
Small, evil, patient, suddenly alive – it strikes when you do. Same power and feel as a real valve amp, without the glass, heat or weight. Touch the strings and it breathes. Stop – and the snake waits, coiled and ready. It follows you – the Master!
It’s called King Cobra for a reason. Quiet, patient, and suddenly alive – it strikes when you do. This isn’t another little amp pretending to sound big. It actually runs on the same high voltage/power as real valve amplifiers, reacts the same way, but skips the glass, the heat and the headaches. What’s left is just the playing – pure and direct.
Touch the strings and it breathes. Hit harder and it pushes back. Stop – and the snake slips back into silence, waiting, coiled, ready to strike again the moment you are. That’s the idea – an amplifier that feels alive, not obedient.
At Himmelstrutz Elektro Art, our amplifiers are not about reinventing sound, but about evolving design. We hold onto the timeless tones and organic feel of valve amplifiers while introducing new philosophies that prioritise craftsmanship and reliability.
The goal is to preserve that rich, natural sound you crave, but with a modern approach that improves performance and usability. We carefully design and handcraft each amplifier, blending classic warmth with cutting-edge engineering to deliver an authentic, dynamic experience without unnecessary complexity. Our amplifiers don’t just sound like the revered valve amps – they also have the feel. What we provide is a balance of tradition and progression, proving big sound no longer needs big weight.
That singing piano bloom when a note opens up starts with real voltage swing – real headroom. King Cobra holds the same alive feel as the classics, only tuned for what comes next.
That piano-like bloom when a note opens up comes from real voltage swing and headroom – when the circuit can move instead of flattening out. Think of higher voltage the way engine people think of a longer stroke – the piston travels farther, builds more real pull, and responds with a different kind of authority. That’s what higher headroom feels like in an amp – more space for the note to form, bend and bloom before anything chokes it.
King Cobra carries the same expressive swing and give-and-take we love in great valve amps, but delivers it through a stable, discrete design with no glass, no heat and no waiting – that damned 30 to 48 seconds warm-up! Touch it lightly and it whispers immediately; dig in and it pushes back with the same classic movement.
Others talk about valve behaviour. King Cobra just lives it – the movement, the honesty, the bloom – only lighter, tougher and ready to go anywhere.
Compact, strong, and ready for any cab or pedal setup. Reverb or echo in front or loop – both work, just different attitude.
Forget categories. King Cobra isn’t a head, and it isn’t a combo. It’s its own thing – compact, strong, and ready for whatever speaker or setup you like.
Drop it on your cab, keep it beside your pedals, even fit it on a pedalboard if you want.
Time effects, like reverb and echo, can go in front or through the serial loop. Both ways work beautifully, just with different attitude – one melts, the other stays clear.
Gain, Lo, Hi, Vol set the voice and power; Pres. tames/adds top shimmer; Core shifts the power feel – 20/50/100 W, triode↔pentode.
1 – Use Gain, Lo, Hi and Vol to shape the voice. Lo and Hi stay independent, each doing its job without muddy overlap.
2 – Flip the Pres. (3-way mini-switch) to add or smooth the important shimmer.
3 – Core (3-way mini-switch) goes even deeper. It changes the amp’s character itself. Flip the switch and you’ll feel it: the response and compression shift like moving from a 20-watt to a 100-watt valve amp – or think triode to pentode – soft sag, tight punch, or full roar.
4 – Send & Return (serial loop): plug in delay/reverb here for the cleanest result. Put them before the amp for more blend and grit. Both ways work – different feel.
You’ll find all this faster by playing & joyfully adjusting than by being here reading numbers!
British bite, American depth – both and beyond. Clean tones shimmer, driven tones growl. Pedals blend right in – Himmelstrutz or not.
