1985 BOSS HM-2 Heavy Metal

Model Description:

Every once in a while, there are significant musical genre milestones and, occasionally, there is a singular unintentional contributor to that evolutionary jump. The BOSS HM‑2 Heavy Metal distortion pedal is one such example. The HM‑2 was introduced to an unsuspecting public in 1983, originally manufactured in Japan until production moved to Taiwan in 1988. It was discontinued in 1991 to be replaced by the BOSS MT‑2 Metal Zone in 1992 and the BOSS HM‑3 Hyper Metal in 1993. However, it is the original Japanese HM‑2 that has acquired a devoted cult following over the years by spawning the distinctive ‘buzz saw’ guitar distortion that was the cornerstone of Swedish Death Metal sonic mayhem. The oft‑cited benchmark recording was the ‘Swedeath’ metal band Entombed and their debut album, ‘Left Hand Path’ (1990). The convention dictates that all controls are set to max and fed into an already distorting (often solid state) amp. So, what started out as just another attempt by BOSS to emulate Marshall valve amp tones for the 1980s hair metal brigade became transformed into the definition of an entire music genre, initially kindled in Stockholm and then Gothenburg, Sweden. The HM‑2 Heavy Metal’s influence rapidly spread across the globe and to other heavy metal genres, including grindcore, hardcore and djent. What was once an obscure also‑ran pedal became a must‑have heavy metal rock icon to match its dark, brooding, ominous aesthetic. For tech heads, the asymmetric clipping of the HM‑2 is similar to that of the more well-mannered BOSS SD‑1 Super Over Drive. While the ‘Dist’ control is pretty ineffective for most of its range, it is the low and high ‘Color Mix’ EQ controls that are tuned at key frequencies in such a way as to give it its distinctive extreme mid‑scooped sound with jagged cutting odd‑order harmonics. You won’t find any 400‑800hz mid frequency controls here. The original circuit of the HM‑2 has been much imitated by many other pedal makers over the years due to its unique reputation. Due to demand for vintage pedals, BOSS is rumoured to be reissuing the HM‑2 as an upmarket Waza Craft model in the 2020s. With its enduring, almost mythical, cult classic status, the price of original Japanese BOSS HM‑2s on the vintage effect market is overwhelmingly disproportionate to its modest roots. Those unaware of the HM‑2 Heavy Metal’s massive influence may well not even know about it. Their loss!

Pedal Description:

A devilishly fiendish excursion to the dark side here at CRAVE Guitars. Witness the creator of the legendary ‘buzz saw’ tone, as popularised by chthonian Swedish Death Metal bands like Entombed, Carnage, Dismember and At The Gates. It is ironic that it was ‘discovered’ at just around the time it had been discontinued. This 1985 BOSS HM‑2 Heavy Metal is one mean mother… of a menacing monster. Just look at it! All threatening black and dangerous orange. The Heavy Metal is just insane as well as being a belligerent design statement. Treat it right and it will release the hounds of hell on you. Enough with the deliberately over‑the‑top hyperbole. This HM‑2 came to CRAVE Guitars from its original owner of several decades. The familiar BOSS template houses a distortion circuit that veers more towards transistor‑like sibilant fuzziness than heavy valve‑like overdrive/distortion. Let’s be honest, the only real way to use it is to dime the controls and go for it. Savage it is, subtle it most definitely ain’t! It is probably most at home with a guitar equipped with hotly wound or active humbuckers. A weedy single coil put through an HM‑2 into a lean clean amp really isn’t going to cut the mustard. Used as unintended, tone‑wise, we are in seriously sinister, gritty, grinding heavy metal territory here. Great for that crushing down‑tuned, palm‑muted ‘chugga, chugga’ onslaught. At other, more sensible, settings it is what it is, a so‑so distortion pedal that is good but not particularly unique or notable. Let’s be clear it does not sound remotely like a cracked valve amp but it does sound truly mental. This example has been carefully used over its life with a few minor paint chips but is otherwise all‑original and in great condition. It also comes with its original box and instruction manual which is always a plus. Not only that, it arrived with the first edition of the ‘BOSS Pocket Dictionary Vol. 1’ dated October 1984. Neat. So… the HM‑2. Cool? Nope. Demonically stone cold dead! Rare? Not if you know where to look – in the shady catacombs of the underworld. Collectable? Hell yeah – the prince of darkness will suck out your primitive soul in a heartbeat for one. Take notice and be deeply, deeply disturbed!


  • Made in Japan by Roland Corporation in February 1985
  • The ‘Level’ knob controls the amount of boost added to the signal
  • The ‘Color Mix L’ knob controls the level of bass cut or boost in the distorted signal, centred around 100hz
  • The ‘Color Mix H’ knob controls the level of treble cut or boost in the distorted signal, centred around 1khz
  • The ‘Dist’ knob controls the amount of distortion added to the signal
  • BOSS treadle footswitch turns the effect on and off
  • Red LED ‘Check’ light to indicate when the effect is in use
  • Standard ¼” input and output mono jack sockets
  • 12V DC (BOSS ACA) power supply input or 9V battery
  • Black ‘Made in Japan’ label on the base of the pedal
  • Dimensions: 70mm (w) x 125mm (d) x 55mm (h)
  • Weight: 400g
  • Original box, instruction manual and ‘BOSS Pocket Dictionary Vol. 1’
  • Serial number: 519500 (February 1985)


  • Uffe Cederlund (Nihilist/Entombed)
  • The Chemical Brothers
  • Bilinda Butcher (My Bloody Valentine)
  • Jerry Garcia (Grateful Dead)
  • David Gilmour (Pink Floyd)
  • Richard Hawley
  • Alex Hellid (Nihilist/Entombed)
  • Johnny Marr (The Smiths)
  • Lee Ranaldo (Sonic Youth)

Detail Gallery:

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