Finally the SR71 option is available for VMPS models

John Casler · « **on:** 11 Aug 2005, 12:11 am »

As I announced some time ago, there is a new optional upgrade for VMPS speakers.

I call it the SR71 upgrade since it has to do with the "Sound Barrier".

As some have guessed, it is the application of Black Hole 5 to the interior of the VMPS cabinets.

B, analyzed several products that are excellent for this purpose and settled on Black Hole 5 as the one he liked overall.

I had it done to my pair of RM30's and the results are excellent.

Brian has just given me the "go ahead" to list the pricing on a couple models, and the rest will follow.

Right now it is available on the RM30 and RM40 cabinets.

RM30 = $240
RM40 = $480

Soon I will post RM2, 626R, and Sub pricing.

But as of today, you can order this option with these two models.

I certainly suggest it as one of the best ways to improve bass, detail (one of my favorite things) and it also cleans up midrange a bit too, by reducing cabinet talk.

JoshK · « **Reply #1 on:** 11 Aug 2005, 02:11 am »

I used the thick whispermat which is very similar to the BH5 and can say that I too confirm that its benefits were very worthwhile in my opinion. I too would say that I found the best benefits in the bass tautness and detail.

The good ole hand test proves that it does lower cabinet resonance in my RM40s, although I don't have the latest uber cabinets. Doing this yourself is a royal PITA though and I would gladly pay someone else to do it. Smelly, messy, combersome. The first time I tried to install some I got a little stoned.

ctviggen · « **Reply #2 on:** 11 Aug 2005, 11:04 am »

Josh,

Do you have to use glue? If so, what type? I might try this upgrade, although I can see it could be a pain to fit pieces of mat through the holes of the woofer/midwoofer. I might do this and the wool upgrade at the same time.

woodsyi · « **Reply #3 on:** 11 Aug 2005, 11:55 am »

Quote from: JoshK

I used the thick whispermat which is very similar to the BH5 and can say that I too confirm that its benefits were very worthwhile in my opinion. I too would say that I found the best benefits in the bass tautness and detail.

The good ole hand test proves that it does lower cabinet resonance in my RM40s, although I don't have the latest uber cabinets. Doing this yourself is a royal PITA though and I would gladly pay someone else to do it. Smelly, messy, combersome. The first time I tried to install some I got a little stoned.

Boy,

What would happen if you sipped some fine sigle malt Scotch as you are working on this? Stoned and tipsy --that will bring back some "fond" memories of the glory days! What brand glue was it? I gotta get me some.

JoshK · « **Reply #4 on:** 11 Aug 2005, 01:23 pm »

You want to use the 3M adhesive spray (spray on rubber cement). Check out the zaphaudio.com site for the thread on BH5 vs. WM and it goes through how to install it.

You need to use the spray outside with preferrably a respirator mask as the spray is seriously toxic. This is part of the pain as the RM40s are big and heavy and awkward to carry outside. I installed the thinner WM on the side walls of the inside of the midrange panels and thick stuff on back besides just inside the woofer enclosure. I first tried to install the side piece with glue applied to the inside of the mid enclosure as one whole piece, I quickly learned that this was not a great idea. After cleaning up....I decided that cut in half width wise made it much easier to negotiate into the spot. Also spraying the adhesive with the foam tilted away from the wall it is to be applied to makes it easy to spray adhesive to the wall and foam at same time without all the mess.

John Casler · « **Reply #5 on:** 11 Aug 2005, 02:37 pm »

Quote from: ctviggen

Josh,

Do you have to use glue? If so, what type? I might try this upgrade, although I can see it could be a pain to fit pieces of mat through the holes of the woofer/midwoofer. I might do this and the wool upgrade at the same time.

The spray adhesive is needed with WhisperMat, but Black Hole and Sonic Barrier come with adhesive backing already applied.

Choose your poison

JoshK · « **Reply #6 on:** 11 Aug 2005, 02:40 pm »

aw...forgot about that. yeah then the cost differential is becoming worth it then.

KJ · « **Reply #7 on:** 11 Aug 2005, 04:02 pm »

Quote from: JoshK

I installed the thinner WM on the side walls of the inside of the midrange panels and thick stuff on back besides just inside the woofer enclosure.

My understanding is that you want to install the BH5 on the wall that absorbs the backwave from the bass driver(s). Given that the RM30M has 2 mid-bass woofers firing towards the back of the cabinet and 1 low-bass woofer firing towards the side of the cabinet, would it be appropriate to cover both? I'm curious if that would that over dampen the midbass since the side wall is 20" deep.

-KJ

John Casler · « **Reply #8 on:** 11 Aug 2005, 07:35 pm »

Although Brian could be more specific, I don't think you can "over damp" the interior of the cabinet. It is subject to ringing, and standing waves also. It is best to do as many (and as much of all) surfaces as possible including "opposing walls" and all corners.

There is no advantage to any of the "reflected" bass energy for any purpose.

In fact, the Passive Radiators are also "much cleaner" when these extra sonic energy reflections are Quelched. So VMPS speakers with PR's stand to gain even more than most other speakers that use the SR-71/BH5 option or internal damping.

The passive radiator responds to, and passes "most all" internal cabinet energies/pressures. Damping them makes a very nice improvement indeed.

While I haven't had Brian try using the "thinner" damping material on the inside of the Neopanel case, (behind the neopanels) before stuffing it with lambs wool. Josh K and I have discussed it and he is trying it. We'll soon hear if it makes a difference.

