A detailed review of the "Brian May" sound from the beginning to now
- written exclusively for www.brianmayworld.com -
The Brian May Sound – A critique on the influence, and importance of the Vox AC30, Treble Booster, and Red-Special Guitar for finding ‘the tone’
by Mark Barnett, aka Yogi, (UK)
The guitar-tone of Brian May, is one of the most distinctive sounds in rock-music. It is a unique tone, distorted yet somehow clean, heavily overdriven but also warm and sweet sounding, and harmonically rich. It has been heard on every one of Brian’s recordings, from his Queen period (1973 to 1995), right through to current day and his solo recordings (1992, 1998).
Throughout this period, Brian’s sound was rated as one of the best guitar tones ever heard, and fans of his were always trying to discover the secrets of the wondrous noise. This unique tone, originated from three principal components. Individually, two of these components were not particularly special or unique, and were widely used by other artists. However, the magic in Brian’s tone occurred when the three components were combined.
These three components were his home made ‘Red-Special’ Guitar (built in1963, by Brian and his father Harold, based loosely around a cross between a Fender Stratocaster and a Gibson Les Paul, both instruments featuring heavily in the music of the day), the British Vox AC30 amplifier (used most famously, for its clean tones by Liverpool’s finest, The Beatles and The Shadows Hank Marvin) and a simple single-transistor electronic device called a Treble-Booster (used by many artists in the 1960s to further improve the overdrive characteristics of the then non-master volume valve amplifiers, including Eric Clapton, Toni Iommi, Rory Gallagher, Ritchie Blackmore…..).
In this article, we will individually examine and assess the tonal contribution of each of these items, what in particular makes each different from other similar equipment, with the aim of further understanding the magic of the ‘Brian May Sound’.
‘The Brian May Rig’
The Red-Special Guitar (here a modified 1993 Guild).
The Treble-booster (here the small red box on the floor, a Grey Fryer model)
and finally the Vox AC30, here a modified Vox, with the Brilliant and Vibrato channels circuitry removed, and the Normal Channel Circuity uprated to stand the rigours of ‘Brian-May mode’ (see text on the AC30 for more details)
Thanks to Martin Pitcher for the use of this picture, the owner of the equipment shown here.
The ‘Red-Special Guitar’
(Greg Fryers opinion on contribution to the May sound – 40%)
The Original 1963 Red-Special Guitar
The story about the creation of the Red-Special Guitar in 1963 by Brian May and his father is now well known.
(see http://www.brianmayworld.com/redspecial_details.htm for example), but it is worth partly reciting in order to familiarise ourselves with the stranger aspects of the instrument, and how they help influence its tone.
Firstly, let consider the body woods – although mahogany is widely used in guitar making (perhaps the most famous example of the use of mahogany being in the Gibson Les Paul), neither Oak nor Blockboard as far as this author is aware have ever been used in commonly available instruments. These woods help to impart a distinct tone on the instrument, in particular the oak onto which the bridge and pickups are mounted and which is also the fingerboard material.
Next, the semi-hollow nature of the body-itself should be considered, containing several ‘acoustic pockets’ designed to increase the natural resonance and sustain of the instrument.
Finally, Brian’s use of pickups is also unusual as is his method of wiring them. The pickup of choice were the quite rare 1960s design Burns Trisonics. Although these pickups are constructed from only one single coil, they have the physical size and almost the power of humbuckers. These were then wired not in parallel, as is the wiring method on the Fender Stratocaster and Gibson Les Paul, but in series. This, along with his six individual switches for adding (or subtracting, with the phase switches) individual pickups to the output signal, allows the construction of humbucker type pickups (which are two single coil pickups, wired in series), giving a greater, fuller signal with more presence than would have been possible using parallel wiring.
The Vox AC30
(Greg Fryers opinion on contribution to the May sound – 30%)
The Vox AC30 in its classic Black Covering.
Reproduced from www.voxamps.com
The Vox AC30 is a 33 Watt, 2x12 Celestion speaker loaded, EL84 powered ‘Class-A’ valve amplifier. It was introduced in 1959, as a 4-input amplifier (AC30/4) meant to provide the tone of the less powerful 15 Watt AC15 but with more volume and clarity. In 1961, the amplifier design was changed slightly by adding a further channel, the ‘Top Boost’ or ‘Brilliant’ Channel which added a little more gain (AC30/6 or AC30 TopBoost).
It is currently available in two formats, both AC30/6 types, one utilising the Celestion ‘Greenback’ speakers, the other slightly more expensive version due to the use of cobalt material utilising the Celestion ‘Blue’ speakers. Of the two types, Brian prefers the latter, but has recorded with the former too, with the guitar tone on Queen’s ‘Flash Gordon’ being perhaps the clearest example of the Greenback tone.
Although the amplifier possesses three, non-footswitchable channels, the ‘Vibrato’, the ‘Normal’ and the ‘Brilliant’ channels, only the ‘Normal’ channel is utilised by Brian.
