Were the original Vox AC15's wired correctly?

[almano]

I must thank fellow ShadowMusic member "nicodemus" for his brilliant work in discovering the true identity of my earlier posted ancient Vox amp.

It is not, as I first thought, an AC15, but rather an odder beast of an AC10 in an AC15 cabinet! How’s that for weirdness?

A very good bit of detective work by “nicodemus” found the perfect references to the AC10 chassis which replicated the photo of the output stage I had originally posted.

Here’s a photo of an actual genuine AC10 output stage for comparison purposes to my original photo.



You’ll probably notice the 100 ohm resistors are a different make of those old carbon ‘block’ resistors you’ll see in my photo – and also that a series pair of wirewounds have been added in the HT line (presumably for a little extra smoothing on the HT line to try to eliminate hum from the amp) but otherwise, the wiring itself is identical.

Note: as a small amendment to those wirewound resistors I've mentioned above, I've just found out that they were included in the later versions of the AC10 - they are 2 x 100 ohm 5 watt resistors. The circuit without those resistors is the AC10 No3 - the circuit variation is: 05/008 and the date of the amp is January 1960. (All this info is on the Vox web site - I should have looked more closely earlier -oh well, we live and learn!)

According to some “Googled info” it seems that the AC10 is a derivative of the AC15, with more or less the same circuit, but it was “limited” with those resistors in the EL84 anode feeds in order to produce a certain “sound” that was very much in favour at the time. Unfortunately I can’t verify this particular statement myself, it’s what others say, but I will say the amp certainly sounds “musical” as compared the somewhat raucous sound of a lot of the amps these days. So, if that really was their intention with the AC10, then I’d say they’d achieved their musical goal.

Anyway, now that I do know the correct amp model I’ve actually got, I’ve ordered the “Service Engineer’s Vox AC10-15-30 manual” from Amazon (it’s sold out at the moment, but more are expected in – I hope!) – and, with any luck, a full referb will see it back to its sonically original status!

Thanks to everyone for your interest in my “odd” Vox AC15 – which wasn’t actually one after all!

Cheers,

Alan.

[ecca]

I've had 3 Voxs in my time and the 'growliest' was the AC 10 that I had.
The AC30 never did anything except get louder and the AC15 ( best ) acquired 'character' the louder it got.