In this review, we will be comparing Diamond 12.3 and Alpha T20, two Passive Floor-standing speakers from Wharfedale and PSB. Let's have a brief look at the main features
of Wharfedale Diamond 12.3 and PSB Alpha T20 first before getting into our more
detailed comparison.
What size room are the Wharfedale Diamond 12.3 and PSB Alpha T20 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:
In the following sections, we will get into more detail in order to better understand how the Wharfedale Diamond 12.3 and PSB Alpha T20 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
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through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both Diamond 12.3 and Alpha T20 are 2-way speakers.
| Driver |
Wharfedale Diamond 12.3 |
PSB Alpha T20 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
0.75-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 5-inch
|
2 x 5.25-inch
|
Diamond 12.3 features a 1" Textile Soft-Dome Tweeter and 2 x 5" Mica-infused polypropylene Woofer with a Crossover frequency at 2200Hz. On the other hand, the Alpha T20 features a 0.75" anodized aluminum with front waveguide Dome Tweeter and 2 x 5.25" Polypropylene Woofer with a Crossover frequency at 2500Hz.
Frequency Response
Diamond 12.3 has a frequency range of 45-20k Hz whereas Alpha T20 has a frequency range of 36-21k Hz. With a minimum frequency of 36Hz, the Alpha T20 can go significantly deeper on the low side and provide stronger bass compared to the Diamond 12.3's min frequency of 45Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Floor-standing class in our database.
Low Frequency
Floor-standing Speakers
High Frequency
Floor-standing Speakers
None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
Diamond 12.3 and Alpha T20 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Diamond 12.3 sensitivity is rated at 88 dB and the Alpha T20's is at 90 dB. This 2 dB difference makes the PSB Alpha T20 a more sensitive speaker compared to Wharfedale Diamond 12.3, 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. While using an amplifier within this range ensures the nominal performance , inputting a power that is higher than the max wattage can result in a damaged speaker.
Diamond 12.3 can handle a max power of 150 watts RMS from the amp the whereas Alpha T20 has a max power handling value of 120 watts RMS, 30 watts less than the Diamond 12.3.
Keep in mind that a higher max power handling value doesn't necessarily make that a louder speaker
compared to a lower max handling speaker. Loudness or the sound level is also impacted by parameters
such as Impedance, sensitivity and system efficiencies.
Input Type and Bi-Amping / Bi-Wiring
Both Diamond 12.3 and Alpha T20 features dual binding post speaker terminals for bi-amping or bi-wiring.
Wharfedale Diamond 12.3's Binding post terminals allows Bi-amping or bi-wiring
PSB Alpha T20's 5-Way post terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Both Diamond 12.3 and Alpha T20 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.
Physical Specs
Size of a speaker can sometimes become 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 Diamond 12.3's and PSB Alpha T20's external dimensions. Wharfedale Diamond 12.3 has external dimensions of 985.0 x 180.0 x 362.0mm ( 38-3/4 x 7-1/8 x 14-1/4inch) whereas PSB Alpha T20 has external dimensions of 869.0 x 212.0 x 250.0mm ( 34-3/16 x 8-5/16 x 9-13/16inch) .
PSB Alpha T20 is 116mm shorter and 112mm less deeper than Wharfedale Diamond 12.3 but it is also 32mm wider.
Below you can see the front view size comparison of Wharfedale Diamond 12.3 and PSB Alpha T20 in scale.
Comparison image of Wharfedale Diamond 12.3 and PSB Alpha T20 Size and External Dimensions
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 Diamond 12.3 is approximately 651.6cm2 / 101.0inch2 and base area of the PSB Alpha T20 is approximately 530.0cm2 / 82.2inch2. The Diamond 12.3 requires 23% more surface area than the Alpha T20 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 Diamond 12.3 weighs 19.50kg / 42.9lbs and the PSB Alpha T20 weighs 11.89kg / 26.2lbs. This makes the Diamond 12.3 64% heavier than the Alpha T20.
Here is a comparison of how Diamond 12.3 and Alpha T20'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 Wharfedale Diamond 12.3?
Here are the items that are included inside the box of Diamond 12.3:
Floorstanding loudspeakerGrille4 Spike feet (w/ locking collars)2 Jumper-bars (pre-installed)4 Isolation pucksUsers Manual
What's in the Box of PSB Alpha T20?
Here are the items that come with the Alpha T20:
2 Floorstanding loudspeakers2 Grilles8 Rubber feet8 Spike feet8 Hex-nutsQuick Start GuideWarranty Card
 Max Input Power |
150 watts
vs
120 watts
|
Handle more power from your amplifier |
 Sensitivity |
90 dB
vs
88 dB
|
Play louder with same amount of amplification power |
 Woofer Size |
5.25 inches
vs
5 inches
|
Larger woofer |
| Low Frequency Response |
36 Hz
vs
45 Hz
|
Generates deeper bass |
 High Frequency Response |
21k Hz
vs
20k Hz
|
Generates higher frequency |
 Height |
869mm
vs
985mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
530cm2 (212x250mm)
vs
651cm2 (180x362mm)
|
Takes less floor space |
 Price per pair* |
799USD
vs
998USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Wharfedale Diamond 12.3 |
PSB Alpha T20 |
| Brand |
Wharfedale |
PSB |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
30-150 watts |
15-120 watts |
| Sensitivity |
88 dB |
90 dB |
| Impedance |
8 ohms |
8 ohms |
| Impedance |
5 ohms |
n/a |
| Frequency Response |
45-20k Hz |
36-21k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5" |
5.25" |
| Woofer Composition |
Mica-infused polypropylene |
Polypropylene |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
0.75" |
| Tweeter Type |
Soft-Dome |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2200Hz |
2500Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
985.0mm (38.8") |
869.0mm (34.2") |
| Width |
180.0mm (7.1") |
212.0mm (8.3") |
| Depth |
362.0mm (14.3") |
250.0mm (9.8") |
| Weight |
19.50kg (42.9lbs) |
11.89kg (26.2lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF/Wood-grain vinyl |
MDF, Wood-grain vinyl |
| Available Colors |
Black, Oak, Walnut |
Black |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
Yes |
Yes |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |