Arc 5

GUI:

Bearing in mind that this is a 'macro-knob concept-synth' from top to bottom I think the GUI has been wonderfully realized. It's immediately intuitive, boldly colour coded, and logically laid out. The great waveform/oscilloscope display is nifty eye-candy!
However, the GUI is TINY, and that, along with the slight faux iPhone-like glass reflection, may give the wrong impression that this is just a gimmick synth.

Some aspects could be improved:

• although eminently intuitive, it is necessary to read the manual for some aspects which are not immediately apparent, such as 'what analog waveform is this?' 'Where is the flanger?' 'Where is the bitcrusher?' etc. Just twisting knobs will only get you so far...
• the signal path chain at the bottom of the GUI is very small. Larger buttons would balance it out nicely.
• when switching any signal (or layer) component off, the dials go black/blank. It would be much better if the parameter settings were just grayed-out and still visible so we could see how the component is set up, even though switched off. This would be particularly useful regarding the effects section.
• the arpeggiator page shows steps 1-16, but with a little GUI resizing it would be possible to see steps 1-32 without the need for paging up/down .
• I find it counter-intuitive that the synth-type selector is configured like a dial, so in order to select the bottom synth-type you have to click-drag the mouse upwards. In my opinion direct-clicking on the synth-type name to select it would make so much more sense.
• I have the same quibble with the effects on/off switch. In this case the switch isn't even necessary as it's possible to switch the FX on and off via the signal chain diagram at the bottom of the GUI.
• the menu font could be larger and more contemporary. It seems quite out of place on such a stylish synth. The preset 'next' and 'previous' arrows would benefit from this too.

Sound:
In a word, SUPERB! Lovely Virus-like basses and 303s, warm supersaws, thunky FM chaos, koto-like waveguide sounds which with just a few knob turns can morph into breathy ethnic flutes. The effects on this synth alone are excellent. Again, warmth is the quality that most comes to mind. Amazing woody overdrive/distortion, 'that' 80s chorus pedal sound, tempo-synced delay and flanger from 8 bars up to 128th notes, and smooth reverb. Nothing overly hyped, just all good solid algorithmic warmth. Love it.

Features:
5 synth types embedded in a pseudo 2-oscillator parallel-path architecture, each with its own arp. Huge value for money! As I've mentioned elsewhere on this site, Arc 5 is almost like a mood-synth. Load it onto a track, and it has something to offer no matter what you're in the mood for.
A standalone version is included too.

Docs:
Very comprehensive User Guide with diagrams that clearly explain how the macro-knob concept has been implemented. The first 5 - 10 pages tell you all you really need to know, the rest is there just for the sake of completeness. Only about 25 sparse pages in all. Short and sweet.

Presets:
Excellent! Designed to be a 'player's synth', it certainly offers the goods for many styles of electronic music. Trance-gated supersaws, chip-style bitcrushed FM arps, percussive analog thuds and blips. Certainly inspiring and the perfect companion for a song-writer who isn't that much into sound design, but likes some tweakability on hand too. Intuitive MIDI cc control assignment too.

Support:
Excellent responsive and enthusiastic devs, keen on receiving input from their users, and quick to fix bugs, and implement do-able features. If they continue to expand their product line with the same devotion and enthusiasm shown for Arc 5, then I can only imagine them becoming a force to be reckoned with :) .

VFM:
Arc 5 isn't for everyone, but it has heaps on offer, and may be more than enough for some.

Stability:
A couple of teething problems still present in v2.1. Cubase 6 crashed while deleting a clip while A5 was playing in another section of the song. Had to restart the computer. :(
The CPU usage is still very high. On my stock Q9400 (Intel Quadcore) I battle to have more than 5 instances playing simultaneously in Cubase 6... 4 seems to be the magic number. With NI Massive I can use way more instances, probably up to 8 or more in Ultra quality mode, and my CPU meter doesn't complain too much at all.

Overall:
Amazing sounding synth, competes very well with the big boys soundwise. AI is certainly a company to watch.
Pity about the CPU usage and stability issues, because I'd like to be able to plonk Arc 5 on at least a few tracks in every project. It's that good. If AI can sort out these issues, Arc 5 may become a songwriter's first point of call.

Summary:
A resounding 7/10. There are some crucial issues in stability and performance that count against Arc 5. GUI opinions are subjective, but that knocks a little off the total too. I hope the devs view my rating as an encouragement, and that they're definitely onto something very good here, it just needs some polish and tightening up before it's a perfect 10.