In-depth review on my Wilson Benesch Curves

I was a very happy owner of a pair of Infinity Renaissance 90 for over 10 years, but for reasons unknown to man the urge overcame me to get something new. The paramaters for the new purchase were the following:

- great sound (obviously)
- small floorstanding speaker (don't have a dedicated room)
- outstanding build quality
- had to work with my modified Forté Model 3 (great sound and the next step up was way out of my financial range)
- had to work in a ~ 25-30 sqm room

So, off to auditions!
I heard the Naim 400s (good, but completely depth-free, 2-dimensional soundstage. KEF 205s and 207s (too much a fun, rock`n roll speaker and too fat sounding. Needs (not bad, but no "got to buy them" impulse, cabinat quality not my taste). Sonus Fabers (nice, but too nice - after the Infinitys I wanted dynamics and whallop; amongst other traits). Martin Logans (not exactly small and too room-picky, fantastic if you haven't owned a panel, but I wasn't sure in the long-term) etc.
To set my "reference", I heard a pair of TAD Compact Reference 1 with all the TAD electronics in a very large room and was blown away! Maybe not the electronics, but the speaker is the best I have ever heard below 150.000€.

Then a dealer had a pair of plain black Wilson Benesch Curves for sale second-hand which I auditioned, took home and kept.

I have had them for over a year now and doubt I will ever buy another speakers.

For some reason the reviews on the Curves vary more than any other speaker I have come across. Some descibe it as lean, tinny, bass-shy and overly mid-range biased, others as full-bodied and dark - strange, but I believe this speaker will reveal the "sound" of your electronics much more than most others and needs to be fine-tuned considerably more than say the KEFs or SFs.
This speaker has no sound in itself, less so than any other speaker I have heard, save the TADs.

I had it running off the Forté 3 mentioned above. This is definately on the warm and seductive side, although having chucked out the fuse and thermal switches, exchanged the caps for higher grade and exchanging all resistors with frightfully expensive, but best-around Vishays, this almost 30 year-old amp beats the pants off any SS-amp 3-times it price - I heard it against a 12.000€ Sovereign and small Mark Levinson Monos - not a chance unless you need sheer watts.

I use a Jeff Rowland Capri pre-amp which I find to be a marvellous pice of equipment - it sounds great! A tad warm, very spacious soundstage and the best micro dynamics of any amplification I have ever heard. And it is built like a miniature tank, has RC, is tiny, offers 2 outputs (more on that later) - a pice of art!

Originally I had a Sony CDP 779 modified by Sony-guru Michael Swoboda from Essen, Germany. As far as I am aware he is the only person on earth to receive warranty backing from Sony for his modifications. Price doubles to triples depending on the upgrades, but what you get is the most detailed and resolving CD on earth - which comes at a price.
The price is constant audiophile/technical listening instead of musical pleasure. Few Cds sound great because this box just exposes every fault. I couldn't listen to half my disc collection!
So, off we go, stumble across the Lector CDP 7, take it home and keep it. What a fantastic music player!!!! I have posted a tread on this so I won't go into detail.

I'll start my WB review here.

One thing the Curves always are is dynamic, resolving and they never sound like a cabinet-housed speaker. The dynamics are better than any convention non-horn speaker I have heard, including a number of active speakers like Backes & Müller, Silbersand, Newtronics, Active Linns etc.)

The resolution is holographic, yet one first thinks the tweeter is capped and the sound maybe dull. It's not! But that Scanspeak Tweeter is one of the best on the planet and won't cringe even if you throw ghastly equipment at it.
The mid-range might.

Whatever the technological aspects of carbon fibre are (not a material I really cuddle-up to) and whatever the secrets of the two Tactic drivers may be; the WB speakers never sound like a box speaker. Especially listening to acoustic guitars I always have the feeling other speakers have a specific cabinet sound. This may be pleasant, but the body of the guitar extends to the speakers some how and is never an own entity. The same is true of piano, which seems to be the most difficult instrument to record and play back in my opinion.

Now on to the sound character traits that need a good measure of fine tuning with electronics, set-up and accesories:

Midrange: Again it is fantastic, but it needs a warm-sounding system to get a good balance between detail and body. The Sony i mentioned never got this right, the Lector was much better, but only after changing the tubes did it fully sooth my soul. To put this in context I will add a few tracks I use as reference below and explain.

