Marshall Amplification BOOK-00079-00 manual Kvtyztr @W`cReZ`, James TappyWright

KVTY_ZTR] @_W`c^ReZ`_

Components: Wherever and whenever possible, we have gone back to the original manufacturers for all components to ensure maximum authenticity.

Valve compliment: Three ECC83s in the pre-amp and a quartet of KT66* valves in the power amp working in push-pull. All valves are of the highest quality available and are subjected to our stringent grading and testing processes.

*KT66: these output valves were standard issue in mid-sixties Marshall Amplifiers and yield a fat, round tone that has a distinctly vintage flavour.

The way the pre-amp’s three ECC83s (labelled V1, V2 & V3 in the photograph) are utilised is as follows -

V1 is the first pre-amp gain stage for the High Treble and Normal channels. Each half of the valve (the ECC83 is a dual-triode which means it is literally two triode valves in one) acts as a dedicated gain/input buffer stage for each channel.

V2 is common to both channels which are summed at the input of this valve. The first half of V2 acts as a second gain stage which boosts the signal further and directly drives the second half of the valve which is configured as a cathode follower (providing a high input impedance and a low output impedance for the signal to drive the pre-amp’s passive tone network).

V3 is the amplifier’s phase inverter and sits at the very end of the pre- amp section. V3 divides the single ended input signal into two separate output signals that are inverted with respect to each other - hence the name ‘phase inverter’ (a.k.a. ‘phase splitter’). The two resulting signals are then fed to the push-pull power output stage of the amplifier.

Output Transformers: The Output Transformer in your Super 100JH is identical in every single aspect to the original ones used back in 1966. The inclusion of the fully functional 100V Line tap, while being historically correct, is of little or no use on this particular model, if truth be told! The reason it was present in the 60s was because the same transformer was also used in the

100-watt Super PA heads (model 1968) as well - enabling the head to drive multiple remote 100V line speakers in various locations within a particular venue.

Power supply: This circuit has the same filtering on the H.T. (high voltage DC, a.k.a. the B+ voltage) line as the original versions, a factor that contributes to the Super 100JH having a unique, dynamic characteristic all of its own. The power supply on the Hendrix head is notably different to that of the post '68 Plexis and, when the amp is fully cranked, has a very different regulation (i.e. its ability to supply what is demanded from it). This coupled with the period correct smoothing capacitor values produces that characteristic ‘sag’ (compression).

Chassis: We are using a box-section chassis made from 16- gauge mild steel with butt-welded corner joints. The steel is also passivated, giving it lifelong resistance to corrosion. This is a deviation from an original 1966 Super 100 head as it had an aluminium chassis. The reason we have made this change is for strength, longevity and reliability reasons, and we can assure you that it has no tonal effect whatsoever. Aluminium is a very soft metal and the one thing that all chassis from this period have in common, is they are easily distorted, buckled, bent or even cracked - due to the material's inherent weakness. A lot of this can obviously be attributed to the sheer size and weight of the

transformers. The steel chassis used in your Super 100JH doesn’t suffer from such problems and is much more practical and roadworthy.

Front Panel: Extra thick, gold coloured Plexiglas (actually Perspex, causing some people to refer to it as ‘Perplexi’!), exactly the same as the original. And, just like the original, the front panel is that of a JTM45 (hence its ‘JTM45’ nomenclature) - used on the first Super 100s as standard. Specific details pertaining to the front panel features can be found on the next page of this manual.

Rear Panel: Made from cream styrene with gold print, just like the original reference units. Specific details pertaining to the rear panel features can be found on the next page of this manual.

Head Cabinet Construction: High-grade, flawless (knot-free) Baltic birch-ply with finger-locked (a.k.a. ‘comb’) joints for maximum strength. The main cabinet frame (sides, top and bottom) is 15mm ply; the front baffle is constructed from 12mm ply, while the back of the cabinet is 9mm ply. All edges have a 15mm radius.

Head Cabinet Cosmetics: The small gold Marshall script logo, black Levant covering, original venting, beading and piping all duplicate the look and style of the originals.

“Marshalls were the only amps that could follow Jimi into the musical realms he chose to play in and come out the other side delivering the goods, 100%

James 'Tappy'”Wright

ENGLISH

Tone Circuit: In typical Marshall fashion, the Super 100JH’s shared tone network is both passive and interactive. By interactive we simply mean that the settings of the Bass and Treble controls affect the amount of mid-cut available via the Middle control.

Tag Boards: The tag boards used in your handwired Super 100JH are exactly the same as those in the original in terms of thickness and matrix pitch. The material we’re using is made exclusively for us and is registered with UL as ‘Marshall EM42 brown.’ The reason we didn’t use a board with the exact same chemical composition as in the original units is simple - that material doesn’t pass current safety legislations concerning flammability!

Transformers: The mains (power) and output transformers are vital to the performance, sound and feel of an all-valve Marshall amplifier. In order to achieve authentic tone and performance, we went to Drake for these important components as they are the company that supplied us with the transformers used in the original Super 100. Fortunately, Drake still had all of their original documentation intact in their files.

Mains (Power) Transformer: The Mains Transformer in this re-issue is an exact duplicate of the original in terms of electrical performance and behaviour. This said, some constructional alterations had to be made in order to pass current Safety Legislations. These alterations have no impact on tone or performance whatsoever!

Photo credit - Ulrich Hand / © Authentic Hendrix, LLC - Big Apple Club, Munich, West Germany - 9th November 1966

KT66 POWER VALVES

ECC83 VALVES

V1 V2 V3

“Anybody wanting quotes from Jimi regarding his Marshall Amps will find hundreds recorded on his albums and videos.

Neville”Chester

ENGLISH

2 3