Topic: Gravity Well Of A DarkStar (Read 174259 times)

Vinnie R. · « **Reply #380 on:** 24 Jun 2005, 12:24 PM »

Quote from: maxwalrath

I'd like to know the source and price of the acrylic stuff too. If I'm going to have a large speaker in my living room I'd rather it be clear to make the place look bigger.

All,

I purchased the clear acrylic from a local company:
http://www.plasticsunlimitedinc.com/products.html

They cut the baffles and polished the edges, but did not cut the hole
for the speaker....I had a local sign shop use a CNC machine to drill the holes. The total price I paid when all was said and done was around
$165 for each baffle. They came out perfect!

The brand of the acrylic is CYRO:
http://www.cyro.com/NewCYRO/flash.html

The baffles are heavy, so shipping might be very expensive

BTW, I'm sure we can get Louis from Omega can make some beautiful
baffles...just install the Visaton and go! I am going to be visiting him
on Monday to pick up the Lotus enclosures

Regards,

Dmason · « **Reply #381 on:** 24 Jun 2005, 01:00 PM »

Omega baffles for Visaton B200. Mmmmmmm. Now THAT, sounds good.

For those of you with larger rooms, if you prefer the look of good wood, wood baffles impart a rounder, somewhat warmer tone, the acrylic being dryer, more "literal." Both sound excellent, just different. With Louis' finishing skills, something like Ebony, with its deep figure, and the jet black B200 parked in the middle, could make a very real Art Moderne statement, in one's living room. I hope Louis is reading this thread, and has the inclination to develop some nice flavors and variations for Omega open baffles.

I envision folding baffles, with nice roundovers, recessed hinges, and a beautiful finish a la Louis, offering an almost Victorian decor element, like a drop-leaf table on its side, which can be folded up to under 10 inches wide for the static baffle.

-Richard- · « **Reply #382 on:** 24 Jun 2005, 05:04 PM »

Hi JohninCR,

Very interesting and informative...and convincing...

If you know how to mount an image in this forum...I do not...is it possible to slip in
a picture of what these look like...your description is impeccable...still...I am image
oriented to some degree and would love to see what they look like...

I also have been thinking of "fixed" wings...the piano hinges could introduce
their own "tone" to the proceedings which might be undesirable...and they
may not have the most appealing "look"...naturally there would be the benefit
of allowing the wings to be folded away...somewhat...the back of the driver
being the limiting factor here...

I think I hear the Birch plywood I used on my baffles...and as Dan has
pointed out this may actually impart some warmth and a "rounded" all over
sonic signature to the sound...which suggests that materials could be used
to "taste"...which increases the options to more precisely fit the preferences
of each listener...

When Dan first introduced the Dark Star phenomena I also envisioned problems
with the larger baffle opposing the "natural" back wave reflections...your observations
confirm this...

I am not sure I understand what you mean by a "Back Grill"...do you mean that the
grill would be mounted on a thin frame to the fixed wings in the back...the wings
being the outer edges of the grill...with the top and bottom of the grill being "open"?

Also, I would love to better understand how you applied the back bracing...could
you go a bit more into that?

Again, JohninCR, I really like your idea and deeply appreciate your sharing that
with us..

Any pictures would be a wonderful addition to your beautifully crafted descriptions.

Warm regards -Richard-

Tubo · « **Reply #383 on:** 24 Jun 2005, 08:10 PM »

Gang,

How about bent plywood or bent acrylic for open baffles? The "wings" could be bent back at 45 degrees (or some other angle)... Plywood could be finished by applying varnish, lacquer, paint, or veneer...

I am thinking of something like the bent plywood furniture from the 1950's (Charles Eames?), with rounded corners.

I don't have the skills to bend plywood or acrylic, but if we are going to ask Louis Choclos to make some OB's, then, it's not out of the question. Perhaps a group buy?

Dmason · « **Reply #384 on:** 24 Jun 2005, 09:28 PM »

Gringo In The Jungle,

First, I wouldnt mind building open baffles in Costa Rica. Maybe a garage shop around Tamarindo. Cervesas and mooosic!! Thanks for your input.

I was wondering what your thinking was with respect to the trapezoidal shape? Whether this had an overall function, or something to do with the alignment of the bass 5" drivers...looks really good. I am going to try to get around to some fixed wing baffles this weekend while I make some cuts.

The angles can be made easy if you can cut accurate angles, and the lumber yards often have pre cut biscuits and things like that that can make the going much smoother, they will usually be happy to make your cuts for a nominal charge.

JohninCR · « **Reply #385 on:** 24 Jun 2005, 10:15 PM »

Dmason,

I'll stay in the mountains where it's cooler for woodworking.

