SPL Dynamics S2604

Four channel amplifier with quite large power rating of sixty-five watts per channel and exceptionally able crossover section. It features gold plated RCA inputs and a set of RCA outputs to feed another amplifier. The power and speaker terminals blocks are machined from a metal billet with Allen headed grub screw fixings for bare wire or bootlace crimp use rather than forks and look very well engineered as well as gold plated. The thick name plate on the top can be unbolted and flipped by 180 degrees if your install’s look needs it.
Each pair of channels gets an input gain control, plus frequency selection potentiometers and a switch to choose which highpass or lowpass filter is on or off. As they range from a low 15Hz to 4kHz on the Highpass filter and 40Hz to 4kHz on the Lowpass filter and you can use both filters on any pair of channels at the same time, you can configure this amplifier to run bass with a subsonic filter or as a bandpass setting to run midbass and tweeters for an active component set. In fact this amplifier was used to test the somewhat nutty Ground Zero Pro audio style components (reviewed here) and was perfect for the job.
The end panels are chromed and the adjuster pot heads line up perfectly with the drilled holes (which is more unusual than you might think) and a single socket serves to act for high level input via the supplied plug loom thing.
– Class AB
– 4 x 65w RMS @ 4 Ohms
– 4 x 100w RMS @ 2 Ohms
– 2 x 200w RMS @ 4 Ohms bridged
– Aluminium heatsink with name plate bolted to top (can be swivelled by 180 degrees) chromed end panels
– 8Ga. Power Terminals with Allen headed grub screw bare wire socket connection
– High level connection via single Molex type socket loom supplied
– Gold Plated 4Ch RCA input and 2Ch output
– 24dB per Octave high/low pass crossovers
– Input sensitivity: 0.2V to 4.5V
– Stereo, & bridged operation
– Frequency response 20Hz to 30kHz
– Signal to Noise Ratio not quoted
– Channel separation 55dB
– High Pass Filter 15Hz to 4kHz
– Low Pass Filter 40Hz to 4kHz
– Fuse Rating 25A x 2
– HxWxD(mm) 54 x 220 x 320mm
Review by Adam Rayner
Under normal distribution circumstances, this would be around a £325 product. However, as it sold direct by Car Audio Direct it makes a nutty deal by removing one whole layer of trade. The Finns are known for their incredible engineering skills and indeed, the whole of Scandinavia is famed for the incredible quality of the loudspeakers a few companies from there make.
That and phones of course.
This amp is obviously from a family of utter nutters and one has that a small brand high excellence of design thing going on. I don’t know how much more it costs to add a single control to an amplifier’s design but I do know that the control options that the SPL Dynamics designers have gone for have resulted in a very clever class-leading product. It’s clear that along with Diamond Audio the SPL Dynamics designers know they are selling to a cognoscenti audience. The likes of the Sony and Blaupunkt are strictly mainstream in appeal and are not nearly as complex to set up as the SPL Dynamics S2604.
The crossovers are smooth sounding and obviously classy in their slopes and sound. You set these and the stuff you want to filter out is well removed, although smoothly enough to be musical. Again, I don’t know why more makers don’t bother to invest their amplifiers with 24dB per Octave crossovers. This set is a peach.
As soon as it fired up on the test Morels and mad ovals I use it was clear that this amplifier was about a big bold brash sound. The music hits like a weapon, with great edges and speed but not, it has to be said all that much delicacy nor sweetness. It hit me in the chest, raising some full on 125dB well behind me in the test room, with no discernible stress at all when it was still giving some 121dB. This is one loud amplifier.
I had a good go on the crossovers and found them easier to comprehend than some far less clever systems with confusing switchgear and yet smooth in effect. There were bell trees and tinkly percussive moments in the material I was playing and it seemed that the amp liked this sort of material. So again, hardly surprising given the very brand name (SPL Stands for Sound Pressure Level or LOUDNESS) but this one is another for lovers of hard aggressive tunes and those who like monster bass and cutting highs in a street bass stylee.
Able and meaty with a tremendous VFM factor, this is good looking and seems exactly as if it shouldn’t be in this price bracket – but then the Diamond Audio D1 300.4 was even madder in that direction.
Shiny, big and clever.
Overall 8.4
Sound Quality 7
Power Output 8
Features 9
Build Quality 9
Value For Money 9