King Cobra moves through a huge span of tone – effortlessly. From shimmering clean to raw drive, it stays open, dynamic, and alive all the way. The Gain control doesn’t just add gain/overdrive or level; together with Lo, Hi and Vol it shapes how the amp breathes. Add the two mini switches – Core and Presence – and the character itself shifts: from gentle sag to tight punch, from soft bloom to glassy attack. Every setting finds its own groove, never losing touch or depth. There’s no dead zone, only smooth transition and response that follows your playing instead of forcing it.
King Cobra doesn’t choose between British or American – it speaks both languages, and things in between. It’s got the mid-focus and bite you’d expect from the Isles, but with the wider low end and openness of the West.
Together they become something broader, quicker, and fully touch-sensitive – a living, breathing animal that follows your hand instead of biting it.
Clean notes shimmer; driven tones grind without losing clarity. Pedals drop in like they belong – Himmelstrutz or not – because the foundation is already musical.
Clean to mean isn’t one stage — it’s the whole chain waking up. Preamp clarity, phase inverter swing, power-section push. King Cobra carries that same living reaction, with a touch of Balthazar magic.
People praise preamps and argue about power tubes, but the real feel often wakes up in the phase inverter — where the signal splits, the attack softens just enough, and the tone starts to move.
Push a real speaker and the system breathes: the cone moves air, the room answers back, your ears add their own compression. That’s when an amp feels bigger than its size.
King Cobra builds that motion in — the phase-split backbone, the push-pull balance, the subtle sway that makes a small amp feel alive. No glass, no excess heat — just the movement.
All that feel, small enough to disappear into your pocket.
So… does King Cobra actually have a phase inverter, even without valves?
Of course it does. A proper phase-splitting heart — driving the signal both ways like it should. No bottles glowing. Same clean-to-mean backbone.
Clean, mean, and everything between doesn’t come from one stage – it’s the whole chain waking up. Preamp shimmer, phase inverter bounce, power-feel movement. King Cobra has that same reaction built in, with a touch of Balthazar magic.
People talk preamps, some swear by power tubes, but the feel often wakes up in the phase inverter (PI) – where the attack loosens its shoulders and the tone starts to sway a little.
Turn up a real speaker and the whole thing gets a touch wilder – the cone breathing, the air answering back, your ears adding their own soft compression. It feels bigger than it is, in the best possible way.
King Cobra carries that same movement – the PI glow, the preamp nerve, the little wobble that makes a great amp (so very small in this case) feel alive, just without the glass, heat or weight.
All that feel, in something small enough to disappear into your pocket.
Use 1 or 2 microphones to record King Cobra through a cab or go direct through Himmelstrutz RECO. Same feel, same honesty, quiet neighbours.
Play King Cobra through your favourite cabinet and mic it old-school – or plug into a Himmelstrutz RECO reactive load for direct recording. Either way, the tone stays honest, the touch stays alive, and your neighbours stay impressed and quiet in the background – as they should.
Recording shouldn’t slow you down. With RECO you just plug in, twist real knobs, and play – the sound sits right without endless tweaking. No apps, no menus, no waiting – just pure analog workflow that keeps up with your ideas.

Valves are great — they’ve shaped guitar tone for decades. King Cobra keeps the response and high-voltage feel, but removes the fragility. Same intent. Smarter execution.
Valve amplifiers earned their place. The interaction, the compression, the way they respond to touch — that foundation matters.
But design doesn’t have to freeze in time. King Cobra keeps the voltage architecture and dynamic behaviour, while eliminating glass, excess heat and mechanical weakness.
Not a rejection of tradition. A continuation of it — built with today’s tools.
Guitar players value history. That’s fair. But progress happens when someone refines the idea instead of copying it.
We looked for the trade-offs. Found the feel. Left the baggage behind.
Valves defined the response — compression, push, honesty under your fingers. King Cobra keeps that behaviour, without the weight, fragility or warm-up time.
No heavy transformers. No glass bottles. Just high voltage and immediate reaction.
It’s not a reinvention. It’s refinement.
