Gravity Well Of A DarkStar

powerbench · « **Reply #400 on:** 25 Jun 2005, 08:26 pm »

To the earlier OB post 'JohninCR' what are the smalllest OB dimensions we can manage with the B200 in your humble opinion???Thanks... I am in a 12x16' area.

Dmason · « **Reply #401 on:** 25 Jun 2005, 10:52 pm »

Wings on baffle = greater effective baffle width + lesser baffle diffraction = lower Fs roll off = better and easier bass integration.

I recommend trying a 12-15 inch baffle. I have two of them in my garage right now. The keyword, is try. Try for yourself in your room, because the "your room" part, is the key element. The room IS the speaker enclosure, and none of this is an exact science. That's the Edisonian part.

John

My interest in a second driver hasn't to do with bass, but >SPL, <distortion/excursion/modulation. I have two bass implementations which work well. I have five pairs of B200's, I would be crazy not to try it. Linkwitz has already implemented it right across the board, this is not uncharted territory, in the case of two drivers. Just a couple of docs playing around with speakers. One has a PhD in electronics engineering and an impressive track record with Class A components, and the other, well.....

ooheadsoo · « **Reply #402 on:** 25 Jun 2005, 11:21 pm »

Quote from: JohninCR

Test listening-
Nearfield response is just about meaningless with OB unless you will use them nearfield, so listen to and tweak your test baffles in room.

John, can you expand on this? Not quite sure what you mean by this.

Dmason · « **Reply #403 on:** 26 Jun 2005, 12:24 am »

Fabaudio

The JVC is a true music-maker. It is the living black eye to Thee High End, as far as multi channel goes. I have its predecessor. Addictive midrange, yes. When AC is clean-ish, it really shines. Try hanging five baffles from the ceiling and using it for a Holo-sonic approach to open baffles. Down-firing, multi-channel, open baffle concept.

If you're into audio addiction, that would work! And the $ you have already saved will help you justify it all

fabaudio · « **Reply #404 on:** 26 Jun 2005, 01:08 am »

Quote from: Dmason

Fabaudio

Try hanging five baffles from the ceiling and using it for a Holo-sonic approach to open baffles. Down-firing, multi-channel, open baffle concept. If you're into audio addiction, that would work! And the $ you have already saved will help you justify it all

That's exactly what I had in mind! Ever wonder why my wife and I are separated?

We're good friends though and I mentioned to her a while back that I visualized having 5 acrylic baffles hanging from the ceiling with Visatons.

My JVC serves dual purpose because I also enjoy watching high def. nature documentaries and movies with my projector and 92 " screen. Can you imagine the dynamics w/ Visatons- helicopters swirling overhead, bullets coming from every direction.............

Dmason · « **Reply #405 on:** 26 Jun 2005, 03:17 am »

Makes perfect sense; 'cept I don't know anything about car subwoofers, to judge.

John

Your direction above ~suggests something along the lines of a hybrid Hartley "Boffle," design, open back, open baffle, with the cotton stuffed behind the rear grille. This was the preferred load for the Hartley 220MSG, some consider the best wide ranger extant, and was a huge favorite exactly because of its BIG sound. It has been used on OB effectively, and had been suggested that the 220 was designed to be critically damped, though no numbers were ever made available because supposedly the behavior of the driver didn't correspond with Thiele/Small measurement. But this load was primo for the "critically damped" Hartley. A very, very good sign for the B200.

ooheadsoo · « **Reply #406 on:** 26 Jun 2005, 08:14 am »

Thanks, John. This is exactly what I was planning with regards to placing the speakers in the corner - literally in the corner with the back of the triangular baffles stuffed with fiberglass. I'm becoming more and more confident of the purchase of these drivers by the day.

JLM · « **Reply #407 on:** 26 Jun 2005, 11:53 am »

Just wanted to try to summerise the discussion after 40 pages.

So is anyone going to step up and take charge of a group buy? Several of us seem to be on the move in the next few weeks, myself included, so that would seem to leave it up to the rest of you guys. (Maybe best by someone who has ordered them before.)

The OB design I have in mind now would be 44 inches high and less than 17 inches wide (that's the size of 7/16 inch plywood I have laying around - I try to take direction from what providence puts in front of me). I'd add tapered wings make from a 2x12 with 30 degree bevels to attach to the baffle (duct tape to be used for experimentation to start with). One wing would be 4 to 10 inch wide, the other 6 to 12 inches. Add a tapered piece of 2x12 top and bottom to brace and add weight. Perhaps add horizontal braces above and below the driver mounted roughly 30 inches up. Maybe provide tilt for the top piece and the overall speaker. Add extra weight to the bottom.

