[warnerwh]

My experience with the taking off of the CDWG the night of Jim's visit, was that the soundstage did not so much collapse but instead it got more diffuse, the instruments/vocals got less defined, there was a blurring of the sound; sort of like when your binoculars are out of focus on the image you're trying to bring into said focus.   I've heard the RM30's pre-CDMG and they imaged fine; though the "hot" tonal character bothered me some; though like with the 626Rs I owned that could be helped by the tuning pot adjusments.

So you're saying that the imaging is more precise and full?  My room is LEDE and my imaging is excellent with my RM 40's.  For it to be better would be pretty amazing.  I'm not trying to sound skeptical of your opinion or Brian's ability especially being a dealer for Vmps. Just trying to gain as much information as I can.  I'm guessing this may be something one need's to experience to fully understand.  After all it's not a common feature.

[RoadTripper]

I have the CDWG ordered for my RM40s and Big B promised Christmas delievery.  I will soon find out for myself.

There seems to be no detail on this product on VMPS website. Did you deal directly with Brian C. on the details? What is the final pricing for the RM40 (including PRs) and shipping?

[KJ]

Seminarian,

Per Brian, pricing for RM40 is $300pr, $84 for new low Q passives and shipping costs.

-KJ

[James Romeyn]

I was previously totally satisfied with my rig.  Now that I'm familiar with the CDWG's effect, I'm less satisified.  The soundfield is splashy & the image focus diminished.  I think this is an inherent design feature of the CDWG, & probably not attainable without it.  

This seems consistent with prior knowledge.  Room acoustics are considered the last big frontier.  People who go to great lengths to improve room acoustics generally swear by it.  The final performance is the result of the room interacting with the speaker's dispersion parttern.  (Does any audiophile rag even publish polar dispersion patterns anymore?  It was a mainstay at Audio Magazine.  Does Atkinson do it?)  

If you make a huge upgrade to the speaker's dispersion linearity (we are apparently talking huge multiples increase in dispersion linearity, performance dreamt of but never achieved in audiophile history), this is similar to or equal to tossing out your room for another.  If you think a huge room upgrade isn't a fantastic idea, what can I say?  Consultants get $1000 for professional analysis of this function, not to mention the recommended treatments.

Where am I going wrong?  The only thing wrong with what I'm saying is that you could accuse me of over selling it, & minimizing satisfaction because of false expectations.  As with every audition of new models &/or alleged upgrades at Brian's, I had no predisposition of the outcome how I'd respond.  The CDWG is a huge & surprising upgrade.

The upgrade would appear to be scientifically & positively identifiable via well known, accepted, & undisputed dispersion pattern tests.  This is not a hocus pocus item w/associated snake oil claims.  I think Brian said a very well known & respected high-end professional engineer & audiophile journalist (I won't say who) has agreed to perform lab tests.  I can't wait to see the results.

[Brian Cheney]

The sonic improvement from Constant Directivity is more than just the 180 degree, sharp-skirted dispersion pattern.

Since on axis and off axis response are now the same, it is much easier to linearize the speaker in a given room, by placement, toe-in, and level control adjustments, or electronically.  Remember off axis response in a first-order filter exhibits considerable lobing, particularly in the crossover region.  The Constant Directivity Wave Guide eliminates lobing, improving fidelity and linearity not possible by other means.

The price you pay is a 1.5dB reduction in midrange sensitivity, which can be compensated for with the level controls which are normally set about 4dB below max output, AND, most importantly, a 6dB/oct rolloff in the trebles above 10kHz, which can be compensated for by various means.
Any one here who hasn't read the Peavey White Paper on CD EQ?

I'm going to hear beta-tester John B's system tonite and will report on my impressions.  He is using RM 30C's with a single Dedicated Sub, and with the CD waveguide installed.

www.peavey.com/support/technotes/soundsystems/horn_eq.cfmhttp://

[warnerwh]

Eliminating first order lobing alone should have a profound affect by itself.  A 180 degree dispersion pattern is actually mind boggling.  

I don't know who's doing the lab tests but I did email John Atkinson some time ago to see if I could arouse his curiousity. CDWG will be a significant step forward in speaker design.  Someone like Mr. Atkinson should be very curious.

[James Romeyn]

Warner
Thanks for stating it with so much pith.  

I'll bet Atkinson ignores anything relative to this company.  He shouldn't but he will.  Some of this is not entirely Atkinson's fault, but most of it is.  I have known Brian personally for over a quarter century.  I have seen, relative to certain persons I will keep confidential, an incredible intimacy & depth of love, possibly not witnessed anywhere else.  I am moved recalling it.  I personally think some of this passion is passed along into his work.    

