Home Review Isotek Aquarius V5 – central powerhouse

Review Isotek Aquarius V5 – central powerhouse



  • Brings calmness
  • And focus
  • High and Low current
  • Looks good


  • Price has become steep

Price: € 2499

Build quality
Isotek Aquarius V5


As most Alpha Audio readers will know by now, we are currently busy developing a test to objectively identify the qualities of a power conditioner. This will not happen overnight, but the start has been made. Of course, we will not stop with the (partly) subjective mapping of our findings. And the candidate in this test is the Isotek Aquarius V5. The successor to the well-known Aquarius EVO3. We have both models in house (thanks to Keith Martin).

Why Isotek went from the EVO3 version to the V5, you can read in our review of the Isotek Titan V5 which is now quite permanently included in our reference system. The reason is simple: it provides a much finer, more calm and more spacious soundstage.

Isotek Aquarius V5

The Isotek Titan is only for power amplifiers and “heavy duty” components. The filter is not suitable for sources. Now that may sound crazy: if a filter has a lot of capacity, it can work for any device, right? Well… no. A filter always works optimally with a certain load. So it is up to the manufacturer to choose which load he/she optimizes a filter for.

The Titan is optimized for heavier loads: the layout and components are adapted accordingly. The Aquarius V5 (2500 Euro) has both two outputs for power amplifiers (High Current) and four outputs for sources (Low Current). The filtering is different for HC and LC. And that can also be seen in our measurements. More on that later.

By the way, the principle of ‘Direct Coupled‘ is the same for both the sources and the high-current output. Isotek tries to make the filter layout in a certain way that it looks like a device is directly coupled to the grid. Basically, it comes down to the fact that there should be no extra resistance on the power line. More resistance makes for sluggishness and lifeless playback (especially with high-current devices). No one wants that.

On the back of the Aquarius, we see four regular outputs (6A) and two high-current outputs (16A). Then there’s a Powercon input. You can use that to connect other Isotek conditioners. Handy. And a nice extra is that you create a real star-ground, which has advantages in terms of eliminating any hum and cleaning up the earth. A problem that until a few years ago was not really known to audio enthusiasts.

New enclosure

As with the Titan V5, the enclosure has been completely redesigned. And we must say: it looks really sleek. Now the previous design had been around for a while (about eight years, I think), so an update was no unnecessary luxury.

With the new design, of course, everything is designed to fit neatly. On the Aquarius two Titans fit perfectly side by side, to name but one. We would definately like that in our system! As with the previous model, you get – very nice – a nice power cable to bring the Isotek Aquarius V5 to life…

Type test
Single Test
Accessory type
Conductor material
Type of conductor

Winkels met Isotek

Schoenmakersstraat 19
6041EX Roermond, NL
Grotestraat 23
5931 CS Tegelen, NL
St. Ceciliastraat 28
5038 HA Tilburg, NL
Breestraat 146-148
2311CX Leiden, Zuid Holland, NL
Hermesweg 2
3741 GP Baarn, Utrecht, NL
Korevaarstraat 2 e-f
2311 JS Leiden, NL
Beethovenstraat 9-b
1077 HL Amsterdam, Noord Holland, NL