Reviews : Performance Series P11 Loudspeaker
Australian HiFi W hatmough Monitors has been an icon on the Australian scene since the early 70s during much of which time it was operated as a ‘boutique’ business, producing only very limited numbers of loudspeakers each year. All that has changed. Whatmough recently ramped-up its operation, the first stage of which was to move to a large new manufacturing facility on the outskirts of Melbourne, where it now builds almost all its speakers. The second stage was to establish a manufacturing facility in China, to build a new ‘budget’ speaker line, which it calls its ‘Magnum’ series. Truth be told, this second stage of Whatmough’s expansion plan has caused the company some grief, because some hi-fi retailers are telling their customers that all Whatmough speakers are now manufactured in China. It’s not true. Only the low-cost Mangum series speakers are manufactured up there.
THE EQUIPMENT Even a cursory glance at the P11s will have you doing a double-take, because the tweeter is like no tweeter you’ve ever seen before. Realising that audiophiles using super-fidelity sources like DVD-A and SACD need loudspeakers with far superior high-frequency response than ever before, designer Colin Whatmough is fitting his new Performance Series speakers with a brand new, 35mm diameter dual concentric diaphragm tweeter (a Vifa XT25TG30-04) that pushes response more than an octave further than most conventional loudspeakers, to beyond 40kHz. This is not quite as extended as the tweeter in Tannoy’s Eyris range (which extends response to 88kHz) but given that there’s still considerable debate about the audibility of frequencies above 20kHz (see the article ‘SuperTweeters: Why You Need Them’ on page 22 of this issue), and the enormously high cost of tweeters that extend all the way to 88kHz, 40kHz seems like a reasonable compromise. I should also note that because sound becomes increasingly directional with increasing frequency, some of the benefits of having a response to 88kHz could quite easily be negated by sitting in the incorrect position in the room. Underneath the tweeter is a very competent-looking bass/midrange driver which, when I removed it, turned out to be an Audax HM170GO. This driver has a cast magnesium chassis and a huge unshielded magnet. It’s firmly secured in the 25mm thick MDF front baffle by four hex-headed particleboard screws. Showing Whatmough’s attention to detail, the rear of the driver – a technique that has proved to improve performance. You’ve probably guessed from the model number that the ‘nominal’ diameter is 170mm. I say ‘nominal’ because the chassis is not round, but square with rounded corners. It measures 188mm across the corners and 166mm across the flats. The mounting hole diameter is 173mm. The important part is the moving diameter (139mm) and the cone diameter (121mm), giving an effective cone area (ECA) of 115cm2. The rubber roll surround goes the opposite way to normal, curving inwards instead of outwards (an ‘inverse’ surround), and the cone itself is made from coated paper, so it’s extremely light and rigid, to enable an extended high-frequency response, which is important in a two-way design like the P11. While the driver was out, I checked out Whatmough’s crossover network, to find it’s one of the first I have seen that uses ONLY high-quality audiophile capacitors (all Solens) with not a single bipolar electrolytic in sight, and only a single ceramic resistor. As you’d expect, the coils are air-cored, hand-wound to the exact required value and mounted not only at opposite corners of the MDF mounting plate, to assure maximum separation, but also cross-mounted. Again, there’s that attention to detail. All internal wiring is Via solid-core copper wire, and absolutely everything is soldered: there’s not a spade connector in sight. The rear panel of the P11 is home to the bass reflex port (60mm in diameter and 52mm long) and the bi-wirable speaker terminals. These are very chunky, gold-plated numbers that accept stripped wire or banana plugs, or practically any other type of termination. The cabinet is beautifully finished real wood veneer (my review pair was finished in Bubinga, but the alternative is Black Oak). The front edges of the baffle are cut away to minimize edge effects, but you’ll only get the benefit of this if you operate the speakers without the grilles in place (which Whatmough recommends in its manual). Inside the cabinet, that attention to detail is again in evidence, with full side/side and front/back cross-bracing and all internal walls (save the front baffle) covered on acoustic-grade sheet foam. Externally the speakers are 440mm high, 220mm wide and 300mm deep. It’s a good size. They’re quite heavy (12-kg each) so mount them carefully. The Owner’s Manual supplied with the Whatmough is nothing flash, but it’s certainly more than adequate. I was