USED - Marshall ST20H 20w Guitar Amp Head - valve amp studio JTM (Made in UK)

This used Marshall ST20H 20w Guitar Amp Head is in excellent, like-new condition and has been fully tested. Reviving the classic JTM tone, this compact valve amp delivers the powerful sound Marshall is renowned for, now in a smaller form factor. Part of the Studio series, it provides authentic, smooth valve-driven breakup at manageable volumes, ideal for home or studio environments. Despite its size, the all-valve circuitry produces the iconic blend of crunchy and clean tones that defined a generation and remains instantly recognizable worldwide.

Like the original 30W head, the Studio JTM is loaded with two ECC83 preamp valves, two 5881 power amp valves and one ECC83 phase splitter, taking you right back to the renaissance of rock’n’roll. The Studio JTM offers the same control and versatility as older models, where simply patching the two channels together opens up a world of all-valve tonal possibility. Power switching enables you to switch effortlessly between 20W and 5W and two loudness controls mean you can play as loud as you like. Features such as a DI out and FX loop have been added, bringing the JTM into the now. 

Hand built at our world-class factory in Bletchley, England, the Studio JTM features finger-jointed cabinets, hand-welded chassis, hand-soldered potentiometers and valve bases, and the highest quality componentry. Adorned with period-correct aesthetics from the same metal, red enamel poured “coffin” logo to its fawn fret complete with gold piping and beading, the Studio JTM beautifully nods to the 60s. 

1. Outstanding Marshall sound 

Short: This reissue painstakingly reproduces the legendary, warm, and smooth tone of the original Marshall JTM that inspired generations of musicians. 

Medium: The first JTM amp created the legendary sound that inspired generations of musicians. In honour of that, the Studio JTM brings the iconic tone that sprung Marshall to the forefront of rock’n’roll in the 60s to today. 

Long: Inspired by the first JTM that captured the sound of the 60s, the Studio JTM recreates the vintage tones that so many know and love. An unmistakable sound that is recognised all over the world, the Studio JTM is a loving homage to the amp that responded to the rock’n’roll revolution. From its legendary warm and smooth tone to 

blending the voices for a combination of crunch and clean, the Studio JTM brings the outstanding sound that Marshall is so well known for. 

2. Significantly smaller 

Short: The same iconic JTM sound, but more compact. The Studio JTM packs a punch while taking up less space than the original. 

Medium: Accurately recreating the iconic look seen across thousands of stages over the years, the Studio JTM has the power of a classic Marshall amp in a compact design. Packed with the same vintage tones you know and love, just in a smaller package. 

Long: The smaller scale of the Studio JTM gives players the power of the authentic Marshall tone, in a more compact design. Handmade in the UK just like the original from the 60’s, the Studio JTM is significantly smaller and lighter than its 30W counterpart, making travelling and gigging a breeze. 

3. Full vintage sound for the small stage (Low wattage) 

Short: Swap between 20W and 5W at the flick of a switch and let the era-defining sound of the JTM steal the show, whether it’s playing at home, or on stage. 

Medium: Switch between 20W and 5W at the flick of a switch and let the era-defining sound of the JTM steal the show, whether it’s playing at home, or on stage. The 5W mode allows playing at a lower wattage without compromising on tone. 

Long: The Studio JTM has built-in power reduction technology, enabling players to switch between 20W and 5W. Any guitarist in any environment can achieve the defining sound of the JTM, whether that’s at home or on stage. The iconic Marshall sound you know and love in a much smaller unit built in the UK just like the original 30W counterpart. Whether you’re at home, the studio, or the big stage – the Studio JTM can adapt to bring exceptional tone to any situation. 

4. Handmade in the UK 

Short: Expertly crafted in Bletchley, England, this iconic British-built amp effortlessly captures the Marshall spirit. 

Medium: Handmade in the same UK factory that has been manufacturing Marshall amps since the late 60s, the Studio JTM is built on decades of experience with expert craftsmanship at the very heart. 

