REVIEW:Raven AC-3+Davinci+Copperhead


Category: Analog

Please click on the link to see the same review with photos.
http://forums.avguide.com/viewtopic.php?t=3585

Raven AC-1 vs Raven AC-3 vs Davinci Grandezza 12”Ref vs Continuum Copperhead

For 6 months I have very gradually inserted and auditioned the above items in my system.

Up until this, my system consisted of:-
Rega Planar 3
Hadcock GH228 Unipivot
ZYX Universe X-SB
Halcro DM10 Preamplifier
Halcro DM58 Monoblocks
Custom-made 3 way moving coil sealed-box speakers
12” paper woofers run full range, 1 small cap for the Mids, 1 small cap for the tweeters, no coils, inductors or resistors in signal path.
Cardas Golden Ref ICs and speaker cables

I’ve always liked unsuspended turntables.
Or put another way……..I’ve never understood the principles of turntables with suspension?
Sound is transmitted in two basic ways….Air-borne and Structure-borne.
The devious thing about that is that Air-borne can become Structure-borne and vice-versa.
If a turntable is mounted on a shelf bracketed off a solid wall, it becomes de-coupled from the floor for BOTH types of transmission.
The bracketing and shelf (being a material change from the wall), effectively de-couples the turntable from the wall for BOTH types of transmission.
You are then left with the turntable plinth and platter to absorb, resist and dissipate only the air-borne feedback.
A ‘sprung’ turntable plinth on the other hand, will convert both Air-borne and Structure-borne sound into movement!
Now for the life of me, I cannot understand why anyone would want their turntable to move?!

The Raven AC is carefully designed as an unsuspended turntable with features that its rivals just don’t have:-
• It weighs just 50Kg making it possible to sit on a wall-hung shelf…..hands-down the preferred mounting place for a turntable (the Walker Proscenium, Rockport Sirius and Continuum Caliburn are 3 times this weight requiring specialised floor-mounted stands). Even the smaller Continuum Criterion weighs 100Kg.
• It is designed to accept up to 4 removable tone-arm boards thus allowing unlimited flexibility in tone-arm choice and change.
• It can function with 1, 2 or 3 motors which can be added at any time.
What I particularly like about Thomas Woschnick’s design is that no vacuum hold-down is required and he also recommends no record clamp.
These ideas fit perfectly with my philosophy.

When I first installed the Hadcock onto the Raven AC-1 with the ZYX Universe X-SB cartridge, I thought I had made a mistake!
The sound was thin with little mid-range, no depth, very narrow soundstage and generally uninspiring.
It took a good 30 hours of play for the Raven to ‘run-in’. No-one ever mentions run-in time for turntables but it certainly makes sense that this should occur.
Once the midrange, depth and transparency returned, it surprised me that the bass was neither deeper nor more solid than that of the Rega Planar 3.
Every review of unsprung mass-loaded turntables I had ever read, always leads with the benefits of solidity and depth in the lower octaves.
Instead, for me, the increase in upper frequency energy and detail was the most obvious difference and that could be a result of both mass and more accurate stable speed control.
When I contemplated the fact that the Rega was wall-mounted on a de-coupled cantilevered shelf, it began to make sense that low frequency performance should not be compromised in a low-mass design which is isolated from both Structure-Borne and Air-Borne feedback.

Gradually the real charm of the Raven AC-1 became apparent.
There was a life and energy to the music which instilled excitement. The more I listened the more I heard what can only be described as ‘latent energy’ or ‘potential energy’…….a seemingly ‘stored’ inner life which seemed ready to explode but which never did, so that the anticipation of this explosion brought to the music that gestalt of realism that one feels in live performances.
Listening to ‘The Chosen One’ from Brian Ferry’s album ‘Boys & Girls’, this ‘latent’ energy became ‘kinetic’ and the vibrating sounds exploded across the spectrum.
On Reiner’s ‘Pines of Rome’-RCA Victor LSC-2436, the climactic ‘screech’ of the strings (which previously had guaranteed a slammed door from my long suffering wife), was suddenly decipherable and under control.


