SR amps have been steadily gaining a reputation for both their quality of sound and their solid construction. Made in Italy, rumour has it at the “other end” of a highly respected and well known manufacturer’s factory, the Jam 100 is the basic model in SR’s Jam series. A rectangular box constructed in birch plywood with a metal grill, it is at 11kg a remarkably lightweight unit that is very easy to move around due to its deep recessed handholds.

Our test unit came in a very stylish natural wood finish, rather than the alternative black moquette or black matt. Carrying a two way biamp with a six-inch woofer and a compression tweeter, it is extraordinarily small and compact for its power output of 100 watts. Having a top mounted control panel means that all the functions are easily accessed and apart from being visually appealing, the layout is clear and uncluttered and the “white on black” makes it easier to see the controls when you really need to. Channels 1 and 2 offer two XLR balanced mic inputs along with two ¼-inch jack unbalanced inputs. Channel 3 has Hi and Low unbalanced inputs, while Channel 4 has unbalanced line inputs with RCA connectors. Channel 5 is the Master section with its balanced direct Line Out. There is also a record out with RCA connectors connected to a record out volume control, phanthom power on/off switch for powering condenser mics and an internal reverb effect control. Each channel has a set of EQ controls which include High, Med and Low settings together with EFF (reverb) and volume. There is also a master volume and a master EFF control. To the rear of the unit is the mains socket, on-off switch and gnd lift.

The Jam 100 is one of the quietest amps we have ever tested – there is no discernible hiss or noise and it delivers a very clean and natural sound with no obvious colouration. The overriding sonic characteristic is one of richness and warmth and dialling in the unit’s internal reverb adds a depth and width to the sound that puts the SR at the top run of acoustic amplifiers. And then there’s that balanced XLR Master output, allowing you to plug it into a more powerful system while you control the mix – what could be better!

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Valve amps hold a hallowed place in the lexicon of guitar amplification. So when a brand new model comes on to the market we naturally want to check it out. The HGTA-40 is a typical combo configuration with a line of controls along the top of the front panel above a traditional woven grill outlined with cream piping with the mains line and various connections to the rear. A strong leather carrying strap is secured to the top panel, while the (relatively heavy) unit sits on four solid, circular nylon feet. Fitted with three ECC83 valves and two EL43s and loaded with a Celestion Vintage 30 G12 speaker, the HGTA comes with two channels, one dedicated ‘clean’ channel with volume control, bass, treble and EQ controls, while the other is a drive channel which is split into two sub-channels. These two subchannels each have a gain control with channel 2 being a lower gain than channel 3. However, the controls are cascaded so the gain from channel 3 starts from wherever channel 2 is set. The shared EQ controls comprise contour, bass, middle, treble, overall reverb and masters 2 and 3 which are set in sync with the gain controls 2 and 3. The rear panel features speaker jacks and a two way footswitch for channel selection. There is also a buffered effects loop and two recording out jacks.

Plugging in the house GS1 with its single Seymour Duncan ‘Seth Lover’ humbucker, you immediately realise the potential of the HGTA. The Celestion Vintage 30 G12 delivers tones that are sweet and smooth with a depth and width to the sound that is pure valve territory – creamy, rich and full bodied. Adding reverb to the mix evokes the golden age of the valve combo and the amazing Belton’s Digilog unit provides a controlled and refined reverb that adds yet another extra dimension to this extraordinary sonic palette. Having the Master channels 2 and 3 in sync with the Gain channels 2 and 3 offers all manner of overdriven options that will keep you well and truly rooted to the blues. While following the clean route will take you someway into the sonic sensibilities of Burrell and Farlow. Realistically priced just shy of £500, this is an amp that you should plug into and play. You’ll be amazed.

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There’s been a lot of positive Tweeting over the past few months about this neat little 12” combo from the American ZT company that measures just 14” X 15” X 9.25”. Coming hot on the heels of ZT’s mighty little blaster the Lunchbox that packs a powerful, but beautifully clean punch into a pint pot, the Club with its 12” speaker moves to bring some depth and warmth to the proceedings.

