[Review] Astin Trew Concord - powered USB cable system

Astin Trew Concord powered USB cable system

More power to USB DACs

Product name: Astin Trew Concord powered USB cable system.
Manufacturer: Astin Trew - UK
Cost: 699 UK pounds. (Currency conversion)
(YMMV)

Reviewer: Nick Whetstone - TNT UK
Reviewed: March, 2014

I'm now firmly entrenched as a computer audio source user. I look at my CDPs gathering dust on the shelf and wonder if I will ever use them again. A USB DAC offers me not only the convenience of not having to get up and put another CD in the drawer, but better sound quality than I thought that I would ever be able to afford in my home system. As an advantage (or should that be disadvantage?) they are tweakable, not so much internally as was the case with a CDP, but with accessories like the Concord powered USB lead that is the subject of this review.

The Concord is manufactured by Astin Trew, and consists of a Y-type USB cable connected to their own 'Never Connnected' power supply. I've previously reviewed several USB cables from the likes of KingRex, iFi, and Elijah Audio. The U-Arty cable from KingRex, and the iFI Gemini, can be used with their power supplies, or others, but the Concord is supplied as a 'powered cable' ie with a dedicated 5 volt power supply.

One thing that you must check before purchasing the Concord is that your USB DAC can accept power from an external PSU, ie that it does not have an internal power supply of its own. Astin Trew have started to make a list of USB devices that will work with the Concord, and you can also check with the manufacturer of your device if you are not sure.

Starting with the cable, the Concord uses what appears to be much smaller conductors than the KingRex U-Arty or iFi Gemini. They are clearly made to a very high quality but I wouldn't risk being as rough with them as the Gemini or U-Arty. I don't mean that they are not well-built, simply that they are less substantial in their size. The advantage of the less substantial cabling is that they are very flexible, and therefore less likely to dislodge a lightweight DAC from its shelf. It looks as though the conductors are twisted, and then sleeved in braided cotton insulation (a bit like the TNT Shoestrings), and the signal conductors and power are kept separated from each other until they actually enter the USB plug that goes into the USB device. The signal conductors are PTFE sleeved and shielded. The cable design is correctly rated at 90ohms as specified for USB data transmission, to ensure optimum operating capabilities (and unlike most USB cables on the market today ).

Astin Trew supply two options for the cable. The first is a more conventional type with a type-A USB plug to go into a computer, a type-B plug to go into the USB device, and a locking 3-pin power plug that connects to the power supply. The other is called the 'socket option, and has the power plug, the type B USB plug for the USB device, but a type-B socket on the other end of the signal cable. I would have thought a cable with a type-A socket for the USB device would have been more popular for users of devices like the M2Tech hiFace DAC or converter, Devilsound DAC, Dragonfly DAC. Of course you can always use a converter, as I did with the hiFace DAC.

[Astin Trew Concord cable.]

Interestingly there appear to be no RFI blocking devices on the Concord cable so I am guessing that Astin Trew have found that tightly twisting the conductors does an adequate job. The cable is also much shorter than the U-Arty or Gemini cables which could account for it not requiring so much protection. Astin Trew told me subsequently that they had experimented with RFI blocking but found it not to be necessary.

The power supply side of the Concord uses what is known as a 'Never Connected' power supply. Well it is plugged into the mains supply, and switched on, so what does this mean? It means that it takes it power while it is not connected to the mains by only taking it at certain moments. Think of it like this: you can read this review while your computer plays music at the same time. That's because the computer is not continuously doing one job but many at the same time. And it does that by multitasking. In a very small moment of time it may 'look' at the keyboard to see if you have pressed a key, then the next small moment, it gets some data from a CD or off your hard drive so it can play the music, all while it checks to see if your monitor display needs refreshing. Because these moments of time are so small, we don't notice the gaps when it is not responding to our keyboard, or doing something else but they are there. And that as I understand it is how the 'Never Connected' power supply works, ie by switching off the connection to the mains for fractions of a second while the power is supplied to the device.

Astin Trew kindly supplied this explanation about the 'Never Connected' supply:

"The Never Connected PS design uses two sets of capacitors, whilst one set is charging, the other is disconnected and discharging, the first set charge again, and discharge into the second set. The first set do not charge from the mains when the alternating mains current is at 0V because is has been found that this is where much of the ‘noise’ on the mains resides. So the never connected design offers isolation from the mains in a way that fundamentally reduces the mains noise entering the DC voltage output and is designed to isolate its own inherent switching ‘noise’ as well."

[Rear view of Astin Trew Concord powered USB cable system]

The power supply unit is a smallish item measuring approximately 200 mm long, 100 mm wide, and 55 mm high. The case is an attractive aluminium extrusion type with the sockets on the rear panel together with an on/off switch. The front panels houses a small LED. The whole item is designed and manufactured in the UK. Astin Trew were keen to point out that the power supply is designed and optimised to work with USB equipment rather than being an 'off-the-shelf' item.