When I installed the Copperhead arm on the Raven AC-1, together with the Dynavector DV1s cartridge it became apparent what good tone-arms fitted to good decks, could bring to the sound (please be aware that this first sample of Copperhead was an early production version with some quality control problems and its installation on the Raven was a compromised affair).
Although it took over 100 hours for the Copperhead’s arm cable to burn-in, more precise control over the low frequencies and a supremely more detailed retention of all the extra energy and information in the higher frequencies supplied by the Raven was the Copperhead’s contribution.
Suddenly the ZYX Universe (which I suspect I like even more than the DV1s) could not realistically compete mounted in the Hadcock GH228.

The Davinci Grandezza 12”Reference and the Continuum Copperhead arms could not be more visually different.
The Copperhead is like a McLaren F1 Racing car with its dark glossy curved profile hunched over the platter appearing to have been designed for speed or forces related to rocket-science whilst the Davinci is like the Bugatti Royale….stately, elegant, perfectly proportioned and luxurious with its Cocobolo wood arm wand and its 24K gold-plated double gimbel bearing structure.
If they were both designed for the same function?.........they surely couldn’t both be right?


The Davinci must nearly be the easiest tonearm to mount and adjust.
VTA is easy (but not on-the-fly), VTF is crude with no micrometer adjustment, anti-skate is a simple magnetically-functioning screw-in device whilst azimuth is not adjustable (the machined headshell and fixed gimbel bearings deeming it unnecessary).
The Copperhead on the other hand is probably the most complex and difficult arm to mount and adjust that I have ever experienced (I still have not managed to correctly install the anti-skate mechanism).


On mounting the Davinci Grandezza 12”Ref on a separate armboard of the Raven AC-1, even without arm-cable break-in, the extra bass provided by the superbly accurate sapphire double gimbel bearings together with the slight warmth provided by the Cocobolo wooden arm wand added to a relaxation in sound that was purely addictive.
It was clearly superior to the Copperhead in most areas accept in one …..the initial attack of the solo piano.
I believe that the solo piano is the hardest instrument to realistically reproduce from a system within a room.
It is not the recording process at fault here…….it is purely the reproduction chain Turntable, Arm, Cartridge, Preamp, Amp, Speakers.
The Copperhead managed to provide the most realistic solo piano I have ever heard in any system anywhere. Using the 3 finest piano recordings I have heard (Keith Jarrett-The Koln Concert ECM 1064/65ST, Daniel Barenboim-List Sonate h-Moll B minor DG 2531271, Masari Imada-Piano Three Blind Mice (1976), the piano was in the room……and I mean a Concert Grand!
Now I’ve actually had a real piano in the house so I know well how it sounds.
To feel the real piano with the attack, sustain, vibrato and decay……to sense the power or delicacy of the fingertips on the keys….to hear the felt hammers strike the strings and the resulting vibrating tone produced from the sound-board…..all emanating from 2 speaker boxes, is a thrill indeed.
Somehow the Copperhead did it more convincingly.

Finally the 2 extra motors arrived from Thomas Woschnick together with a new motor controller which he had been working on for 4 months because I did not like the size and appearance of his standard one (I like to call this the HF Controller).
He hadn’t told me that he had modified the internal circuitry so I was not expecting to hear much difference to the AC-1.
From the first note of ‘Am I Blue’ (Good Old Days-Rita Coolidge A&M SMX-61722) my jaw dropped and I listened in wonderment.
This was simply not possible……..everything had changed! The entire soundstage had blown through the wall and ceiling constraints whilst the entire frequency range had also expanded in both directions.
These changes were so startling that I was sure they could not be the result of the extra motors and new controller but must be caused by the sudden ‘break-in’ of the Davinci’s tone-arm cables.
A switch to the Copperhead proved conclusive……..the same changes to the sound were present and obvious.
The laws of physics (as I know them) could not in any way explain the total change in sound which the 3 motors and controller had wrought. It was more than the insertion of the Raven itself over the Rega!

