Okto Research DAC8 Pro multi-channel DAC
On the NEBO 11 thread Ali Tait asked about my new Okto Research DAC8 Pro. I thought I’d write up my thoughts on the Okto DAC and also explain why I use multichannel DACs that are typically found in recording studios.
The simple answer is my three sets of speakers - Magneplanar MG2.5R, Linkwitz LXMini and Linkwitz LX521.4 - are all active dipoles. Digital crossovers/EQ for all three speakers are done in a 64bit environment (Jriver DSP) and make for a very flexible setup if you’re primarily listening to digital content. All the speakers have their own multichannel DACs and multichannel amps so switching from one to another is simply a matter of turning on the appropriate hardware and loading the x-overs in JRiver.
Anyway, onto the Okto Research DAC8 Pro (about £1k) which I’m now using in my main digital system: Fan-less i7 PC running JRiver>>Okto Research DAC8 Pro>>Apollon Audio NCMP8350>>Linkwitz LX521.4.
For the last four years I’ve been happily using a Mytek ADDA8x192. However, it is a 14 year old design using a 17 year old DAC chip. It is still in production and widely used in recording studios and still ranks highly in the Gearslutz loopback test.
Last year I came across the Okto Research DAC8 Pro (about £1k), a rather nice looking DAC from a small company in Prague. The design is simple, but elegant with input, sample rate /bit depth and volume level in large displays that are easy to read across the room. The Mytek is typical pro gear by comparison - lots of LEDs and small routing buttons etc.
So how does the Okto sound? Well, like nothing really. Essentially, a great recording will sound great, smooth detailed and dynamic without a hint of exaggerated highs or conversley, rolled off top end. it’s not going to cover up poor recordings’ faults, but neither do they become unlistenable. I can always try to spruce that up in DSP if I want to. I don’t want my DAC colouring my sound – there’s good DSP plug-ins including valve emulators for when I want a different sound. To be honest, with levels matched the Okto and the Mytek are fairly close from a subjective standpoint. That’s quite a compliment to the Mytek considering its age. There is a much bigger difference between the speakers than the DACs, that’s for sure.
https://i.imgur.com/OXRgd3I.jpg
But I can say with certainty that the Okto is the quietest DAC I’ve ever owned. With the Mytek there is a very slight hiss through the LX521s - ear next to driver – nothing at the listening position. With the Okto it’s dead silent, there is no speaker hiss whatsoever. This is borne out in their measurements which show an extremely low noise floor. However, while measurements can tell us a lot about a device, some are more important than others IMO. For me a multi-tone IMD test is one of the most revealing. This is a test most similar to music and here the Okto produces outstanding results, pretty much on a par with the Mola Mola Tambaqui, a 2 channel DAC which costs 10 times more. So with its low noise floor, and excellent low level linearity, jitter and IMD measurements there is the potential for the Okto to excel at retrieving low level detail. For my needs it fits the bill perfectly. But no matter how good the measurements are, at the end of the day our ears are the final arbiter as to whether we like the sound, and I do. As Siegfried Linkwitz used to say 'What is important to the eye is not necessarily important to the ear...,'
Okto are about to release a 2 channel DAC (with built-in Raspberry Pi option) which should perform even better than the 8 channel unit as they will sum the 8 DAC channels for an even lower noise floor. Okto offer a 30 day trial – so there’s the opportunity to try their product at home.
However, I should add a couple of caveats – mine has an issue with the remote so Okto are sending me a replacement unit. And there is a very long waiting list for both the DAC8 Pro and the new 2 channel unit. Mine took 4 months……
