Jeff Rowland Aeris DAC + PSU
Adding the brand new Power Storage Unit to the Aeris DAC
JRDG have just issued a very interesting new product: the Power Storage Unit, called PSU in short. Developed primarily to feed the Corus (and propell this preamp to absolute reference status in the process), the PSU can also power two additional components, for example the Aeris.
As I learned time and again, the power supply is any component’s achilles heel. While the Aeris’ external switching power supply is anything but an afterthought, the PSU is still likely to really transform the Aeris’ performance to new levels. I am basing this on the incredible results obtained with the new PSU when feeding the Corus preamp that is normally fed by a switching power supply that is very similar to the one used for the Corus.
The PSU is not a normal linear or switched power supply, nor is it a Battery power supply. The PSU is a very special new kind of external power supply that employs a large bank of ultra capacitors. The big advantage of this is that the PSU can supply lots of clean power instantly, and this is clearly audible in the absence of battery-typical effects that normally mar the otherwise clean sound, such as rounded off transients and a subjective slowing of pace. There is much more to say about the technical aspects and the effect on the Corus preamp, but this is already covered in the Corus + PSU review so please head over there for more info.
Unfortunately I have sold my Aeris a while ago but my friend Niels still has his Aeris and was nice enough to come over with it for an evening of listening. Just like me, he was very excited to hear what the PSU treatment would do for the Aeris.
To assess the differences, we first listened to the Aeris au naturel, with its own switched power supply, and I used a variety of powercords to make sure I obtained the maximum from it. What worked well in the past was either the latest version Harmonic Technology Pro ACII (to obtain a more relaxed, smooth and fluid sound) or a Furutech Apha3 (for a more sonorous timbre and to maximise dynamics and slam). A third cable was also tried: the Cardas Clear Beyond, which yielded more or less the best of the two aforementioned cables. Interlink used for the most part was a Cardas Clear XLR but the Cardas Hexlink Golden 5C XLR was also listened to briefly because that was the cable I used with my Aeris. Because Niels lives nearby and uses the Aeris on a day to day basis, it only needed a short warm up period. I gave it at least 2 hours and then we listened to a carefully pre-selected varied playlist containing various artists.
Just as with the Corus, it only takes minutes (I would even say seconds) to hear the huge improvement. In case anyone is afraid that the Aeris’ super-solid bass, or its lively performance, might suffer when fed from the PSU: you need not worry. All the Aeris’ inherent power is present entirely undiminished and the Aeris remains every bit the incredibly upbeat and energetic performer.
Soundstaging and Drive
Especially noteworthy is the improvement in soundstaging. The standard Aeris has a tendency to project the whole performance forward as whole, rather than having individual instruments reach their own relative front to back positions. This certainly plays a role in the DAC’s powerful delivery and makes for an exciting sound, but with my current system I have heard more 3D soundstaging and clearer layering from other DACs, such as the Wadia 521.
With the Aeris + PSU, there is now more distinct front to back layering and better definition of individual instruments within the stage. While not reaching Wadia soundstaging level, separate instruments are now more fleshed out and come across as more human and real.
The Wadia 521 has a relaxed and free-flowing nature which by comparison makes the Aeris sound a bit overly pushy at times, but this will be a highly system dependent aspect, and in other circumstances this property will translate to an impressive presence. For example, even in standard form, the Aeris worked wonders with the Magnepan MG3.6R speakers that I owned previously, when one of the Aeris’ most impressive aspects was actually its soundstaging.
Refinement and resolution
Resolution is an area where a huge improvement can be heard. The PSU 100% lays to rest any earlier concerns that I had concerning this area. The PSU now simply propells the Aeris all the way up there with the best. Treble has much more air and lost its slight edge, while simultaneously gaining low level detail and overall refinement, to arrive at a “Retina”-like resolution, just as happened with the Corus. There’s now incredible sharpness without the sound being edgy or sharp.
While the Wadia 521 sounded more refined and more airy in the treble than the stock Aeris, the PSU seems to further pull down the noise floor, to reveal new levels of low level detail, as well as further raising the overall transparency to a really impressive level. Needless to say, the Aeris + PSU clearly has more refined treble and higher overall resolution than the Wadia. But when thinking back of other reference level DACs I used, few if any DACs will match this combination of smoothness and superbly transparent and highly resolved sound.
While on the subject of Wadia, I should note that this brand normally has the upper hand in terms of bass heft and overall dynamics when compared to the large majority of other DACs. There is just an energy to this brand’s sound that is rarely matched. The Aeris (with or without PSU) however quite easily improves on the 521 (which is the best Wadia I have heard) in terms of dynamics and overall power, and the Aeris is almost as solid and powerful in the bass department.
Final area of improvement that the PSU brings is in the timbre, or tonality. Without PSU the Aeris has a decidedly non-synthetic timbre already but with the PSU the tonality becomes even more natural, and more neutral, making instruments as well as voices sound acoustically very convincing.
There is just not a single argument that can be raised against the PSU. It simply brings a formidable improvement across the board while introducing zero downsides. I ask of you: how often does this happen in the wonderful world of high end audio? If you own a Corus or Aeris or both, then I would strongly urge to consider adding the PSU.