As the vibrato effect on the ‘Vibrato’ channel cannot be turned off, this channel is of very little use for rock guitar playing.
Next, the tone of the ‘Brilliant’ channel, although featuring the highest gain of the three-channels has, in addition to the increased gain, a large increase in treble at the expense of the bass and middle ranges of the tone. Two tone controls, labelled ‘Bass’ and ‘Treble’ which act only on this channel, cannot quite balance this tendency for a treble-rich too bright (hence the channel name, brilliant) tone.
Conversely, the ‘Normal’ channel has no tone controls at all, except a low-pass filter control labelled ‘Cut’ which acts to filter out the treble end of the tone and which can be completely bypassed and is relatively low gain in comparison to modern amplifier designs. However, the tone of this channel, which due to the lack of tone-controls is ‘hardwired’ in to the amplifier design is extremely well rounded, offering just the right balance of bass, middle and treble.
As the amplifier does not possess either a gain-control to regulate the amount of gain in the pre-amplifier of the selected channel, or a master volume to regulate the overall gain of the power-amplifier and hence overall volume of the amplifier, it is more difficult to handle than modern amplifiers. In order to induce a distorted or ‘overdriven’ sound into the amplifier, it must literally be overdriven. In order to do this, the amplifier volume control for the required channel must be opened to allow the power-amplifier valves to produce greater power. This type of overdrive is then mostly the much more desirable power-amplifier distortion, as the AC30 pre-amplifier especially when using the ‘Normal’ channel remains extremely clean even at full volume. The particular characteristics of the very clean pre-amplifier signal gives the AC30 one of the very best ‘clean’ sounds of any amplifier, as evidenced by its use by Hank Marvin.
This is partly explained by it being a Class A amplifier, without any of the harsh distortion induced by the power-valve cross-over present in the majority of valve amplifiers (Marshall, Hiwatt, MesaBoogie). These manufactures use Class AB1 designs and must try to reduce the cross-over distortion intrinsic to Class AB1 to minimal levels.
The unique AC30 tone is also partly explained by it possessing zero negative feedback, also a rare design feature, and finally by the presence of a GZ34 valve rectifier in place of the more common solid-state rectifiers. Although several commercially produced amplifiers are available incorporating up to two of these three characteristics, only the Vox AC30 possesses all three. This is an important consideration in defining why the AC30 sounds unique in both clean and overdriven applications.
(For a more thorough explanation of these technical aspects of Valve amplifiers see http://www.duncanamps.com/technical/ampclasses.html, http://www.audiovideo101.com/dictionary/class-a.asp, and
When finally any of the three channels volume controls of the AC30 are wound fully open it produces what has been described as a ‘Vintage’ overdrive tone. It is a rich, full complex sound. However, it does not possess particularly large amounts of gain, and the amplifier in this state has neither a ‘Brian-May tone’ or a particularly satisfying tonal balance, the bass response of the tone having increased with the increasing volume.
It does however, even though overdriven, still produce cleaner sounds, simply by the reducing of the input level, or the guitar volume control. It is this aspect in particular that Brian May has found to be particularly pleasing:
“What I wanted was a guitar amplifier which would sound clean and bright at low levels of amplifications, but smoothly slide into the kind of distortion which on a single note didn't sound like distortion but more like a violin”
“The quality at low levels is broad and crisp and unmistakably "valve like", and as the volume is turned up it slides very controllably into a pleasant creamy compression and distortion.”
(The Vox Story, Introduction by Brian May, page 9)
If the bass-response of the fully-open ‘Normal’ channel were to be reduced, and a little more overdrive induced, then all of the benefits described above could be gained – as this point, we will describe the Treble-booster device.
(Greg Fryers opinion on contribution to the May sound – 30%)
The Greg Fryer Treble Booster.
Brian’s current favourite, shown here sitting on the top of an AC30, next to the cooling vents.
Thanks to Martin Pitcher for the use of this picture
The Treble-Booster is a very simple battery powered device employing up to three transistors to boost the guitar signal, and a simple network of resistors and capacitors to shape the sound and give it the right frequency balance. All of the three-boosters below act to perform this same task. By boosting the guitar signal by up to 32dB (from typically around 500mV, the signal from a ‘hot’ humbucker to several volts), the relatively low gain of the Vox AC30 becomes unimportant as the signal has already been significantly amplified.
It is important to realise the difference between a Treble-Booster and an Overdrive or Distortion pedal. The Treble-Booster takes a small totally clean and fully sinusoidal input signal from the guitar, and simply increases its amplitude – all of the tonal nuances coming from the guitar pickup are preserved, as is the full sinusoidal nature of the waveform. This huge increase in amplitude further overdrives the valves, creating more of the highly desirable valve distortion. This is very different from the latter Overdrive or Distortion pedals, which simply convert the sinusoidal guitar signal into a square-wave signal, with approximately the same amplitude. As the signal level itself has not increased (only its shape having changed) there is no increase in the amount of the much preferred valve-overdrive tone the amplifier generates. Thus a Treble-Booster causes the amplifier to give more of its natural valve distortion.