One more change was still yet to be affected…….the new Copperhead arm.
The early production model I originally had installed, suffered from both quality-control issues and inexperienced installation. The Davinci Grandezza sounded better in most respects except for solo piano (as I mentioned above).
Little prepared me for what I heard when I placed the arm on the ‘The Well’ Jennifer Warnes (Cisco).
Audio writers for decades have struggled for new words and phrases to describe what they hear as the differences in reproduced sound……..’veils lifted from the instruments’……’hearing details I’ve never heard before’…..’floor-shaking bass’……’liquid highs’ etc.
It is extremely hard to convey aural differences when the reader has no idea what you originally heard!

For the first time in my life, I now felt that nothing was in the path of the actual Master Tape.
There was no record per se that I was listening to. Nor was there a turntable, arm, cartridge or amplification in the listening equation.
What was emanating purely from my existing speakers in the room whose acoustics I knew so intimately was without a doubt, the original Master Tape (or at least that which the Cutting Engineer allowed through unprocessed).
Now I remember hearing Master Tape once in my life before…….it was a school excursion in the early 60s when I was 11 years old and it has stayed with me since.
EMI Studios (I think) in Sydney where the Master was played over some battered speakers (JBL?).
The utter purity, definition and tonality sliced through my body like a revelation which suddenly was being repeated right now ………..and in my own home.


Record after record was played…..long into the night.
Barber-Adagio(Erato ERA9271), Ry Cooder-The Border(MCA BSR6105),Fistoulari-Tchaikovsky Scenes from Swan Lake(Decca), Witches Brew(RCA LSC2225), Brian Wilson-Smile, Mozart-Divertimento KV563(DG 139150) etc.
What has always annoyed me reading audio reviews is when I’m told that a product is so good it will show up all the deficiencies in your system!
In 30 years of hi-fi listening, I have never heard a good product which made my system sound worse?
This is not to say that there is no such thing as ‘system compatibility’ with either components or cables.
But when people tell me that a cartridge is so good it will show up how ‘bad’ most records are…..I know that they are wrong.
However I have always known that there are records which are well recorded and those which aren’t.
I have never questioned this fact.
With the Raven AC-3 and Copperhead arm, for the first time a different reality is revealed.
Does anyone really think that Recording Engineers and Cutting Engineers deliberately set out to release the worst sound they can?......or even that they simply don’t care?
The reality is that the Master Tapes actually sounded the way they wanted them to but the ability of the turntables/arms/cartridges of the time to accurately reproduce this sound from the vinyl was seriously deficient.
I can now hear what those engineers wanted us to hear and almost all my previously poorly recorded discs are finally listenable.
Try the track ‘Alabama’ from Neil Young’s Harvest album. Amongst some pretty nicely recorded tracks on this album comes this ‘sound-from-hell’.
Shrieking distorted thin, harmonically challenged and torture to endure on most other systems, it is finally listenable with the Copperhead.
Then again, try Joan Armatrading- ‘Track Record’(A&M RML52037) where side 1 has a different producer (and is poor) to side 2 (Glyn Johns) which is very good. With the Coppperhead side 1 is finally listenable.


When I first heard the Continuum Copperhead arm on the Raven AC, I suspected that I was hearing a paradigm-shifting break-through in tone-arm design.
Then I heard the Davinci Grandezza 12” Ref and I thought I had made a mistake.

The new Copperhead conclusively proclaims the advent of the new-age of vinyl reproduction.
It is so ground-breaking and astonishing that one can only wonder at the possible improvements that the Continuum Cobra (at 3 times the price) can bring to the table?

Would I recommend it unconditionally?
Unfortunately I cannot.

So uniquely designed from an engineering and technical standpoint is the Copperhead that I am afraid it is the most user-unfriendly arm I have ever experienced. If you are not fully technically competent, (and I mean almost Michael Fremer-like), you will not be able to handle the Copperhead.
To adjust tracking force one has to remove the arm from its pivot and whilst cradling it (because it is still attached to the base via the anti-skate thread), one must unscrew from the base of the arm to release the enclosure of the balance weights which are a series of aluminium and brass washers. Then one has to decide which washer to remove or add to try to get the VTF ‘in the ball park’. You then must replace the arm onto the pivot point being careful to reset the thread of the anti-skate. If you are ‘in the ball park’, you can turn the micrometer rod to fine-tune the VTF but it only has a range of about .25 gm in both directions (even though Continuum say +or- .5gm),so if you run out of adjustment, off comes the arm again and the washers need to be added/subtracted.
I can put up with this.
What I have to this day, still not been able to do is correctly connect the anti-skate mechanism and I have spent over 12 hours on this!
There is something very wrong with the engineering design of this aspect when absolutely no configuration can I make work.
And if ever I get it tricked up to ‘sort of’ function……I have to remove it all to increase/decrease the tracking weight.
The VTA and Azimuth adjustments are manageable and hopefully in the future, Continuum will sort out a different solution to their Anti-skate mechanism?