444 grams. Internal voltage: 333V. Small format. Full authority.
| JACKS | |
| Input | Front: 6.3 mm TRS instrument input (guitar or bass). |
| Speaker (≥4 Ω) | Rear: 6.3 mm TRS speaker output. Note: 50 W @ 4 Ω. Higher impedances reduce output power. |
| FX Loop | Rear: Serial effects loop, post-preamp / pre-power amp. |
| 24 V DC | Rear: Dedicated 24 V DC / 60 W PSU. |
| PREAMP & POWER AMP | |
| Preamp | Fully discrete Class-A, approx. 333 V internal. |
| Power Amp | 50 W custom Himmelstrutz MOSFET power stage. |
| CONTROLS | |
| Gain | Clean headroom → harmonically rich overdrive. |
| Lo | Low-frequency shaping. |
| Hi | High-frequency shaping. |
| Vol | Master output / power-amp drive. |
| SWITCHES | |
| Presence | 3-way upper-mid / high-frequency response. |
| Core | 3-way fundamental voicing and feel. |
| DIMENSIONS & BUILD | |
| Dimensions | 111.6 × 60 × 61.6 mm |
| Weight | Approx. 450 g |
| Build | Designed, made & assembled in Sweden |
A watt is a watt is a watt, but…
… the perception of loudness is something else. Valve amps often sound bigger than their numbers because they’re not as clean as you might think: even at modest levels they add a natural mix of harmonics and gentle compression that makes notes bloom and carry. When pushed, they round off instead of breaking, focusing energy where the ear is most sensitive. That’s why 30 “valve watts” can feel like 100.
King Cobra works the same way – no valves, no modeling, just pure analog craft. Its high-voltage, fully discrete transistor design recreates that harmonic richness, smooth compression, and touch-driven response – only tougher, quieter, and more consistent.
The result: real valve loudness and feel – without the valves. The same philosophy runs through the entire Himmelstrutz lineup – each amplifier built around the same discrete, touch-dynamic approach, tuned per model to deliver that honest loudness and feel.
Still, King Cobra plays in its own league – running on roughly six times the voltage of its siblings. Does that make it six times better? That, dear player, only you can decide.
Built to order – by hand, by one man. Tested by ear. No shortcuts. Just instruments that live, breathe and inspire.
Every Himmelstrutz product is built to order – one at a time, by hand, by one man. Each unit is tested, tuned, and trusted by ear – by the same man. No shortcuts. No mass production. Just instruments made to last, sound alive, and inspire every time you switch them on.
King Cobra was born from that same stubborn idea: that the old feel of real voltage and real response shouldn’t disappear just because the world moved on.
In 2025, most gear chases convenience, numbers, or digital emulation. Himmelstrutz – together with King Cobra – chases usability, simplicity, and emotion: the sound that moves when you move, breathes when you play softer, and roars when you dig in. A reminder that progress doesn’t have to mean plastic or code – it can mean evolution built by hand, with ears, voltage, and intent.
Handmade today. Ready for tomorrow.
Rock n' roll!

| Compact fly-rigs | 444 g, carry-on friendly, replaces a traditional amplifier head. |
| Session work | Immediate power-up, repeatable response, identical feel across takes. |
| Touring & rentals | Consistent touch and output regardless of venue, cabinet or backline. |
| Pedal-based rigs | Neutral front end with real headroom; drives, fuzz and time-based FX translate correctly. |
| Studio production | Real amplifier dynamics without volume constraints; mic a cabinet or record silently via RECO. |
| Clean headroom | Clean tones remain stable and open even at higher volume settings; ample headroom before breakup. |
| Low-volume operation | Delivers usable, musical overdrive and dynamic response even at restrained sound levels. |
| Volume-knob control | Cleans up linearly without thinning or loss of authority. |
| Maintenance-free systems | No warm-up, no drift, no consumables; stable behaviour day to day. |
| Modern analogue workflows | Real-time circuit behaviour without menus, presets or firmware layers. |
| Single-amp solutions | Covers clean, edge and driven sounds with consistent dynamics. |