On the other hand, he might be the antithesis of the Gayle Sanders pretty boy that multi-million dollar full color glossies live for.  One full color SP page must be $50k or more.  You can't fully blame JA that humans want to celebrate humanity, hardware less.  Maybe, with absolute respect & in sincere friendship, this advice could help Brian.  I've seen Brian pour it on pretty well when the mood suited him.    

Danica Patrick did so much good for Indy cars not just because she's an attractive female & a moderately good competitor, but because she's a person, not hardware.

[Brian Cheney]

I spent an hour at John B's listening to various IC's and speaker wire on his system until we found a mutually satisfactory combination, then just listened to music for another hour.

Whether vinyl or digital, classical or jazz, male or female vocal, John's system (based on Bruce Moore tube gear, Marantz CD player and a VPI turntable with Sumiko Black Point cartridge) produced some of the most realistic--why be coy, perhaps the most realistic) residential music reproduction I have heard in the past 30 years.  I can't imagine any audiophile of experience and discrimination finding the sound less than totally enjoyable.

Yes, Constant Directivity contributed greatly to the wonderful quality I heard.  But, as the tweaking we did suggests (e.g. I advanced the speaker level controls from 12 to 12:15 on the mids and from one to 1:30 on the trebles), careful setup pays off bigtime.  The RM 30C only goes to 42Hz, so the single Dedicated Sub really helped by supplying first and second octave bass. We did not apply any "CD EQ" externally.

I can only hope to sound this good in our CES booth, St Tropez 1303, Jan 5-8.

[John Casler]

How can a speaker that many claim has the best imaging and soundstage ever, all of the sudden see the soundstage and imaging collapse?

Well of course it doesn't.

What is being noted here is that the CDWG "adds" a dimensionality that while hard to describe is certainly something you can hear.

I'm sure many will find it will take a bit of time to not only get used to, but also understand.

To begin, it is vitually impossible to do a direct A/B comparison to "with and without", because each would require adjustments to the L-Pads, the PR, as well as to the main volume levels to perfectly match.

What is at play here is an "integration" of frequencies being dispersed, that offer a "spatial perception", or dimension, that can only be attained by the "non-CDWG" version at an exact place in space, in a well treated room.

This "dimensionality" provides an extra element to realistic sonic placement and palpability of a performance.

When this "extra dimensional" stabilizer is removed, you certainly miss it, and that, I beleive, is what Jim was talking about.

So I think it should be known that "all of the sudden" the speakers didn't turn to "lousy" speakers (because they did not) but the extra dimensionality is certainly a quality that when heard is soemething that is missed when you do hear a system that doesn't have it.

Maybe that might explain some of the previous comments regarding what the CDWG does.

I am waiting approval from B, to post a few shots (again in the pre-production stage) of some wave guides for the RM30's.

[James Romeyn]

I must apologize for ignoring the fact that it has been mentioned several times that the CDWG attenuates the mid/treble 1.5dB & adds a first order low-pass slope above 10 kHz.  This obviously prohibits a direct A-B, yet that is what I did twice.  I believe the effect of the CDWG is far different from the above described differences.  

As usual the voice of reason (jc) has spoken.  John what do you think of comparing two pairs RM30C's, each tuned well for a great system, both pairs as close as possible virtually identical (similar thorough burn in, similar production run, etc.), & comparing one pair CDWG vs. the other pair without?

After a potential buyer simply hears a CDWG-equipped ribbon (by itself) & decides the sound is good, it appears the above comparison is the true, final, & necessary test: Unless you are willing to risk return shipping & just have a pair shipped to you to hear it at home.

[BrunoB]

How can a speaker that many claim has the best imaging and soundstage ever,
...

John,

how do you see your Lapel tweak in the context of the CDWG? Do you think you could use your tweak on top of the CDWG grill?

Bruno

[John Casler]

How can a speaker that many claim has the best imaging and soundstage ever,
...

John,

how do you see your Lapel tweak in the context of the CDWG? Do you think you could use your tweak on top of the CDWG grill?

Bruno

Hi Bruno,

Strangely enough, when Brian and his wife Shirley, came down to "surprise me" with the CDWG prototype, they were surpised to see my foam covering about the first 1/2" on either side of the neopanels.

Initially, I had the lapels at the outside edges of the neopanels, and kept moving them in.

However, my goals were different.

It was my intention to "REDUCE" side dispersion, and also baffle refraction.

The CDWG actually is to "increase and smooth" dispersion, so no, the Lapels would probably not enhance the sound.

