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Ashdown Rootmaster RM-500-EVO II 500-watt Bass Head

500-watt Bass Guitar Amplifier Head with 5-band EQ, Overdrive, Compression, Subharmonic Generator, Effects Loop, XLR DI Output, and Headphone Output
$769.99

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Ashdown Rootmaster RM-500-EVO II 500-watt Bass Head
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Full-featured, Lightweight Bass Head

Discerning bass players rely on the Ashdown RM-500-EVO II for reliable tone and rock-solid performance. This 500-watt Rootmaster EVO II series head features a 5-band EQ, overdrive, subharmonic generator, and onboard compression for endless tweaking and tonal flexibility. The RM-500-EVO II is great for gigging and practice alike. Run straight into a soundboard without a DI box, thanks to an XLR output. A rear-panel headphone output makes silent practice easy. Beyond that, you can crank up backing tracks and jam along via a separate input with Line Mix level control. And despite all of these convenient features, the RM-500-EVO II weighs a mere 4.6 pounds!

An EQ built for tone tweakers

Ashdown bass amplifiers are known for their flexible equalizers. The RM-500-EVO II has a 5-band EQ specially voiced for bass guitar, with bands at 1.5kHz and 240Hz to tame growly mids and muddy low end, along with traditional bass, middle, and treble controls for broadband sculpting.

1-knob overdrive, compression, and subharmonics to shape your sound

A flexible EQ is only half of the tone-shaping power the RM-500-EVO II has to offer. Live and studio musicians are sure to appreciate the simple one-knob compressor for adding extra punch and smoothing out leads. A flexible overdrive control dirties up your sound with subtle grit to full-on fuzz. And for floor-shaking bass, you can dial in the RM-500-EVO II's onboard subharmonics generator for an instant boost in low-end resonance.

Ashdown delivers the modern bass sound

With an artist roster that has included Adam Clayton of U2, James Jamerson Jr., and John Entwistle of The Who, Ashdown is responsible for shaping the sound of the modern bass. Ashdown amps serve up punchy dynamics with powerful, controlled lows and modern sheen. Bassists here at Sweetwater like Ashdown amps for their durability to stand up to tour-grade abuse. Check out the RM-500-EVO II for an amp with tones and features that won't let you down on the road or in the studio.

Ashdown RM-500-EVO II Head Features:

  • Compact, lightweight bass amplifier head
  • 5-band EQ for flexible tone shaping
  • 240Hz and 1.5kHz specialty bass bands clean up mud and tame honky midrange
  • Compressor adds punch, smooths out leads
  • Drive control dials in smooth saturation or aggressive fuzz
  • Subharmonic generator adds floor-shaking low resonance
  • Line Mix knob lets you connect and jam along with music
  • FX loop for routing rackmount gear and pedals
  • Rear-panel headphone output with accompanying On/Off switch makes silent practice easy
  • Drive and subharmonic effects can be controlled via optional footswitch (sold separately)
  • Ready to gig with speakON/phono speaker output and XLR DI output
  • Matte anodized alloy front panel for easy visibility under bright stage lighting
  • Weighs a mere 4.6 lbs.

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Tech Specs

  • Type: Solid State
  • Number of Channels: Single channel
  • Total Power: 500W
  • Compression: Yes
  • EQ: 5-band EQ
  • Inputs: 2 x 1/4" (active, passive), 1 x 1/4" (line)
  • Outputs: 2 x SpeakON, 1 x XLR (direct out)
  • Headphones: 1 x 1/8"
  • Effects Loop: Yes
  • Footswitch I/O: 1 x 1/4" (drive, subharmonic generator)
  • Footswitch Included: No
  • Cooling System: Internal Fan, Rear/Side Air Vents
  • Power Source: Standard IEC power supply
  • Height: 3.38"
  • Width: 12.36"
  • Depth: 9.25"
  • Weight: 5.73 lbs.
  • Manufacturer Part Number: RM-500-EVO II

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Customer Reviews

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Rated 5/5

The best I've ever owned or used

I don't ever want to play though anything else for as long as I live - yeah, it's that good. From running it through my GK 210 cab for rehearsal or through my Ashdown Klystron 115 as a monitor for shows or the two together if there's no PA this thing is a BEAST. Buy it now. Do it. What are you waiting for. Disclaimer, if you want crystal clean tone go somewhere else. If you want that curled up on the couch, got the day off of work unexpectedly, it's cold outside and you have a fireplace warmth coupled with the growl of 500 African lions then GET THIS AMP. It is the perfect blend between Fender and Orange, bitey but not jangly or harsh. I love it at any price but for what your paying as long as it lasts the features and tone are incredible.
Music background: Wishful Thinker
Rated 5/5

So light but sounds so heavy!

Always fancies an Ashdown amp and finally took the plunge with a Rootmaster EVO 2 500 watt head. First of all it's just so light that it makes no sense but the days of lugging around my old Ampeg are behind me. Then best of all it just sounds fantastic. Clear but thick and warm just how I like my p bass to sound. The EQ is great very easy to dial in and the FX are useful too, I love to run a bit of drive nearly all the time, really cuts through but fills the low end. If I could award this amp more stars I would! Already saving up for the lightweight matching cabinets.
Music background: Semi pro
Rated 5/5

Mind blowing

Killer amp! Sounds like a tube amp clear and warm but is the lightest head I"ve ever picked up, it"s crazy light but so much tone and power. Love it
Music background: Pro
Rated 4.5/5

Replaced the good old Hartke HA3500

Chinese mada? Yes. But well made.

Tone? YEAH!
Powerful? YES, SIR! Plugged it into a 4x10" and a 1x15" (the full stack) and it was awesome, although I usually play it through a single (but amazing) Fender Rumble 1x12".

It delivers WAY more power when you engage the reasonably good onboard compressor. I know... Many of us (like myself) don't like a comp at the end of the signal chain, but that's not a big deal, since its powerful enough for you to get huge sound of it with your comp pedal.

I used to have a (bulky and heavy, yet reliable) HARTKE HA3500 and the VX410, but the half stack was like 150 pounds!

Now I've got plenty of sound with less than 40 pounds (Rootmster and Rumble 1x12").

PROS: good sound, powerful as hell, really lightweight, amazing looks, good EQ, the VU is really useful.

CONS: drive is lame (although I don't care about it), sub-oct is poor, building is not as good as it could be (a rubber foot was lose at unboxing, but you can easily replace it).

A TIP: get yourself a custom-made bag. I did it and it looks brand new so far, even with tens of gigs and thousands of miles,
Music background: Rock bassist since 2002
Rated 2/5

Gret sound - Horrible craftmanship

Purchased my first NEW bass head after having used equipment for years. Wanted to have a Compressor, Sub Octave and Overdrive in one unit. This amp sounds great. However, the mute button started giving trouble (hum and high pitched piercing sound when engaged), Hi Mids control started to hum and Sub Octave would kick in and out continuously. Maybe a Lemon. Sent for Warranty repairs.
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