I think this statement is true but it helps to understand where exactly the blame lies.
It's not the speakers, especially Saras and Isobariks. Kans are hard to get working properly but are very good with complex music. Saras are difficult for totally different reasons but are ridiculously musical and forgiving once working. Naim amps, yeah a bit. They had a bit of a glaze to them and got shouty when pushed but they are not tripped up by complex music.
When looking at the LP12 you need to break it down as the deck itself is coloured but very forgiving. Its warmth is rarely an unpleasant addition. Early incarnations can sound rather soggy and lose the plot, especially at the bottom end, but it's very easily fixed with a few updates. Sub-chassis is the fist thing I'd hit as it's a biggie. The old bearing is fine with a good sub-chassis but generally the deck is good at any type of music. Just needs a little stiffening up.
By far the biggest issue, and one that few people identify, is the Linn arms. Yes, once you update the rest of the deck they are better but they are not neutral devices. Swap in just about anything else, an Aro or a Rega, and suddenly you can play all your records. Sure, they sound impressive with the right recordings but it isn't worth it. Personally I wouldn't go as far south as an Aro but a good Rega is a nice sweet spot that gives you nice fluidity and musicality while retaining just enough of the Linn fireworks to not be boring on Rock.
So this was a genuine problem but it's easily fixed and it's worth keeping the LP12 while doing it. Much better to retain the sweet yet involving Linn in the game rather than get a dull Giro or clinical Pink or Roxsan.
Been thinking about this and it’s probably pretty difficult to say exactly what caused certain issues without really extensive auditioning and different opinions. (we are taking abut the Classic Linn/Naim combo being good with simple music but falling apart a bit with more complex stuff)
I’ve personally always liked the Linn arms best and the Ittok is still my favourite overall as the best all rounder. It’s musical and big sounding but has enough detail and precision. Not the best by any means but enough. It’s similar but a bit less forward and is more natural sounding than the Ekos IMO (tried the Ekos mk1 twice and mk2 once, Not tried the SE yet)
I also tried the Aro (twice), Nima, and PU7 and they had some good ponts but
I preferred the Ittok (and Ekos) overall to all of those as the better all rounders. Now I haven’t tried a Rega on the LP12 yet but might do one day. I heard the Roksan Tabriz might work well too.
I would not personally describe the Aro as an all rounder compared to an Ittok or Ekos. I think the Linn arms are better all rounders. The Aro has far superior midrange purity and definition for sure, superior to the pivoted arms , but it’s got limited extension at both ends and a somewhat glassy sound that can get a bit clinical and tiresome. I found it horrific sounding on a cirkus LP12. I could only manage to listen to it on a Pre cirkus deck (many people agree with that), where the bigger midbass of the turntable filled out the lean lower end of the arm a bit and the sweeter precirkus top end of the deck helped the sound be less clinical and more musical. Tried the Aro twice. Same story each time although I chatted to Naim and they sent me a kit for the second one that is a kind of grease which is supposed to get rid of any air bubbles and is supposed to improve things, but I got rid of the arm before I tried it, unfortunately.
I know some people love the Aro but I’m not one of them. It’s a personal thing. Carts I tried were a Troika, Karma, Klyde, MC20 super and standard DL103. The Troika sounded best, so no surprises there.
I’ve still got a Nima and that’s not as pure sounding as the Aro in the mids but I prefer it overall. I personally think it’s a better all rounder. It sounds less constricted in the top end to me. I know some people prefer the Nima too whilst many others prefer the Aro.
I don’t find the LP12 with an Ittok or Ekos limited to a particular genre, and find it decent with complex material. I think it does a pretty good job with everything overall and I’ve found those arms to be the best compromise. That combo isn’t the very best on various genres but certainly good all round. For ultimate bass impact and dynamics for certain records a DD or idler deck is better for sure.
What I was talking with different spec LP12s was more to do with records from different eras. Digital 1980s records that sound thin and bright sound quite different to modern records and I prefer those on a pre cirkus deck.
With the older pre cirkus/Naim Combo, some of the issues might be down to the earlier Naim amps as you’ve suggested. There is the glaze you mention and I think they can emphasise some things in simple music that might make you like the sound more with that kind of simple material, and the same effect maybe starts to sound a bit unnatural and exaggerated with complex material?
A pre cirkus LP12 might not be quite as detailed with complex material as a cirkus or Karousel bearing LP12 with solid subchassis/armboard but it’s still quite decent in my experience. So I’d probably point the finger more at the earlier Naim amps rather than the Linn arms. I could be wrong though and as I say it’s difficult to tell without more testing and options.
I’ll try a Rega or a Roksan Tabriz one day and report back.
Ah just remembered that I did try out a tricked out Rega on an LP12 before, - one of the best Audiomods arms about 10 years ago. Good detail but I still found the LP12/Ittok or Ekos Combo much better all rounders and more to my liking. More weight to the sound but enough detail was retained. I also had a PU7 at the same time and found that had the most weight and scale of all of them but lacked the the detail and focus of the Linn arms, and it also sounded a bit too dark and bloated to me. I know others love the PU7. The one I had was an extremely early model so I suspect the later ones are better.
I had an Ittok, Ekos mk2, Audiomods and PU7 at the same time.
I had the Nima and Aros at different times (but each time had an Ittok to compare to).
Sold on the Audiomods and PU7 reasonably quickly. Stuck with the Ittok, although I have also lived with the Ekos mk1 before for quite a while and there isn’t that much between them.