But that probably will not stop me from "tweaking" and trying it.

By the way, you would probably love my latest "ROOM TWEAK".

I have built a "listening tent" or LISTENING CHAMBER that surounds my listening chair,

It is built of all my speaker cartons, filled with cardboard, packing material, old towels/bedding and sheets, and styrofoam peanuts.

It encloses my listening position REAR, SIDES, and OVERHEAD.

The boxes and ceiling of the "tent" are covered in layers of blankets and the interior walls are 6" acoustic wedge foam on the side and rear walls.

It blocks or absorbs quite a bit of all room reflections.  

The top is totally covered, and a blanket hangs down over the front, so that when I sit down I can see the tops of the speakers, but not the ceiling.

So effectively the main sound I hear is the speaker.


When you first sit down in this "listening chamber" you are amazed at the "Sound of Silence".

It is also great for meditation and a great afternoon nap.

But the sound is absolutley amazing.  Imaging, soundsatge, reality are incredible.

The sound is so accurate, that in some studio recordings, you can hear the acoustic properties of the "space" of each instrument, and how it was damped, and the size of it.

This is the perfect solution for those with a small dedicated 2 channel room.  Rather than treating the whole room, you treat the front wall, use some bass traps, and, and listen within the chamber.

It is GREAT!!

[zybar]

John,

At this rate why not just go with headphones?  

George

[John Casler]

John,

At this rate why not just go with headphones?  

George

Hi George,

I have yet to hear a pair of headphones that can produce imaging, depth, and soundstage, which are the highest qualities on my list.

The listening chamber does that.

However, this room tweak "does" offer the sonic purity of phones without the discomfort, and lack of the above mentioned attributes.

Obviously, it will not work in Dual Purpose rooms, such as HT/living/audio rooms.

It is more specialized to what I call "High Performance" listening.

It is like driving your sports car around the track, rather than city streets.

The results are to be able to enjoy the last bit of performance with less compromise.

[ekovalsky]

John, please post some pics  

[John Casler]

It looks a bit like this, except I now have the front in a matching color.

It is primarily designed to further remove the room reflected sound at the listening area.

It certainly is not a system everyone could use, but for those in small dedicated rooms it is an alternative to attempting to treat room reflections on the walls.

Nearfield listening is stunning in its reality.

[ScottMayo]

And they call it... the Chair of John. The BIGGEST Development ever in the history of history, in Massively Negative WAF !  

I declare it open season on Padded Cell jokes.

 

[John Casler]

For those interested here are a couple photos of the "pre-producion" CDWGs for the RM30's

Please realize these are taken under "factory" conditions and they are all dusty and not fully finished.

The photos are only to give you an idea of the size and shape of the guides.







The top picture is obviously of the front of the waveguides

The Center is of the new "Beefy" cabinet.  Notice the thickness of the baffles, and even some of the "bracing" is shown. Even the Slot looks strong enough to drive a truck over.

The bottom picture shows the cutout running along the NeoPanels for the damping laminates.

These look to be black laquer, but with all the dust it is hard to tell.

[James Romeyn]

John the shroud idea is great.  Someone should produce & sell them.  It certainly appears easier to damp the immediate area around the seat vs. the entire room.  Why didn't anyone think of that before?

[ScottMayo]

John the shroud idea is great.  Someone should produce & sell them.  It certainly appears easier to damp the immediate area around the seat vs. the entire room.  Why didn't anyone think of that before?

This was being done in the 70's, by the occasional audiophile. It's not that it hasn't been thought of - when I was testing out my room, I did a bunch of things that looked something like this, for some tests. But it's not practical for the masses, it rules out anything beyond 3.1 sound, and it's not cheap, or so I expect. Surrounding yourself in 6" of decent acoustical foam takes a lot of foam.

If it could be manufactured in a form that was trivial to set up and tear down, though, it could be a boon to serious audiophiles who CANNOT, for non-negotiable reasons, treat their room.

John's design here is interesting - I bet it doesn't block much below 150Hz, and probably nothing below 60Hz or so - so you're still free to plant a sub anywhere in the room you like. It will block very little from the ceiling - blankets absorb next to nothing and mostly diffuse a bit - so there might be enough early reflection from the ceiling to fill in a little ambience. And of course, that bulk of foam in the center of the room is going to amount to significant "single mass treatment" for the room as a whole. It won't treat the bass much of any, unless maybe the chair is parked at a bass mode, which I kind of doubt. It will absorb significant treble, though. I suspect things sound kind of odd *outside* the Chair of John... but the new C-D design might help fix that.

Hey John, what did it cost to assemble?