Comparing valve-based amps to transistor-based amp is like comparing vinyl to the compact disc -- both have their strengths, and a preference is subjective. TLA Audio's Fatman brand produces valve-based amps, backed up by years of experience building for professional recording studios.
The iTube 452 is its latest and greatest product, aimed at iPod users and audiophiles alike. It'll cost you £1,500.
Art can only be art if it serves no function but to exist. For this reason, the iTube 452 could justifiably be categorised as art if it ever broke internally. It's a beautiful piece of kit, precisely constructed with tank-like solidity. And at around 25kg it's one of the heaviest amps we've ever held.
The super-hot valves that drive the system reside behind a solid metal grille, both to protect them from knocks and to prevent you from burns.
A total of nine valves drive the 452, and four line-level inputs allow for way more than just iPods to be connected with the bundled 'ValveDock'.
The ValveDock's retro styling will appeal to many, no doubt, but we don't feel its construction adequately mirrors that of the main amp, mainly due to its light weight and relatively hollow feel.
This mains-powered ValveDock outputs audio via gold-plated RCA connections, and will output video via composite or S-Video cables. It's compatible with most iPods except the iPhone (both original and 3G), and we successfully outputted video to a TV from an iPod classic and fifth-gen iPod video with excellent results.
The amp itself is a push-pull system. These offer greater power efficiency in comparison to single-ended systems, with the only downside being that they typically produce a small element of distortion as a result of their electrical design. This is inaudible, however. Note that a single-ended system of equivalent power would easily be twice as expensive.
Fatman's iTube 452 derives its '452' moniker from having two 45W output channels, but will also output to a subwoofer via RCA cable. To the rear are superb, heavy-duty wire terminals, with impedance outputs of 4 Ohms or 8 Ohms to assist power matching with speakers.
As a performer, the 452 boasts a seductive, rich voice, proving once again that, while cumbersome, delicate and back-breakingly heavy, valves do offer a sonic difference over modern transistor amps.
But don't get us wrong -- we're not part of the crowd that claims the introduction of the transistor was fundamentally detrimental to the shape and sound of music.
The Fatman genuinely offers a beautifully smooth and warm sound quality, however. It sings with an excellent, tight low end and shimmering highs, balanced with a natural mid-range, gearing it ideally towards reproducing the human voice.
Eva Cassidy's 2008 posthumous release Somewhere was particularly enjoyable, as were recordings ranging from Jeanne Newhall and Alison Krauss to KT Tunstall and Dire Straits.
High volume didn't seem to be an issue either, with some terrific live performances from Dashboard Confessional still free of distortion at close to maximum output.
This didn't remain the case, however, during high-volume sessions of Pendulum's second album In Silico -- a heavily electronic, ultra-synthesised drum 'n' bass recording. We felt this was a genre best left to transistor-based amps, which with their razor-sharp sound quality can better deliver such intense synthetic performances. That said, lighter electronic music such as rap and R 'n' B sounded great.
Naturally, if using an iPod, you should be using Apple's Lossless encoder, or at least 256Kbps MP3s or AAC files. But there's a larger stumbling block in terms of sound quality that we were not expecting: the Fatman's separate ValveDock. The difference in sound quality between using the iPod's headphone socket and using the ValveDock is subtle, but noticeable. With the ValveDock you lose some of the smoothness of the mid-range, making it slightly imbalanced and muddy.
This issue is no reason to be put off, as the vast majority of the money you're spending is going towards the amp. But we advise that you use the ValveDock to simply power the iPod and use a high-quality 3.5mm-to-RCA lead to transmit audio from its headphone socket. Better still, get hold of Arcam's superb rDock -- probably the only audiophile-grade, integrated pre-amp-equipped iPod dock on the market. Our testing showed it's a stunning match with the iTube 452.
Valve-based amps may always be less preferable to comparable solid-state amps as a result of their size, weight and fragility. But the benefits are obvious if engineered well, and Fatman's iTube 452 is just such a system.
If you solely enjoy your electronic and dance music, give it a miss. But if you adore the musical worlds of vocals, classical, acoustic, jazz, soul, folk and even rock, this is a terrific performer, and testament to the sonic advantages valves can offer.Edited by Nick Hide