[silverr1]

I just saw these and found the concept interesting. I own the RM-40's with the foam style smaller waveguides.


Anyone have experience with these? Are they superior to the ones I have? Is there a diy to build these or a seller that anyone is aware of?

[tbrooke]

I have those on my RM-30s and I'm thinking of changing to the smaller style waveguides -- The smaller guides were series II - At least for the RM-30 --

I heard they were an improvement -- but the long slot looks cool  - I am thinking of changing but I'm not sure it would be worth the effort -

I haven't heard of anyone else going the other way

[John Casler]

That photo was taken in Brian's backyard.

That was an earlier version of the CDWG and the guide later to the individual drivers was better designed, and functionally better, as it had less gap between the driver and the Wave Guide.  This meant that there was far less driver energy reflected back to the driver from the WG.

A much cleaner and better sound.

[Bob Stark]

I had a pair of RM30's w/ Auricaps, silver wire, and better, not best cabinets--cherry.  I had the long slot waveguides and didn't like them as well as the bare drivers.  There was greater clarity with the bare ones, and more transparent in my system.  When I bought RM40's, I bought a set of the newer waveguides from Brian, but never used them on the 40's.  Most of those I talked to or read their posts (call it 80%)liked the sound of the newer ones better than the slot style.  It was a crapshoot on the newer style vs. bare drivers--very even in preference.  Looks wise the slot style would be preferred by wives and girlfriends over either the newer ones or bare drivers.  The new ones are supposed to widen the sweetspot.  The drawback on this point is they will send more lateral sounds off the sidewalls.  The clarity would still be a tad greater on the bare drivers, though.  Hope that helps.  I was a VMPS demonstrator in the Chicago area fro the last 4-5 years Brian Cheney was still going.

Bob

[silverr1]

ok thanks for the clarification. I thought this was a newer design. Good to know I have the latest version.

[Housteau]

My RM-V60's came with these slot type wave guides and looked absolutely stunning.





However much I loved the look and wanted them to sound great, they did not.  They completely limited that speaker by robbing it of the clarity, fullness and life it is so capable of.  Removing them allowed a good sounding speaker to become a great sounding one.





I should clarify that I am a two channel listener that sits in the sweet spot and have no interest in how things sound offline.  My choice is to maximize that sweet spot.  I feel that anything less is a compromise.  If you are in a home theater situation instead where you need more even energy into that space, then I can see a CDWG benefit. 

[tbrooke]

I have the RM-30 with the long slit CDWG and I have tried removing the wave guide several times thinking it will sound better and it doesn't. It has sort of a glare and sommething just seems off without the wave guides. This is in the sweet spot - I don't know if my hearing is off or if I am just used to the CDWG. I am going to do some measurements and see what I can figure out

[Housteau]

The RM-V60 is an open back dipole. My room and treatments were built to support them.  I have not heard the RM-30s with, or without that wave guide and cannot say that they should behave as mine do.

[GeorgeAb]

I have the RM-30 with the long slit CDWG and I have tried removing the wave guide several times thinking it will sound better and it doesn't. It has sort of a glare and sommething just seems off without the wave guides. This is in the sweet spot - I don't know if my hearing is off or if I am just used to the CDWG. I am going to do some measurements and see what I can figure out

You are going to get some mid-range attenuation with wave guide on which could explain the difference. So it should sound more forward with wave guide off.  You could sweep some mid-range frequencies (or fixed mid-range frequency) with guide on and off and measure corresponding SPL to find how much attenuation the wave guide provides (probably -2dB). From there you could dial down the mid-range adjustment pot to match the SPL of wave guide on when the wave guide is off. You could also just tweak the mid-range pot down a bit without doing measurements. That said, if you like the sound with guides, go for it.