MCRU PWC RECORD STABILISER REVIEW
The PWC record stabiliser from MCRU is a resin puck affair designed to fit over your record spindle when you have a record playing. It is designed to effectively reduce unwanted low-frequency information from making its way to your stylus. Janine Elliot takes a listen for HiFi PiG
MCRU, a northern-UK-based HiFi retailer based in Elland, West Yorkshire, run by David Brook and his partner Joanne, sells everything from fuses and reel-to-reel tapes to DIY cabling, and top-end HiFi separates – “From Mains to Music,” as it says on the box. David has spent over 30 years as an audiophile and music lover, with an obsession with cables that led to the formation of ‘Mains Cables R Us’, known now as MCRU.
Among their massive collection of products is the Harmonix TU-812MX record clamp, coming in at an equally hefty £2,495, designed to deal with the resonances of analogue records. Luckily, at a lowly £149, they also offer the PWC Record Stabiliser. MCRU tells me that it’s not a Puck, not a Weight, and not a Clamp either. So, what is the point of this 325g resin device? Well, basically, this is a rigid polymer device for low-frequency noise to be silenced and not make its way into your beautiful music via the cartridge stylus. A record stabiliser.
I recently reviewed the £10k Seismion Reactio 2, an active unit that removes very low-frequency noise (particularly 1-5Hz) and wrote about the very low-frequency vibration prevalent in vinyl, and whilst we can’t hear it, it still affects the cartridge and therefore the music. Max Townshend did a lot of research into removing this with his clever silicon fluid-filled trough and paddle system that fitted onto the end of the tonearm to provide damping, suppress resonances, and improve clarity and sound quality. My Rock7 turntable works so much better with it in situ. The PWC Record Stabiliser intends to do a similar job but in a much different manner.
BUILD AND HELICOPTERS
You will have worked out that PWC stands for Puck/Weight/Clamp, despite their insistence that it isn’t any of those things! This polymer PWC is quite a complex and solidly constructed device with a central hole that tightly fits onto the platter spindle and with three solid-steel ball bearings on the edges on the underside to fit tightly on to the record, similar to that on the Black Ravioli clamp at £500 which has 16 ball bearings and is half the weight, or even the miniscule 17g HexMat Molekula record clamp at £120 which has translucent spheres on each of the 6 sides. So, there are a number of different ways of trying to do the same job. The ball bearings on the PWC will rotate, but are so fitted that they won’t fall out.
My own turntable “clamps” include the free “Richer Sounds” rubber record flattening puck I received in the 1970s, and more seriously, the screw-in clamps for my Townshend Rock and Pre-Audio turntables, and the more amusing disco-light Lenco weight I picked up at the Munich show this year. The MCRU PWC design is much more serious and actually has its roots in a military problem that arose a quarter of a century ago when they were making sensitive mechanical hard drives to save data-streams fitted under a hovering helicopter! Due to the amount of vibrations spoiling the data operation, they discovered that it was possible to, in fact, dampen the rotor vibrations by fitting polymers to the plate onto which the drives were fitted, so that the vibrations at the rotor frequency were removed. It effectively became a mechanical filter. The combination of mass, density, and polymer Shore hardness (this scale measures a material’s resistance to permanent indentation) creates that mechanical filter which absorbs the vibration effectively. 25 years later and the designer of the PWC wondered if it could be re-deployed as a means of damping the vibrations on a turntable, and so created the product we have here. The PWC has the mass suspended on three compressible polymer towers and comes in a choice of orange or black finish, and these columns conjoin to the ball bearings, providing a rigid path for the LF noise to filter away from the platter, the whole weighing in at 325g to make it work correctly. It needs that mass to work, so on highly suspended-chassis turntables, such as those from AVID and other manufacturers using compliant springs, it won’t be effective. It is therefore really only suitable for turntables that are not freely suspended, so my Garrard 301 or Pre-Audio turntables that are rigidly connected to thick plywood and marble plinths, respectively, would be ideal.
IN USE
MCRU noticed that the use of the PWC direct-drive or heavy idler-driven turntables, the LF information tightened up somewhat, something I would need to test for myself shortly. I tried it in conjunction with several mat designs, from rubber, metal, to cork, each offering slightly different degrees of bass tightening, and reviewed with my LS5/9’s plus WB subs to give me a real chance to hear the effectiveness of the unit in the lower frequencies. The Torus “infrasonic generator” helps to show information on the leading edges of sounds, speeding up and tightening the initial transients.