Like the Lunchbox, separation and clarity is, as our transatlantic friends would say – awesome. There’s stacks of headroom and with an output of an average sustainable 200 watts coupled with a fully customised speaker driver, you won’t be surprised to learn that it’s clean right the way through. That’s not to say however that you can’t get some interesting tonal variations – tweek the gain and treble settings and the Club will really roar. But the great thing about this baby is that even when you push it towards overdrive mode, it still retains that rich, warm tone.

The top panel controls are recessed into the cab and each comes with a solid knurled nylon knob, with reverb, treble, bass, volume and gain joining a 1/4” jack input. The rear panel offers a 1/4” plug in connection for headphone/ line out , a switch between the internal and external speaker, a 115V or 230V option, a power switch and a plug in cord connection – which on our sample was slightly loose - mental note: make sure you push home fully.

Coming in at 10kg, it’s a little heavier than its lighter weight stablemates and it doesn’t yet come with a rain/dust jacket. But it does fill a much needed gap in the marketplace for a manageable, sweet sounding amp that is as much at home in a club – as its name suggests, as it is in a large concert hall.

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Among the many lightweight but powerful micro bass amps on the market today one that really stands out from the crowd is US company Genz Benz’s Shuttle 6.0 bass amp. Weighing a measly 3.75lbs it’s the middle child of a trio of pint-sized powerhouses (there’s a 3.0 and a 9.0 too, yes that’s 900watts) this straightforward looking box has a simple control layout with gain, tube presence, mid tone/cut-boost/bass/ treble all present and correct. The secret to the Shuttle 6.0’s incredible power-to-weight ratio success is its clever blend of analogue and digital technology that produces a subtle mix of tube warmth with amazing punch and power.

The signal path utilises a 12AX7 tube preamp and Genz Benz’s acclaimed Active EQ and responsive Signal Shape circuitry, which can be controlled via an optional foot switch, plus there’s a signal mute button and three signal shaping circuits that include low boost, mid cut and high frequency attack. Using leading-edge high power Class D amp module, the Shuttle 6.0 can deliver 375watts at 8 ohms and over 600watts at 4 ohms. Completing this compelling package is the unique Shuttle “saddle” that slots the amp into one or two equally lightweight 12” speaker cabinets that are capable of impressively warm sounds at any volume. 

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This amplifier is extraordinary. A possible 200 watts emanates from a 165mm specially designed, customised speaker encased in a snazzy brushed steel and polished, coated MDF cabinet measuring just 4.4” x 7.3” x 9.8”! And if that doesn’t grab you, get this: it weighs in at a ridiculously light 9.5 lbs. Designed in California by a group of audio scientists, who also happen to be musicians, the ZT team started out with what they call “a clean slate”. That is to say, while they didn’t totally disregard conventional amplifier design, neither did they take it as gospel. They applied their sophisticated technical understanding in this surprisingly complex audio field to re-write some of the “rules” whilst still working within the more traditional methodology. The question is, have they, as they put it, “cracked the code”.

The Lunchbox is certainly a beautifully simple little amp to use. Behind the solid polymer handle on the top panel is a row of recessed controls which includes an input jack and a powerful on/off red neon. The controls feature solid knurled knobs adjusting the ambience, tone, volume and gain. Whereas the latter three are a pretty conventional set of amplifier controls, it is the ambience control that is the most intriguing. ZT tell us that they have been able to create this subtle effect that mimics the natural short term reflections produced from the rear of an open – back amp/cabinet by expanding the proprietary technology used in the signal chain. All very technical! But what it does in reality, is to allow the player to dial in luscious levels of depth, width and fullness to the sound. And what a sound! The Lunchbox has a remarkably clear and clean tone, with a very open and direct response. Even when working at high volumes this little monster loses none of its integrity, delivering the same quality of sound reproduction across its full range.

Coming with a voltage selector, a speaker on/off switch, a speaker out jack, auxillary and headphone inputs – the latter with a volume control, I reckon that the Lunchbox is set to become one of the all time “classics”. For more go to

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