Next job is to build a matching speaker cabinet. I have a 12" British made Grampian speaker from about 1960 it came with a rather rubbish RSC valve amp and was then used with my Selmer Treble 'n' Bass, later it was built into my homemade MOSFET amp.
I was concerned that I couldn't use it because a check with my multimeter revealed it was 12.5 ohms and not 4,8, or 16 which I have tappings for on the new amp. but this is it's resistance during DC reading-direct current and not it's AC (alternating current) impedance which gets higher with frequency (and you can't get lower bass than DC!) To get the correct impedance multiply by 1.3 = 16.25 ohms!Plenty good enough! A 12" speaker is much more efficient than a smaller one just because the same coil is moving a bigger cone and therefore more air and at a mere 15-17 watts I think it'll need this when I gig it in a large hall. (Gary's Club in June!)
So I'm planning on carrying on the black and gold theme and partly to save costs rather than buying proper speaker cloth I will use something thinner this will also give me more choice so I can find something more original than the usual Fender or Marshall cloth and I'll fit bars across it to protect it. This weekend I'll look in my local timber merchant for pine to build the cabinet.
PS Am testing the 12" speaker, it sounds far more open and clear than the smaller one but is somehow less jazzy and has far less bass at domestic volumes. But you should hear it when I crank it up a little......clear punchy defined bass wow! I was a little disappointed with the smaller one at the church evening bcz it sounded boxy.
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