A Series of Fortunate Events...Birth of OXO

Brian Cheney · « **on:** 18 Aug 2006, 03:21 pm »

About a month ago long-time VMPS'er Dave R and inveterate tweeker John Casler colluded to come up with options for the RM 40 that I have never tried before, namely an outboard crossover and all Bolder speaker wire inside crossover and speaker. Given the 11.5 gauge twisted quad nature of the Bolder, this meant much additional labor.

I didn't charge Dave R enough for this. He said he wanted "the best RM 40's he could get" and would settle for nothing less. He more than got his heart's desire, IMHO.

Outboard crossovers are nothing new here. They're standard on the ST3SRE system and have found application in smaller speakers. My experience had been that the extra wiring and connectors negated most advantage from the elimination of microphonics and other phenomena. Well, at least this time round, I was wrong, a rare admission for me and my various alter egi.

Dave R's 40's, which I will henceforth dub "Supermax" are a revelation (pardon me if this term has been used before by others) in clarity, extension, imaging, definition and naturalness. I have not yet figured out how much contribution the great Wayne Wanaanen/Bolder wire makes overall, relative to the separate crossover. And remember, this pair includes the SR71, CDWG's. TRT caps, mls cabinets and tuned/tweeked passive CD EQ crossovers. But my demo pair of 40's has all this and does not produce the sheer beauty of sound I hear from "Supermax".

The outboard crossover adds $400 to the price of the RM 40 (really ambitious DIY'ers could retrofit in the field, otherwise factory work is required) and the Bolder wire (over 20ft per side) adds $700. I'll make the "Supermax" available--with all options including the TRT's--for $7800pr for those who want speakers that perform at a level well above the rest. And I know there are lots of really fine competing speakers out there now, at all price points and in various driver complements and configurations.

Also, we are now offering "piano veneer" finishes, a deep high gloss requiring artisan finishing here domestically, at a $300pr additional. The look is sensational and a bit distracting compared to the usual satin , but we're just keeping up with the times.

Brian Cheney · « **Reply #1 on:** 18 Aug 2006, 05:17 pm »

I see I mangled Wayne Waananen's name. My apologies.

Roc · « **Reply #2 on:** 18 Aug 2006, 06:13 pm »

Brian,

Many thanks and much gratitude for granting my wish !
Thank you too big John for helping guide me thru this.
I'm also happy that other VMPS customers may benefit from our joint effort.
And don't forget I'm an active owner auditioner, so send people over to hear them.

But I wish you had not written this article.
I wont' be able to sleep for a week now, awaiting their arrival.

Is there any way we can change the name to the "RoccoMax".
Just kidding!

Now if I can just get you to bite on my molded composite speaker cabinet concepts !!

Dave Rocco

Brian Cheney · « **Reply #3 on:** 18 Aug 2006, 06:42 pm »

How bout "THE ROC"??

Or is that taken too?

Roc · « **Reply #4 on:** 18 Aug 2006, 07:41 pm »

Sounds good to me !

Bob Wilcox · « **Reply #5 on:** 18 Aug 2006, 11:08 pm »

Brian

Does this mean the CDW crossover mods for the RM-40s are finalized?

Bob

Brian Cheney · « **Reply #6 on:** 19 Aug 2006, 12:22 am »

Oh yeah. If you want to go to DEFCON 5 (also known as "Supermax"), you can do it as a DIY project or through the factory. Lots of fun that will keep you busy and reward you greatly soundwise.

ka7niq · « **Reply #7 on:** 19 Aug 2006, 06:46 pm »

Quote from: Brian Cheney on 18 Aug 2006, 06:42 pm

How bout "THE ROC"??

Or is that taken too?

The name "ROC" has been used by Talon ... how about "OMC" ?
OMC of course meaning "Outboard Maxxed Out Crossover"
VMPS RM 40's w/FST and OMC ?

James Romeyn · « **Reply #8 on:** 19 Aug 2006, 10:41 pm »

Brian is building my new RM30C w/ all options including the outboard xo, w/ a twist as follows:

Speaker Inputs

3 pairs (bass, mid, treble) binding posts w/ a small hole next to each post. The internal speaker wires pass through the hole, are terminated w/ gold spade lugs, & attach to the posts. The holes are sealed internally.

Outboard XO

Outputs: 3 wire-pairs direct-soldered to the xo components & terminated w/ gold spade lugs that attach to the corresponding input binding posts on the speaker (bass, mid, treble).

Inputs: 2 pairs (bass, ribbon array) binding posts w/ a small hole next to each post. Wires direct-soldered to the xo components pass through the holes & are terminated w/ gold spade lugs that attach to the posts. Also attached to the posts are gold spade lugs from the speaker cables leading to the amps.

