A winning combination of sonic virtues with vices that are so minor, most users will probably never be aware of them. Truly, one of the best integrated amps of which we're currently aware
Detail and musicality are both highly developed in this understated amplifier, but don't let its calm manners put you off guard for more dramatic moments
Some may find the degree of control excessive
Can seem a touch polite at times
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The A38 is a vital part of the Arcam FMJ range which, in our opinion and from an ergonomic point of view, is still the tops when it comes to hi-fi choice!
The informative display, traditionally straight-forward control of basic functions and general layout are excellent. If we wanted to be really fussy, we'd request slightly bigger text on the buttons in recognition of the more myopic user.
But, it's what's under the hood that really interests us. Just to recap, an integrated amplifier is basically a power amp and a preamp in a single case (the preamp may, of course, be little more than a selector switch and volume control). The power section in the A38 is quite similar to that of the A32, while the pre is derived from Arcam's C31 standalone preamp.
As reviewed, the preamp section is line-only, though a phono stage is available as a welcome factory-fitted option.
Conceptually, the preamp section is little more than a selector and volume control, though it does have some gain and offers a few extra features. It doesn't have the tone controls of the old A32, but it does preserve balance control and input level trims.
These are built in at no extra cost in terms of sound quality, since the volume control is an electronic attenuator and, thanks to the microprocessor that controls everything, balance and trim are achieved simply by adjusting the settings.
This is the kind of thing where electronic control adds undoubted benefits - three mechanical controls (input trim, volume, balance) in series is no-one's recipe for reliable high-quality sound!
We were intrigued to find a little piece of what looks like ferrite glued on to the volume control chip. Damping material on chips is common enough, but we haven't seen this one before; presumably it provides some degree of magnetic screening, while the resilient glue that's been used will also contribute to mechanical damping.
There's more conventional squishy plastic stuck to the input selector relays which handle main source switching (the issue of which switching device to use - mechanical, relay or electronic - is one of the many vexed questions facing designers).
But good-quality sealed reed relays, like those used here, are probably near ideal for their combination of good sound, high overload level, reliability and near-silent operation.
Inside Arcam's amp
Before the signal even gets to those relays it's buffered by separate op-amps for each input, making the amp particularly easy for source components to drive - although not many these days are short of output 'oomph'.
Then, having been selected and boosted (attenuated) to the right level, it leaves the preamp board on short jumper wires that connect to the physically separate power amp section.
A rear-panel switch selects integrated or power-amp mode (allowing for future upgrades with a separate preamp) and passes the signal to a discrete-transistor circuit that ends up with a pair per channel of Sanken output transistors, carefully configured to minimise thermal modulation effects.
There's been a lot of discussion about thermal effects in amplifiers. On the whole, however, most amps are not affected by temperature change, but there are some whose performance varies quite noticeably as the output transistors heat up. This is inevitable, even when bolted to a substantial heatsink like the one in the A38.
Sure enough, performance here seems to be consistent, whether it's just started playing music or well warmed-up by several minutes of loud rock'n'roll.
Throughout the A38, Arcam's construction and component selection steers a careful course between fussy and cost-effective.
Most components are surface-mounted and the circuit boards are quite complex multi-layer affairs, but connectors, for instance, are nothing fancy and there are no 'brand name' passive components. Despite that, the capacitors and, perhaps, the most important component in any amplifier - the mains transformer - is of a good quality.
Volume control steps can be set to 2dB, 1dB or 0.5dB, to suit your own tastes in precision versus convenience. Arcam also supplies the A38 with a new remote control (the CR90), which is a universal device capable of controlling practically everything - always assuming you can be bothered to follow the necessary steps to set it up. After all, anything that can reduce the proliferation of remotes in the average household is welcome!
One of the most common questions put to the us is: "how does my old high-end gear compare to mid-price up-to-date equipment"?
It's not always straightforward to answer with audio technology's moderate progression, so it was, therefore, fascinating to be able to compare this amp with a well-regarded pre/power combination from the late 1980s that was on hand around after a recent service. Said combo cost considerably more than £1,200 in its day, never mind inflation.
But despite a lively and energetic sound it lost out to the A38 on resolution, imaging, grip and, in the end, general musicality.
Of course, what matters in the here and now is how the A38 stacks up against current competition, but that little experience did bolster our confidence in regarding the present suspect as a very fine amplifier in general terms.
It has a highly neutral tonal character, clear and naturally presented detail, excellent manners and very little in the way of 'grain' or other unwanted artefacts that could cloud one's enjoyment of the music.
The £1,000-odd amplifier market is quite a hotbed of activity these days, with stalwarts like Arcam contending against various Chinese imports, recent start-ups and even upmarket offerings from the big names of domestic audio and AV.
We've come to expect good things from most of these amplifiers, but we found ourselves, over a particularly long review period, becoming unusually fond of the A38. It does all the basic hi-fi things it should, but what really hit home was the extent of the 'more!' factor it contributed to the various systems we assembled around it.
This must be, in a large part, due to the tight, but unfussy control the amp exerts over the speakers. Among the various models we had a chance to test it with were Bowers & Wilkins' superb 803S speakers.
While that might not seem the most obvious pairing, we felt the A38 was not out of its depth in such illustrious company. Not only is the bass taut and rhythmic, but the midrange and treble are very well controlled and highly detailed. Some may find it slightly too controlled, but experience suggests you can't satisfy all tastes in this area, however hard you try.
And to be honest, we're highly enthusiastic about the precision and resolution benefits that 'control' brings in its wake. Stereo imaging is excellent too, with very clear lateral placing and separation and some of the best depth portrayal you'll find on the sensible side of £3,000 or so.
Arcam's fine build quality
All told, we're very impressed with this amplifier. It is both analytical and musical in an impressively large measure.
Its output power is generous and willingly delivered, while the fine build quality, thoughtfully specified feature set and smart exterior only add to its already attractive value.
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