In this review, we will be comparing ZX-4 and Concord, two Passive Floor-standing speakers from Mission and KLH.
Let's have a brief look at the main features
of Mission ZX-4 and KLH Concord first before getting into our more
detailed comparison.
| Key Specs | Mission ZX-4 | KLH Concord |
|---|
| Brand | Mission
United Kingdom · founded 1977 | KLH
United States · founded 1957 |
|---|
| Design | 3-way | 2-way |
|---|
| Tweeter | 1.5" Ring Dome | 1" |
|---|
| Midrange | 5.25" | — |
|---|
| Woofer | 2 x 5.25" Aluminium | 2 x 6.5" Kevlar |
|---|
| Frequency response | 40-24k Hz | 28-23k Hz |
|---|
| Sensitivity | 90 dB | 94 dB |
|---|
| Impedance | 4 ohms | 8 ohms |
|---|
| Power range | 25-150 watts | up to 225 watts |
|---|
| Weight | 24.60kg / 54.1lbs | 20.45kg / 45lbs |
|---|
| Dimensions (H x W x D) | 42-5/16" x 9-7/16" x 14-1/4"
1075.0 x 240.0 x 362.0mm | 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
One of the fundamental differences between these two speakers is that ZX-4 is a 3-way design whereas the Concord is a 2-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.
Mission ZX-4KLH Concord
TweeterMidrangeWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Mission ZX-4 |
KLH Concord |
|
Driver Setup
|
3-way
|
2-way
|
|
Tweeter
|
1.5-inch
|
1-inch
|
|
Midrange
|
1 x 5.25-inch |
- |
|
Woofer
|
2 x 5.25-inch
|
2 x 6.5-inch
|
ZX-4 features a 1.5" Silk Ring Dome Tweeter, a 5.25" Midrange and 2 x 5.25" Aluminium Woofer with a Crossover frequency at 530Hz,2.7kHz. On the other hand, the Concord features a 1" anodized aluminum Tweeter and 2 x 6.5" Kevlar Woofer.
Frequency Response
ZX-4 has a frequency range of 40-24k Hz whereas Concord has a frequency range of 28-23k Hz. With a minimum frequency of 28Hz, the Concord can go significantly deeper on the low side and provide stronger bass compared to the ZX-4's min frequency of 40Hz.
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
ZX-4 is a 4 ohms speaker compared to the Concord 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 ZX-4 can provide this impedance level.
These two speakers also have different sensitivity levels. ZX-4 sensitivity is rated at 90 dB and the Concord's is rated at 94 dB. This 4 dB difference makes the KLH Concord a more sensitive speaker compared to Mission ZX-4, 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 ZX-4 has a max power handling value of 150 watts RMS, 75 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.
Input Type and Bi-Amping / Bi-Wiring
ZX-4 features Binding post posts which make bi-amping or bi-wiring possible. Concord has a 5-Way post which doesn't feature bi-amping/bi-wiring.
KLH Concord's 5-Way post terminals
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 Mission ZX-4's and KLH Concord's external dimensions. Mission ZX-4 has external dimensions of 1075.0 x 240.0 x 362.0mm (42-5/16 x 9-7/16 x 14-1/4inch) 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 28mm narrower and 49mm shorter than Mission ZX-4 but it is also 18mm deeper.
Size, drawn to scale
Both speakers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same surface and pushed back to the same wall, so the deeper one visibly sticks out further.
Near-identical footprints. KLH Concord is 18mm deeper, so it stands that much further out from the wall. Mission ZX-4 is 49mm taller.
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 Mission ZX-4 is approximately 868.8cm2 / 134.7inch2 and base area of the KLH Concord is approximately 805.6cm2 / 124.9inch2. The ZX-4 requires 8% more surface area than the Concord 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 Mission ZX-4 weighs 24.60kg / 54.1lbs and the KLH Concord weighs 20.45kg / 45lbs. This makes the ZX-4 20% heavier than the Concord.
Here is a comparison of how ZX-4 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
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
 High Frequency Response |
24k Hz
vs
23k Hz
|
Generates higher frequency |
 Bi-Amping and Bi-Wiring |
Yes
vs
No
|
Allows bi-amping and bi-wiring connections |
 Max Input Power |
225 watts
vs
150 watts
|
Handle more power from your amplifier |
 Sensitivity |
94 dB
vs
90 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
 Woofer Size |
6.5 inches
vs
5.25 inches
|
Larger woofer |
|
Low Frequency Response |
28 Hz
vs
40 Hz
|
Generates deeper bass |
 Height |
1026mm
vs
1075mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
805cm2
vs
868cm2
|
Takes less floor space |
 Price per pair* |
1000USD
vs
1799USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Mission ZX-4 |
KLH Concord |
| Brand |
Mission |
KLH |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
25-150 watts |
up to 225 watts |
| Sensitivity |
90 dB |
94 dB |
| Impedance |
4 ohms |
8 ohms |
| Impedance |
3.4 ohms |
n/a |
| Frequency Response |
40-24k Hz |
28-23k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5.25" |
6.5" |
| Woofer Composition |
Aluminium |
Kevlar |
| Woofer Surround Material |
n/a |
Butyl Rubber |
| Tweeter Size |
1.5" |
1" |
| Tweeter Type |
Ring Dome |
n/a |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
5.25" |
No |
| Crossover Frequency |
530Hz,2.7kHz |
n/a |
Physical Specs |
|
|
| Height |
1075.0mm (42.3") |
1026.0mm (40.4") |
| Width |
240.0mm (9.4") |
212.0mm (8.3") |
| Depth |
362.0mm (14.3") |
380.0mm (15") |
| Weight |
24.60kg (54.1lbs) |
20.45kg (45lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
n/a |
MDF/Wood-grain vinyl |
| Available Colors |
n/a |
Black |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
Yes |
No |
Other |
|
|
| Parts Warranty |
|
10 Years |
| Labor Warranty |
|
10 Years |
These sit in different price classes - Mission ZX-4 costs roughly 1.8x 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 40Hz. |
| Amplifier needs | B | KLH Concord is more sensitive (94dB vs 90dB), so it goes louder on the same amplifier. |
| Amplifier match | B | KLH Concord is the easier load at 8 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Headroom | B | KLH Concord takes more power (225W vs 150W) - more in hand in a big room. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | A | Mission ZX-4: bi-amping. |
| Price | B | KLH Concord is cheaper - $1,000 against $1,799, about 44% less; arguably a different class. |
A Mission ZX-4 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 Mission ZX-4 if its size, looks or fit in your room suit you better. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 40Hz anyway, so judge these on the other rows instead. 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.