Head-master? Session's latest is a 250 watt mono/stereo head - sounds esoteric? - not so, says Gary Cooper

The purpose behind the Session SG2100 head is blindingly simple - but, like many inspired concepts, it's so obvious once revealed that it seems amazing it hasn't been done before. 'Hang on,' you say; 'I've got a mono guitar, so what use is a stereo amp?' The answer - if you use stereo effects - is, much more than you probably realise.

With a conventional (mono) guitar plugged into the single input, the Session functions as a twin channel 250 watt RMS MOSFET (transistor) powered amp. As with this maker's famed Sessionette combo, the switchable channels (either footswitch, or front panel rocker switch triggered) provide 'Clean' (Channel B) and 'Overdriven' (Channel A) sounds. Use a stereo effects unit, however (say a stereo chorus pedal or rack mounted stereo FX delay/processor) via the single send/twin return sockets on the SG2100's front panel, and the Session turns into a true stereo amp, complete with both normal stereo sounds and a special 'wide' setting - not unlike those found on cassette/radio 'ghetto blasters'. Obviously to get the benefit of this stereo effect you need two speaker enclosures, and some distance between them.

PHYSICAL DETAILS

The Session SG2100 is as individual in appearance as it is in concept. Rather than vinyl clad, it's wrapped in a grey fabric. This may or may not take the wear and tear of plastic (only time will tell), but it does give the amp a distinctive image. Metal caps protect the corners and it stands on four rubber feet. A top-mounted carrying strap is also fitted. Being transistorised, its weight is exceptionally low for such a powerful unit, although in dimensional terms it compares with most 100 watt heads.

FACILITIES

As one has come to expect from Session, this amp has several unique, and very useful, features apart from its stereo role with suitable effects units. The back panel looks simple enough, with a standard IEC mains input, four speaker outputs (two per side - both 0.5 amp fuse protected against faulty connections) plus two labelled Monitor outputs, each of which has its own level control. The apparent purpose of these outputs is to enable the user to send a feed from each of the twin power amps to a suitable slave, the level being controlled by the pot beside each socket. In fact it has a double role (and one that I feel Session should try and find a way of illustrating on the back, if only for the benefit of future, non handbook owning, users). This second use for the monitor sockets is as a stereo source input, and the implications of this are really enormous. Just think about it: you can feed any outboard device (say a rhythm machine, a sequenced synth, even a stereo cassette player with a backing track) straight into these sockets and, using the two level controls, balance the sound against your own playing. I'm sure that there are many other potential uses, but these come immediately to mind as good examples. It's a brilliantly simple yet effective bonus.

The front panel controls begin with a single jack input and run thereafter from right to left. Three rotary knobs control Channel A; Overdrive, Volume and Filter. Filter is an extremely effective passive tone circuit intended to be used with the overdrive sound. It blends in extra high frequencies when turned up (being flat at around 4), and smooths and mellows the overdrive when swung zero-wards. Beneath the first channel's controls is a rocker switch offering 'Eq set/Eq in' positions. Switched In, the three main rotary tone controls function normally, while Out delivers a pre-set tone, although this can be varied to some extent by using the aforementioned Filter. Providing this preset sound is an ingenious way of avoiding the cost of fitting individual tone controls per channel. It allows you to set up one sound on the clean channel, using the tone pots, but to have a completely different sound (albeit largely fixed) when you switch to the overdrive channel. Without this provision (as with most amps) you'd be forced to use the same tone settings on both channels. I'll discuss how well it works later.

Completing the control section, there's a rocker switch for manual either/both channel selection next to the Eq set switch, beside which is a DIN footswitch socket. Three tone controls (treble, middle and bass) come next, followed by a depth control for the on-board Accutronics springline reverb. A single effects send and two returns (all 1/4" jacks) plus an illuminated mains rocker complete the picture, with just one final rocker switch to come, the Stereo/Wide control.

THE TRIAL

Knowing how well the Sessionette does one of the hardest jobs going (delivering superlative overdrive from low powered guitars), I dug out my ancient (and feebly pickupped) Fender Jag for my first run on the SG2100. Would it perform as well as its thrice-honoured ancestor?

