Sumiko S.5

Sumiko S.5The Sumiko S.5 really quite surprised us. A new brand, it is associated with the high-end Italian Sonus faber marque — though the Australian distributor clarified to us that although “part of the Fine Sounds Group group, it is not strictly speaking part of Sonus faber, although they do share some of the development team”. Still, Sumiko’s own subwoofer website pronounces them “a new product series by Sonus faber”, so we can remain surprised that the recommended retail price of this 8-inch subwoofer is a reasonably modest $999. And it is a pretty little thing, finished in a beautiful piano gloss, the shiny black cube (white is also available) held up from the floor by a four silvery legs, with Sumiko’s spiral logo illuminated on top.

The 210mm driver is mounted in the base of the unit, firing downwards. The feet give a clearance of around 50mm. The enclosure is sealed. There are 150 watts behind the driver. Unusually, these days, the amp is Class A/B rather than some digital thing.

Also unusual are the connection arrangements. There are three inputs, all mono, and no outputs. One input is LFE and this bypasses the low-pass filter. The next is line-level and this is, of course, under the influence of the filter control. There’s also a speaker-level input in the form of a Neutrik SpeakOn connection. The unit is supplied with a 10-metre cable terminated with a matching plug at one end and bare wires at the other for connection to speaker outputs on an amplifier. This also runs through the low-pass filter.

If you’re using the line input you will need to use an RCA line splitter. You should check that this won’t end up turning your stereo system mono. The speaker connection provides two active and one return wire. A high-input impedance from this should leave the speaker signal unaffected.

There are two level controls: one for the LFE input, the other for the two other inputs, so they can be set independently. A polarity reversal switch is provided.

A trick: if your receiver doesn’t handle bass well — perhaps fails to feed the bass diverted from small speakers at the correct level into the subwoofer output — then you can use a dual connection to the subwoofer. Set the receiver to ‘Large’ for your front left and right speakers, and feed those channels to the subwoofer from the speaker outlets. Also connect the LFE. Then you can balance the bass between the two sources to the subwoofer using the two level controls.

Sumiko range

As usual, I installed the subwoofer in the test corner — you typically get a six-decibel output boost in a corner location — set the receiver’s crossover to 80Hz and balanced the level. The Sumiko S.5 proved a lively little subwoofer, delivering punchy and effective mid-bass, extending into the upper reaches of the deep bass. It nicely covered the range required for full delivery of a kick drum and bass, both acoustic and electric.

In handling this music it was controlled and precise, avoiding any sense of lumpiness or monotonality. The volume levels were more than adequate, even for my large-sized lounge room.

Sumiko S.5What was missing was much in the way of a real deep underpinning to music. The large orchestral drums on Telarc orchestral recordings were delivered with a reasonably satisfying thud, but without that sense of deep, powerful energy such drums are intended to provide. There were no infrasonics of course. Likewise, while the frequent deep bass lines in Wendy Carlos’ ‘Switched On Bach’ were largely satisfying to the ear, they lacked the truly deep grunt that bigger subs can deliver.

For movies the subwoofer did a generally good job covering the bulk of LFE content, but again of course missing out on the really deep rumbling. Actually, to be more specific, there was a trade-off. At moderate volume levels (that is, levels which were room filling, while still well below reference level) there was a good sense of deep bass, and with bass impacts the unit maintained excellent control and composure. The thump of explosions were suitably powerful for a quite exciting performance.

The only real limitation was running extreme material at extremely high levels. For example, a test DTS-CD with some ridiculously deep and power infrasonic stuff seemed to have even its higher frequency bass sketched out rather than fully realised.

The Sumiko S5 would seem to be an ideal choice for coupling with high-quality satellites or small bookshelf speakers, and should prove well worth the money for anyone in that market. And its sense of style, no doubt inserted by those enthusiastic Italians at Sonus faber, is certainly a bonus. SD

Sumiko S.5

Sumiko S.5                                              
Price: $999

+ Very good value for money
+ Fine musical performance
+ Useful connectivity options

- High 3rd/2nd harmonic distortion
- Not effective for deep bass

Drivers: 1 x 210mm, downwards firing
Enclosure: Sealed
Inputs: 1 x mono line input, 1 x LFE, 1 x mono speaker level input (SpeakOn)
Outputs: Nil
Low-pass crossover: 30-120Hz
Quoted power: 150 watts
Measured room response (pink noise -6dB): 33-146Hz
Level at 20Hz: -28dB
Dimensions: 335 x 285 x 315mm
Weight: 14kg
Warranty: Two years

NOTE: In order for the Sumiko S.5 Subwoofer to integrate correctly with your main loudspeakers, you will need to set the subwoofer's volume, phase and crossover frequency controls correctly. You can read an article on a simple, effective method of how to do that HERE