I had a pair of Hs, and now a pair of Cs and although they do have a very similar sound the difference to me is in the midrange; the Hs seem more 'hollow' as Sam said while the Cs seem to have a good bit of upper register mids, they may border on extended high end but to me it's an upper mid 'zing' that just isn't present with the Hs.
Part of the key difference is the isolated speaker comparisons I do, which expose very clearly what I’m talking about. JBL’s are a lot more scooped, but vs any Celestion or even Fane both are subdued/more laid back in the midrange quality. It’s an American vs Euro speaker quality IME that I haven’t found any exception to yet with other US speakers as well like vintage Jensen’s, Cletron’s, Magnatone and others. They just don’t have the midrange quality of celesions or Fane’s (whether that’s good or bad is taste) and the celestions don’t get the killer highs or lows
I get that compared to a Celestion GB or similar, the Altecs seem mid scooped but to me, in the same cab the 120s definitely have that scoop while the Altecs aren't even close to that kind of mid scoop...so, they may 'appear' to me to have great upper mids at least in comparison to the 120s. It's a clear and obvious difference, when they are in the same cab anyway.
Not just a GB, literally any Celestion or Fane, even if it’s a less midrangey Celestion like a newer t75. In that comparison it’s I think more about the quality (hollow) than scooped. Celestion’s just have a more pokey midrange. JBL’s I found scooped more so in the center mids (very) vs Altec’s (and lower), while Altec’s distinctly lack the uppermids more. To clarify, in case we’re off on frequencies, the exact places where a 20w GB grinds and is very aggressive and also Chinese v30’s is the area where Altec’s are probably the most subdued in that frequency range I’ve heard in a speaker and I think a big part of their unique sound like in many RR recordings. Whether it’s techncially still considered part of the center or uppermids, it’s a very distinctive sound of where those speakers are more subdued than anything else I’ve tried so far. The 20w GB’s were cool with it in adding in what they miss, although for whatever as a quad it just was epic as were the JBL’s quads. A whole quad maybe actually shows what I’m talking about more than even hearing one in isolation
My Cs then must be very different than yours. It seems your Cs are more mid scooped than your 120s; since the 120s lack mid mids and Cs lack upper mids? All I hear from the Cs I own are upper mids and high end. Now, the upper mids are at a higher point than any of my other Celestions
Also, do you really feel that Diary of a Madman is a mid scooped tone? Not me, in fact not even close.....
I’ll have to listen to that song again. I think more about Mr Crowley and Crazy Train. They both have that distinct hollow uppermid effect on each powerchord with the rich lower midrange growl those speakers give. Marshall’s of course counteract some of that, but my experiences are what I mean based on comparing it to other speakers (not focusing on the amp or overall sound, but speaker comparisons with all else equal) and I’m also talking more about the mids and uppermids being laid back/not growly/grindy more than I am actually being scooped/not present. Like you said it’s not scooped vs JBL’s, scooped vs celestions, scooped in uppermids vs everything lol
This is what I’m talking about with the altec character of rich growl in lower mid area, hollow/no growl or character in the uppermids (one minute in) :
I mean the whole DOM album, not just the song. When I play my Marshalls through the JBL/Altec cab, it is bright but it's not just highs/lows, it's got a nice upper mid grind to me. But as you mentioned, maybe the cab has more to do with it? It's a killer tone in my setup.
Ah well later I’ll check out the other songs, just for now checked out the song itself. It’s the same thing. What’s going on I think (as I get also with my 72 and Langner through a whole altec quad) is I think you’re pushing all these aggressive mids and uppermids of the amps into them, but the speakers itself are so smooth and subdued in that area that the net result is very creamy, smooth but still present uppermidrange that is a unique sound. I’ll text later a Langner clip I made a while ago through my quad of Altec C’s. Similar type of sound but more angry
Bill Worked for Altec Lansing and bought all the original equipment when they went out. He uses the original machines and all original material to recone. Here is their site. https://greatplainsaudio.com/ Its been such a long time he may have even retired since I spoke to him last, but he was a wealth of information when it came to pretty much anything Altec Lansing. I have had a speaker reconed by them many years ago and it sounded identical to my best sounding speaker I have. I would send all mine in to re-magnetize them just to see if there is actually a difference, but the shipping cost would be ridiculous vs. what it actually costs to have it done.