Flown in at vast expense from his guitar museum on the Seychelles is the very debonair Mr Paul Day (pictured right), known more casually to Making Music readers as Guitar Guru and to others as the Most Knowledgeable Guitar Expert In The Western World. And so with his favourite cocktail by his side and a team of mini-skirted lovelies to tend to his personal needs, Mr Guru gets down to his answering business. All right!

Raul O'Brien (Morden, Surrey):
"Can you tell me the date of manufacture and which factory my Gibson Les Paul Deluxe, serial number 394540, came from?"

Steve Aldridge (Flint, Clwyd):
"I have a Dan Armstrong sliding pickup guitar, walnut coloured, rosewood fingerboard with Gretsch-style half-moon position markers, one-piece bridge/tailpiece without intonation adjustment, brushed aluminium scratchplate and head, and no serial number. Would it be worth very much these days?"

Jim Murphy (Farlow, Worcs):
"Could you date my Fender Stratocaster, serial number L06310, maple neck, rosewood fingerboard, alder body, trem, and give me an idea of value?"

G Pearce (St George, Bristol):
"Does my Baldwin guitar have any value? I bought it secondhand as a 'Burns' Black Bison although it has Baldwin on the scratchplate. Serial number is 14204."

Brian L Firth (Gainsborough, Lines):
"I have a Burns TR2 serial number 3471, could you date it for me? It has no trass rod, and is in perfect condition. Any ideas of its value, as I've never seen another?"

"From the serial number supplied. I would say that Mr O'Brien's Les Paul Deluxe is circa 1974 and was made at the Gibson factory in Kalamazoo, Michigan, USA. From 1969 the 're-issue' Deluxe model featured small humbucking pickups as used on various Epiphone models, and these give a sharper sound than the standard type — in other words, not the traditional Les Paul tones. Therefore this model can usually be obtained at correspondingly lower prices than the more popular versions.

"The Dan Armstrong sliding pickup solid was launched in 1974 with a matching bass version. The original body styling was similar to the 'See-through' perspex-bodied solid that Dan Armstrong produced through the US Ampeg company in 1969, though the body design was later changed to an asymmetric shape — ie one big horn, one little 'un. The basses met with a more favourable reaction at the time. The 'chassis' (mahogany body and neck) was actually produced by a St Albans-based furniture maker. Although the instruments looked set to be successful, the project was underfinanced (a typical UK trait) and this and other problems led to the demise of the company in 1975.

"Mr Aldridge's Dan Armstrong 341 solid (that's its catalogue designation) is a nice, versatile instrument. As demand is not high, examples can be found comparatively easily at around £100.

"Mr Murphy's Strat is a 1963 model, going from the serial number, and of course would have been made at Fender's Fullerton, California factory. All-original 'mint' (means 'as new') Strats of this vintage are now fetching around £1000, and many are finding their way back to America as demand there is equally high if not higher than in Britain. Pristine instruments are becoming increasingly hard to find.

"The Bison that Mr Pearce bought is in fact both a Burns and a Baldwin — it's what I term a 'transition' example, produced by Burns but issued after the Baldwin takeover in September 1965. This is why it has a Baldwin nameplate. The 'scroll' shape headstock is the original Burns design, not the later 'flattened' shape favoured by Baldwin — and this is the only difference between pre- and post-Baldwin versions. You should find a small sticker on the underside of the main scratchplate which will show the date of manufacture — I would guess early to mid 1965. These 'transition' examples are quite rare and historically interesting. Current value would be around £350 — look after it well.

"The Burns TR2 was made around 1963 and was the world's first active guitar. The battery for the pre-amp is under the scratchplate; the TR of the name stands for TRansistored. There is a truss rod, despite what Mr Firth says — you can get at it under the plastic neck-plate. The TR2 is reasonably common, though as Mr Firth's is evidently in good nick it would be worth about £200. There's a green sunburst version that's even nicer.