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Mesa Boogie TriAxis Review – King of The Rack Preamps!

    Hello there and welcome back to yet another great article for you! This time we will be looking at possibly one of the best tube guitar preamps ever known to mankind, the Mesa Boogie TriAxis!

    In this Mesa Boogie TriAxis review, I will be providing you with some solid information as well as multiple TriAxis demos that I have prepared for this article.

    As many of you already know, from the 80s to almost 2000s, all-tube, MIDI-controllable guitar preamps were on the rise and very popular among guitar players. However, with the introduction of guitar amp simulation software and processors, they lost a big share of the market and slowly disappeared.

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    There are still guitar players out there who have a huge interest in these legendary tube preamps and are looking for them in the used market. As I am also very interested in preamps and a very big fan of the designs that are so advanced and ahead of their time, I can’t resist but regularly check out the used market for potential tube guitar preamps.

    Recently, I was eyeing Mesa Boogie TriAxis preamps on Reverb but never really wanted to invest as I didn’t have time to play much guitar. But once I felt ready, I immediately jumped on an offer and got myself a TriAxis v2.0 TX4 Recto Board version.

    As most of my regular visitors are already aware, I almost always play through KRK Rokit G5 studio monitors using either guitar amp plugins and software or my beloved ENGL E570 tube preamp with IRs.

    Right after I placed my TriAxis within this setup, I was blown away by the tones it was able to generate. Even though I don’t have a tube power amp and proper guitar speakers, it sounds like any Mesa Boogie you could think of!

    Mesa Boogie TriAxis Front Panel

    8 Boogie circuits in a box!

    Before we go into the review and TriAxis demo video, let’s first have a look at the features of this ingeniously designed tube preamp.

    Mesa Boogie TriAxis Features

    Mesa Boogie TriAxis was first introduced in October 1991. Even though there were a couple of different versions or iterations of it, the main features were pretty much the same. It has 5 12AX7 or ECC83 tubes, and ships with Mesa Boogie branded tubes.

    On the front panel, you have ahead-of-its-time digital controls that will allow you to shape your tone as well as store them in your favourite combinations along with programmable footswitches and FX loops.

    Accessing Programs and Presets on TriAxis

    You can consider “Programs” as MIDI locations and “Presets” as sounds. To access programs, you need to press the “Shift” key one time and then use the arrows below the Gain, Treble, Middle, Bass and Lead Drive windows. Once you’re on the desired program, you can then press “Enter” and access the program listed at the location.

    To access “Presets” within the programs, you need to press the “Shift” twice and activate the “Preset” window. And then select your desired preset using the arrows below the “Preset” section.

    There are a lot of features here such as mapping a preset to a program, copying presets to another preset location, setting MIDI channels, dumping and receiving the MIDI and also recalling factory presets and many more.

    To understand these in greater detail, I suggest you check out the official manual. Unfortunately, there’s only a single version of the manual and the modes may differ as there were different iterations of this unit. However, you can easily learn all the functionalities by reading this manual carefully.

    Check out Mesa Boogie TriAxis manual here


    On the back of the TriAxis, you also have standard MIDI IN/OUT and THRU for your MIDI operations. There’s also a coax power jack for phantom power with which you can power up your MIDI controller (7-pin).

    Switch Jacks

    Mesa Boogie TriAxis Back Panel

    A wide array of inputs and outputs on the back

    There are 4 separate “Switch” jacks that you can use for controlling or activating external devices (specifically made for Boogie’s products). These are “Tip to Ground” function switches and if you want to use them with any external device other than Boogie’s, you need to contact the manufacturers.

    Output Jacks

    There are also a pair of “Record” and “Output” jacks on the back of your TriAxis. Record outputs try to imitate an analogue speaker simulation which you can directly record into your DAW. But note that, these were designed in the early ’90s, so do not expect IR-quality direct recording.

    Also, using a pair of standard outputs, you can connect your TriAxis to a power amp or an audio interface and then use IRs to directly record.

