The System Fidelity SA-300SE integrated amplifier is currently the range-topper, beneath which are the 250-series amp, tuner and CD player, various loudspeakers (including subwoofers) and a DVD receiver.

Across the board, simple down-to-earth value is emphasised alongside a sound quality which clearly aspires to rival the best that established names in this country (like Cambridge Audio, Rotel, Marantz etc.) can offer.

Straightforward design

External presentation is simple enough, as is the list of features. You get five line inputs and two switchable speaker outputs, plus an active subwoofer output. Some amps have an output marked 'sub' that is in effect a preamp output - a full-bandwidth signal from somewhere after the volume control.

This one, however, is pre-mixed to mono and pre-filtered, the roll off presumably suiting SF's own speakers and subwoofers. That's fine if you're going to use their speakers, but the chance of it accurately matching any given setup from another speaker manufacturer is slim.

The weight of the amp encourages hopes of beefy build and output drive. Indeed, the build is very good, with a steel case and brushed aluminium front panel. Inside the case is a toroidal transformer which is definitely on the generous side for the amp's rated output of 35 watts (8 ohms). There's also quite a lot of fresh air, but the heatsink is a decent size.

Mounted on it are a couple of power integrated circuits, which have provided output drive in two or three models we've seen lately from various sources and, thanks to the employment of these devices, there's relatively little else on the main amplifier board.

Included power supply

Unusually, very unusually at this kind of price, System Fidelity has provided the amp with a regulated power supply. Also, small-signal stages often run off such a supply, so
it's not often employed for power amps.

That's because they are usually designed to have a high 'power supply rejection' (which should, in principle, mean they won't benefit from a regulated supply) and because such supplies inevitably waste power and limit maximum output delivery compared with the unregulated version.

Nevertheless, that's what has been used here and the fairly modest output rating does at least keep the power wastage manageable.

A luxurious amplifier

Mounted against the back panel is the input selector board, which uses relays and passes the signal on to a motorised potentiometer volume control. That, at least, ensures that no real-world input signal will ever cause premature overload. But the volume control itself is a bit of a weakness: it's a cheap-grade part with rather poor mechanical tolerance.

As a result, the tracking between channels isn't brilliant and there's noticeable backlash. In practice, this means that channel balance can vary by enough to skew images a little, depending on which direction one last turned the control and by how much.

Socketry is nothing special, but perfectly adequate. We actually quite liked the dual purpose spring-clip 4mm socket speaker terminals, which have meaty springs and seem to do their job well. As is common these days, the mains switch is at the rear and the front panel control just switches to standby.

This is, of course, to allow switching 'off' by remote control, something which brings us to the best bit: the all-metal remote control. It's pure class and a real touch of luxury.

Mind you, that luxury will be wasted if the sound isn't up to scratch and it's here that we have some reservations about the SA-300SE.

However, we were also very impressed with certain aspects of its performance. It may not be the Philosopher's Stone, but bare us out because its good points are interesting and could prove highly seductive for many.

Punchy bass

What most excited us was the amp's bass.

Its measured bass response is, like most respectable amps these days, ruler-flat to well below the 20Hz cut-off of hearing and, therefore, out of sight better than any loudspeaker its likely to be partnered with.

Despite that similarity, amps often have widely differing subjective bass due to the way in which they control the loudspeaker. Not only the tightness and precision, but also the apparent extension (at low frequencies it can vary significantly) and this is often one of those areas of performance where it does often seem that you get what you pay for.

The SA-300SE doesn't so much stretch that particular envelope as burst out of it. Bass is not just extended, it has a combination of grip, drive and tunefulness that we'd normally expect to see in an amp costing three times as much.

Yes, there's a limit imposed by the fairly modest power rating (one side-effect of regulated power supplies is that there's effectively no dynamic headroom, so 35 watts is pretty much your lot, steady-state or transient), but current delivery is comfortable into four ohms and the amp seems unafraid of the majority of loudspeaker loads we found to test it with.

Short of being asked to burst eardrums at ten paces, it really does give one of the best semblances of real high-end bass that we've come across in a budget amplifier.

Something missing

You'll already be wondering where the 'but' comes in. Essentially, it's in anything that's not bass. Midrange and treble aren't bad, but they never quite seem to have the insight that we've heard from the best sub-£500 amplifiers.

Recent models from Marantz and Creek spring to mind, not to mention the Cambridge Audio Azur 640A. Each offers resolution details that have traditionally been the preserve of the finest kit, details which this amp really can't match.

Although, it's quite hard to put the finger on exactly why, because ostensibly the sound is all there - the basic presentation is clean and tidy and one can easily be impressed. Stereo image depth is not quite all one might wish for, however.

Confirming evidence that there's a strong correlation between this and the resolution of fine detail in the performance of audio electronics.

Worth a listen?

It's quite hard to sum this amplifier up succinctly, but it's clear that it is a frustratingly incomplete performer in sonic terms.

It's certainly worth hearing, if only to discover just what really good bass can be. But its resolution is just not up to the standards we expect in order to give it a full-blooded recommendation.

It's smart and practical, but it sits at a competitive price point and we feel it doesn't quite make as strong a case as some.