MESA/Boogie Royal Atlantic RA-100 100-watt Amplifier Head

MESA/Boogie Royal Atlantic RA-100 100-watt Amplifier Head


The Royal Atlantic RA-100 wears an undeniable crown in the TransAtlantic fleet for delivering all this Tone with a big power gut-punch and three amazing Modes of footswitchable performance. Packing 100 watts of EL34 Brit-voiced attitude, this Atlantic takes everything you love about both Fullerton and Liverpool’s amplifier heritage and brings it all together with rich, chest-thumping high gain in the way only a MESA can.


The Royal Atlantic RA-100’s two channels house the three distinctively different footswitchable modes. Each mode is dedicated to a region of musically-useful gain and is capable of truly iconic sounds. These are comprised of CLEAN, LO and HI and they cover the continents with soulfulness, conviction and authority…you need but plot the course and the Royal will take you there.



Availability: In stock
  • Specifications
  • Features
  • Videos
Amp Type Tube
Chassis Material Aluminum
Rectifier Type Silicon Diodes
Rectifier Tubes n/a
Variac Power Switch n/a
Preamp Tubes 6x Mesa 12AX7, 1x Mesa 12AT7
Power Amp Tubes 4x Mesa EL-34 (or 6L6)
Bias Switch for Alternate Power Tubes Types Bias Select for EL-34 or 6L6
Maintenance Free Fixed Bias Yes
Wattage(s) Quick Reference 3 to 100 Watts via 50/100 Watt Global Power Switch and Mesa's Proprietary Multi-Soak™, Channel Assignable Power Attenuator - See Power Amp Details for more information
Built-In Power Amp Attenuation Built-in Mesa Multi-Soak™ Channel Assignable Power Attenuator - See Power Amp Details for more information
Power Amp Details (Class & Wattage) Class A/B Power with Mesa's proprietary Multi-Soak™ Channel Assignable Power Attenuator that provides each Channel Mode with a 5-position power attenuation switch (-16db, -12db, -8db, -4db & 0db) for Scalable Power Ratings ranging from 3 Watts to 100 Watts
Convection or Fan Cooling Fan Cooled with High/Low Speed Switch
Number of Footswitchable Channels (or Modes) Two Channels with 3 Footswitchable Modes
Number of Style Modes Three
Number of Style Modes Per Channel Ch. 1 = One / Ch. 2 = Two
Types of Style Modes Per Channel Ch. 1 = Clean
Ch. 2 = Vintage Lo-Gain & Vintage Hi-Gain
Channel Controls Each Channel features Independent Multi-Soak Power Controls (back panel) - Channel 1 (Clean) features Gain, Treble, Mid, Bass and Master - Channel 2 (Footswitchable Vintage Lo-Gain & Vintage Hi-Gain) features Gain, Treble, Mid, Bass, Master-Lo and Master-Hi
Graphic EQ and/or Contour n/a
Reverb / Effects & Bypass Options All-Tube, Long Spring Reverb with Global Control and Auto Reverb Defeat Switch for Vintage Hi or Vintage Hi & Lo Modes (Defeat Mode removes Reverb from the selected mode or modes - "On" Mode applies Reverb to all Modes) - See True-Bypass Options below for more information
Effects Loop & Bypass Options Fully Buffered FX Loop w/Automatic True-Bypass which completely removes itself when nothing is plugged into the FX Send and Return - See True-Bypass Options below for more information
Global Output Level Control n/a
Global Solo Level Control & Bypassable Options n/a
True-Bypass Options Reverb True-Bypass Switch removes entire Reverb Circuit from amp (all modes) - FX Loop w/Automatic True-Bypass which completely removes itself when nothing is plugged into the FX Send and Return
Tuner Output n/a
External Switching Jack Options and/or Midi External Switching Jacks for Vintage Low/Hi (Clean is default)
Speaker Outputs 8 Ohm / 4 Ohm Switch with Two Speaker Jacks
Cabinet Simulation - Direct Live/Recording Output n/a
Headphone Output n/a
Slave Output Yes with Level Control
Weight 53 Lbs.
Dimensions 11" H x 26 3/4" W x 11 3/4" D