    The Controls on the Front Panel

    Boogie TriAxis features pretty standard-looking controls on the front panel. But with some slight Boogie twist as usual! You have your “Gain“, “Treble“, “Middle“, “Bass“, “Lead Drive 1” and “Lead Drive 2” as well as “Master“, “Presence” and “Dynamic Voice“.

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    To understand what Boogie suggests for setting up the gain stage and how these controls react with each other, you should check out the official manual.

    Check out Mesa Boogie TriAxis manual here

    As you can see, you have 2 Lead Drives and these correspond to the different modes that the unit offers. So when you are on one of the e.g. Lead 1 modes, only Lead Drive 1 can be used. In this case, adjusting Lead Drive 2 won’t do anything to your sound.

    Apart from standard controls, you may already notice there’s also a control named Dynamic Voice. Dynamic Voice is a unique feature of the TriAxis. It’s designed to include Boogie’s famous 5-band EQ with slight differences. It does not only act as a graphic EQ but also as a blend of dry and EQ’ed signals at the same time.

    The higher you set it, the higher the dry/wet signal gets as well. When it’s set at 10, the whole signal is passed through the Dynamic Voice.

    To understand how these Dynamic Voice values refer to specific 5-band graphic EQ curves, please have a look at the image below (taken from the manual).

    Mesa Boogie TriAxis Dynamic Voice

    The TriAxis Modes

    TriAxis features 8 preamp circuits from Boogie and can be easily considered the encyclopedia of Boogie tone! These preamp circuits are placed under 3 main categories Rhythm, Lead 1 and Lead 2.

    Before we dive into details, I would also like to share the modes overview taken from the official manual. Note that, this belongs to the current, latest manual you can find on Mesa Boogie’s website and doesn’t mention the “Recto Vintage” circuit. For the different versions of TriAxis, please read on and check out the versions section.

    Mesa Boogie TriAxis Modes Overview

    Rhythm Modes

    Under Rhythm Modes, you have Green and Yellow modes.

    Rhythm Green is more like a vintage, Fender Black Face-style circuit. It’s designed with a lower bass response but with quite a lot of sub-harmonic bass frequencies. The top end is also lower than the Rhythm Yellow but may be perceived as higher or lower depending on how you set the midrange control.

    When the midrange is set to lower settings, the upper harmonics become more pronounced. With these settings, setting also the gain control lower, you will have bubbly, elastic high frequencies and big, open low frequencies.

    Setting the gain and midrange around 5.5 to 7.5 also generates great usable tones defined as bold and pushed yet still clean. On top of that, maximizing the gain control and midrange generates excellent solo sounds as well. According to the manual, this mode was inspired by Fender Bassman 4×10 amps then later redefined as Mesa Boogie Mark 1.

    Rhythm Yellow on the other hand features a much different response than the Rhythm Green mode. Mostly on the bottom end in terms of amount and frequency density. Rhythm Green mode is defined as a tighter and quicker attack. Also, the top end is more percussive yielding a more open, clean sound.

    This mode can be traced back to Boogie Mark IV, III and IIC+ according to the manual. Both these Rhythm modes feature a dynamic bright circuit that causes the gain control to act as an additional tone control. The lower the gain, the more top-end harmonics are allowed to pass through. When the gain is set around 3.5 to 5.0, it generates great tones with a lot of sparkles for almost mix-ready funky guitar tones.

    When the gain is increased to around 6.5, it becomes more aggressive and around 8.5, it starts delivering semi-clean tones that will sit very nicely in the mix as well. Above 8.5, it acts as a lead mode. So even though, it says Rhythm mode, you can already have so many different guitar tones that you can shape with the controls and TriAxis’ interactive circuits!

    The manual includes a lot more tips and tricks on each mode, so I highly suggest you check it out yourself and read it carefully. As Boogie had put so much time into making these circuits perfectly musical, as they suggest one should be just relaxed and take their time to discover the endless possibilities that TriAxis offers!

