Chiarra initial impressions after 250 hours
Like most amplifiers, the Chiarra needs some time to run-in from new - during which time the sound becomes noticeably smoother, detailed and more open. Shaun Williams, the supplier of the kit, recommends a period of 500 hours for the burn in to be complete. Once settled after 250 hours, the impression is of a very transparent sound, with excellent depth, detail and stereo imagery. Treble of the Chiarra is both detailed and smooth, with no hint of harshness or glare. Indeed it is reminiscent of the clean smoothness of valves, with much of their characteristic transparent midband. Bass, on the other hand, is of the solid, well-controlled 'dig deep and shake the floorboards' variety - the sort you're unlikely to get from any valve amp. In short, it combines valve-like mid and treble with the best kind of transistor bass and lots of power on tap, even when driving insensitive headphones.
I find the amp very easy to listen to, due to the lack of any harshness or sharpness. While it is easy on the ears, there is no shortage of analysis, with the instruments easy to separate and parts of studio mixes revealed clearly - a very enjoyable sound. Soundstaging is excellent, with a fine sense of depth and breadth. The amp does not land the performers in the middle of your head, but presents them slightly in front of your head which is a welcome relief, it is very similar to listening with a crossfeed device. I hesitate to use the words 'laid back', because that would create the wrong impression, but the Chiarra certainly doesn't create an up-front 'in your face' type of sound. Perhaps it's the lack of colouration which is responsible for this effortless fatigue free delivery of the music.
Sometimes I wonder whether the astonishingly deep, powerful bass is just slightly over-played, at the expense of the mid and treble presence, adding just a touch of extra weight. Then I'd play another piece if music and marvel at this amps ability to reproduce rapid bass rhythms and tunes, while conveying orchestral scale and hall acoustics with convincing realism. The Philips HP 890's are a very bass heavy headphone and the bass is certainly portrayed on a much more stygian scale than when listening with the AKG K501's. Having said that, the AKG's certainly sound a lot better in the bass department when being driven by the Chiarra - with the X-Can V2 they sounded very light indeed.
This is how I find the sound after a pretty short burn in period of 250 hours and using the Burr Brown OPA2228 Op Amp instead of the LF353 Op Amp which came supplied with the kit. If the sound quality stays as it is during the next 250 hours of burn in, I'll be happy - If it improves even further then that's an added bonus! I will be experimenting with other Op amps over the coming weeks and will upload my opinions to the Op Amp page after prolonged listening sessions so - stay tuned.
Since writing the above I have purchased a pair of Sennheiser HD 600 headphones and the Chiarra really does bring the best out of them. I worked closely with Graham Slee of gspaudio helping to perfect his "Solo" headphone amplifier and we modded the Solo around the HD 600 headphones with the end result that Sennheiser have chosen the Solo amp to demonstrate their flagship HD650 headphones at all the UK Hi-Fi shows this year (2004) full details here
I give mention to the Graham Slee Solo amp to highlight just "how" good the Chiarra is. Compared to the Solo the Chiarra really is in a different league picking out every last detail in a recording and presenting the music effortlessly..... sometimes I forget I'm listening to headphones with the Chiarra. It has an inherent ability to make the electronics "disappear" and just allows the music to flow over you in waves.
A truly superb sounding amplifier which beats the commercially built amplifiers hands down, both in terms of value for money and sound quality. If the Chiarra was being sold in a Hi-Fi shop (taking the overheads, manufacturing / design costs etc. into account) you'd be looking at a VERY expensive little amp indeed.