The Twist

All metallic binding posts are replaced by nylon screws, washers, nuts & wing-nuts (the screws have heat-treated steel cores for sheer strength). These fasteners act only as a mechanical junction point for the spades described above, with no conductive parts disturbing the signal.

The British Bullet brand RCA plugs are well-known for high sound quality. Their unique feature is conducting the ground signal via a tiny pencil-point-size metallic ball located at the narrow leading edge of an otherwise non-conductive nylon collar. The mass of the ground conductor is nil. There is similarly little conductive mass to Radio Shack’s RCA plug #274-321 (8/$2.99), which also explains why they may sound better than even the Bullets. The nylon binding posts mimic the same intent. Ric Schultz first thought of using the binding post only as a mechanical anchor point for two conductors (no soldering). The Bullet RCA’s gave rise to my idea of using nylon posts.

One last tweak will probably improve the sound as much as the outboard xo itself, or any other tweak. All xo components get potted in clear silicone adhesive/sealant. The L-pads will be covered in silicone except for vent slots. The improvement experienced in performing this mod on component parts is huge. I can't wait to hear it w/ the recent VMPS improvements & my room & system upgrades. I'd rate it on par w/ at least the difference between the Auricaps & TRT's.

I close by agreeing the SuperDefcon/Supermaxiepads heard at Brian's is the best I've heard the four-d's sound.

Brian Cheney · « **Reply #9 on:** 19 Aug 2006, 11:34 pm »

We shall see what "Supermax" RM30's sound like in 10 days or so, particularly after Jim's many tweek-o changes.

We may never make another "normal" pair of speakers again at this rate.

John Casler · « **Reply #10 on:** 20 Aug 2006, 01:14 am »

Quote from: Brian Cheney on 19 Aug 2006, 11:34 pm

We shall see what "Supermax" RM30's sound like in 10 days or so, particularly after Jim's many tweek-o changes.

We may never make another "normal" pair of speakers again at this rate.

Now that is what I wanted.

Behind the scenes: I have been pestering B, about doing this since I first wrote about the "DIRECT DRIVE" RM Series speakers.

It makes any electronic upgrade (caps/pots/wiring/etc) so easy.

It also makes any VMPS RM Series speaker easily adaptable to either an outboard anaolg X-over, or any of the new "digital" offerings, by having a binding post or connection for each set of drivers. (HF/MF/LF)

I know any of the speakers, I order for "my" system in the future will have the "magic box" set up.

This allows not only "upgrading" ease, but also makes shipping the electronics back to be for "custom tuning" simply a snap. As well, the more tactile types can perform "in the field" adjustments/upgrades/repairs/etc, with far greater ease.

James Romeyn · « **Reply #11 on:** 20 Aug 2006, 02:28 am »

The OXO eases the indispensable improvement of regularly treating the L-pad contacts w/ Caig Pro-Gold. In mono I compared one spekaer w/ this mod vs. the other without; huge difference.

The following tweak is do-able, but is messy in the case of service: Gasket tape seals every driver to the baffle. The tape adds a spring effect, damping transients. The tape can be replaced w/ clear silicone sealant. Eliminating the spring effect improves clarity.

The following is too much work & has some risk: A wood dowel of appropriate diameter is installed behind each driver. A T-nut goes on the end of the dowel toward the driver. A machine screw & locknut goes in the T-nut. The screw is adjusted & locked where it just touches the driver magnet, minimizing rearward driver movement when the diaphragm moves forward. Screw location must be carefully chosen. Too far in eliminates the potential advangtage. Too far out can bend the driver frame when the mounting screws are torqued, or an air leak could result at the mating surface. Done right a huge upgrade, similar to above tweak.

John Casler · « **Reply #12 on:** 20 Aug 2006, 02:32 am »

Further Thoughts

While B, and I have been working on this project for "The ROC", not all the loose ends are totally cleaned up.

I will post the pricing for the "stock" 3 input 2 output version soon, however we will also have a 3 in 3 out version for those adventurous individuals, who live on the edge of "Tri-AMPing".

Just imagine a sweet tube amp for the FST, with a richer tube or SS for the Neos, and a POWER HOUSE, high amperage, bass quality, amp for the woofs.

Now that is a speaker that would make a "SONIC STATEMENT".

Maybe we should call it the "SONIC STATEMENT" RM40???? RM40SS for short

John Casler · « **Reply #13 on:** 20 Aug 2006, 02:33 am »

Quote from: RibbonSpeakers.net on 20 Aug 2006, 02:28 am

The OXO eases the indispensable improvement of regularly treating the L-pad contacts w/ Caig Pro-Gold. In mono I compared one spekaer w/ this mod vs. the other without; huge difference.