The trapezoid shape was just to come up with something interesting. I did want to make the bottom large in case I wanted to go a different route with the bass helpers at the bottom and use larger drivers. It did make everything more difficult. If I had it to do over, I'd use screws from the back since it will be hidden anyway and leave extra material on the ends of the 3 main panels and cut them at the end.

BTW, the Flinstone roof tops were necessary because I made the wings 1.5" difference in depth which was overkill.

ooheadsoo · « **Reply #386 on:** 24 Jun 2005, 10:18 PM »

Lumber yard? Is there one of these fandangled things here in LA?

-Richard- · « **Reply #387 on:** 25 Jun 2005, 01:26 AM »

Hi JohninCR,

Thanks so much for your further elucidations...nicely illustrated and
described...especially your reasons for your design decisions...

Your baffles are very original looking and look like real music makers...
nice wood also...

Do you feel the the top pieces help to direct the back wave from flowing
"upward" into the room space...or does it have more to do with an absorbent
function reducing the impact of the back wave somewhat? Also, is there a
functional reason for the top pieces to "overlap" the top and sides?
I notice you have a "bottom" piece...is that to give the wings more
integrity...or does it serve a functional sound issue....

From looking at the images of your fixed wing baffles, it seems as if the back of
the "wings" are higher then where they meet the front baffle on either side...is that
correct? And is that what you meant by "...Having the wings wider at the back helps
lessen these pressures and more importantly avoids resonances created by the
cavity shape." ?

If that is so, JohninCR, it sounds like the kind of implementation "box" speaker
designers sometimes use to displace standing waves which would accumulate
and build unwanted pressure more easily due to even sided rectangular
dimensions. I notice the rounded edges. These must be fairly heavy given that they
are solid wood and 1inch thick.

You mentioned lowering the B200 on the front baffle..what would you
think is the optimum height...below ear level at the sitting position? You also
mention shorter wings...is that to allow more of the back wave to enter into the
musical space?

I like your narrow speaker box as opposed to big box observation to explain focusing
differences due to the back wave having more "presence" in the smaller speaker...
very interesting...and proof that this whole involvement with OB's has the potential
to teach us a great deal about how speakers work...and what is really going on...

Thanks again, JohninCR, for your help and taking the time to slip these images
into your post and going into more detail about it...I for one do not find your description
"long winded" at all...I would even appreciate a more in-depth observation if you
are comfortable going more deeply into this entire subject.

Warm regards -Richard-

-Richard- · « **Reply #388 on:** 25 Jun 2005, 04:11 AM »

Thanks again, JohninCR, for sharing your thoughts and explorations with us.

A nice read and very practical considerations to ponder as we move deeper
into this fascinating subject.

When I was an adolescent, my eyes were opened to the possibilities of how good
an audio system could sound...I would take the bus to commercial business areas
where I lived to peruse the audio shops...at that time the speakers were displayed
in a kind of grid one next to the other in cutouts on a large wood wall...

You could turn a knob or flip a switch to move the recorded signal to any speaker
that interested you. No salesman stood over you or tried to intimidate you...
these stores where simple and "electronic" looking...the plush carpet came much
later...along with the "attitudes"...As a youngster I found those rooms exhilarating
and I listened very carefully to each offering they had.

They were not displayed in boxed baffles...those were sold separately...

So in one sense they were displayed as Open Baffles...although the back wave
was probably somewhat cancelled...at least for the most part...due to the large
area of the wall...I have not thought about that until tonight...this whole thing has
jogged my memory...and I feel a bit nostalgic...all a dream...our lives fade like dream
time lives...like the nightly dew that lightly smokes from the leaves in the early sun...

Warm regards -Richard-

JLM · « **Reply #389 on:** 25 Jun 2005, 12:25 PM »

So I'm pulling together the best from what has been shared here and coming up with:

Open baffle speakers (OB) offer extreme dynamics and unique imaging/room placement behaviors at the cost of loss of bass. The dipole action of a OB loads bass differently than other speaker types. Imaging is less focused, due perhaps in part to the reflection of sound off one baffle from the other speaker. The shear size of simple, flat OBs can visually/acousically dominate a room (the described garage door look in the living room).

Like any other speaker type, some drivers will work better in open baffles than others in terms of bass and midbass response. High Qts bass drivers, 0.5 or higher, are more friendly to open baffle designs. The B200 is highly efficient, organic, detailed, and has a high Qts, making it an ideal match to the Clari-T.

Digital EQ can be added to full out deep bass. One of the "dangers" of OB is leaving the simplicity of the concept in order to tweak/maximize imaging and bass response. Beyond digital EQ, adding tone controls, a tube buffer pre-amp, or subsituting a Vinnie modded Teac can alleviate concerns for lack of bass with the B200 drivers and still allow retention of the simplier/smaller OB concept.

