I would just like to provide some impressions about the Graham Slee Novo headphone amplifier. I hesitate to call this a review for one simple reason; in my opinion it is impossible to review just the Novo as I am really describing everything in the audio chain. let's face it, when we provide impressions of say an amplifier, you really can't "tease" the amps sound apart from everything else, really all you can do is describe how the whole system sounded together. Sure if your memory is somehow constructed in such a way that you can store accurate impressions of every part of the audio chain as an isolated component, then perhaps you can say more about component A with component B, but that must be so very difficult.
I used the Novo for several hours of listening with my Rega Apollo CD player and either my HD 650s, or my DT 880 600 ohm version. I used quite a wide variety of music to audition the Novo (which had been burned in for about 200 hours by my friend who owns the Novo). Perhaps when time permits I will do a more thorough review of the Novo with a description of performance by describing the individual test tracks used and with what particular headphone. At this point I just wanted to offer some general impressions of the Novo.
The Novo seems to be a very versatile amplifier. I could not believe that such a small amplifier could generate such an impressive sound while driving 300 and 600 ohm headphones. I found the Novo to be very musical and engaging. Despite the fact that based on specifications alone the Novo wouldn't command the lower frequencies that well, but I was quite pleasantly surprised in this area. I have several reference tracks that provide a significant test of an amplifiers low frequency capability (Holy Cole - One Trick Pony, Mark Knopfler - El Macho, Chemical Brothers - Come Inside, Peter Garbriel - No Way Out etc). The Novo was actually very good and provided me some very articulate bass reproduction. I try to listen to the mechanics of the sound, but the Novo was so engaging I found myself just enjoying the music as a whole. That said, I can say with some certainty that the Novo has plenty of impact and does quite a respectable job down low. Timbre and tonal qualities were well reproduced and in general as far as I can tell, pretty accurate. I guess it is most accurate to say that I like how the Novo is voiced. It is a capable and agile little amp.
I found it to have that British sound signature which I tend to like, working toward an accurate and neutral presentation, but stopping short to have enough colour added to present the material musically. I found the mids very nice and present enough to bring out the music and voices well with very good control. The highs were also quite nice, never harsh or strident, just a nice balanced approach being rolled off just enough to take some edge away without muffling the sound. At one point I just put on Pink Floyd - The Wall and listened to almost the entire work. I just found how the Novo handled things was so very proper, never jaw dropping brilliant, but always right and always highly musical. I was trying to A/B it against either my Valhalla or Creek integrated, but I found the Novo so enjoyable that I quickly stopped and just used it.
I certainly found the Valhalla had some richness and deeper depth to it than the Novo, but it wasn't a huge performance edge either. The Valhalla has more bass, but I think the Novo provided better control of the bass overall. The mids through the Valhalla were more vibrant, but I felt the Novo did perhaps a slightly better job seperating the mids out from the sound, providing a Grado like voicing. I did not have any Grad cans left to use with the Novo, but I feel there might be some decent synergy there with something like the HF2 or RS1 where the highs are more controlled than with say the 125, 225, 325s. I loved how the Novo brough some really nice sparkle to my 650s, which while I do not find them veiled, they are rolled off in a way that is a 650 signature we can all hear. I can only say that until I really dig deep into the Novo that without a doubt in my mind it is a great little amp and well worth an audition. I think Graham Slee has a very good ear for music and he can voice his components in such a way that they will never be dull or over-bearing. Poise and balance would be a few adjectives I feel the Novo warrants. I realise this is far from a review, that is why I call this an impression. It would be great if other Novo users/owners could chime in and add their thoughts.