List of updates / new info. on Vox solid state amps (1967-1972)
March and April 2020
A great early grey Wah - no. 5063 (the sequence beginning at 5000) - bought new in Cardiff in 1967 and still owned by the original purchaser. Thanks to Phil for the pictures.
Below, the two principal styles of information plate on Vox Multi-Link speaker cabinets. The first (VSEL) is far clearer than the second (VSL). That said, it is far from perfect. The two cabs bearing the plates both have impedance matching units that allow two further cabs to be attached. It is important to bear in mind the fact that the Multi-link cabs are themselves 15ohm units:
The matcher is straightforward. The INPUT connects the output of a Vox solid state amp (all of which require a 15ohm load) via the matching transformer to the speakers in the ML cabinet. The four speakers in the ML are wired up so as to give a 15ohm impedance. The two OUTPUT sockets are for further speaker cabinets.
The "Vox Sound Equipment Limited" information plate (above) is relatively straightforward. Set the selector to 15ohms when using the ML on its own. Use the 8ohm setting if a further 15ohm cab is plugged in; set to 4ohms when two 15ohm cabs are attached. No advice is given however on how to connect up four 15ohm cabs (ie. the ML and three additional units). A four cab link up is only really possible with a Vox matching unit that had four outputs (some did, but not the one accompanying this plate).
The setting for a single 8ohm cab only makes sense if the ML itself has an 8ohm impedance (not possible with the speakers fitted by Vox). The 4ohm setting is fine for two speaker cabinets of 8ohms, but the means of achieving that is not specified.
The 4ohm setting envisages a single 4ohm cab - which only makes sense, as above, if the ML cabinet is rewired internally for that impedance (which is possible using the speakers fitted by Vox).
The VSL plate gives the impedance required by the amplifier in the first column, and the setting of the matcher in the second.
The first row gives the setting for the ML cab itself, no other attached: - 15ohms
The second row gives the setting for the ML cab + one further 15ohm cab: - 8ohms
The third row gives the setting for the ML cab + two further 15ohm cabs: - 8ohms, which differs from the recommendation on the VSEL plate.
The last row gives the setting for the ML cab + three further 15ohm cabs: - 4ohms, though it does not explain how the third of the extra cabs is to be hooked up. The matching unit only has two output sockets.
All well and good if the user is clued up and the impedances of the additional cabinets are known. Vox was clearly sailing with a good deal of hope.
A detail of the cardboard mount of a Thomas wah flexi disk showing that the legend "New from Thomas" was a stick-on over the words "New from Vox...". The grey semicircle with an inset image of a Phantom guitar in the centre of the disk itself was a stick-on too, replacing "VOX". See the entry a little way below (21st March), and more on this page.
Defiant serial number 1198, currently in Spain, now registered. Thanks to Juan for the pictures.
Inside the amplifier cabinet, the sticker of Heslop and Co. Ltd, which was based in Rayleigh, Essex, makers of the box. In company with Vox (JMI), Heslop was a member of the Royston Group of Companies. Its sticker also survives in the box of Dynamic Bass serial no. 1135.
Heslop also made various guitar bodies for Vox.
Defiant serial no. 1198. Heslop sticker dated 15th May 1967.
Dynamic Bass serial number 1135. Heslop sticker dated 12th May 1967.
Below, better pictures of a second generation Wah flexi disc still on its cardboard mount. Note the mention of "Thomas" (the Thomas Organ company - distributors of Vox in America), indicating intended use in the US.
At present, only first generation discs - with no mention of "Thomas" - are known to have come to the UK.
Front and back of the (second generation) disc.
Above,the front of a first generation disc sent to JMI.
19th March (2)
Four more JMI wah pedals added on this page - serial numbers 5182, 5855, 5984 and 7181 - number 5984 still with its original box and instruction slip, pictured below:
Serial number 5984. Thanks to Phil for the pictures. More here.
A new page now available on the Vox "Compact 50", a member of the Compact / Slave range introduced in late 1971. These amps are not prototypes or pre-production models, though they were made in small numbers. At least one picture survives of a Compact / Slave in covers awaiting despatch in the Vox factory (see the page linked above).
Vox Compact 50B, "B" standing for Bass. The suffix "T" was used for treble models.
An early Vox Slave Driver - further pics here. Aside from the amplifier logos, "Compact" and "Slave" are pretty much identical .
Below, yesterday's additions by type of amp and serial number, or serial number range. A second set of updates to come on Friday or Saturday:
Travellers - 1041.
Some updates in progress - these will be itemised and linked on this page, probably tomorrow.
"Vox Sound Equipment Limited" Dynamic Bass, serial number 2118, mid 1969, produced before the revision of the preamp circuit (which resulted, among other things, in the presence of one lamp rather than two on the fascia). Other Dynamic Basses are on this page.
The amp, currently in South Africa, is available for purchase - do use the "contact" address above to ask for the seller's details. Thanks to Eddy for the pictures.