Step one was to set a clean sound on Channel B. The tone controls work beautifully, delivering an impressive range without the nasal artificiality which characterises some modern amps. I rapidly achieved a sharp-edged cut, not unlike a Tele's, as a basic rhythm tone. Next came the acid test - distortion. Silent switching selected Channel A. Here, I certainly didn't want the razor-slice that I had on Channel B, so I flicked on the Eq Set (defeating the rotary tone controls) and found the basic tonality for that barely-controlled overdrive which has made the Session name so big in such a short time. It's hard to describe this pre-set tone, but if you imagine a good, thick lead sound (not easy to get with a Jag, believe me!) with the highs rolled off a degree, the middle boosted and the low bass cut, then that's about as close as I can get to describing it. Preset it may be, but once you've wound in the overdrive effect (stage two of setting your distortion) you can make significant changes by using the filter control. As a result, even the limp-wristed Jag took of and flew, and that's something which I can only get from the rarest of amps. The three effects together, the pre-set Eq, Overdrive and Filter adjustment, combine to enable even the meanest output run into screaming overdrive - it's fabulous!

Changing the Jag for my Tokai/Seymour Duncan pickupped 'S***t', the pre-set worked even better. The filter winds down to shape the overdrive to a creamy mellowness (not usually the sort of sound you'd expect to get from a Strat), or alternatively it can give you an instant bald patch by axeing the top off your toupe with outrageous treble. I was going to say that, if anything, the Session was a bit too toppy, but (having been loaned a prototype) I checked back with Session, who told me that they'd already had similar feedback and have endowed production models with extra bass response.

In passing, I also mentioned that the reverb could have been a bit heftier. Guess what? They'd already figured (and fixed) that too.

Moving over to my Gibson SG, once again the Session sounded superb. Clean, it was capable of both warmth and attack, and the overload approaches a heavy Rock soloist's ideal. Controllable Gibson-sweet distortion, with tameable feedback as you approach terminal breakup, is a feature of only the finest transistor amps - most merely run into a messy, harsh, jumble of chaotic discords. In this most telling condition the SG2100's performance is close to a good valve amp.

If that particular question is raised (is its overload as good as a valve amp's?) my answer must be, it all depends on what you mean. Soundwise the Session's overdrive is astonishingly close. You have to take a little trouble to get your settings right; after all, you have pre/post gain, filter and overdrive to juggle with, but with both Fenders and Gibsons it can get so close that only the very pernickitiest ears could tell. Where the solid state circuitry does show, however, is in a lack of 'touch sensitivity' - the dynamic response to right hand picking attack which I've only ever obtained from valves. Some players will notice this, others won't, so you'll just have to try this aspect for yourself.

Moving on, with a good stereo chorus or other stereo effect the stereo sound is truly delicious. As long as you can separate your speakers, the chorus swirl runs across between the two cabs, giving a remarkable depth and emphasis to the effect. Good stereo delays work wonderfully, too. I've recently been trying MTR's Madrack (a review follows soon) which has a pre-settable stereo auto-pan/delay. Run through the Session it's astounding, sounds bouncing across the audio 'stage' in a mind-boggling way. There's undoubtedly vast potential in stereo, and most guitarists (myself included) are missing out on it. With its 150 watt a side power, the SG2100's stereo role has to be tried to be believed.

CONCLUSIONS

There are four factors which, to me, make this amp a welcome arrival. The first is the range of facilities (especially the 'reversible role' feature on the monitor outputs). The second is a clean sound which positively tingles - especially with Fenders. It's particularly fine for Country, Country/Rock and similar styles. The third plus is the Session's distortion. Again, it works beautifully with Fenders and must have massive gain, as even the emasculated Jag pickups had it roaring for perfect H.M. solos. What it would sound like with a Kramer, I hate to think! In praising the Session's abilities with Fenders, incidentally, I'm not damning it for Gibson owners. It's more that, generally speaking, Gibsons are much better at delivering well overdriven Rock solo sounds. Fenders can sometimes prove tricky, but the SG2100 can turn even the weediest output into massive overload. Add these three virtues to the massive potential for exploiting stereo effects and the SG2100 head is self-evidently great buy. It's not too expensive, either, at RRP £295 - especially when you consider the massive 250 watt mono (125w per side stereo) output. I think it's going to be another winner for Session.

RRP £295 Inc. VAT

More details from distributors Musimex, (Contact Details)