First on the Pre-Audio turntable, with its large illuminated platter and tangential arm, was ELO’s “Daybreaker” from their ‘On the Third Day’ album. Initially, I put no clamp or puck on the platter, and to me, it sounded like it was before daybreak as the musicians performed more like they were still in bed. It lacked detail, speed, transients, and soundstage. I put on the PWC, and from the initial chord at the start, my attention was riveted to the music, with faster transients and just more detail, especially the solo cello and violin arpeggios. Even the synth broken chords in the middle of the work were tighter and fuller in sound. Left and right soundstage is never good in this album; older LPs were never as well manufactured as they are now to create a fuller and wider sound, but the PWC certainly helped define all the detail. The cymbal crashes in track 3, “Dreaming of 4000”, were tighter, and all percussion clearer in “In the Hall of the Mountain King”, a spoof on the famous Grieg work.
Another album from my childhood is ‘In and Out of Focus’, with the instrumental track “Focus” from the band Focus, of course. This has great bass guitar and lots of detail, especially in the forward-sounding percussion. The cymbals are brilliantly recorded, and the PWC really helps to keep this and the tom-toms very precise in this, one of my all-time favourite tracks. Everything in the Focus was very… focused. This 9’45” track must have been played by me hundreds of times, but it still performed as well as the day I first played it on my (then) Philips turntable, a testament to the careful setting up and handling of records even as a child. The percussion and electric guitar in this track have lots of energy, supplemented by the 2-manual Hammond L-100 organ that they always used. This might be a cheap alternative to the iconic B3 that featured so much in the 60’s and 70’s, but the speed and detail of the notes were notably good with the PWC in place. The space in the “Happy Nightmare” jazzy number allowed me to really get involved in the music. The low frequencies were notably “tighter” and the initial transients were very quick. The last track is a “Focus” reprieve, and I have always noticed a distortion at one point in the vocals. With the “clamp”, this low-frequency distortion seemed more controlled; it was still there (there’s no Hocus Pocus magic going on here), but it just seemed more focused in the higher octave; the lower frequency part of the distortion simply disappeared.
Finally, to that deep atmospheric start and end to the track “Mrs Tibbets” from Ian Anderson (The Zealot Gene – Jethro Tull). I have used this track recently in a few reviews, so I know it well. The PWC seemed to give a more controlled performance, surprisingly tight and with greater dynamic drive. Percussion and bass lines were clear, and even the high-frequency flute flutter-tonguing was tighter and clearly timed. All instruments felt better placed in this excellent LP, especially the piano arpeggios, flutter-tongue and tom-tom riff in “Jacob’s Tales”. Indeed, all tracks were tighter and better defined.
QUIBBLES
My only confusion was that whilst it has the MCRU logo on the top of this lovely looking unit, there was no indentation for the manufacturer or even the acronym “PWC”
CONCLUSION
I have to admit I have never really thought much about pucks, weights, clamps, or whatever word this unit needs to be defined as. As long as I had something that would keep the record flat and glued to the platter, I wasn’t that bothered. So, to find a £149 device that notably improved the audio by reducing that ultra-low frequency music-inhibiting sound was quite an adventure.
AT A GLANCE
Build Quality:
Well-made polymer construction that looks good on the turntable
Sound Quality:
Tightens the bass and improves detail
Value For Money:
Well worth the £149 investment
We Loved:
Improved imaging and speed at low frequencies
Tighter bass performance
Looks good
We Didn’t Love So much:
Nothing at £149!
Elevator Pitch Review
I have always used a clamp to hold the record flatter and tighter to the platter, but haven’t before explored the idea that a puck, weight, clamp, or whatever MCRU don’t want you to call it, could actually reduce that inaudible low-frequency modulation that affects the arm, cartridge and stylus to alter the music unfavourably. Come in, David Brook from MCRU, who wanted me to hear how a lump of polymer could actually get rid of that noise and improve the music. Did that mean I wouldn’t need the bass-trough on my Rock 7 turntable and not need to spend £10,250 on a Seismion anti-vibration platform? Well, perhaps not, but at £149 this is a very good-looking device that notably focused my music.
Price: £149
Janine Elliot
System Used:
Pre-Audio GL-1102N/Ortofon Kontrapunkt b (turntable); Manley Steelhead (phono-stage); Music First Audio Baby Reference pre-amp/Synthesis Roma 98DC KT88 tube (amplification); Graham Audio LS5/9/Wilson Benesch Torus/Townshend Supertweeter (loudspeakers); Tellurium Q and Townshend cables, Coppice Audio stand and Townshend rack.