Channel 1offers CLEAN, a decidedly American circuit, that chimes with bell-like clarity on the top and is filled out with bouncy, tight low-end that's warm and rich, but doesn't get tubby. CLEAN produces angelic rhythm chording sounds, but because of its tucked bass frequencies, also clips beautifully when used with its dedicated on-board Power Soak for either pushed bluesy rhythm or old-school overdriven solo sounds.


Channel 2 pays tribute to both classic and modified British sounds, and though the two Modes in this Channel share Tone controls, they are adept at delivering amazing, no-compromise footswitchable performance. LO focuses on that touch-sensitive region of gain produced by classic Brit circuits and will have you knee-deep in hit-making sounds instantly.

The undeniable beauty of this gain region lies in the ability to dictate the sound based upon your picking technique, now further enhanced by the addition of Mutli-Soak. Pick softly and LO will purr through stormy seas of Blue or, lay into it and deliver the classic Brit gut-punch…tight and thumping. LO has enough gain to crunch, yet retains the dynamics in the attack and is not too saturated.

HI covers the widest spectrum of gain in the RA100 and though its moniker suggests "over-the-top", some of its best attributes are to be found at settings in the low to middle regions of the evening watch. HI transforms from a sweet harbor for lower-gain, English-Blues bliss at the shallow end of the GAIN control, to an angry, raging tempest with fathoms of harmonics riding just below the surface as you taunt its furthest reaches.


INTRODUCING MULTI-SOAK. At last you can have whatever amount of power amp drive you need to deliver your personal form of magic in every Mode at any volume level you desire. Let's say that again; now your Tone doesn't have to be directly tied to your volume. And one last time; you can dial-in the perfect amount of power-clip for every footswitchable sound in your amp. Okay, yeah the intro might be a little over the top...but damn... How long have we all struggled with that compromise? And though Power Soaks of many persuasions are nothing that doesn't rob your Tone are much harder to find. The ability to have a Power Soak that gives you separate control of the power level and output for each Channel or Mode in your amp and also their different volumes in one built-in package...well you've just sailed off the edge of the map and into a New World of Power Expression.


The Royal's got Reverb. Lush all-tube Reverb drenches the RA100's three Modes with a beautiful 3-D halo and provides assignable choices on where to use it for the best footswitchable results. A 3-position Reverb MODE DEFEAT mini toggle in the REVERB section of the Rear Panel allows you to have the Reverb active in all Modes "ON" (toggle center), Defeated in HI (On in CLEAN and LO) or Defeated in LO and HI (On in CLEAN). The RA100 also provides a master REVERB BYPASS switch that enables you to remove the REVERB circuitry and all associated tubes from the signal path for a more true-to (at least Brit) vintage response. And if you still need more control than this sophisticated approach to applying REVERB offers, we've provided a "hidden Reverb kill" jack on the tube side of the chassis giving those who don't mind the dance, total control.


The handy BIAS SWITCH that allows you to swap the stock compliment of EL34s with the fatter, rounder sounding 6L6s; for those who want to lean heavily on American culture when it comes to crunch time (and even more so in CLEAN).


A transparent Series EFFECTS LOOP handles outboard signal processing aboard the RA100 and provides a seamless interface for units that don't want to be "in front of the preamp" such as Delay, Chorus, Flange and Pitch Shifting based effects. The Loop SEND is derived from a source at the end of the preamp and the RETURN is inserted back into the signal path near the input to the power section. The Loop is basically a patch point at the junction of preamp and power amp and this delivers the best signal to noise ratio and the least degradation of signal for most outboard devices. Well that's about it for a feature overview of the Royal Atlantic, now it's about taking her out for a cruise and seeing what the Royal will do in the wide open ocean of your creativity.