Long: Handmade in the Marshall UK factory, the Studio JTM is built with the same expert craftsmanship, in the same factory, that has been manufacturing amps since the late 60’s. Faithfully assembled, the Studio JTM features finger-jointed cabinets, hand-welded chassis, hand-soldered potentiometers and valve bases, and the highest quality componentry. Adorned with period-correct aesthetics from the same distinctively solid metal, red enamel poured “coffin” logo to its fawn fret complete with gold piping and beading, the Studio JTM beautifully nods to the 60s. 

5. Iconic stylings 

Short: Faithfully recreated, the Studio JTM is beautifully crafted with iconic touches that hark back to the 1960s. 

Medium: Adorned with period-correct aesthetics from the same solid metal, red enamel poured ‘coffin’ logo to its fawn fret complete with gold piping and beading, the Studio JTM is a beautiful nod to the 60s. 

Long: Featuring the finest componentry, the Studio JTM is adorned with aesthetics from the 60s, with its fawn fret with gold piping to the iconic solid metal logo with a red enamel font. Jim bought these logos from a funeral hardware store, earning them their affectionate name of ‘coffin’ logos. Less than 50 made their way onto customer facing models, so reintroducing this classic Marshall logo onto the Studio JTM is a nod to where it all began. 

6. Endorsed by the artists you love 

Short: With a rich heritage of over 60 years, the JTM has had a wealth of famous owners, pioneers such as Jimi Hendrix, Angus Young, Joe Bonamassa and Gary Moore. 

Medium: Millions of people around the world have heard the tones of the JTM, made famous by pioneers such as Jimi Hendrix, Angus Young and Gary Moore. It’s your turn to be a part of history with the Studio JTM and its valve-driven break-up at lower volumes – perfect for playing at home or on stage. 

Long: Over 60 years ago, the JTM started it all, creating an iconic sound that changed the game forever. With such a rich heritage it’s no surprise that the JTM had a wealth of famous owners, pioneers such as Jimi Hendrix, Angus Young, Joe Bonamassa and Gary Moore to name a few. Untold millions have heard its tone on stage or in the studio, but now it’s your turn to be a part of history. 

7. Authentic vintage tone 

Short: The Studio JTM is crafted with classic Creamback Celestion speakers, first developed in the mid-sixties. 

Medium: Crafted with Creamback Celestion speakers, the Studio JTM offers that definitive vintage tone. Creamback speakers ensure the Studio JTM delivers on the classic sound for the 60s. 

Long: Ideal for creating that definitive vintage tone, the Studio JTM is equipped with G12M-65 Creamback Celestion speakers. Creamback speakers handle greater power allowing for additional low-end grunt that complements the warm and vocal mid-range crunchy upper. 

8. Jumping channels 

Short: Much like the original JTM, the Studio JTM has the ability to jump channels with a patch cable. 

Medium: The Studio JTM comes with the ability to jump channels with a patch cable. This gives players the ability to mix or blend the high and low voices for a unique sound from the 1960s era of rock and roll. 

Long: Much like the original 30W JTM’s before it, the Studio JTM comes with the ability to blend voices with a patch cable. This gives players a unique blend of heavier tones and bright treble. To access both voices simultaneously a short jumper cable can be run between the two voice inputs. 

9. Added details 

Short: The Studio JTM comes complete with a newly added FX Loop and DI out. 

Medium: The Studio JTM comes with updated features such as an FX Loop and DI out. Both features open new opportunities though adding FX and external recording. 

Long: A new era for JTM. The new Studio JTM comes with updated capabilities for players to take advantage of, such as an FX loop. This allows external effects, such as reverb and delay, to be placed in the ideal position in the signal chain after any added distortion. The Studio JTM also has a new DI output feature, providing players the ease of directly to a recording device or PA system. 

ST20H
Power	20W with power reduction to 5W
Valves	2 x ECC83, 1 x ECC83 (phase splitter) and 2 x 5881
Channels	Single channel with four separate inputsHigh treble and normal loudness controls
Equalisation	Treble, middle, bass andpresence
Speaker outputs	5 x 1/4” jack sockets(16Ω load / 8Ω load / 4Ωload)
Outputs	DI output
Unit weight	9.25kg
Unit width	500mm
Unit height	240mm
Unit depth	230mm