Hi Antonio! I'm gratified to hear that you appreciate my (slightly droll!) English sense of humour & equally that you find my posts, which are based upon a lifetime's interest in music reproduction which started in my teens & has continued unabated up to my present rather advanced age of 62, helpful.
I also note that you yourself have a clear sense of what you like, whether it be drinks or recorded musical offerings! Now turning to your actual question about loudspeakers! My B&W 805S stand-mounts are the baby brothers of the 800/801/802/803/804 range of floor-standing B&W designs (they actually use the 800D model in the famous Abbey Road Studio #3, which has been the source of many excellent classical & contemporary recordings over the years. They also use pure Class A amplifiers from the Canadian manufacturer Classe to drive them, which are of course fabulous bits of kit but come at an equally fabulous price, lol): all of these designs are based upon the extraordinary B&W Nautilus loudspeaker (do check this beast out on Google images if you haven't seen one - it is definitely a modern work of art in itself... ). I haven't had the chance to hear a pair of these, but I am assured that they sound as good as they look! They are a 4-way active design, & the most unusual shape initially obscures one's realisation that the loading of all 4 independently-amped drivers have a transmission-line loading. Incidentally, B&W's trademark "outboard" tweeters all use a transmission-line loading, hence the tapered shape of the pod. Because they only operate at HF, the transmission-line does not need to be very long to give an acceptable practical approximation to the theoretical infinite transmission-line required by speaker design theory. OTOH, the single LF driver in my speakers has a bass reflex loading, which comes with advantages & disadvantages over the sealed-box "infinite baffle" alternative. The up-side is that *-if-* the designer does his work well in terms of matching the reflex port length, shape & location to the electrical & physical characteristics of the driver, & to the shape & internal volume of the enclosure, the LF extension of the loudspeaker can be extended by in-phase resonance from the port - indeed, eventually ALL of the LF is supplied by the port whilst the driver itself is constrained by the mechanical impedance of the cabinet (this is completely separate & different from the electrical impedance load of the loudspeaker which the amplifier sees... ). Obviously, you can only take this so far with a relatively small stand-mount enclosure & so the LF response of the speaker eventually begins to roll off, & within the audible range of much music programme material which is why having a *-good-* subwoofer (or even better two, as previously explained) can improve the musicality of your system. The most significant down-side is that, no matter how carefully designed they are, you will get more LF non-linearity (distortion), although this is not at a acute range of human hearing. Also, when they do finally roll off, they go at 6dB/octave which is twice the rate as for a sealed box design. A 2-way speaker is simply one that has a single crossover frequency around which the programme material begins to be directed to one driver (or sometimes in the case of the LF range, a set of drivers all doing the same thing) or the other. The precise location of the drivers in any loudspeaker with respect to each other is absolutely critical to achieving good sound because the designer needs to avoid interfering phase effects arising from the physical separation of the drivers - because the crossover frequency is going to be smack in the middle of the most sensitive range of human hearing (unlike the reflex port loading discussed above which only comes into play near the lower end of our hearing capability at which we are less discerning by nature's design of our ears. So the best approach is to "keep things simple" & the stand-mount design which will usually only have 1 HF driver (tweeter) & 1 LF driver (woofer) follows this maxim: this is why good stand-mount designs often provide the most accurate sound-staging (stereo image), usually better than that achieved by larger floor-standing designs which usually have more than 2 drivers... And why they are well suited to smaller rooms! The crossover in a passive full-range 2- (or more) way speaker is exactly that: passive. IOW, it is driven by a single amplifier & has the job of separating the frequencies between the drivers without the assistance of any separately-powered circuitry containing semi-conductors (valves, transistors or integrated circuits): so it will consist of a combination of resistors, capacitors & inductors only. Again the best advice is "keep it as simple as possible, but no simpler" - it has to help to suppress unwanted phase effects arising from the physical separation of the HF & LF drivers, so the