Two tests in one review this week with the Quad Vena USB DAC amplifier ? main focus of this article ? along with the AudioLab 8200CD player ? reviewed in a different article. Two very good quality British systems, excellent quality as far as the Audiolab player is concerned. The idea of combining them intrigued us, to say the least. Can an excellent optical player paired up with a USB DAC deliver a better sound than it would with its own DAC? Here’s our answer.
The Quad Vena integrated stereo amplifier is an average power model equipped with a USB and S/PDIF DAC as well as a Bluetooth apt-X receptor designed to work with compact speakers or small floor-standing speakers. In other words, an extremely functional amplifier aimed at digital music enthusiasts who mostly use their computer or smartphone as an audio source. The Quad Vena delivers up to 45 W per channel into 8 Ohms, with an announced distortion rate of 0.0009% at 1 kHz for 10 W. These are reassuring numbers, better than what its competitors in Asia have to offer in terms of all-in-one amplifiers. Quad opted for a traditional class-AB amplification in order to get a soft and warm sound. The built-in DAC is a Cirrus Logic CS4398 model compatible with 24 bits and 192 kHz PCM audio stream via its S/PDIF inputs and 24 bits / 96 kHz via its USB B port.
The Audiolab 8200CD CD player with USB and S/PDIF DAC is based on the same idea. The British brand optimised its device to deliver a warm sound and ample sound stage. Bulky, heavy and using a large power supply, this DAC benefits from a pure class-A output stage. It uses today’s reference chipset, the 8 channel ESS Sabre 32 9010, which, when used in a stereo system, has the advantage of offering a dynamic range and a channel separation close to 133 dB ? as well as pin point accuracy. The built-in DAC is also compatible with PCM audio streams up to 24 bits and 192 kHz via the S/PDIF inputs and 24 bits / 96 kHz via the type B USB port.
Quad Vena: limited to 24 bits and 96 kHz via USB
If a built-in USB controller unable to let HD audio stream travel to a DAC which has the capacity to handle it might seem like a very strange idea, it is indeed what Quad and Audiolab did. Yet, there is an explanation for this choice which can be summarised in one word: Windows. This operating system (and it is the only one in this case) doesn’t natively integrate any driver allowing audio stream superior to 24 bits / 96 kHz or DSD to travel via a USB port. Class 2 USB audio devices are therefore not compatible. A specific driver programmed by the manufacturer of the USB DAC is then needed. Some brands decide to overlook this issue, which could be because they don’t have the ability to release such a driver or in order to focus on devices of higher quality, designed to handle 24/192 and DSD format via USB.
Quad Vena: Free your USB DAC with ASIO4ALL
It is possible to think of ways to get around the issue. For instance, it is possible to use a small digital transport such as the M2TECH HiFace 2 RCA, which will extract 24 bits and 192 kHz audio stream from a computer and redirect it to its S/PDIF RCA output. This way, a 24/192 audio stream can be directly sent to the DAC. Another option, which might not systematically work, is to install Foobar2000 and the free driver ASIO4ALL. You can then set the memory buffer to 2048 in order to get a 24/192 stream via your USB port. It works perfectly with the Quad Vena but we didn’t manage to get the same result with the Audiolab 8200CD.
The Quad Vena is clearly very well designed and equally well built. Its small size gives it a stocky aspect while its frosted anthracite grey finish and simple lines make it a really elegant object. The layout of its front panel is beyond reproach and each input can be selected via a dedicated button. The potentiometer is very pleasant to use and motorised for remote control use. The remote control is small but made of rather heavy aluminium which gives it a high quality feel.