That's the theory so how does this all work in practice? The test system used was my audio PC running Audiophile Linux and JPlay (in Windows 8), three USB DACs, the M2Tech hiFace DAC (with an adapter), the iFI iDAC, and the Miniwatt n4, with amplification by the Clones Audio 25i, or my own chip amplifier. Speakers were my modified Mordaunt Short Pageant II's.

I had been using the Paul Hynes SR3-05 power supply to power the DACs via the other USB Y-cables: the Elijah Audio BPM, the KingRex UArty, the iFi Gemini, and my own TNT 221. I've said this before but it's worth repeating for this review, that although a 5v battery supply is very good, and circumvents any problems with a poor mains supply, I find that a good mains supply is much preferable.

I was informed by Astin Trew that the Concord needs quite a bit of burning in to sound its best, and that turned out to be the case. Initially it sounded very impressive but with marginally too prominent bass, and a slightly 'shut-in' sound. As the hours of use went by the bass became nicely integrated, and the music 'opened out'.

[Astin Trew NC label.]

When I was happy that the Concord was sufficiently burned in, I began by listening to the system using the Paul Hynes SR3-05 supply with the iFi Gemini cable. I have my favourite review tracks on a USB stick for two reasons. Firstly they are easy to access, and secondly, I am a firm believer that the quality of music played off a solid state device like a USB stick is better than off a rotating hard drive. Hopefully in the not too distant future we will see the price of large SS hard drives drop to a point where we can keep all our music on one.

Next I swapped out the SR3-05/Gemini for the Concord combination and listened to those same tracks. I then went back to the SR3-05/Gemini, and repeated this process over a week. The result was a small but definite victory for the Concord (with all combinations of DAC and playback software but seemingly more-so with the hiFace DAC). There was a very slightly blacker background that resulted in marginally more detail, and again slightly, deeper and more defined bass. I would say that overall control of the music was slightly improved too. Both PSU/cable systems raised the performance of all three USB DACs from very good to exceptional. I would imagine that they would compare very favourably with more upmarket USB DACs, perhaps even surpass some! For instance I suspect that a hiFace 2 USB converter with a Concord would come very close to, or even surpass the Evo. Tom Rich actually compared the hiFace 2 against the Evo in this TNT article but unfortunately I didn't have an Evo to try against the hiFace TWO/Concord.

None of the other USB cables that I had available had a connector for attaching them to the Concord PSU so I couldn't try them together, and am therefore unable to say how much of the improvement is down to the cable. In my experience the biggest improvement by far, comes from the power supply, but it's also clear that the USB cable can and does have an affect on the sound too. From the results, the Concord cable(s) certainly didn't let the side down, and there was no audible signs that a lack of RFI protection was missing.

Looking at the Concord system in terms of value, a good starting point is to compare it to the Paul Hynes SR3-05/iFi Gemini combination. The latter costs around 435 UK pounds while the Concord comes in at 699 UK pounds. That's a 264 pounds (33%) difference but the Concord does perform slightly better, and in terms of the overall cost of a system, I would be prepared to pay that 264 pounds for the improvement that it brings. As ever, small increments cost more at the higher end of hi-fi reproduction, and (with a decent USB DAC) the Concord certainly takes us nearer the peak.

You may be questioning the wisdom of buying something like a hiFace DAC and a Concord system (~1050 euros) instead of buying a more upmarket USB DAC such as the Evo (~400 euros) that presumably comes with a decent power supply. The advantage that I see is that the design of power supplies doesn't tend to advance at such a rate as USB DACs. So if you have a hiFace DAC and a new version is significantly better, you only need to replace the DAC, and not the power supply. We've seen USB DACs improve substantially over the last five years so I would prefer to buy a lower priced one with the aim of upgrading in the not too distant future, while I held on to a (very) decent power supply such as the Concord that didn't need replacing. So it may be initially more expensive to buy a cheaper USB DAC and Concord but work out cheaper in the long run if you wanted to upgrade the DAC frequently. And I would put my money on the hiFace/Concord combination sounding better than the Evo anyway.

In conclusion, the Astin Trew Concord is a very impressive piece of kit, and does 'what it says on the tin'. I was slightly surprised that something could improve on the Paul Hynes SR3-05 but then I was surprised when that SR3 improved on the SR1. I don't know if we can get much better than the Concord but for now what I can say is that it enabled me to hear deeper into recordings than I have ever done previously. In some sessions I wondered if I honestly needed anything better to listen to. Of course if I lived with that set-up for a few months I would probably get that old audiophile twitch and start thinking about a tweak or two but these days, with a computer source, decent DAC, cable and PSU like the Concord, I am much more content with my hi-fi than I have ever been. If you have a good USB DAC (and that doesn't necessarily mean expensive) that runs off the 5 volt source from the host computer, and want to squeeze the very best out of it, the Concord must be on your shopping list. It's simply the best USB DAC power source (and cable) that I have heard to date.