levels. AE509 sensitivity is rated at 89 dB and the Opticon 8 MK2's is rated at 88 dB. This 1 dB difference makes the AE509 a more sensitive speaker compared to DALI Opticon 8 II, 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.
Opticon 8 MK2 can handle a max power of 300 watts RMS, whereas AE509 has a max power handling value of 175 watts RMS, 125 watts less than the Opticon 8 MK2.
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.
Cabinet Type and Port Position
Both AE509 and Opticon 8 MK2 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.
DALI Opticon 8 II 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 AE509's and DALI Opticon 8 II'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 DALI Opticon 8 II has external dimensions of 1150.0 x 245.0 x 459.0mm (45-1/4 x 9-1/2 x 18-1/16inch).
DALI Opticon 8 II is clearly the larger of the two speakers. Its body is 60mm wider, 150mm taller and 189mm 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 DALI Opticon 8 II is approximately 1124.6cm2 / 174.3inch2. The AE509 requires 56% less surface area than the Opticon 8 MK2 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 DALI Opticon 8 II weighs 37.10kg / 81.6lbs. This makes the Opticon 8 MK2 69% heavier than the AE509.
Here is a comparison of how AE509 and Opticon 8 MK2'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 DALI Opticon 8 II?
Here are the items that come with the Opticon 8 MK2:
- Floorstanding loudspeaker
- Grille
- 2 Binding post jumpers (pre-installed)
- 4 Outrigger feet
- 4 Spikes (with lock nuts)
- 4 Rubber pads
- 4 Screws
- Hex-key
- Wrench
- Quick Start Guide
- Congratulations Card
 Sensitivity |
89 dB
vs
88 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
6 ohms
vs
4 ohms
|
Less selective with amplifiers |
 Low Frequency Response |
32 Hz
vs
38 Hz
|
Generates deeper bass |
 Height |
1000mm
vs
1150mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
499cm2
vs
1124cm2
|
Takes less floor space |
 Price per pair* |
3499USD
vs
4200USD
|
costs less (*prices may change depending on the seller, location and time) |
 Max Input Power |
300 watts
vs
175 watts
|
Handle more power from your amplifier |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
|
Woofer Size |
8 inches
vs
5 inches
|
Larger woofer |
 High Frequency Response |
30k Hz
vs
28k Hz
|
Generates higher frequency |
| General |
Acoustic Energy AE509 |
DALI Opticon 8 MK2 |
| Brand |
Acoustic Energy |
DALI |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
up to 175 watts |
40-300 watts |
| Sensitivity |
89 dB |
88 dB |
| Impedance |
6 ohms |
4 ohms |
| Frequency Response |
32Hz - 28kHz |
38-30k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5" |
8" |
| Woofer Composition |
carbon fibre cone |
Wood Fiber |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
1" |
17 x 45 mm ribbon + 1.125" |
| Tweeter Type |
dome with waveguide |
Soft-dome + ribbon Hybrid |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
6.5" |
| Crossover Frequency |
2800Hz |
380Hz, 2200Hz and 14,000Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
1000.0mm (39.4") |
1150.0mm (45.3") |
| Width |
185.0mm (7.3") |
245.0mm (9.6") |
| Depth |
270.0mm (10.6") |
459.0mm (18.1") |
| Weight |
22.00kg (48.4lbs) |
37.10kg (81.6lbs) |
| 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 |
Satin Black, Tobacco Oak, Satin White |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
n/a |
Yes |
Other |
|
|
| Parts Warranty |
|
5 Years |
| Labor Warranty |
|
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 | A | AE509 digs deeper - 32Hz against 38Hz. A subwoofer would even that out. |
| Amplifier needs | evenly matched | Similar sensitivity (89dB vs 88dB) - both want much the same power. |
| Amplifier match | A | AE509 is the easier load at 6 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Headroom | B | DALI Opticon 8 II takes more power (300W vs 175W) - more in hand in a big room. |
| Size | depends | AE509 is easier to place; DALI Opticon 8 II is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | B | DALI Opticon 8 II: bi-amping. DALI Opticon 8 II sits in a wider range (6 models), so a matched surround system is easier later. |
| Price | A | AE509 is cheaper - $3,499 against $4,200, about 17% less. |
A AE509 B DALI Opticon 8 II
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?
Neither runs away with it - they trade advantages. Let the "depends" rows and your own room settle it. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 38Hz anyway, so judge these on the other rows instead. Match it to your room: we rate AE509 the better fit for a mid-size room, and DALI Opticon 8 II for a very large room.
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.