As a self proclaimed speaker (and pickup) NUT, I can safely say your g12-65s will very likely hold up very well in a live situation, and you can always tweak your amp if you are missing something once in a band scenario. I scored a Marshall JMP 50 watt 212 combo that had the amp removed years before. It had the original 15 ohm Marshall g12-65s in it and I ran it as an open back 212. That thing sounded SUPERB! And I have never liked open back cabs, but this one was different. I then aquired a 1981 Marshall JCM 800 lead series (1960A) 412 that I got unloaded from the same guy. Man do I wish it had the original g12-65's in it. I had done alot of mixing and matching with different speakers and found I really liked a marriage of the G12-65 tone, and a V30 mixed, in an X pattern.
I had tried the 65's with a few variations of Vintage 30's; The Mesa UK-made v30s, the Marshall Vintage speaker (Stock in 1960AV/BV cabs) and current production chinese V30s. The Current production was my LEAST favorite of the 3, most likely because the other 2 pairs of speakers were very well broken in and the chinese were not and were very stiff. I however feel they would take alot to break them in to the point where I would like them and that would be a true test of patience of the highest degree; Sold them instantly. The Mesa UK-made v30s were smooth and tighter on the bottom end, much better for high gain, and not as grating in the upper mids. More polished sounding. The Marshall vintage speaker was more greenback territory than the Mesa UK-made v30, and a little looser on the bottom, perhaps a touch warmer and less focused. Perfect for pushed blues or hard rock sounds, and still good for high gain, just different.
Through all of this experimentation I learned that, contrary to what the internet says, tone is subjective. You must try it for yourself and see, and throw away any preconceived notions you have of any item and base your opinion solely on experience. My mileage in the speaker world has lead me to my ideal setup:
2 Marshall 412s, one slant and one straight both wired in an x-pattern.
The slant is running 2 WGS ET-65s (The best sounding G12-65 style speaker on the market, more broken in sounding out of the box than the Celestion Heritage) and 2 WGS Veteran 30 (V30 inspired with some tonal improvements)
The straight cab is running 2 WGS ET-65s, and 2 WGS Retro-30 (Another V30 variant, that is tonally closer to the Mesa UK-made v30)
I have found the straight cab to be more boomy through all my speaker swaps, so I opted for the retro 30, which tightens up the bottom end and brings a little more treble to the mix. It worked extremely well to balance the cabs, however that cab remains the most polished and focused sounding.
The slant cab with the Veteran 30's is my favorite cab to run on its own, and is a little more wooly and over all has a tone that is very pleasing without sounding overly hi-fi, and I do like a little bit of "imperfection" in my tone. But as we all know, its great to have options, especially when your hitting the studio.
I know many people or devoted Celestion users, but WGS is a great company, with superb products, for half the price (US dollars) of a Celestion offering. Could be worth looking into.
Hope this helps
