In this review, we will be comparing ASTON and R-51M, two Passive Bookshelf speakers from Wharfedale and Klipsch.
Let's have a brief look at the main features
of Wharfedale ASTON and Klipsch R-51M first before getting into our more
detailed comparison.
| Key Specs | Wharfedale ASTON | Klipsch R-51M |
|---|
| Brand | Wharfedale
United Kingdom · founded 1932 | Klipsch
United States · founded 1946 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Soft-Dome | 1" Tractrix Horn |
|---|
| Woofer | 6" | 5.25" Copper-spun IMG |
|---|
| Frequency response | 55-20k Hz | 62-21k Hz |
|---|
| Sensitivity | 86 dB | 93 dB |
|---|
| Impedance | 4 ohms | 8 ohms |
|---|
| Power range | — | Up to 85 watts |
|---|
| Weight | 7.98kg / 17.6lbs | 5.00kg / 11lbs |
|---|
| Dimensions (H x W x D) | 13-3/8" x 7-7/8" x 10-1/16"
339.7 x 200.0 x 255.6mm | 13.3" x 7.0" x 8.4"
338.0 x 178.0 x 215.0mm |
|---|
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both ASTON and R-51M are 2-way speakers.
Wharfedale ASTONKlipsch R-51M
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Wharfedale ASTON |
Klipsch R-51M |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 6-inch
|
1 x 5.25-inch
|
ASTON features a 1" Soft-Dome Tweeter and 1 x 6" Woofer. On the other hand, the R-51M features a 1" Tractrix Horn Tweeter and 1 x 5.25" Copper-spun IMG Woofer with a Crossover frequency at 1660Hz.
Frequency Response
ASTON has a frequency range of 55-20k Hz whereas R-51M has a frequency range of 62-21k Hz. With a minimum frequency of 55Hz, the ASTON can go significantly deeper on the low side and provide stronger bass compared to the R-51M's min frequency of 62Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Bookshelf class in our database.
Low Frequency
Bookshelf 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
ASTON is a 4 ohms speaker compared to the R-51M 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 ASTON can provide this impedance level.
These two speakers also have different sensitivity levels. ASTON sensitivity is rated at 86 dB and the R-51M's is rated at 93 dB. This 7 dB difference makes the Klipsch R-51M a more sensitive speaker compared to Wharfedale ASTON, hence will play louder with the same amount of watts.
Sensitivity
Bookshelf Speakers
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
ASTON features Single Gold Plated Binding Posts - 5-way type posts and R-51M has a Single Gold Plated Binding Posts - 5-way type posts. None of these speakers feature bi-amping/bi-wiring.
Klipsch R-51M's Single Gold Plated Binding Posts - 5-way 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 Wharfedale ASTON's and Klipsch R-51M's external dimensions. Wharfedale ASTON has external dimensions of 339.7 x 200.0 x 255.6mm () whereas Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm (13.3 x 7.0 x 8.4inch).
Wharfedale ASTON is clearly the larger of the two speakers. Its body is 22mm wider, 1.7mm taller and 40.6mm deeper than Klipsch R-51M.
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.
Wharfedale ASTON needs about 34% more floor or shelf area. Wharfedale ASTON is 41mm deeper, so it stands that much further out from the wall.
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 Wharfedale ASTON is approximately 511.2cm2 / 79.2inch2 and base area of the Klipsch R-51M is approximately 382.7cm2 / 59.3inch2. The ASTON requires 34% more surface area than the R-51M 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 Wharfedale ASTON weighs 7.98kg / 17.6lbs and the Klipsch R-51M weighs 5.00kg / 11lbs. This makes the ASTON 60% heavier than the R-51M.
Here is a comparison of how ASTON and R-51M's weights compare with the average, max and min weights in Passive Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of Klipsch R-51M?
Here are the items that come with the R-51M:
- 2 Bookshelf loudspeakers
- 2 Grilles (installed)
- 8 Self-adhesive rubber feet
- Quick Setup Guide
- Important Safety Instructions
- Warranty Information
 Woofer Size |
6 inches
vs
5.25 inches
|
Larger woofer |
|
Low Frequency Response |
55 Hz
vs
62 Hz
|
Generates deeper bass |
 Sensitivity |
93 dB
vs
86 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
 High Frequency Response |
21k Hz
vs
20k Hz
|
Generates higher frequency |
 Height |
338mm
vs
339mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
382cm2
vs
511cm2
|
Takes less floor space |
| General |
Wharfedale ASTON |
Klipsch Reference R-51M |
| Brand |
Wharfedale |
Klipsch |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Sensitivity |
86 dB |
93 dB |
| Impedance |
4 ohms |
8 ohms |
| Frequency Response |
55-20k Hz |
62-21k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
6" |
5.25" |
| Woofer Composition |
|
Copper-spun IMG |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Soft-Dome |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
1660Hz |
| Firing Direction |
n/a |
rear |
Physical Specs |
|
|
| Height |
339.7mm (13.4") |
338.0mm (13.3") |
| Width |
200.0mm (7.9") |
178.0mm (7") |
| Depth |
255.6mm (10.1") |
215.0mm (8.5") |
| Weight |
7.98kg (17.6lbs) |
5.00kg (11lbs) |
| Enclosure |
|
Bass Reflex |
| Finish |
Wood/venner |
MDF/Wood-grain vinyl |
| Available Colors |
Walnut |
Black |
| Mounting Bracket |
|
No |
| Recommended Stand Height |
n/a |
24-28" |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
n/a |
No |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |
A generation apart: Klipsch R-51M is the newer design, against a 2014 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | A | Wharfedale ASTON digs deeper - 55Hz against 62Hz. A subwoofer would even that out. |
| Amplifier needs | B | Klipsch R-51M is more sensitive (93dB vs 86dB), so it goes louder on the same amplifier. |
| Amplifier match | B | Klipsch R-51M is the easier load at 8 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Size | depends | Klipsch R-51M is easier to place; Wharfedale ASTON is bigger, which usually goes with fuller bass. Your room decides. |
A Wharfedale ASTON B Klipsch R-51M
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?
Klipsch R-51M 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 62Hz anyway, so judge these on the other rows instead. If your amplifier is modest, vintage or valve-based, Klipsch R-51M 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.