Bass: The Curves have one BIG caveat! They have two vented ports and the bass driver port fires down. generally I always prefer closed cabinets - the bass on my Infinitys was always great, even if not super tight and deep)

The bass tends to bloom somewhere around 40-50 Hz and it takes some careful placing of the speakers, the equipment and in my case ultra high-grade cables to get rid of it.
I noticed this right from the start and fed the signal through a Velodyne DD12 sub set at 55Hz. It worked but essentially any subwoofer, even using top quality wiring for the signal back and forth, degrades sound quality foir anything but the bass. The quality of the internal signal-path is just not loss-less.
I then tried closing the lower ports with a tightly bunned towel - works, but too much so.
My Curves are already 80 cm off the rear wall so that couldn't be the problem and I didn't want the front further than 120cm into the room.
What worked was a combination of getting the power amp correctly placed - 35kg wooden block (felt or cork underneath) and one 10x10x2cm aluminium-foam board right under that enormous 1400W transformer (now the single "foot") - very high quality speaker and signal cables that are all on the fast and lean side (only possible because of otherwise warm-sounding components) AND a hard connection to the floor. I am lucky that I have a very solid hard-wood floor directly stuck to the concrete. I took the felt off the spike receptacles and tightened every screw, every bolt on the speakers and spikes and levelled them perfectly.

The result is a bass that is fast, deep beyond the otherwise stated 45Hz and has absolutely no bloom anymore.
I still run the subwoofer, but now set at the minimum 40Hz crossover, run out of the 2nd output of the Rowland and set at a volume of 8-10/100. Usually I can't tell if it is on or off because the WBs now have such a bass extension it only shows up on a few CDs. A neat side-effect is that the output level is halfed so your running the attenuator closer to where is sounds best - 100%.
Get your power amp onto something heavy and solid that dooesn't resonate first, then start fine-tuning!

Soundstage: The soundstage is awesome, any which way. Never the less the Curves tended to sound more forward than my Infinitys (which place it very far back) and I can't relax if the sound is too in-ya-face.
Try fiddling with the setup of your signal and pre-amp component before going for cables. I now have a soundstage that has no room boundaries anymore and is never in front of my speakers (which I don't like, but many do)

Dynamics (again): Buy good power chords! Until a year ago I didn't believe in this a great deal. I now have 3 excellent powerchords adding up to 2000€ new (bought second-hand for a total of 600€) - it makes more difference than signal cables in overall system performance. Leave signal cables for last - I didn't and it cost me dearly.
I believe the macro dynamics of my system are on a par with most horn speakers save at excrutiating volume. The micro dynamics are better and the transient attack on some records, even at low levels, sometimes scares the shit out of me.

Volume levels: One thing I can't do without is good low-level sound. Although I now crank up the volume much more than I used to, because distortion and compression are non-apparent, I listen to music so low at night, I can't even hear it during the day when I firste walk in the room. In contrast to many speakers out there, the Curves wotk nicely at low level (not as good as my Infinitys though - I think it's the vented port design vs. closed cabinet).
On the other end of the scale - for a speaker of this size these things can blow the windows out. It's only a matter of what your power amp can deliver. Mine can't deliver enough to make my ears bleed, but it is sufficient. I never see any driver movement so there is still some way to go.
Having said that - I don't think you should try running the curves with a low-power amp if you want at least a little rock'n roll. They are easy to drive as far as impedance goes, but power is good (I would love a second Forté and go mono!!)

To give you some details on what you can expect them to sound like, here a list of tracks I use to fine-tune my system. I have reduced that number considerably in the past to get results quickly and in accordance to what I find important. Also, I have avoided rarities and collectibles, so I hope you find the odd CD in your shelf.

Dynamics, Soundstage, Cabinet: Sara K and Chris Jones Live: Stop those bells

The micro and macrodynamics on this are pretty top-notch, at full blast the guitar needs to almost hurt, but only almost. Getting Sara K's guitar placed correctly in respect to her voice is not easy - they often sound like one singer, one guitarist. Seperation of Sara K and Chris Jones guitars is also tricky. Well set-up the guitar sound great on the Curves due to the cabinet-free sound - no ring, no colouration:

Alicia Keys: Unplugged - How come you don't call me

Whallop and timing: Probably a bit over-the-top recording, the bass on this track can be really tricky and far to fat. It has got to smack you in the face, but remain fast and light. The timing should make you want to get out of your seat after 60 seconds. Nice vocal timbre too.