Quad Vena: a flawless design
The connectors are mostly placed at the back of the Quad Vena and the layout is simply impeccable. There are two RCA stereo inputs, 3 S/PDIF digital inputs (2 Toslink and 1 coax) and two USB ports. The first USB port is a type B in order to let you use the Quand Vena’s DAC from any computer, while the other one, a type A, lets you connect an iPhone or an iPod. The Vena features three types of outputs: one pre-out RCA stereo for a possible connection to a power amplifier, and two S/PDIF digital outputs (coaxial and Toslink) which let you set up a passthrough from a digital source connected to the amplifier to another DAC or home cinema amplifier for instance. The screw terminals are made of plastic and are designed for a lateral insertion of the speaker wires. We had a difficult time taking the caps off to use our banana plugs… or maybe it was due to a paper-clip malfunction. What can be said about the connections? We can start by stating that this device features a very comprehensive panel of connections, especially since the amplifier is equipped with a Bluetooth apt-X receptor and a screw-on antenna. You can connect an HDTV or a computer to listen to MP3 or HD FLAC files as well as Deezer, Spotify, Qobuz and web radios or even connect a CD or Blu-ray player.
Testing conditions
We listened to the Quad Vena in various configurations, paired up with Monitor Audio Radius 270 floor-standing speakers and connected with Viard Audio Silver HD12 cables. In other words, we used speakers made for such an amplifier – with a pair of 10 cm drivers loaded in an average air volume conveyed by 2 bass-reflex ports, nothing fancy ? and excellent cables made in France. We tested four different sources: the Audiolab 8200CD via its analog RCA output first with a pair of Viard Audio Premium HD RCA then Viard Audio Silver HD RCA cables.
We then used the PopCorn Hour A410M multimedia player via its HDMI output and an HDTV via its optical output (Norstone HCS-500 HDMI cables and Audioquest Vodka Toslink). Lastly, we used a computer with Windows, Foobar2000 and the ASIO4ALL driver connected with the Audioquest Coffee USB cable. We played audio CDs, Deezer, HD FLAC files (up to 24/192 via USB). Films in DTS stereo were also used. As for the Bluetooth connection we just made sure it was working as we usually don’t listen to MP3 files.
Listening impressions
The Quad Vena delivers a very balanced sound even at low level. This amplifier’s sound signature, or at least its DAC’s signature, is relatively dry, which isn’t necessarily a drawback. There is no over-the-top treble, a lot of substance in the mediums and higher-bass and a good extension in the low-frequencies (although the speakers we used were limited in this range). The Quad Vena offers a coherent swiftness through the entirety of its bandwidth. Tracks such as Giorgio by Moroder or Get Lucky by Daft Punk (24/88 FLAC), which are very demanding regarding the transient regime in the lower frequencies, are very catchy and comfortably delivered.
Regarding the digital inputs, the Quad Vena was more pleasant to use via its Toslink input rather than its USB port. We used excellent quality cable (Audioquest Vodka and Coffee USB) in both cases, but the S/PDIF input delivered better results although we used identical FLAC files for both inputs (played on our computer and via the PopCorn Hour A410M). There was a greater harmony in the mediums, the bass was deeper and the treble was even smoother.
Yet, it’s via its analog inputs that the Quad Vena delivered the best sound, of course it was paired up with audiophile sources.
Aside from the Audiolab 8200CD player that we will come back to, the PopCorn Hour A410M, with its regulated power supply case and its ESS Sabre32 9023 DAC truly surprised us with its incredibly spacious sound stage. The double bass in Cheek to Cheek by Tony Bennett and Lady Gaga (FLAC 24/96) suddenly came to life, while both vocal tracks were right where they ought to be. Far From any Road by The Handsome Family (FLAC 16/44, opening song of the show True Detective) sounded extremely soft and smooth, percussions were a real treat to our ears and never took over the acoustic guitar.
With the Audiolab 8200CD player, the sound stage increases in density and roundness. The class-A stage output coupled with the very analytical ESS Sabre 32 9018 DAC works miracles. This is an excellent source for whoever is looking for an ?analog? sound signature, numerous digital filters are also offered. You can read more about this product in our review of the Audiolab 8200CD.
Our conclusion: if the built-in DAC of the Quad Vena is definitely convenient, this amplifier has even more to offer when paired up with a really good source equipped with an audiophile power supply.
