Mr Bosso, I always appreciate your input, be it positive or 'constructive criticism' lol, and I won't take it personally!
Comments noted re: Sine waves not being true content, that 'real world' content does have harmonics within it, and that empirically evidenced reductions in distortion are not always audible.
Perhaps it is just a case of PPSL or similarly low-THD setups (however they are achieved) being 'cleaner' (either audibly or captured via electronic equipment) because they do not introduce their own harmonics on top of the real world content's harmonics?
With regards to LMS vs PPSL using another driver, is LMS-U short for LMS Ultra, the one that is almost $1k? I know they are supposed to be very clean and play in very small boxes, but they were way over my budget, personally speaking lol
I just thought it would be cool to try something different I have the space within an alcove to play with, the drivers were cheaper than anything available over here in the UK and the amp was shop-soiled so cheaper, so it's not too expensive an experiment.
Thanks for your comments on the Marathon also, they're much appreciated Hopefully the newer tech will start to trickle down into more affordable equipment in the near future as a lot of the big power / small size stuff is still $$$$! A Clone was on my radar but warranty / reliability was my main concern on that front, and I'm not electronically minded so didn't fancy a DIY fix via email across several time zones... lol
Well, I have the first box now in place and wired up! We'll gloss over the fact I'm an idiot and spent about an hour chasing a fault that didn't exist, just because I didn't twist the speakon in properly at the amp end lol
It is running nicely and I've run Audyssey XT32 on my Onkyo 818. First impressions are it is sooo much tighter than my old ported SVS - I know XT32 is supposed to time-align everything, but I think it was struggling with the ported sub. With this being sealed it seems so much snappier, and now the sub blends into the mains rather than having the mains playing and then a sub playing obviously below them.
There is also the added depth I was looking for; the SVS had 16Hz tune and did well but it seemed to lack the lower end 'weight' sometimes. I think I do need to bring the bottom end up in output, though, as it's not quite as weighty as I'd like, so next plan is to REW everything and see if/where output tails off. I think XT32 only EQs down to the system's -3dB point so MiniDSP or SEQSS is on the radar for low-end duties, should I need it.
The amp is only seemingly tickling the -10dB lights even on very loud scenes so I think I need to run some sinewaves and check output through the system to sort out the gains. That said, I set the gain attenuation dial on the amp according to the 75dB requested by Audyssey (although it was 78dB in the end as the next notch on the amp dial brought it down to 72dB) and the dial is at -22dB IIRC, only 2 or 3 notches off the very bottom of the scale, yet seems to be fine. I don't listen to Reference very often (barely ever TBH) so perhaps it's not a surprise that I'm not lighting all the amp's input signal lights!
I can't wait to get the second one in, the cones on just one box are barely moving on even very loud music content so distortion must be minimal (other than that within the content itself ) and on some of the big bass scenes it all seems pretty effortless, with the cones moving perhaps half an inch in each direction, which should reduce with the second one going in.
I think my only issue is the neighbours - the guy downstairs (who is rarely in as he is young and goes out most evenings and weekends) is selling up to, presumably, get a bigger place with his girlfriend, and so far I've seen what looked like a 60 year old woman with her 80 year old mother looking at the place... Kill. Me. Now.
Apparently I also kept the neighbour in the next block along awake the other night, even through my closed double glazing, his closed double glazing, and the concrete block and brick construction of the place... I think perhaps I had the back bedroom windows open, which must have been leaking sound - I always have the internal door closed to minimise treble carrying through the second, front door and into the stairwell, but perhaps it was travelling out through the bedroom windows that were open. I might have to knock it back a bit or finish watching sessions earlier! Although if some granny moves in downstairs, who never goes out and whinges at the slightest noise, I am in trouble... lol At least now I can have a couple of hours in an evening and in the morning when people are all at work!
None of the above covers the PPSL benefits, though... lol but I have a fellow AV person coming round shortly so I will post his opinion up when he's visited!