Dating vox guitars
The cab might even be original - if that's what they had at the factory when the chassis was finished, in it would have gone.
If you want an exact year, you could try the vintage guitar forum though I've not been there for a while so I don't know how active it is these days. Check this link out: The VOX Showroom - VSEL Vox AC-30 Top Boost Amplifier But then the larger vents came in the Birch-Stolec era, so your amp could be a transitional model - not the absence of bell covers for the speakers: there's always the possibility that the amp is one era and the cab speakers another, like you said.
Yours has a few part substitutions - I don't think the Power transformer looks original (is that a date on it?
), and various caps and resistors have been replaced over the years.
In creating the amp that would ultimately fit the bill, they simply doubled the two-EL84 output stage of the AC15, added a GZ34 rectifier and larger transformers to provide adequate power and output, and the AC30/4 was born (the 4 denoting its four inputs, two each for the Normal and Vib-Trem channels).
The increased power made it a more versatile and more rocking amp all-round, which is actually capable of putting out more than 36 watts in good condition, and it quickly became the flagship of the Vox line.
Drawing upon nearly 60 years of tube amplifier design, the all-new AV (Analog Valve) Series from VOX offers players a full palette of authentic amplifier sounds via eight, all-analog pre-amp circuits .