particularly impressed by the fact that it starts out not with the usual purple prose (‘Thank you for buying our great speaker’ etc etc), but with an explanation of the listening room and how standing waves, sympathetic resonances, room dimensions and room furnishings cann affect the sound of any loudspeaker placed in it. This is excellent advice. I once helped a couple who had purchased a pair of speakers that I regarded as excellent performers. They rang me to say that the speakers sounded awful, nothing at all like they had in the showroom. When I investigated, I found the speakers pushed too close to the rear wall in a room with a fairly low ceiling, placed on unspiked stands on a parquet floor. I moved the speakers a little way out into the room, added spikes to the stands and placed large rugs on the floor in front of each speaker. The difference was not subtle, to say the least. Even I was surprised. I’d been expecting an improvement, but I was not expecting one quite so dramatic as the one I was able to achieve in just a few minutes. LISTENING SESSIONS It is necessary to take extra care when installing speakers with extended response tweeters, because the nature of such tweeters is that they must be aimed more precisely at the listening position than conventional tweeters. I’ve taken to using a laser pointer to ensure accuracy. I paid a bit extra to get one I could fit with ‘sights’, but for one-off applications, one of the small keyring or pen types would suffice. The miracle of the falling cost of high technology means that such a laser will now cost you only $12 to $20! Cheap! The major reason for the emergence of super-tweeters, and special-purpose tweeters with extended high-frequency response, was the fairly recent research by Tsutomu Oohashi of Japan’s Chiba Institute of Technology, which proved that ordinary people can detect the presence of audio frequencies higher than 20kHz without consciously perceiving them as ‘sound’. Oohashi determined this by monitoring brain function, rather than asking questions. The astounding result was that even though his test subjects verbally reported to him that they could not hear the high frequencies he was sending their way, their brain scans showed they were actually hearing the signals. It seems that although one part of the brain was processing the high-frequency signals as additional information, another part of the brain did not recognize the signals as ‘sound’ in the normal sense. (This could explain why there are some people who can actually ‘hear’ sounds above 20kHz. Their brains can obviously make the connection.) Knowing we can hear frequencies above 20kHz is all very well, but is there anything up there? ‘Yes’ says James Boyk of the Californian Institute of Technology. So far, he has proved that oboes and violins have energy above 40kHz and that triangles, trumpets, cymbals can produce sounds as high as 100kHz. He’s currently working on analyzing other musical instruments, as well as the human voice. One problem with all this is that when you’re listening to CD, you’ll never be able to any high frequencies, because the 44.1kHz CD sampling rate means that all signals above half the sampling rate (that is, 22.05kHz) have to be lopped off. This means that if you want the security of a response that mirrors what you’d hear in a live performance, you have to use a wide-band signal, and that means not just a DVD-A or an SACD player and discs, but also special DVD-As and SACDs that have been recorded and mastered using non-bandlimited equipment. (Many of the DVD-As and SACDs currently available are mastered from bandwidth-limited digital sources.) There are, however, benefits in using a ‘supertweeter’ to listen to ordinary CDs. These benefits are that the frequency response is usually more linear up to 20kHz, and the phase response is always superior. In my listening sessions, I started out using ordinary
CDs, based on the premise that these are what most
people will
be listening
to, most
of the
time. It
was my first experience with the Vifa tweeter and
I have to say I was impressed. The first thing that sprang
rather
uncharitably
to
mind
was that Dynaudio
is going to have to re-think the pricing on its admittedly
fabulous,
but extraordinarily
expensive Esotar tweeter, because it sounded to me
(though without the benefit of an A-B comparison)
as though these
Vifas could
give them a
fright in the
performance
stakes. They have a rich, lustrous sound quality,
with the kind of ‘depthy’ air
that means there’s never any thinness to the sound. I thought the sound
was superbly detailed, yet this crispness and clarity was delivered without the
sound ever becoming sharp or piercing. The high-frequency sound was also extraordinarily
accurate, so that the levels of brushed cymbals – as well as of individually
struck bells and chimes – were perfectly balanced against other instruments.