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    Lead Modes

    Lead modes consist of 6 different modes under Lead 1 and Lead 2 modes. Let’s have a look at them below.

    Lead 1 Modes

    Lead 1 modes are based on more traditional and older Boogie circuits, meaning that they all feature pre-tone-control gain circuits. So boosting the gain control within this mode pushes the preamp tube before the tone controls. With this approach, these circuits can generate guitar tones that are larger but less focused. These can be also described as loose and more spread-out tones.

    As opposed to the rear-end approach in the circuits, this design allows it to pump a lot more bass without being flabby or cloudy. Therefore, it’s ideal for hard rock and metal players who like to maximise their gains. Mesa Boogie specifically recommends Lead 1 Red mode for these kinds of applications. Boogie also suggests that one should first try to explore these modes without Dynamic Voice engaged.

    The Dynamic Voice should be still usable with Lead 1 modes but ideally designed for Lead 2 modes as they feature the circuits that are famous for their success in combination with the graphic EQ (post gain).

    Lead 1 Green

    Lead 1 Green features the Boogie Mark I circuit that was also used by Carlos Santana in his Abraxas album. According to Boogie, Lead 1 Green mode is a true replication of the Mark I (Input 1). It’s defined as fat, warm and round with sweet, sparkling highs just like the Black Face era of guitar tones.

    As Boogie can generate the exact circuit, they also featured the unique approach in Mark I featuring the volumes or gains working in series. As a general rule of thumb, the gain set higher than the Lead 1 drive on TriAxis generates more blended saturated sound. The opposite setting generates a brighter and slightly hollow character.

    In this mode, treble and middle controls are also designed as active gain controls. So it’s suggested to experiment by adjusting these controls along with gain and Lead 1 drive.

    Lead 1 Yellow

    Lead 1 Yellow is pretty much the identical circuit with Lead 1 Green but there are several switches activated when this mode is selected. Firstly, this mode features more gain, tighter and more focused sounds.

    On top of that, it also has a mid-boost implemented within mid-treble regions, resulting in less bright, more bold and beefy tones. These features in combination with each other provide a liquid feeling. Boogie suggests trying out treble and presence around 5.0 or below. The voice of this mode is darker, warmer and smoother than the Lead 1 Green mode.

    Lead 1 Red

    Lead 1 Red mode also features a lot of the attributes coming from Lead 1 Green and Yellow modes. But it also features an added focus and punch in the upper mid-range. Because of this punch, it easily cuts through the mix and is very useful for classic and modern gain settings.

    The tuning of this mode has a tighter bass response and allows more treble to be added which results in increasing the gain without sounding thin. Boogie suggests setting the gain at 8.0, bass at 6.5, treble at 7.0 and lead 1 drive at 6.0.

    Even though, the “current” official manual says this is the classic British Lead mode, the TriAxis v2.0 featuring TX4 Recto Boards has this mode as the Recto Mode.

    Mesa Boogie TriAxis TX4 Recto Board

    Infamous TX4 board!

    Lead 2 Modes

    As mentioned above, Lead 1 modes were pre-tone-control gain controls. However, with Lead 2 modes, it is quite the opposite. Lead 2 modes feature a post-tone-control gain circuit. This design approach was done for the first by Mesa Boogie company in their Mark II series. Following this groundbreaking approach in amp design, Mesa Boogie also featured this in Mark II-B, II-C+, III and IV series amplifiers.

    Generally speaking, Lead 2 modes offer more articulate and focused lead sounds and can be easily described as not so forgiving. All these modes cut through the mix, stay focused much longer and allow players to be heard.

    Lead 2 Green

    As you remember, in Lead 1 modes amount of gain that you can get differs in each sub-mode. However, in Lead 2 modes, the gain structure and the amount are pretty much similar to each other.