designer may not choose the very simplest design but rather go for a quicker roll-off either side of the nominal crossover frequency. This is a highly technical design issue for the speaker designer & consists of trying to find the best compromise (which in itself is a subjective issue) usually through a process involving multiple iterative prototypes before settling on a final production design. But you also have your own musical taste & ears, so you should listen to a variety of speakers until you chance upon a designer (or brand) which has already settled for the same sort of audible compromise that you would be prepared to accept yourself when endeavouring to "suspend your disbelief" that these 2 boxes are really making music... By contrast, subwoofers are always active, that is to say they are mains-powered & contain active electronic crossovers & often DSP to extend the lower frequencies by boosting them prior to amplification by their in-built & generally very powerful Class D power amplifiers. The DSP is the main reason why the amps need to be so big. The active crossover enables them to present such a high input impedance that you can connect them to your amplifier speaker terminals (or to the terminals on your speakers themselves if it makes the wiring tidier) *-without-* this having any discernible effect on the sound from your full-range speakers (with which they are now connected in parallel). Most decent subwoofers will have both high-level (amplifier speaker output level) & line level inputs. Which you use shouldn't make a difference in theory, but the line-level input is really intended for use with a multi-channel A/V amplifier with a single (mono) subwoofer output which is controlled by the master volume control. A few stereo amplifiers have a variable level sub-woofer line output (& even fewer, e.g. the s/hand Pathos Acoustics INPOL-2 which I'm actively chasing as we talk, have one for each channel). But they do not filter out the extreme low frequencies from the signal passed on to the power amplifier stage (which a multi-channel A/V amplifier will do) in case you have BIG floor-standers or listen exclusively to string quartet music & elect NOT to use the subwoofer outputs... I have a pair of B&W PV1 subwoofers, both of which I acquired s/hand. When I bought the 1st one around 8 years ago, it was still a current model so I had to pay £700 for it (still £250 cheaper than a new one!). However the 2nd one which I bought this year & was made quite a bit later than my 1st one, only cost £425 because B&W now sell the PV1D model instead. Of course the older model still works just as well as it ever did. Apart from reducing the on-board power from 500W to 400W, & restricting the finishes to black or white (the PV1 also came in silver, which is my preference since it matches the colour of the stands for my 805S's), B&W have added pre-sets to match the subwoofer to a number of their full-range speakers (although not mine - they are also long out of production) & a remote control for fiddling with the settings whilst you're listening! I maintain that *-if-* you take the time to set your subwoofers to integrate with your full-range speakers properly in the 1st place, there should be no need to do this, & have it pegged as a marketing-inspired "innovation" of no real use. The PV1's are not the cheapest decent subwoofers around, but they are quite pretty (being spherical), compact & have opposed aluminium-mica 8" drivers in a sealed enclosure which are compact & lightweight - as a consequence they are very dynamic & musical. By using 2 of them, albeit in full stereo mode, the 4 x 8" drivers have the same surface area to rattle the air in my room as a single 16" cone would have, but *-much-* less cone mass to start & stop (not to mention no cone break-up since they're metal, lol) so the final effect is very musical & seamless. If I crank my system up sufficiently there is ample power to make the metal RSJ's in my concrete ceiling resonate - I do try to avoid this level of self-indulgence (whenever possible... ) since the effect would be clearly audible in all 20 of the individual units in my apartment block & it is quite difficult to arrange for *-all-* of my co-residents to be out at the same time. ;) So I would advise that you -*can*- get a decent sound quality with good subwoofers, although I concede that you have to be prepared to fiddle around with their settings initially to get an acceptably balanced & non-boomy sound. Now that it's done, I have a pretty but minimalist system & I can focus my attention on the (nearly!) music which is the point of the whole endeavour. Dave :cool: ------------------------------------------------------------------------ Golden Earring's Profile: http://forums.slimdevices.com/member.php?userid=66646 View this thread: http://forums.slimdevices.com/showthread.php?t=107946
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