Blackstar St James 50 EL34 Combo review

Blackstar claims its latest release is “the lightest 50-watt all-valve combo in the world”. Is this really the future for tube amplification? Time to plug in

Blackstar St James EL34 Combo
(Image: © Future / Olly Curtis)

Guitar World Verdict

For professional players and serious amateurs who are after a compact and portable all-valve combo that doesn’t compromise on tone, the St James is a superb choice.


  • +

    Compact and very portable.

  • +

    USA-inspired clean channel.

  • +

    Superb vintage overdrive channel.

  • +

    Cab Rig goes beyond standard IRs.

  • +

    Power to spare for live gigs.

  • +

    Superb loudspeaker.


  • -

    No hardware output level control for Cab Rig outputs.

  • -

    No offline mode in the Architect app.

  • -

    Somewhat pricey.

You can trust Guitar World Our expert reviewers spend hours testing and comparing guitar products so you can choose the best for you. Find out more about how we test.

Blackstar’s history goes back to 2004, when a gang of four guitar-playing mates left secure employment with a major amplification manufacturer to spend the next two and a half years developing their own range of guitar amps, from the somewhat more dubious security of a shed in Northampton.

Blackstar Amplification made its debut in 2007 at Frankfurt’s Musikmesse trade show – and the rest we know. Today, it’s one of the top amplification brands in every niche, from hand-wired pure valve designs to cost-effective digital modelling, all presented with the typically down-to-earth pragmatic attitude that’s a reflection of the company founders and the city Blackstar comes from. 

So perhaps it’s apt that Blackstar chose to pay tribute to its hometown with one of its most important launches yet: the St James range.

St James is the Northampton district that’s home to the Saints Rugby Union Premiership club and the skyline-dominating National Lift Tower, and the St James amplifiers have a lot to live up to – and that’s before we peer inside the design – as Blackstar is proudly calling them “the future of valve amplification”.

Blackstar St James EL34 Combo

(Image credit: Future / Olly Curtis)

There are actually two different flavours on offer within the range, both available in combo and head format, one being a high-gain 6L6-powered circuit aimed at modern rock and metal, while the one we’re looking at here is the lower-gain, pedal-friendly EL34 version.

The St James amps are billed as the lightest 50-watt tube amps in the world, with a number of innovations making that possible, the most obvious being the lack of heavy mains transformer. Instead, we have a patent-pending switched-mode power supply piggybacked on the top of the main chassis, which is carefully folded for improved rigidity.

Inside, miniature SMD components cohabit with heavy duty power resistors and capacitors on high-quality printed circuit boards. There are separate PCBs for the front and rear controls, the valve bases and a smaller board for Blackstar’s Cab Rig digital speaker emulation, all securely supported and joined by ribbon cables, terminated with robust Molex connectors.

Blackstar St James EL34 Combo

(Image credit: Future / Olly Curtis)

There are a few cool features. In the middle of the main board there’s a reactive load device, which mimics the loudspeaker’s response for realistic silent recording. LED indicators next to the preset pots for output valve bias and balance take away the guesswork, although high voltages and the complex nature of the St James’s layout mean bias adjustment is best left to the pros – it’s not really a DIY task. 

Tucked away inside the candlenut plywood semi-closed back enclosure is a single Celestion Zephyr 12-inch loudspeaker, a lightweight driver that’s exclusive to Blackstar and marries the cone characteristics of the legendary Vintage 30 with a unique hi-tech ferrite (not neodymium) motor.

The St James is a two-channel design, featuring a high-headroom USA-flavoured clean channel that’s teamed with a low-to-medium gain overdrive channel based on classic early 60s British designs. There’s a volume control for the clean channel, and volume and gain controls for the overdrive channel, with a level control for the digital reverb and an overall master volume.

Behind the three EQ knobs, you’ll find dual-gang potentiometers controlling separate circuits for both channels. 

The clean channel EQ is a regular passive array, while the overdrive channel has passive interactive bass and treble controls with an active midrange that operates independently from the bass and treble, cutting or boosting frequencies. The overdrive channel also includes a footswitchable boost, with an alternative toggle switch on the control panel.

Another toggle switch changes channels, while a third gives you a choice of power output settings, with a studio-friendly two-watt option or a full-on 50 watts for stage use. In between there’s a third choice called Sag, which is 50 watts but with a modified dynamic response to imitate a power supply being driven hard.

Rear-panel options (which point downward because of the top-facing control panel) include a series effects loop with switchable levels and a choice of extension loudspeaker sockets.

There’s also a balanced XLR and TRS jack/headphones output for the St James’s integrated reactive load and Cab Rig speaker emulation, together with a USB socket for uploading Cab Rig presets and direct recording. A three-way switch accesses three onboard Cab Rig presets, with a practically infinite range of choices from Blackstar’s Architect app ready to edit and upload.

Overall, the St James looks the business, and boasts typically robust build quality, plus cool ’60s-inspired boutique features including radiogram-style control knobs and an illuminated logo.

Blackstar St James EL34 Combo

(Image credit: Future / Olly Curtis)

Feel & Sounds

We tried out the St James combo with a variety of guitars, including our regular Fender Stratocaster and a fabulous borrowed 1972 Les Paul Custom, with the original embossed-cover pickups. As well as a studio audition, we used the St James for two gigs, including a three-hour ‘Saturday night special’ at a very busy town pub.