The records I have mentioned in this review are purposefully not the ‘evergreen’ standard audiophile bunch.
Of course Ansermet-The Royal ballet (RCA LDS6065) sounds spectacular.
But it sounds good on any system and if it doesn’t?.........you’ve got problems.
Eric Clapton-Unplugged (Reprise UK:WX480), Paniagua-La Folia (Harmonia Mundi HM1050), Jennifer Warnes-The Hunter and particularly Ansermet-The Three Cornered Hat (Decca SXL2296) all just stun in their presentation.

But it’s the difficult records that really shine with the Raven AC-3 and particularly the Copperhead tone-arm.
Those records you loved because of the artist or the music, but somehow you never play because of the sonics.
These are the records that you re-discover anew with Raven/Copperhead…..and what a joy it is to be able to glean sonic satisfaction from your whole vinyl collection!

And what of the Raven AC-3 turntable itself?
It seems to just disappear. It allows the differences in tonearms to be instantly discernible. It allows the differences in tone-arm set-up to be discernible but never to the point of bad/good, but rather to good/better.
The Raven basically has no sound of its own. Now I know some reviewers are saying it’s warm and lush compared to other tables but I’ve heard the Continuum Caliburn, the Rockport Sirius, the Basis Debut and the Sota Star Sapphire with vacuum hold-down as well as the venerable Linn Sondek and to me, the Raven is the most neutral.
With its 3 motors delivering an enviable speed stability and its mass and materials allowing it to store a ‘latent potential energy’ which barely restrains the music from bursting through the speakers; this has to be the turntable bargain of the decade.

But I suspect that the development of both turntables and cartridges has reached a peak.
I think that Low-Output Moving Coils are able to extract virtually all the information residing in the vinyl grooves and turntable design with the Caliburn, Criterion, Walker Proscenium, Rockport Sirius and TW Acoustic Raven has addressed all the long-standing inherent issues.

Let me be the first to stick my neck out and hereby declare that the tone-arm is the most important part of vinyl reproduction!

The Continuum Cobra and Copperhead tonearms show that the path to audio nirvana rests squarely with further development of the design break-throughs they have un-earthed.
128x128halcro
Thanks for the kind words Gerry.
I don't think anyone has heard the new TW arm as the first prototype has only just been made to my knowledge?

The DaVinci 12" Ref Grandezza is a hard arm to beat (as it should be at its price) but for half the price, the new Phantom II is a bargain.

If you intend to mount a high output MM/MI cartridge, be aware that because of the lack of shielding for the tonearm wires (due to the plastic construction of the arm), you may experience some RFI hum or buzz with the Copperhead arm.
I did and had to have a completely internally shielded one-off Copperhead made for me to eliminate this problem. This process took 9 months.

Good luck in your quest.
Henry
I enjoyed your excellent review. It was great that you shared the ups and downs on each step you took rather than the normal orgasmic raves we read in other reviews.

I'm seriously considering a second arm now. Your experiences and results with the Copperhead have made me vacillate between the Copperhead and the new TW Acustic arm. Do you have any first hand or second hand knowlegde on results with the TW arm? Just bought the Dynavector DV DRT XV-1t and it will go on the second arm.
If there are AC transformers in that amp, there is a good chance AC vibrations are being conducted through the shelf & Stillpoints. Moreover, an MDF board can be problematic however thick. I have 5" of sand(much more absorbent than MDF) underneath my unsprung TT. The sandbox still benefits markedly from further decoupling. A few simple experiments may disprove theory. This approach has been effective for both unsprung Raven(with Stillpoints) and Scout owners who use both wall shelf mounting & audiophile racks on very solid cement floors.

