Icon Audio Stereo 60 Mk 3 - £1,700

Icon Audio Stereo 60 Mk 3 More powerful than most and built the old-fashioned way: no printed circuit boards here!

Icon’s exuberant literature makes many claims for this amp, including higher output power than most KT88 models can muster: 65-watt ultralinear or 35-watt triode. There’s nothing outrageous about that, though, and indeed we’ve seen 100-watt amps using just a pair of KT88s.

The relatively high output power is partly responsible for the considerable weight of this amp, but the chassis is very substantially built too, complete with a solid copper top-plate around the valve area. Unusually, all the valves are octal-base types, including the small-signal valves and voltage regulator. These are relatively old designs, compared with the ‘modern’ (about 1960!) KT88.

We weren’t surprised, given the valve complement, to find that internal electronic assembly is entirely point-to-point, with the only circuit board being a small one for the remote control decoder. Passive components are good quality throughout, including one-watt-rated resistors almost everywhere, brand-name polypropylene capacitors and a motorised volume control.

The input selector switch is manual (not remote-controllable) and connected to the input sockets with PTFE-insulated screened wire. The complement of inputs looks a bit stingy, but don’t forget that the ‘Source/tape’ switch effectively gives you a fourth input.

Sound quality

In many ways, this more than any of the others in the group, upheld the classic stereotype of ‘valve sound’, with strong, very present vocals, good vitality and persuasive communication in all sorts of music.

If there is a quality to this amp that may cause dissatisfaction it’s tonal coloration. This clearly isn’t a function of frequency response which is fine, rather it’s something about the distortion ‘fingerprint’ of the amp that is pesistently audible and can be a little distracting. One listener pointed to cymbals as being the main indicator of this and indeed it is the region where high midrange becomes treble that shows it up most.

We’d probably live with it happily enough, though, considering the Stereo 60’s many admirable traits. Notably, and perhaps to some people’s surprise from a valve amp, it has very good timing and gets feet tapping reliably across the widest range of musical styles. It’s also very good at resolving detail and, for instance, our musically dense opera excerpt benefitted no end from the way this amp keeps all the different parts clear and well-balanced. Bass is a little mixed, with good extension but sometimes a slightly soft attack, at least compared with the very tight leading edges this amp produces on high-frequency notes.

On the other hand; the bass is well integrated with the rest of the range. Dynamics are very good, swinging effortlessly from one extreme to the other and also making the most of finer gradations around the middle of the range.

LIKE: Good timing, with lovely integration of instruments
DISLIKE: Slight lack of naturalness to treble-rich sounds
WE SAY: An energetic amp that offers high power and delivers it with confidence

Origin: UK
Weight: 27kg
Dimensions: (WxHxD) 440x230x400mm
• 4 line inputs
• Record output
• High/low sensitivity
• Triode/ultralinear mode
• 8/4 ohm speaker outputs
• Notional output 65W/35W
Distributor: Icon Audio
Telephone: 0116 244 0593
Website: iconaudio.com