Also, the levels of boost present from Treble-Boosters, generally 25-32dB, are far greater than the increase in levels associated with the tone-controls on most amplifiers. These typically only change the tone response by around 3-8dB. Hence, simply increasing the treble-response using the amplifier controls will not replicate the action of adding a treble-booster to an amplifier.
Finally, the term ‘Treble’ is added to the title, as although all the frequencies and harmonics present in the guitar signal are greatly boosted, the treble end of frequencies is boosted a little more, to reduce the otherwise heavy Bass response of the AC30.
Thus the pre-amplifier section of the AC30 achieves full saturation, where normally it does not, and this much larger signal is then fed into the power-amplifier causing further distortion and an increase in the favoured power-amplifier overdrive component in the final tone. This then allows Brian to drive the AC30s into giving overdrive tones comparable to that that achieved by much higher gain amplifiers.
Below are described the main characteristics and tones associated with the three types of treble-booster Brian May has commonly employed.
The Rangemaster (used by Brian May on Queen Recordings Queen I, Queen II, A Night at the Opera
The Rangemaster is perhaps the most famous Treble-Booster produced. Employing a Germanium transistor, it has a distinctive raw metallic sound, similar to that produced by a half-cocked Wah pedal. Although not as full sounding as the Cornish or Fryer boosters, or able to produce quite the same boost levels (estimate around 25dB),
The use of Germanium has produced a highly distinctive tone – examples include the opening of Sweet Lady, Great King Rat and Brighton Rock.
Brian’s original Rangemaster pedal was lost around early 1976, and Brian then approached Pete Cornish to construct him a new Treble-Booster.
The Pete Cornish TB83 Treble-Booster (used by Brian May on all Queen recordings not included above, Starfleet Project, Back to the Light.) Available from http://www.guitarexperience.com, 180 pounds.
The Pete Cornish TB83 featured on virtually all of the Queen albums, and hence is the Treble-Booster of choice for producing the Queen tone. It uses Silicon transistors, and offers a much greater boost then a Rangemaster, at 32dB the greatest of the three here. It also offers less treble-boost and more general boost, providing a fatter tone.
There are many examples of this tone – including The Hero (Flash Gordon), One Vision, Hammer to Fall, Tie Your Mother Down, as just tracks with a prominent guitar part, and many many more.
The Greg Fryer Treble-Booster (used by Brian May on Another World and all subsequent performances). Available from Greg Fryer. See http://www.brianmayworld.com/GregFryer_products.htm
This booster is now Brian’s favorite. A similar Silicon design to the Cornish, but offering slightly less boost (around 30dB), less noise, and a little more treble-response and bite. This is the pedal for anybody wishing to produce Brian’s current favourite tone.
Examples of the Fryer Booster include – SideBurns (specially commissioned track to showcase the tone of the Burns Red-Special guitar, hence a boosted guitar level on this track), Cyborg and Business (the latter tracks featuring on Brian May’s 1998 solo album Another World).
Perhaps the best description of just what happens when you put these items together is given here – http://www.brianmayworld.com/VOX%20AC30TBX.htm. As an owner of a Red-Special, several Treble-boosters and a Vox AC30TBX, I will further endorse the opinions in that article, in that such a simple setup does indeed produce the Brian tone, and in volumes that need to be heard to be appreciated. As the Vox AC30 requires the ‘Normal’ channel volume to be on full volume to give the required overdrive characteristics, the amplifier is obscenely loud. Hence, anybody wishing to reproduce the Brian-tone at lower volumes should responsibly consider the purchase of a “power-break”, of which the most common types are produced by Marshall Amplification: (http://www.marshallamps.com/images/products/powerbrake/powerbrake.html) and THD Electronics (16 Ohm version required, http://www.thdelectronics.com/products/hotplate.htm)
Although the Vox AC30 has been in almost continuous production since 1959, both Treble-Boosters and Red-Special type guitars have been far more scarce and difficult to obtain, making the task of producing the Brian-May sound more difficult.
Over the past few years though, Red-Special guitars have again become commercially available. Also, with the price ranging from just 500 pounds to 3000 pounds, of most significance is that there is now a Red-Special within the financial reach of virtually everybody (see “Something for the Rich, Something for the Poor, Something for those who Want Even More” on www.BrianMayWorld.com for a review of the currently available instruments).
Also, following Greg Fryer’s restoration of the Red-Special in 1998, the subsequent rise in interest of Brian’s work, has enabled Greg Fryer to market several Brian May effects pedals, three of which are Treble-Boosters.
So, there has never been a better time to be a fan of either Queen, Brian May, or the “Brian-Tone” than now – let’s all get out there and astound everybody by our guitar tone, courtesy of Brian May.
The author wishes to thank Oliver Tamminga and Mark Reynolds for help in the preparation of this article.