Ashdown Guitar Magnifier AGM-484H Head review

Designed and built in England, the compact AGM-484H is a 30-watt all-valve head specialising in classic British amp sounds

  • £999
Ashdown AGM-484H
(Image: © Future)

MusicRadar Verdict

Portable, compact, but adequately powered to deliver all-valve tones on stage, the AGM-484H is a triumph of British amp engineering at a very attractive price.


  • +

    Classic range of British amp sounds.

  • +

    Footswitchable boost and two clipping modes.

  • +

    Compact and relatively lightweight for an all-valve head.

  • +

    An exceptional pedalboard platform.

  • +

    Good value and great build.


  • -

    No off-switch for the fan.

MusicRadar's got your back Our team of expert musicians and producers spends hours testing products to help you choose the best music-making gear for you. Find out more about how we test.

Ashdown Guitar Magnifier AGM-484H Head: What is it?

For a brand that made its bones applying low-end theories to bass amps, Ashdown has made launched quite the charm offensive for guitar players’ affections in recent times. 

At the vanguard of this is Dave Green, the good Dr Green whose electrical engineering nous was behind the eponymous Dr Green pedals, and more recently on such pedalboard treats the Pro-Fx range, which in the Retro Drive and Two-Band Boost offer guitar players some very impressive effects at more than fair prices.

And then there’s the AGM series. Designed in Essex, affordable, stylish, and with some superb tones, the AGM or Ashdown Guitar Magnifier series has already impressed us with its Class A combo, the Ashdown AGM-5C. At five-watts, switchable to one, the AGM-5C offered a sparkling range of British tube amp tones at volumes suitable for the home. 

Ashdown AGM-484H head

(Image credit: Future / Olly Curtis)

The AGM-484H has much of the same DNA beyond the shared black-and-gold aesthetic. But it was designed for a quite different application, with 30-watts of portable valve power positioning it as a solution for the gigging guitarist.

The AGM-484H is still quite a weight. This is not like picking up Fender Tone Master Twin and amazing onlookers by how strong you look; 10kg is what Ashdown declares at. But it ships with a heavy-duty leather strap handle, and underneath the hood you’ve got a lot going on that justifies the load, with four JJ 12AX7 preamp valves and further four JJ EL84s in the power section.

There is plenty of ventilation to keep it cool. On the rear of the amp, there is a cooling fan that is on whenever the amp is on. As for your sounds, the AGM-484H is a single-channel affair with a switchable boost that has a dedicated gain and master volume. 

Ashdown AGM-484H head

(Image credit: Future / Olly Curtis)

You can activate the boost via the toggle switch on the control panel or via footswitch, so in a sense the AGM-484 gives you one-and-a-half channels to play with. There’s another toggle switch to changing the clipping, and thus the character of the gain, while the main amp’s controls number Gain, Bass, Middle, Treble, Presence and Volume. 

The effects loop’s 1/4” connections are mounted on the front panel, immediately adjacent to the trademark VU meter, with the footswitch input is joined by a pair of speaker outputs on the back of the amp.

Ashdown AGM-484H head

(Image credit: Future / Olly Curtis)

Ashdown Guitar Magnifier AGM-484H Head: Performance and verdict

There’s no mistaking the British accent on the AGM-484H’s voice, calling to mind the usual suspects dressed in diamond-pattern grille cloth, not to mention a whiff of the NMV Marshall. And yet, it is something of a blank slate. The AGM-5C worked gangbusters with pedals, and this is is no different.

Also consider...

Ashdown AGM-5C

(Image credit: Future / Olly Curtis)

Ashdown AGM-5C
From the same Guitar Magnifier series, this Class A combo is similarly voiced, similarly great value, and, at 5-watts with onboard power scaling, it is ideal for the home or studio.

Victory VC35 The Copper
Victory's VC35 The Copper has an incredible tone and response, and surely would give many high-end boutique amps a run for their money.

Victory V4 'The Duchess' Head
Ample headroom, clean tones sweetened by an incredible valve-driven preamp, reverb and tremolo for adding space and movement to your tone, the Duchess has it all in one little box.

The clean tones are wonderful. Refrain from the boost and you will be rewarded with a tones that can handle a wide range of styles, from immaculately rendered notes for jazz and funk, to that trebly British Invasion-style chime. 

When you turn the amp on, the noise from the fan is gentle but noticeable. There’s no off switch, so it might annoy you when recording, but as an amp for the stage – or indeed one that is voiced to crank – this is hardly a deal-breaker. Once you dial up the volume, that whirr disappears. 

The EQ is very flattering, with Presence always useful should your guitar’s pickups be voiced a little too dark. Dial-in more gain and crank it up and it’ll go to the edge of breakup. 

It’s when you engage the boost that the AGM-484H shows its hand. The boost and mainline gain stages interact nicely and open up great swathes of tonal opportunity, from that sparkly grit that can make a blues lead come alive to a searing hard-rock lead guitar. There are plenty of sweet spots along the way.

Flick the clipping toggle if you need to call order to proceedings; this will tighten things up in the low end, and you’ll get more harmonic effervescence. 

There is more than enough output to rock the Dog & Duck, and really, that is when it shines; cranked up, pushed hard, using your guitar’s volume control to pull back the gain on command. That’s the sort of truly dynamic response that only a tube amp can deliver. 

MusicRadar verdict: Portable, compact, but adequately powered to deliver all-valve tones on stage, the AGM-484H is a triumph of British amp engineering at a very attractive price.

Ashdown Guitar Magnifier AGM-484H Head: The web says

“As live music makes a tentative return, so does the need for amplification that delivers great tone at proper gig volume levels. Ashdown’s AGM-484H is an ideal choice for the working guitar player, with compact dimensions that make it easy to transport and fit on the smallest of stages.”

Ashdown Guitar Magnifier AGM-484H Head: Hands-on demos



Ashdown Guitar Magnifier AGM-484H Head: Specifications

  • PRICE: £999
  • TYPE: Valve preamp and valve power amp
  • OUTPUT: 30W
  • VALVES: 4x 12AX7, 4x EL84
  • DIMENSIONS: 80 (h) x 400 (w) x 220mm (d)
  • WEIGHT (kg/lb): 12/26
  • CABINET: Steel
  • CHANNELS: 1, with footswitchable boost
  • CONTROLS: Boost, gain, bass, mid, treble, presence, volume, boost volume. Boost on/off switch, clip switch
  • FOOTSWITCH: Single-button latching footswitch toggles boost function, not supplied
  • ADDITIONAL FEATURES: Series effects loop, footswitchable boost
  • OPTIONS: None
  • RANGE OPTIONS: Ashdown’s Guitar Magnifier collection includes: AGM-5C combo (£749), AGM-30 Offset head (£1,099), 45W AGM-684C combo (£1,599) and 15W AGM-284C combo (£999). Matching speaker cabinets include the AGM-112 featured here (£349), AGM-210 and AGM-212 (both £599)
  • CONTACT: Ashdown Engineering

MusicRadar is the number one website for music-makers of all kinds, be they guitarists, drummers, keyboard players, DJs or producers...

  • GEAR: We help musicians find the best gear with top-ranking gear round-ups and high-quality, authoritative reviews by a wide team of highly experienced experts.
  • TIPS: We also provide tuition, from bite-sized tips to advanced work-outs and guidance from recognised musicians and stars.
  • STARS: We talk to musicians and stars about their creative processes, and the nuts and bolts of their gear and technique. We give fans an insight into the craft of music-making that no other music website can.