With the premium TAD Redbase EL34s warmed up, there’s practically no background noise, partly due to the lack of a conventional mains transformer. Both the Les Paul and the Strat were dialled in within seconds, and while the St James sounds great with single coils, it really comes alive with the mid-rich tones of the Les Paul’s humbuckers. 

The black-panel influenced clean channel has the sweet treble and scooped mids needed to get that buttery ‘both pickups on’ rhythm tone, while the drive channel sits somewhere between JTM45 and AC30 and can be coaxed in either direction for truly stunning classic rock and blues sounds. 

Blackstar St James EL34 Combo

(Image credit: Future / Olly Curtis)

The drive channel is very touch-sensitive, cleaning up if you back off a little, or barking like a Doberman if you hit the strings hard. Activating the drive channel’s boost function adds a healthy 10dB of gain. However, Strat owners with low-ish output pickups might find themselves wishing for a couple of decibels more.

The digital reverb adds a cool ambience that can be as subtle or forward as you like, while the Cab Rig simulated speaker outputs deliver authentic mic’d up sounds direct into a desk for studio or live use. 

There’s a choice of three presets on the amp, meanwhile the Architect partner software gives you a practically infinite choice of combinations, which can be uploaded to the St James or saved and stored offline.

Blackstar St James EL34 Combo

(Image credit: Future / Olly Curtis)

We like the Architect app’s clean, minimalist page design, which includes a live bias status display for the St James’s output valves. At the moment, the app only works when it’s connected to an amp, which may be a slight annoyance for some as it stops you from browsing features, for which you don’t always need an amp hooked up.

The St James handled our live gigs with ease sat next to a large enthusiastically played drum kit that one felt as well as heard. There was plenty of power to spare, with the master volume staying well below the halfway mark. We also used the Sag power amp setting, which adds a subtle but effective dynamic compression to the output; single notes and chords breathe and bloom a little more.

In the studio the two-watt setting is perfect and you can combine real microphones with the Cab Rig virtual mic’d environments for extra versatility. Turning the standby switch to ‘off’ disconnects the loudspeaker. However, the entire amp signal is still routed through the St James’s reactive load and the Cab Rig emulation, making the Blackstar ideal for quiet stage environments as well as loud ones.


Blackstar is calling the St James the future of valve guitar amplification, and while that’s somewhat reliant on the uncertain future of valves, there are significant innovations underneath that smart fawn vinyl covering. The sounds are superb, nailing British ’70s classic rock tones and ideal for pedal users, while the low-noise floor, built-in reactive load and Cab Rig emulation make it a perfect partner for recording and quiet gigs.

Indeed, there were a few moments while testing it with our ’72 Les Paul Custom when the guitar felt as though it might weigh more than the amp!

Super-portable guitar amplification is very popular right now, with all kinds of solutions vying for your cash. However, the St James stands out with 50 watts of full-on valve power in a 1x12-inch enclosure that weighs about the same as a typical 20-watt solid-state practice combo. Indeed, there were a few moments while testing it with our ’72 Les Paul Custom when the guitar felt as though it might weigh more than the amp!

While the St James isn’t the cheapest all-valve offering out there, you get what you pay for – and the weight saving alone will be a serious temptation for many of us. We reckon it’s great value for money. For professional players and serious amateurs who are after a compact and portable all-valve combo that doesn’t compromise on tone, it’s a superb choice.

Blackstar St James EL34 Combo

(Image credit: Future / Olly Curtis)


  • PRICE: $1,299 / £1,099
  • ORIGIN: Designed in UK, made under licence in China
  • TYPE: Valve preamp, valve power amp
  • OUTPUT: 50W RMS, switchable to 2W with silent recording option
  • VALVES: 2x 12AX7, 2x EL34
  • DIMENSIONS: 535 (w) x 259 (d) x 462mm (h)
  • WEIGHT (kg/lb): 12.8/28
  • CABINET: Lightweight plywood
  • LOUDSPEAKERS: 1x 12” Celestion G12Z-70 Zephyr
  • CONTROLS: Volume 1, Gain 2, Volume 2, bass, middle (active cut/boost), treble, reverb level, master volume, channel switch, Channel 2 boost switch, 50-watt/Sag/2W power switch
  • FOOTSWITCH: FS-19 footswitch (supplied) toggles channels, boost on Channel 2
  • ADDITIONAL FEATURES: Series effects loop, digital reverb, integrated Cab Rig cabinet simulation with mono balanced XLR and stereo TRS line/headphones outputs, integrated reactive load, USB audio/Cab Rig editing
  • OPTIONS: None
  • RANGE OPTIONS: EL34 head (£1,199 / £999); high-gain ‘modern preamp’ St James 6L6 combo ($1,299 / £1,099) and head (£1,199 / £999). Zephyr-loaded 2x12 cabs ($749 / £499)
  • CONTACT: Blackstar Amplification

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Nick Guppy

Nick Guppy has been a regular contributor to Guitarist magazine for over 20 years, mostly writing reviews on guitar amps and related products. He built his first valve amplifier at the age of 12 and has since bought, sold and restored many more, with a particular interest in Vox, Selmer, Orange and tweed-era Fenders, alongside Riveras and Mark Series Boogies. When wielding a guitar instead of soldering iron, he’s enjoyed a diverse musical career playing all over the UK, including occasional stints with theatre groups, orchestras and big bands as well as power trios and tributes. His favourite musical genres are ‘anything that’s good’.