Lower the stylus on a stationary record and rap the MDF with your knuckles in and around the Stillpoints. If you can hear the thump through the speakers, then your turntable should benefit from further isolation. Try resting the entire TT/motor assy on a 1" slab of slate, with the slate resting directly on the MDF tabletop. Slate has natural CLD properties that surpass thick MDF. Repeat the knuckle-rap test with slate & compare with music. Then, elevate the slate from the MDF self using 5-6 $7 McMaster-Carr springs P/N 96485K125. They are 1-15/16”D x 4”L and use .148” diameter wire ground flat at the ends. They compress 23.7lbs/inch, up to a total deflection of 2.88”. So a 50lb load compresses each spring about half way down and leaves .88” of unused travel before the spring binds. Repeat knuckel test & compare with music.

After spending many thousands comparing the finer points, I suspect you will be surprised how much further $100 will take you.
http://forums.avguide.com/viewtopic.php?t=3588
Dgarretson,
Thanks for your feedback.
Please see the link above for my further explanations on sound transmission.
No further decoupling is required.....it is physics and acoustics. Those who wish to put additional decoupling will WANT to hear improvements. What they may hear could be a CHANGE......but for the worse.
You're right that my set-up would be better if the turntable were ALONE on its shelf......but NOT for the reasoning of ' vibration-generating components'.
These components (apart from the preamp, are generally OFF whilst the turntable is ON, however even if they were all ON,,,,,,the frequencies of their vibrations is so high, that they would never penetrate the 2" thick laminated MDF shelf but if they COULD, they would be absorbed within a few inches (wood is a wonderful absorber).
No....the ONLY reason the turntable would be better on its own, is because the weight of all the other components actually MASS-LOADS the shelf which can make it more susceptible to LOW frequency energy absorption.
But the Stillpoints will STILL decouple effectively.
Excellent review and eclectic music collection. I tasted the sweat that went into setting up that Copperhead arm-- like changing shims under buckets in a DOHC racing engine. My only reservation concerns your confidence that wall-mounting provides complete isolation. There are reports that the sound of an unsprung wall-mounted TT is improved after adding further decoupling. This should be particularly true in your case, where various vibration-generating components share the shelf with the TT.
Halcro,
Again, good work on this reveiw.
I,m going to bring this subject up again.
Down the road you will have to try acouple of stand out phonostages.
One in particular,the Zanden 1200 if you can.
Dear Halcro: There is no doubt that you are very good writer !!!!!

Now, I agree with some very interesting subjects in your very well made review but not so much in other ones.

IMHO and only trying to put the TT review in " perspective " ( and in good shape with you ) I want to comment next:

+++++ " and to me, the Raven is the most neutral. " +++++

well this could be true only if you test/try all the other TTs you name it with the same tonearm/cartridge combination and in the same audio system.

you, in some ways, compare the Rega 3 against the Raven and this is not big deal when the Raven price is more than 10 times the Rega one: of course the Raven should be better.

+++++ " The Raven AC is carefully designed as an unsuspended turntable with features that its rivals just don’t have:- " +++++

and you named that accept up to 4 tonearms and three motors. Well there are other top quality TTs ( that rivals Raven ) that accept 3-4 tonearms and three motors, so the Raven does not have any advantages due to these subjects.

Btw, maybe I'm wrong but do you think that three motors that are three distortion/resonance/vibrations/colorations/etc sources are better that only one source/motor?

I respect your philosophy ( that I can't understand because you don't explain it. ) against vacuum hold down record TT systems but maybe could be good that you ( at least ) try it trhough an Audio Technica ( add-on ) vacuum TT platter-mat. Of course that there are trade-offs in almost any " tweak " that we try but IMHO the quality improvement performance using vacuum systems are well worth its trade-offs, anyway this is your call. and I'm only give to you my advice.

Congratulations, very nice audio system you own!!!!!!!!

Regards and enjoy the music.
Raul.
Halcro,
Thanks for sharing your insights for a great review. A new career beckons.