    Boogie decided to add legendary Mark II, II C+ and IV circuits to feature in this mode. According to the manual, the Lead 1 Green is taken from Mark IV‘s lead channel and features the mid gain added to the Mark IV in the late ’80s. It’s focused and thick-sounding mode while keeping everything punchy.

    As you can see from the section on Lead 1 modes, even though Boogie suggests a lot of settings and starting points in setting up the recommended presets, in Lead 2 modes they came up with a single rule of thumb.

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    Try setting the gain at 7.0 or 7.5 for blues sounds or articulate mid-gain tones. If you need more than that, try increasing the gain up to 8.0 and see if these work as intended!

    Lead 2 Yellow

    This is probably one of the best and sought-after modes in the TriAxis. It features the circuit that started everything back in the day, helping guitarists and bands to form one of the greatest guitar sounds that we would listen to on the legendary albums by Lukather, Keaggy, Lynch, Gillis, Prince and Metallica.

    Lead 2 Yellow mode is the reincarnation of Mark IIC+ Lead mode, featuring bold, punchy and liquid harmonics! This mode is not only suitable for higher gain settings but also great for lower gain settings as well. Dynamic Voice plays a crucial role in sculpting these tones generated by the legendary post-tone-control gain circuits. 

    Lead 2 Red

    Lead 2 Red mode is often called the Shred mode by Boogie fans. This mode features a lot more aggressive top end than the yellow mode and boosted upper harmonics. According to the manual, it is a Mark III circuit named Searing Lead. This is often confused with the “Recto” mode which is the Lead 1 Red mode on the TriAxis v2.0s featuring the infamous TX4 Recto Board.

    However, in the manual Lead 1 Red mode named Classic British Lead. I’m not sure if this official manual was written for the latest TriAxis builds featuring “Phat Mode”.

    Based on my pretty short-term experience with the Mesa Boogie TriAxis, I must say I’m very impressed by all the sounds in this magnificent preamp! Please continue reading the article and check out my demo videos featuring factory presets of the TriAxis!

    TriAxis Versions

    As you may have already noticed, we keep talking about versions, different modes, and boards, I assume you are guessing there is more than one version of the TriAxis. Mesa Boogie has a dedicated section on their website which you can access here. I’m also adding a quick summary here below.

    Version 1

    Serial #1 to #1630 – 10/1991 – Software versions 1.4.92, 1.6.3, and 1.6.5 which are classified under Version 1. In this version, continuous control was not a feature. No Phat Mod, no TX4 Recto board.

    Version 2

    Serial #T1631 to T5199 – 1/25/1993 – Software version 2.0. With this software, continuous control was implemented in the unit and parameters can be controlled via MIDI. TX4 Recto board installed which caused a change in Lead 1 Red mode from “British Lead” to “Recto Vintage” circuit. To quickly check if you have version 2.0, just have a look at the parameters blinking 2.0 when the device is turned on.

    Serial #T5200 to T8278 – 3/1997Phat Mod. This Phat Mod impacts the upper mids in the Lead 1 Red mode. To quickly check if the unit has Phat Mod or this mode removed, just have a look at the TX4 board by removing the lid and checking the missing parts on the top left.

    Serial #T8279 until discontinued – 10/2004 – TX4 board removed due to unavailability of parts. Lead 1 Red reverts back to “British Lead”. No Phat Mod.

    Mesa Boogie TriAxis Review

    As I mentioned in the beginning, I can’t help but want to try these legendary tube preamps as long as my budget allows me to do so! 🙂 TriAxis was one of the earliest preamps I had ever seen used by my guitar teacher back in 2000. Since then, I have been aiming to own this preamp and try. However, due to not being easy to grab in the used market, I always postponed and ended up with another legendary tube preamp, ENGL E570!

    Check out my ENGL E570 review here

    I still love my ENGL E570 tube preamp, but as it sounds like ENGL, I find it rather too unique! What I mean by that is if you grew up listening to musicians and bands playing Marshalls, Fenders and Boogies, ENGL wouldn’t sound familiar to them. But it’s also an edge as you can create your own, unique sounds as opposed to just attempting to replicate others.

