Wine. It's said that in a £5 bottle of wine there's about 35 pence-worth of the thing you're actually buying it for. The other £4.65 covers packaging and some profit for the producer, plus shipping costs and middlemen margins and duty and tax. The point is that with any product, there's a minimum threshold of cost to get over before the extra money you're spending starts to pay off in better quality. It's a similar thing with speakers.
The £150 you spent 10 years ago was like the £5 bottle of wine. Most of what you spent went in to just covering the basics of 5 reasonable-for-movie-performance satellite speakers and a sub that could produce a bit of rumble. Don't get me wrong; it was still an order of magnitude better than the speakers in the sort of Samsung/LG/Panasonic/Sony all-in-one DVD/BD home cinema kit, so you made the right choice for your money if £150 was the maximum budget.
Accounting for inflation, the £150 you spent then is the equivalent of £190 in today's market. What that means then, to stand still, you'd be looking at spending £190-£200 on today's Yamaha NS-P41 kit. That works out pretty well because it's forerunner was the NS-P40 kit from 2012 which sold for around £140-£150.
The question then is whether you'd notice a difference spending an extra £100 on something better compared to the NS-P41. In my view you would, but it won't be a sonic revelation.
The Elac Cinema 5.2 kit is £300. You get a bigger and more powerful sub, and the centre and satellites have dual drivers (tweeters and woofers) rather than the single full-range drivers in the Yamahas. What you'd notice is a bit more definition and volume from the sub, and additional detail and extra precision from the centre and surrounds. As a complete package, it would sound a little more composed when things get busy.
The acid test with any system though is music. This is where it would become obvious you're listening to an AV speaker kit trying to do music rather than a music speaker kit doing movies. In general, when speakers do music well, movies are a piece of cake. It doesn't work the other way round.
The Wharfedale kit is better again, but it's still movie speakers. Coming at this from the other end, Monitor Audio's Bronze 2 (Br2) are Hi-Fi speakers that also do well for movies. In the same vein you have Dali Spektor 2, Wharfedale Diamond 220, Mission LX2.
The Monitor Audio Br2 and the BX2 before them are big by bookshelf speaker standards. The 6.5" bass drivers plus cabinet size and bass porting means that they put out quite a lot of bass compared to their peers. My guess is that with a pair of these you could retire your sub because it would be outclassed. They're exciting to listen to as well. There's a lot of drive and energy in the sound.
Before we get too carried away though, I'd temper that by saying that they do need a bit of space around them if they're to avoid sounding boomy. These are not speakers that would live well stuffed in to the corners of a room. Also, the top end is a little forward. It's not harsh, but you wouldn't want to partner these speakers with a thin-sounding AV receiver. Fortunately your Yamaha is fairly neutral. A couple of big plusses in my book are that the BR2 and BX2 are both 8 Ohm speakers rather than 6 Ohm, and they've a higher efficiency than most of the their rivals.
Efficiency is fairly easy to understand. It's how much sound the speakers get from each Watt of power. Many bookshelf speakers are 84-86dB. A few are 88dB. The BR2/BX2 are 90dB. Compared to a speaker at 84dB, the MAs would sound perceptibly louder. More importantly though, the amplifier wouldn't need to work so hard to produce a decent listening level.
The Impedance in Ohms is a little trickier to get your head around, but it's worth the effort.
The classic way of thinking about Ohms is resistance. The more Ohms the bigger the resistance and so the harder it is to push power through that part of a circuit. When it comes to speakers and amplifiers though, the relationship is slightly different. The amp isn't pushing power, it's the speaker drawing power from the amp. The lower the resistance of the speaker the closer it look to being a short circuit. That's the point where components fry and flash and a bang and a little puff of magic smoke escapes, then silence.
Having an 8 Ohm speaker rather than a 6 Ohm speaker gives the amplifier an easier time because it draws less current, and that means less stress on the amp circuits. This is all a gross simplification because there are quite a few other factors involved, but it will do for a quick and dirty explanation.
So, how would these sound compared to say the Wharfedales?
Bigger, more dynamic, better able to resolve all the individual threads of what's going on within a film soundtrack or piece of music. Better composed at higher volumes. They'll fill a large room more convincingly, and you'll be able to listen to them for longer without fatigue. These are the reasons why you've seen suggestions about building up in pieces as money allows rather than blowing a smaller budget all at once on a complete kit.
Buy the BR2 and Bronze Centre speaker as a set. They'll give you a cohesive and matched sound field across the front of the room. Add a sub and the dipole FX surround speakers at a later date.
Are there any worthwhile alternatives?
Sure. Where space is a bit tighter and you don't mind keeping the existing sub for a while then the Dali Spektor 2 (£199/pr) are well worth a look. Sonically they're a bit sweeter sounding but being quite a bit smaller they don't pack the bass wallop. Buy with the Spektor 2 Vokal centre speaker at £170.
Mission LX2 @ £149 (with LXC centre @ £129) is another good shout. The Wharfedale Diamond 220 are really good value at £99/pr and work well as music speakers. Add the Diamond 11CC centre speaker at £149.
People will mention Q Acoustics and there's a lot of love for them in the forums. There are a lot of models too, with some names being very close to one another. Two close siblings are the 3010 (£89/pr) and the 3010i at £129. The 'i' is the newer replacement and it is physically bigger and does perform better. I think you'd need to hear them to decide for yourself if they're a contender.
Hope this all help