KJ · « **Reply #9 on:** 11 Aug 2005, 08:35 pm »

Quote from: John Casler

Although Brian could be more specific, I don't think you can "over damp" the interior of the cabinet. It is subject to ringing, and standing waves also. It is best to do as many (and as much of all) surfaces as possible including "opposing walls" and all corners.

Wouldn't this eliminate the need for the sound coat? If so, perhaps this is a better alternative for VMPS subs?

-KJ

Skynyrd · « **Reply #10 on:** 12 Aug 2005, 12:52 am »

I ordered up about forty pounds of Plast-i-clay for my RM40's and put it all over the inside of the cabinets (20 pounds per cabinet), and I added three sets of binding posts for future DSP triamp capabilities. The Plasti-i-clay is a twenty-plus-year old idea I got from Frank Van Alstine's website. The binding posts are from Madisound--about $20 for all six pairs. The binding post area is super-thin and easy to drill through.

Have any of you RM40 owners removed your passive radiators and sealed off the passive radiator hole? It may be a year or three, but I'd like to give that a try some day.

Has anyone added an extended front baffle to their RM40's? Who uses grills, anyway. This would give the planar magnetics a bit more cavity space behind them as well as diffraction benefits.

With the Plast-i-clay in place, "Machine Head" on vinyl just sounds amazing.

Skynyrd

JoshK · « **Reply #11 on:** 12 Aug 2005, 01:26 am »

Quote from: KJ

Quote from: John Casler
Although Brian could be more specific, I don't think you can "over damp" the interior of the cabinet. It is subject to ringing, and standing waves also. It is best to do as many (and as much of all) surfaces as possible including "opposing walls" and all corners.

Wouldn't this eliminate the need for the sound coat? If so, perhaps this is a better alternative for VMPS subs?

-KJ

Not really. You can think of the soundcoat as adding dampening to the walls of the cabinet while the BH stuff helps unload some of the pressure on the walls.

CornellAlum · « **Reply #12 on:** 12 Aug 2005, 01:33 am »

Anyone know where the cheapest BH5 is sold for those of us that would like to do it ourselves?

Thanks!

CornellAlum · « **Reply #13 on:** 12 Aug 2005, 01:51 pm »

Just a quick question. How much surface area does one need to buy for each model, and in my case, 626r's?

Thanks!

ctviggen · « **Reply #14 on:** 12 Aug 2005, 04:30 pm »

Skynyrd,

Zybar added a baffle to the front of his RM40s, near the mids. And I use grills. I find there's only a minor difference between having the grills on and off.

Skynyrd · « **Reply #15 on:** 16 Aug 2005, 05:12 am »

Thanks for the reply, ctvitgen/Bob:

Regarding the "extended baffle". I'm thinking major speaker surgery, not just some foam on the front. I mean, remove all the drivers, and extend each driver out three or four inches by building a new front for your RM40. Give those midranges some backwave breathing room, and the woofers, as well. Then you could angle the 10" drivers towards the center of the speaker. A lot of work, and I've got the following RM40 tweaks to do before I gut the speaker boxes and totally redo them like I just described:

After I first actively biamp the RM40's.

Then triamp them along with some NHT1259 woofers in big sealed boxes.

And a few variations in between.

I'm set for a few years at this point.
Skynyrd

ctviggen · « **Reply #16 on:** 16 Aug 2005, 11:29 am »

Wow, that would be a lot of work! I'll be happy just to add wool and some internal damping! However, I'm also still in an "acoustics" frame of mind -- I'm trying to learn more about acoustics, and I endeavor to see what types of acoustic materials are good, what types are bad, and whether diffusion is useful for a home theater or not. Since I have limited time, modifying speakers (even the wool and damping) is problematic for me. Keep us updated as to what you do, though!

doug s. · « **Reply #17 on:** 16 Aug 2005, 03:36 pm »

Quote from: Skynyrd

Thanks for the reply, ctvitgen/Bob:

Regarding the "extended baffle". I'm thinking major speaker surgery, not just some foam on the front. I mean, remove all the drivers, and extend each driver out three or four inches by building a new front for your RM40. Give those midranges some backwave breathing room, and the woofers, as well. Then you could angle the 10" drivers towards the center of the speaker. A lot of work, and I've got the following RM40 tweaks to do before I gut the speaker boxes and to ...

hi skynyrd,

shameless plug time!

you yust need to sell yer rm40's to someone not interested in tweaking, & buy my kit!

http://forum.audiogon.com/cgi-bin/cls.pl?spkrfull&1129387098

doug s.

woodsyi · « **Reply #18 on:** 16 Aug 2005, 04:30 pm »

Quote from: doug s.

hi skynyrd,

shameless plug time! you yust need to sell yer rm40's to someone not interested in tweaking, & buy my kit!

http://forum.audiogon.com/cgi-bin/cls.pl?spkrfull&1129387098

doug s.

Doug IS SHAMELESS on plugging for his kit.

But it does make sense this time for Lynyrd to buy Doug's kit and build a new enclosure rather than doing surgery to existing cabinets...... Having disassembled one pair of RM40s, I can speak unequivocally that a new kit would be easier to work with if you are going to change cabinets.

hifiguy · « **Reply #19 on:** 25 Sep 2005, 09:41 pm »

John:

My VMPS IIa/R LEs are coming apart this fall for a sub woofer loader replacement at the top of the speakers. Order for replacement speakers shortly.

Is it possible to try to apply the black hole option when the tops are off?

Thanks -

hifi