Stacy Kent: Dreamer in Concert - Waters of March

Timing, timbre, liveliness: This track can sound too slow really easy if you have overdampened your system. It has to be cute and have some swing and her voice shouldn't sound veiled - really difficult to get this right, I have to say as the character of the entire CD changes massively with setup - and not always for the worse, just different.

Paul Simon: Graceland - Diamonds On the Soles of her Shoes

Voices: Yeah, I know - heard it 751-times. But still a great track to see how many voices you can separate, yet the music shouldn't fall apart. If you have the Remastered one with the unreleased version listen to the bass! I like the slightly imperfect hiss on that - you should be there, in the "studio"

Pink Floyd: Pulse - Sorrow:

Rythm and bass: this is my ultimate track to tune the drive in the lower octaves. It's the best bass-line to tune depth, detail and drive of your system. Pink Floyd doesn't really drive me out of my seat, but this one should make you! If it sounds like a one note samba you need to work your system. It has a melody so you need the right colouration, but it needs a hefty colour which easily means it sounds more like a swamp. It doesn't - try!

Ben Folds - Live and a piano - Narcolepsy

Colour and Whallop: probably not a purposefully good recording, this is the best sounding piano I have ever heard - by a mile. Piano tends to sound too thin and high-pitched on many classical recordings, on this (and because Ben Folds plays it like a Kodo drum) it sounds completely awesome. It's the lowest sound you'll hear from any natural instrument, when he crashes down on it a few times you need to think your neighbours think you just got one delivered home, the audiece is perfectly in place, you can hear him move singing and the whole recording has massive aura - who ever mastered it was kind enough not to filter out the goodies!

Adele: 21 - Rolling in the deep

Macrodynamics, trebles: A bit overproduced, but that drum has got to REALLY stomp - you need to trade dynamic speed and depth/whallop. Much easier than with the Pink Floyd track above. Also, treble is a bit harsh on this, but not as much as..

Florence and the Machine: Unplugged

Otherwise a great recording, they managed to get her voice a bit too loud and due to the fantastic, airy setting in church with a huge echo, it can get you a bit edgy sometimes. I prefer her voice on studio recordings, but this is a good extreme to corner-off your treble performance.

Beach Boys: Concert/Live in London

I am not a beach boys fan, but here, with the older recording, despite low-tech recording, you gotta be there amongst the screeching girls in the fron row, yet again be able to place the guys in scale on the stage. But it can be vicious at times.
Live in London was a surprise to me, thinking they can only do shooby-doo music." Do it again" through "Aren't you glad" show they actually can improvise. You should be out of your chair wondering why exactly. If not, your system is too slow and out of pace.

The The - Mind Bomb:

This is a true masterpiece from the eighties - in my eyes a milestone and one of the 10 most important records in pop history. The liner notes say: Please play very loud, very late, very alone and with the lights very low.
Do it - the sound effects are holographic, almost 5.1 DD, Matt Johnsons voice moves across the room, the bass lines are great and then you get hit by a synthetic whoosh as low as the ear can go. Heard it 300 times and it still makes the hairs on my neck stick up like a cat with rabbies.

Pantha du Prince: Black Noise

The most perfect fully synthetic album I have heard. The sounds are new, all over the place and you can tap your feet. Correctly setup will lift you out of your room onto another plane with nothing more than sounds around you - you should forget your hifi system entirely. If you hear speakers, you haven't got the right ones!

Foo Fighters - in your honour

Opening track on the "slow side", if you manage you get that bass bloom-free you're doing well - took me all the work mentioned above. The voice is also really intimate -almost creepy.

Well, I could go on, but it is time to come to a conclusion:

I doubt these speakers will ever be leaving me again. If I win the jackpot, I'll keep them for the bedroom!

The size-to-performance ratio is amazing, which was important to me. I would suggest no less than 20-25 sqm though, otherwise you are overpowering your room - go for Arcs instead.
The build quality is exceptional, even more so for something made in my native England. The finish and coating of the carbon fibre is immaculate. I would like to have a better front panel surface and also see better screws for the drivers, but that doesn't change the verdict in total.
Limitations arise from the system alone. In RRP -terms I have 9000€ speakers (yepp, the Euro-continental premium), 10000€ components and nearly 5000€ cables and it works a treat! The Curves might work OK with a reasonably priced tube amp if you don't need high volume and super-tight bass, but they need a smooth sounding signal and honour good, fast and lean speakers connects of the highest quality.

... and take the front covers off, will you! They are for protection only, not for sound!

Looking forward to comments and further recommendations.