A baffle with differently sized wings at 45 degree angles and top/bottom plates to reinforce, extend the baffle on top, add stability/mass at the bottom. The whole thing could be tapered/trapizodial in shape to vary edge distances. The wings should be narrower than the front baffle width to preserve the open baffle sound. Materials could vary (wood = warmer sound/cheaper, acrylic = drier/possibly better domestic acceptance factor). Baffle size can vary, larger ones could benefit from use of absorbent materials. The larger the baffle, the deeper the bass produced. Reinforcement of long free edges might be a good thing. Driver height off the floor nearer to ear height seems to be the best.

Seminarian · « **Reply #390 on:** 25 Jun 2005, 02:41 PM »

Also, I would assume that the concept of a sweet spot with OBs is non-existent, no?

Vinnie R. · « **Reply #391 on:** 25 Jun 2005, 04:17 PM »

Quote from: fabaudio

Quick question- What thickness should one use for acrylic baffles ?
What the heck - another question- what's wrong with using a 12" to 15" wide acrylic baffle w/o sides but strong base? Rigidity problems maybe? Of course I envision using these with a pair of subwoofers.

Hi fabaudio,

The Cyro Acrylic that I am using is 1/2". Using 3/4" was just about double the price, and the 24" x 42" x 1/2" baffle that I am using seems quite rigid. If you can afford 3/4", it is VERY SOLID!

Regarding bass, it is highly dependent on your room and baffle placement. If you are using a fast, tight subwoofer, you should be a happy camper. You need a very fast sub to keep up with the B200s!

I'm away from home now, but will be back Sunday night. My B200s are burning-in back home. I'll also be visiting Louis of Omega on Monday, and will talk to him about baffles

Oh, the possibilities!

mcgsxr · « **Reply #392 on:** 25 Jun 2005, 04:19 PM »

Seminarian - in my experience so far, the idea of sweet spot is different from my experiences with other speakers. Using box speakers, I find that the sweet spot is the only place that I hear the music from the middle of the soundstage, and moving outside of that, ruins the stereo image.

With the b200's, I find that the stereo image is riveted to the middle of the speakers, even when I move outside of one of the L or R speakers. The sweet spot, for me, in my system, blah, blah, is the realism is in the middle - if I move around, I hear great stereo over there. If I sit down, I hear the music, right here...

Dmason · « **Reply #393 on:** 25 Jun 2005, 04:28 PM »

Fabaudio

Without question you can use a 12" wide baffle. Add sides and increase baffle effectiveness. The best shots of this are the Linkwitz Phoenix.
www.linkwitzlab.com Sides would be optional, just with higher roll-off, comes higher integration/greater difficulty/ Fs of subs.

JLM

All points seem to stand, except DEQ, which will "add" more bass simply by raising lower frequency response which wouldnt be below roll off anyway. As always there is a trade off, and the more excursion for lower frequencies, the more modulation of upper frequencies. It will not bring the full range thing; Mother Nature here. DEQ I use is more to tune the room for performance of the speaker as a system, and I store some EQ curves for certain "sounds." This is why I wish to try TWO drivers on one baffle. DarkStar Heavy would still be alot easier than "Phoenix Lite."

.....Tube buffers would have to do with impedance matching between sources and amps, not driver response, and they impart very little tube-ness to the sound. No need for power such as the Teac, for the B200, which when fully broken in is highly efficient. ~97db. Teac for F2000A, ClariT for B200

The combination of the battery powered fully tweaked Vinnie amp, direct coupled to the B200 on open baffle is pretty much a statement sonic, destination audio, IMHO, heard plenty, owned plenty, built plenty, but I think the highs of the ClariT are World Class, and the B200 makes FULL USE of them, in no uncertain way.

Three years ago I went to CES, making a point of listening to as many speakers as I could -which didn't immediately turn me off, this criterion quickly narrowed the field to about five designs... Among the True Music Makers, the ONE design which stood completely apart from the fray were the Audio Artistry "Beethoven" and "Dvorak," designed by Dr Linkwitz, it turned out much later, and both -- Open Baffle. Last fall at the Denver show, of a handfull of designs that played Real Music were the Bastani's Prometheus, also open baffle. Sumpin about it. The other speakers of note were TC's horns, and Omega Super 3R/TS33. What these three designs all had in common, though their alignments were radically different, were wide range drivers, no crossovers, between 60-8000Hz. The rest of the multi way, ceramically-challenged, cupric-ally constipated designs, that just sounded plain, well, broken.

-Richard- · « **Reply #394 on:** 25 Jun 2005, 05:32 PM »

Sound staging...the effect of hearing instruments arrayed in the area
between the speakers...is very convincing with my B200 open baffles...
and nicely focused...

Last night I draped light blankets behind the baffles...since my baffles lean
back the blankets do not touch the back of the drivers...

