Every once in a while, the reviewing malarkey unveils a product that is so exciting that all you can do is sit back and play as much music as possible before the plus size lady sings, or in this case the editor demands copy. This pairing from Aqua in Italy turned out to be just such a product, OK it’s two pieces but put them together and you have one hell of a digital streaming system.
The Aqua La Scala MkII is a DAC, an R2R ladder DAC that has been around for a few years but remains a very strong contender in a competitive field. I reviewed it for these pages in 2018 and got a very enjoyable result. The Aqua LinQ is its partnering streamer, it’s not your usual UPnP device that’s based on a common chipset but a modular design that can be fitted with renderers for different streaming protocols. This sample was supplied with something called HQPlayer, a software streaming engine that I’ve not seen embedded in a piece of audio hardware before but is rather the domain of the computer audio enthusiast with the inclination to go deeper.
Aqua (Acoustic Quality) offer a UPnP module for the LinQ and have a Squeezelite renderer option ‘coming soon’ but they have clearly taken a shining to HQPlayer and it’s not hard to hear why. What is hard to understand is that no-one else appears to have done the same. Maybe it’s not very well known; I hadn’t heard of it until now, and maybe it’s difficult to integrate into an app controlled streamer without the range of controls available on a PC. HQPlayer in software form is enormously configurable, confusingly so for the non-geek. You can stream all the key formats including RAW, upsample to 32-bit/1.536MHz (and downsample), choose from nine levels of dither, use one of 12 delta/sigma modulators and playback in up to 7.1 channels and that’s just skimming the surface. It makes JRiver look like child’s play and runs counter to those of us born and raised on the ethos of ‘less is more’. And yet in the hands of the engineers at Aqua’s Milan base, HQPlayer turns out to be quite remarkably transparent.
To get back to La Scala MkII Optologic to give it its full name, this is the middle model in Aqua’s three strong DAC range and is based on the company’s proprietary FPGA based digital decoding engine. It uses galvanic and magnetic isolation between engine and converter, discreet R2R ladder DACs (rather than chips) and has a pair of triode valves in its output stage – these can be seen if you peer through the slot on the front panel. The power supply for the anode on these valves is a virtual battery type and both analogue and digital halves of La Scala have their own low noise power supplies. Inputs include both flavours of coaxial (BNC and RCA), AES/EBU balanced, USB for PCM sample rates above 384kHz and DSD over DSD128 and the option of AT&T fibre. Then there tis he Aqua’s I2S connector for use with their CD transport and the LinQ, this uses a Neutrik ethercon RJ45 pro ethernet connector with an XLR style metal cover but can also be used with regular ethernet connections. A good quality AQLink cable is supplied with the streamer for obvious reasons and was used for the review. I also employed the power cables found in both boxes, atypically for high end audio these are good quality examples which is a nice touch.
The LinQ is controlled by Roon so you need a Roon Core running on the network. The way you set it up in Roon is slightly different to usual but not complicated; just pull down one of the switches on the LinQ to reveal the IP address of the HQP Core, choose ‘Add HQPlayer’ and enter the IP and with luck you will be away. Because our sample had already seen some shelves, I had to go to the LinQ’s IP on my browser and hit factory reset to get it working and in the process discovered that this is where system updates can be done when required.