OXO = Outboard X Over

I like it

John Casler · « **Reply #14 on:** 20 Aug 2006, 02:37 am »

Quote from: John Casler on 20 Aug 2006, 02:33 am

Quote from: RibbonSpeakers.net on 20 Aug 2006, 02:28 am
The OXO eases the indispensable improvement of regularly treating the L-pad contacts w/ Caig Pro-Gold. In mono I compared one spekaer w/ this mod vs. the other without; huge difference.

OXO = Outboard X Over

I like it

Pretty soon we'll have the whole Alphabet (figured I better say it before some wiseacre cam along)

James Romeyn · « **Reply #15 on:** 20 Aug 2006, 03:13 am »

John
A slight deviation from the thread: Have you ever heard a nice 300B SET on just the FST? My friend brought over the 300B (8-11W) he built for a very affordable sum, well below $1k I'm sure. At the time it powered the entire ribbon array on RM2 spirals. On peaks it ran out of juice. This was frustating, because to this day it was the sweetest reproduced treble I have ever heard, absolutely haunting in its realism & seductive qualities. You could visualize finger smudges on the cymbals. Everything I've heard since or before pales.

The current FST is probably about 6-8dB more sensitive. That 300B SET on the FST would be magic indeed.

BrunoB · « **Reply #16 on:** 20 Aug 2006, 04:15 pm »

Quote from: RibbonSpeakers.net on 19 Aug 2006, 10:41 pm

...

One last tweak will probably improve the sound as much as the outboard xo itself, or any other tweak. All xo components get potted in clear silicone adhesive/sealant. The L-pads will be covered in silicone except for vent slots. The improvement experienced in performing this mod on component parts is huge. I can't wait to hear it w/ the recent VMPS improvements & my room & system upgrades. I'd rate it on par w/ at least the difference between the Auricaps & TRT's.

...

Hi Jim,

I used non hardening modelling clay instead of silicone, way less messy. This is a tweak described by Frank Van Alstine in 1982 to reduce speaker cabinet resonances and to damp turntables and phono cartridges.

Cheap modeling clay can be found from Dollar Tree store or Michael's :
400 gr for 1$, brand: roseart if I remember correctly. Warm up the clay in the oven before applying: it sticks better and is easier to apply on the crossover parts.

Bruno

James Romeyn · « **Reply #17 on:** 20 Aug 2006, 05:21 pm »

My sources have tried both & swear by the silicone, though the clay will benefit & is (probably) less of a mess. I'll have to consider the clay before I go nutz w/ the goop! Thanks!

Bob Wilcox · « **Reply #18 on:** 22 Aug 2006, 11:33 am »

Brian

I was going to email you these questions, but thought you answers will be of general interest. Here goes:

My questions are intended to learn more about what is being offered and if a field implementation will work as well as what the factory would do on new production. Although I am anxious to get a corrected crossover for my CDW, I am also considering other mods and and trying to determine the best overall course of action.

Perhaps it is too early for you to finalize the details but my questions are:

1.   Will this eventually be offered as an in-field swap (you send external crossover and customer returns original parts)?

2.   Will the customer be provided with premounted binding posts on a replacement MDF board or just the binding posts?

3.   Will the factory-provided assembly have wires long enough so that the box rests on the floor?

4.   Can the crossover potting work as well on a recycled crossover versus building a new one from scratch?

5.   Is Jim accurately describing the mod or is his somewhat different than what will be offered.

Thanks

Bob

James Romeyn · « **Reply #19 on:** 22 Aug 2006, 05:22 pm »

Bob
This thread may be the first B heard of the potting & the silicone replacing the gasket tape. I may or may not personally perform both mods & am not expecting Brian to do them. The dowel is a pain in the butt & I'm undecided about it.

I really like that the speakers are empty except for the drivers, stuffing & wires.

In a system & room w/ about 25% the resolving power of my current rig (including the speakers I'm whipping Brian to complete as I type), the potting & driver seal upgrades are startling & stupendous. One can only imagine the differences in a system & room w/ several times more resolving power. The TRL CDP is the cat's meow, the amps, speakers & room all megadittos.

The nylon screws are my personal tweak, I only bought enough for my speakers & a couple spares to be swallowed by the Plant. The nylon should be an audible improvement. I have all four Mouser part numbers & will post seperately if requested.

BTW, I absolutely still prefer the subtle but distinct (but hard to describe) differences in imaging & staging of the 30 vs. 40. But I can't agree more w/ Brian that the OXO made a huge difference for the better. Extremely NOT subtle by any stretch. I pity anyone attempting to remove the parts. I've been in there about as much as anyone except his highness & all I can say is eat your wheaties that morning & do some extra miles on the bike.......do NOT start the project during a stressful week at work....