In this review, we will be comparing NS-555 and Concord, two Passive Floor-standing speakers from Yamaha and KLH.
Let's have a brief look at the main features
of Yamaha NS-555 and KLH Concord first before getting into our more
detailed comparison.
| Key Specs | Yamaha NS-555 | KLH Concord |
|---|
| Brand | Yamaha
Japan · founded 1887 | KLH
United States · founded 1957 |
|---|
| Design | 3-way | 2-way |
|---|
| Tweeter | 1" Aluminum dome with waveguide horn | 1" |
|---|
| Midrange | 5" | — |
|---|
| Woofer | 2 x 6.5" PMD cone | 2 x 6.5" Kevlar |
|---|
| Frequency response | 35-35k Hz | 28-23k Hz |
|---|
| Sensitivity | 88 dB | 94 dB |
|---|
| Impedance | 6 ohms | 8 ohms |
|---|
| Power range | 100-250 watts | up to 225 watts |
|---|
| Weight | 20.00kg / 44lbs | 20.45kg / 45lbs |
|---|
| Dimensions (H x W x D) | 38.5625" x 8.75" x 13.5625"
979.5 x 222.3 x 344.5mm | 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 NS-555 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.
Yamaha NS-555KLH 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 |
Yamaha NS-555 |
KLH Concord |
|
Driver Setup
|
3-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
1 x 5-inch |
- |
|
Woofer
|
2 x 6.5-inch
|
2 x 6.5-inch
|
NS-555 features a 1" Aluminum dome with waveguide horn Aluminum dome with waveguide horn Tweeter, a 5" Midrange and 2 x 6.5" PMD cone Woofer. On the other hand, the Concord features a 1" anodized aluminum Tweeter and 2 x 6.5" Kevlar Woofer.
Frequency Response
NS-555 has a frequency range of 35-35k 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 NS-555's min frequency of 35Hz.
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
NS-555 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. NS-555 sensitivity is rated at 88 dB and the Concord's is rated at 94 dB. This 6 dB difference makes the KLH Concord a more sensitive speaker compared to Yamaha NS-555, 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.
NS-555 can handle a max power of 250 watts RMS, whereas Concord has a max power handling value of 225 watts RMS, 25 watts less than the NS-555.
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
NS-555 features 5-Way post type posts and Concord has a 5-Way post type posts. None of these speakers 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 Yamaha NS-555's and KLH Concord's external dimensions. Yamaha NS-555 has external dimensions of 979.5 x 222.3 x 344.5mm (38.5625 x 8.75 x 13.5625inch) 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).
Yamaha NS-555 is 46.5mm shorter and 35.5mm less deeper than KLH Concord but it is also 10.3mm wider.
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 36mm deeper, so it stands that much further out from the wall. KLH Concord is 47mm 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 Yamaha NS-555 is approximately 765.8cm2 / 118.7inch2 and base area of the KLH Concord is approximately 805.6cm2 / 124.9inch2. The NS-555 requires 5% 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 Yamaha NS-555 weighs 20.00kg / 44lbs and the KLH Concord weighs 20.45kg / 45lbs. This makes the Concord 2% heavier than the NS-555.
Here is a comparison of how NS-555 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
 Max Input Power |
250 watts
vs
225 watts
|
Handle more power from your amplifier |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
 High Frequency Response |
35k Hz
vs
23k Hz
|
Generates higher frequency |
 Height |
979mm
vs
1026mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
765cm2
vs
805cm2
|
Takes less floor space |
 Sensitivity |
94 dB
vs
88 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
6 ohms
|
Less selective with amplifiers |
 Low Frequency Response |
28 Hz
vs
35 Hz
|
Generates deeper bass |
| General |
Yamaha NS-555 |
KLH Concord |
| Brand |
Yamaha |
KLH |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
100-250 watts |
up to 225 watts |
| Sensitivity |
88 dB |
94 dB |
| Impedance |
6 ohms |
8 ohms |
| Frequency Response |
35-35k Hz |
28-23k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
6.5" |
6.5" |
| Woofer Composition |
PMD cone |
Kevlar |
| Woofer Surround Material |
n/a |
Butyl Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Aluminum dome with waveguide horn |
n/a |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
5" |
No |
Physical Specs |
|
|
| Height |
979.5mm (38.6") |
1026.0mm (40.4") |
| Width |
222.3mm (8.8") |
212.0mm (8.3") |
| Depth |
344.5mm (13.6") |
380.0mm (15") |
| Weight |
20.00kg (44lbs) |
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 |
No |
No |
Other |
|
|
| Parts Warranty |
|
10 Years |
| Labor Warranty |
|
10 Years |
A generation apart: KLH Concord is the newer design, against a 2003 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | B | KLH Concord digs deeper - 28Hz against 35Hz. A subwoofer would even that out. |
| Amplifier needs | B | KLH Concord is more sensitive (94dB vs 88dB), so it goes louder on the same amplifier. |
| Amplifier match | B | KLH Concord is the easier load at 8 ohms. |
| Headroom | evenly matched | Similar power handling (250W vs 225W). |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Price | evenly matched | Much the same money ($1,000 vs $1,000 a pair). |
A Yamaha NS-555 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 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 35Hz 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.