    But when I got my TriAxis, I felt like most of the sounds it can generate were very familiar to me. So I don’t regret this decision and I would like to spend some time with my TriAxis and hopefully will release a lot of comparisons between TriAxis, ENGL preamps and my Marshall JVM410 head.

    In short, I recommend any guitar player to try a TriAxis before they leave this world! Seriously, you need to experience this wonderful, ahead of its time design!

    It offers so much variety and just feels like an encyclopedia of Boogie tones! Using it is so easy and with its digital parameters, it is a breeze to program and even copy the presets of your guitar hero who also uses TriAxis!

    I bought mine used and unfortunately, the right rack ear was kinda bent while transport, however, the unit is in very good condition considering its age! Also, you can see from the image of the circuits, it looks very clean. I think it’s expected that your used TriAxis may have lots of cosmetic issues as well as functional issues as these are ancient devices. But if you are lucky, you can get your hands on one in great condition.

    As I mentioned, it immediately sounds like home! If you ever listen to bands and musicians that used Mesa Boogie TriAxis or any Mesa Boogie amps, chances are that you will feel the same! All the sounds will sound familiar to you immediately which is a great thing.

    Mesa Boogie TriAxis Sound Demo

    Now the fun part begins! To show you what a Mesa Boogie TriAxis sounds like, I prepared some demo videos for you! Note that, I’m not done yet with recording all my guitars, however, you can already watch and listen to my TriAxis demos featuring my Fender American Standard Stratocaster (Custom Shop Fat50 Pickups) and Epiphone Les Paul Custom Ebony (ProBucker2 and ProBucker3 Pickups). The signal chain for every TriAxis video will be the same with different guitars.

    In the series of videos, I aim to provide you with useful videos to demonstrate Mesa Boogie TriAxis presets!

    Signal chain: GuitarMesa Boogie TriAxis > Marshall JVM410H (Power Amp Send) > Red Seven Amp Central (using Celestion V30 IRs featuring SM57/414 mic combo) > RME Babyface Pro > Reaper (Eventide SP2016 room reverb)

    Boogie TriAxis Demo featuring Fender Stratocaster

    Boogie TriAxis Demo featuring Epiphone Les Paul Custom

    I hope you enjoyed the sounds of TriAxis with different guitars! I believe it’s not easy to find TriAxis sound samples with different guitars featuring all the circuits. Usually, people tend to play only heavy stuff with TriAxis, but I think it has a lot more to offer. You have the entire Boogie history in a compact, programmable box which is way ahead of its time! Cleans and overdriven sounds are so sweet and feel awesome in your hands!

    If you want to hear more of TriAxis v2.0 TX4, please stick around. Because I will be preparing a lot more demo videos for you to check out!

    Where to Buy TriAxis?

    If you are ever looking for TriAxis for sale on the internet, chances are you may find some on and eBay as well. There are even almost brand new conditions pop out from the forgotten storage of an abolished guitar store here and there.

    Check out for Mesa Boogie TriAxis for sale!

    Even though version 2.0 TX4 board is considered the holy grail of TriAxis, I believe other versions also sound great. But if you want that vintage Recto sound which is great in my opinion, you may need to stick to the common approach by Boogie lovers!

    As I mentioned in the article, there are some guitar gear that you must try before you leave this world! We are living in a very lucky era as electric guitar players and can try many guitar gears which belong to previous eras and not all of them are necessarily priced like crazy!

    TriAxis is one of them, they still retain their value but you will not see anyone charging 5K for a used TriAxis. Ready to pay about 1400/1500 Euros in Europe for this version and a lot less in the USA.

    Is Mesa Boogie TriAxis worth trying? Absolutely! You will be blown away by every sound and how these feel at your fingertips!

    I hope you find this Mesa Boogie TriAxis review article honest and insightful! Thanks for visiting my blog and supporting me so far! I will hopefully see you in the next review here!

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