Review: Marshall ST20C Studio JTM 20W Combo

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Review: Marshall ST20C Studio JTM 20W Combo

Marshall ST20C
Words by Lewis Noke Edwards

Marshall ST20C | Electric Factory | RRP $2399

The Marshall ST20C is a newcomer in the growing Studio range from Marshall, re-issung their classic designs. Marshall have been building amps for the stars since the 60s. Characterised by sizzling, bright and crunchy tones, Jim Marshall’s shop in London gained a following because of the sheer volume they were capable of, particularly with players like Pete Townshend of The Who. While there’s a myriad of revised models available, with increasing amounts of gain for more modern music, the classic designs have remained a mainstay, constantly some of the best sellers because of the hugely influential recordings and performances they’ve been involved in amplifying.

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Because of this, Marshall has reissued one of the classics: the JTM. The JTM(Jim & Terry Marshall)45(RMS wattage). The JTM45 prototypes were demo’d by Pete Townshend and Deep Purple’s Ritchie Blackmore, working through six prototypes before agreeing on a design. The JTM45 was originally built as a combo, the sheer power of the amplifier prompted Marshall to split it into a head and cabinet situation, the new range honouring both of these designs.

Marshall ST20C Review

The ST20C is a 20W combo, also being available in a head-only version, the ST20H, as well as matching cabinets also being on offer. Switchable to 5W for lower-volume practice, while also having a DI-output for recording and use with an impulse response.

The ST20C is a single-channel amplifier, though has four inputs for varying types of input stage, split into two high sensitivity and two low sensitivity inputs. From here there’s two Loudness controls to adjust the two sets of inputs, three-band EQ and a Presence control. The simple control layout provides a great foundation for a stellar tone, while some amongst us are excited at the prospect of daisy-chaining the inputs for more gain.

ST20C Power

Finally, Marshall’s ST20C has a low/high switch to toggle between 5W and 20W, being set to ‘Standby’ when in the middle position. Lower power allows you to drive the tubes of the amplifier harder, without having to push your amplifier beyond reasonable or usable levels. It’s all good and well to push your amplifier in an isolated studio environment, but if recording live with a band, performing live even just practising, ear-splitting volume will seep through neighbour’s walls, bleeding into drum mics and ruining otherwise usable takes! The power control available on the Studio Series alleviates this issue, allowing you to push your tubes to break up while retaining a convenient volume.

ST20C Sound

In use, the ST20C is that classic Marshall tone. Inherently British, often replicated but never quite equalled, the JTM is bright, forward and gritty, allowing for clarity and space in your tone. The simple EQ controls offer a wide range of sounds, shifting your tone from a dark, mid-forward tone to a crisp, bright jangle without any harshness, mess or mud.

Scooped mids offer a classic metal tone, harnessing the tone from early Judas Priest and Iron Maiden , especially when paired with a humbucker. Dialling the mids back in gives classic rock, ranging from British pioneers Led Zeppelin, Cream and Hendrix who made sure he had Marshalls after spending time in the UK. More modern jangle and indie sleaze is available when you push the treble, your tone cutting in a percussive manner, without becoming too harsh or jarring, while still managing to cut through a dense, fast arrangement.

The Presence control makes your tone bigger, occupying more space without simply adding mud or low end, it’s something magical happening harmonically. Your tone is weightier, offering heft and clarity in the unique combination that only a Marshall can. The beauty of the Marshall ST20C is that that’s it. Everything sounds good, with simple controls to refine it.

Jumper patch cables in the additional inputs create additional grit and drive, retaining the clarity or the base tone of the amp. The power switch allows you to push it all harder, harnessing the ECC83 preamp tubes and 5881 power amp tubes to their full potential, without killing the relationship with your neighbours, or allowing more controlled recording of that great tube tone.

Marshall ST20C 2

Marshall JTM ST20C Overview

The Marshall ST20C is a 20W combo amplifier, sitting comfortably in the middle of the range between the head-only version, the Marshall ST20H and a few cabinets available. It builds on the back of the original Marshall tone, designed in conjunction with some classic British rock heavyweights.

It’s a tried and true design, redefined with modern tech allowing you to push the tubes to breakup, a task usually ear-splittingly difficult with even 50-watt heads, let alone 100-watt. The ST20C is 20-watts, records well, while also having power controls to dial back for jamming, rehearsing or studio work at reasonable levels.

The Studio range as a whole honours Marshall’s legacy, history and impact on the musical landscape as we know it, the ST20C specifically speaking to an amp that bore Jim Marshall’s own name as his business began in the early 60s. Demanded on stages around the world, toured and relied on for recording for decades, Marshall Amplification has been the go-to, their designs now famous the world over would have largely been impossible if it weren’t for the trailblazing JTM45 design, re-issued now in the Marshall ST20C.

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