The only caveat on this fabulous performance is that it’s maximally delivered
only on-axis or very close to on-axis. Move too far from the ‘sweet spot’ and
the level of the high-frequency response drops off quite dramatically and the
tonal quality loses a little of its on-axis lustre. What with all the focus on the high frequency performance, I had to remind myself not to lose sight of the big picture, particularly the midrange, since I subscribe to that school of thought which says that if you get the midrange wrong, why bother at all? Colin Whatmough’s been in the game too long to make that kind of mistake, because the P11’s midrange is, well ‘just right’. That is, it’s neither forward nor recessed, but still has that life-like sparkle that shows the raw driver responses haven’t been compensated for within an inch of their lives by an over-zealous crossover network. I am fairly big on adequate bass being essential for a realistic portrayal of any musical performance, and the P11s didn’t let me down. Indeed I was impressed by the extension and accuracy of the P11s – impressed enough to take a closer look at the cabinets (and the dimensions), upon which I realised that one reason for the impressive bass performance was that the P11s are quite a bit bigger than your average ‘bookshelf’ speaker, even though they don’t look big. Not that I’d ever suggest you put these little beauties on a bookshelf. They deserve – or rather demand! – a decent pair of stands, placed in the prime position in your listening room. The other reason is the combination of the bass driver and crossover, which work together very tidily – it’s a very nice bass driver, and I’d say Whatmough is extracting its maximum potential in the P11. For proof of this, just listen to the depthy bass at the start of The Thrill is Gone (Tracy Chapman) or the bass on Van Morrison’s If You Love Me. To hear what the tweeter’s capable of, go no further that the percussive intro to All For The Feeling (Sheffield) with Clair Marlo. This track is also excellent for demonstrating how an accurate, uncoloured top end can deal successfully with recorded sibilance. You hear a beautiful aspirant, but without any ‘spitty’ overtones. It’s also worth paying attention to the great exhaled ‘tch’ effects on this track. These not only sound real but are given real physical depth and solidity by the P11s. Across the midrange, I was taken by the smooth richness of Margie Gibson’s voice on The Song Has Ended, but also by the realistic piano tone of the Mason & Hamlin grand used for the backing. Don’t expect a brilliant-sounding treble – it isn’t a Yamaha or a US Steinway – just appreciate the incredible ‘earthiness’ of the sound. The P11s reproduce piano sound very, very well, and no-where better than on Airto Moreira’s ‘Gods pf Jazz’ where the immediacy of the sound is laid bare, and the percussive nature of the piano made raw and apparent. This midrange richness is not across the board, making everyone sound the same. Sara K's voice is etched more starkly than Margie Gibson's, for example, but the valance is still perfect. On her History Repeats Itself (a favourite, I admit it) I don’t think I’ve heard the percussion sound much clearer, or the individual instrument more detached that I have on the P11s. Finally, for anyone who needs confirmation that super-fidelity recordings are superior to CD, can I recommend listening to the SACD version of Yo Yo Ma’s album ‘Solo’ on Sony Classical SS 64114? It doesn’t matter if you’re not a fan of Yo Yo Ma or the type of music, or even the cello. If you listen to just the opening phrases of the first track (Appalachia Waltz), you will be an instant convert to super-fi. Trust me on this one. CONCLUSION Whatmough’s P11 is a vibrant, alive-sounding speaker system that will have you stacking you favourite CDs by your CD player so you can fall in love with them all over again. If you love music, you’ll love the P11s.
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