The sound improved considerably...tighter...more focused...

it looks...well...not very aesthetical as you might imagine...but that could be
easily improved by cutting a blanket to fit the back so it does not show in the front.

Has anyone else tried this little experiment? Let us know the results if you do.

Warm regards -Richard-

Dmason · « **Reply #395 on:** 25 Jun 2005, 05:58 PM »

Richard

I did something similar; I "veneered" the back with cork. The difference was not subtle, and was highly positive. I found the cork at Aaron's Art Shop, where I picked up the acrylic paints for the baffles which were used first as canvasses for two young girls to create their Impressionist best upon, for my "Kinder-baffle" experiment in child's mural-works, cork on the back. These actually are my favorite baffles, tho' abit much for the living room. The wood and cork-damped sound is just great.

Vinnie made a good point earlier: that the roll off of the B200 specifically, was low enough to make sub' integration quite easy, as long as you made damn sure you had a tight, and blinding fast sub to go with it. Sure, dipole bass is where it's at, but I built this little box of .75ft^3 with a Dayton metal bass driver and the thing slams. I mean to say I was completely caught off guard with just how good this worked. The driver is $17 from PartsExpress, and works great in a sealed alignment, FWIW.

Next is a narrower and slightly taller baffle, with shallow wings @60' with two B200's, one low passed. Today I plan to draw something up based on Johnin's suggestions and experience. Any input would be great, I am thinking about a 54 inch baffle which is 12 wide, and about 12 inches worth of wings.

-Richard- · « **Reply #396 on:** 25 Jun 2005, 07:09 PM »

Hi Dan,

Thanks for your input Dan...as always...inspiring...I really like your open
ended Edisonesque approach...moving inexorably to where the magic lies...

I assume the cork smoothed the sound out a bit...

Intuitively I feel you are right about the 2 drivers working in concert on each
baffle...raising the sensitivity and spreading the frequency responsibilities so
that the mid range has more integrity...that way it will not be pulled into the bass
in order to flesh out the foundation of the music as it is with one driver working
the full gamut alone...giving the B200 a mate to play with...

Please let us know how that sounds...I am certain it will only create a deeper
and richer sonic field...

Are you planning on uses a digital cross over...or is there a simple mechanical
cross over that would not injure the signal and still allow each driver to operate
in there preferred frequencies?

Exciting stuff...this morning Deb put Charles Lloyd's Canto on and was astonished
at the detail that we never heard before...not just detail for its own sake mind you...
but musically important detail that allowed you to hear for the first time what Lloyd
was thinking in juxtaposing and integrating the various sounds and textures
that make up the beginning of some his pieces...a revelation!!! And in purely
musical terms...not just hifi...

The bass is fleshing out nicely now...but some constriction on highly complex
mounting orchestral crescendos like Master and Commander soundtrack...
the drivers just bog down...perhaps with more burn-in they may loosen up a bit...

Here may be precisely where your 2 driver per baffle design may offer better resolution.

Or it may be the limitation of my tube SEP amp...you mentioned the better resolution of
the digital amps dampening factor...a tricked out ClariT may be the answer here...

Warm regards -Richard-

powerbench · « **Reply #397 on:** 25 Jun 2005, 07:40 PM »

Hey other Mark,I read your earlier post and was curious if your OB wings are making any vibs??How has the sound quality,soundstage etcx changed or improved...thansk the Other,other Mark in Canada

-Richard- · « **Reply #398 on:** 25 Jun 2005, 07:46 PM »

Another quick thought I would like to share...

Music lovers who have never understood this communities profound involvement
in audio...why we spend so much time and energy experimenting and carefully
putting together a sound system...are simply not aware of the relationship between
the extraordinary resolution of realistic sound and the inner intelligence of the music
that is released within that highly resolved sonic field...

For me it about the often hidden understructure of the musical life folding itself into
the flowing surface of the sound...its innate intelligence...that creates the magic...
and a profound contact with the "mind" of music...its ability to transform us...

The B200 OB brings it all to life...Thanks again Dan!!!!

Warm regards -Richard-

-Richard- · « **Reply #399 on:** 25 Jun 2005, 08:05 PM »

Hi JohninCR,

Beautifully shaped overview of what you think is operating here...

Your thinking is clear and convincing...what I am hearing on my
B200 Baffles is not to be believed...the end of super hyped, expensive
boxed baffled drivers is imminent...the new paradigm is here right now...

And it is a grass roots movement...a gift of Dan...who obviously started
this thread knowing that a revolution was at hand...

Thanks again, JohninCr, for sharing your thoughtful, logical, incisive, pragmatic,
intuitive and fascinating insights with us...I can only hope you continue to
share your thinking with us...

Warm regards -Richard-

Author Topic: Gravity Well Of A DarkStar (Read 174259 times)