BTW, I broke down and ordered up a stock Teac from Needledoctor. Should make for a good amp to break in the B200s, mess with my F200A based speakers, and to fill in for the Clari-T when I send it in for more Vinnie mods. Might even mod it down the road.

ooheadsoo · « **Reply #408 on:** 26 Jun 2005, 04:09 pm »

Quote from: JohninCR

It sounds like you are talking about a sealed box up in the corners. You'll need to run a cabinet simulation to get the correct box volume. Here's an easy one, http://www.mhsoft.nl/spk_calc.asp#sealed . For that kind of application, I think you're going to want drivers with a flat frequency response, not an uptilted one. How is this going to be used and what are your sonic goals ?

No, it will not be sealed. The triangular baffle will be not be sealed to the edges of the walls (except perhaps to the ceiling.) In fact, I haven't determined the exact shape of the baffle yet, but it won't be sealed, for sure. In the end, I suppose it might resemble an aperiodic enclosure, which operates like a sealed one, but I'm hoping to leave enough breathing room to avoid it. In other words, there is no way the triangular baffles are going to be any kind of "small."

I have in mind something like the two sides of a hyperbole right next to the axis, if that makes sense. Like the eiffel tower inverted.

mcgsxr · « **Reply #409 on:** 26 Jun 2005, 04:39 pm »

John raises a great point about the H of the driver off the floor, but I will chime in and say - remember to ensure that you can tilt the baffle back some - the best mine have sounded, is with the path of both drivers intersecting one foot ahead of me, and about 2-3 feet above my head.

I will try to make sure this is how my final baffles align.

JLM · « **Reply #410 on:** 27 Jun 2005, 10:37 am »

JohnCR,

I'm one to plan a project to death, a measure 10 times and cut once kind of guy. Einsten would have called it "thought experimentation". I built a pair of MLTL passive bass cabinets from manufacturer's plans and assembled Hafler pre/power amps 25 years ago, but have nearly zero knowledge of electronics and must borrow a table saw which limits how much experimentation I can do.

I've heard three pair of OBs:

Hurdygurdy Dave's swiss cheese specials (12 inch coaxial with helper tweeter, two 10 inch woofers, and two 12 inch woofers) that he used a separate amp to power the four woofers. The baffle was the classic 31 inch tall, 39 inch wide design on the floor and tilted back. He added 2 inch foam across the back, but had them mounted very close to the back wall due to domestic considerations. Dave is a scrounger and these speakers really makes the best use of the maximum number of pieces from his collection. Provided a big, smooth sound across the entire wall, amazingly coherent with all the complexity involved in the design.

Briefly heard a pair of E. J. Jordan 92S drivers in tombstone shaped drivers (upside down letter U) from the Chicago audio mafia at the 2003 MidWest Audio Fest. Sounded O.K., but a big room with lots of talking. (Those guys are from the like it way too loud SET camp.)

Darrel's OBs use a 15 inch pro woofer with coaxially mounted tweeter on a black vinyl /cloth covered and padded low/wide baffle (about 24 inches high and 36 inches wide) mounted on 4 inch chrome legs (very 50's look). It includes a L-pad to adjust woofer/tweeter balance. He and his wife are very talented as they work together full time restoring upscale historic homes and have had a waiting list for years. These speakers are somehow extremely flexible in terms of placement. They sound the nearly the same facing the listener, with extreme toe in (nearly facing each other), or even laying on the floor facing the ceiling. Darrel had experimented with leaving the legs off to pick up floor reinforcement, but liked the trade off with a bit more open sound. To me, the sound was not remarkable, just didn't do much for me.

Overall I preferred Dave's OBs, although they are in semi-retirement. Instead he has been using Klipsch Heresy's he picked up for $5. Recently he sold the Hersey's and replaced them with two-way EV pro monitors that use a horn loaded compression tweeter and 12 inch vented woofer in a high impact plastic case. He brought the EVs to the April 2005 Michigan Audio Fest and they were one of the more pleasant sounding speakers there.

ebag4 · « **Reply #411 on:** 27 Jun 2005, 05:21 pm »

Gents:
I spoke with Solen today. They tell me that a 20 piece order could take a 10% price break. They stated that 10% was it for an individual . They went on to say that if a company were to purchase them an additional 10% could be given for a total of 20%.

Wolfgang @ Spectrum Audio said he could give us better pricing if he had more information.

For a single pair Spectrum was about $25. more for a pair shipping to the US.

Ed

Dmason · « **Reply #412 on:** 27 Jun 2005, 06:14 pm »

Although I should not be counted as part of a group buy, I have ordered from both Solen and Wolfgang in the past. Wolfgang somehow gets product from Hanover to being handed over, in about a week, or just under, and turns around emails fast.

Solen are order takers, and once in asking about a resistor value for a shunt, I realized this guy didn't have a clue. It seems despite the increasing interest in the Visaton stuff, they aren't inclined to stock. The wait can be considerable, as in up to 6 weeks, and if they slip and pack an invoice, then you get Customs.

I for one, am not into waiting a month and a half for my new toys, but to each his own. With Spectrum, you get Wolfgang, who is endlessly interested in this stuff, and is single-handedly responsible for turning the world on to the wonders of the Ciares and B200's on open baffle. The guy is talented as well, and is the only one who ever came up with a working MLTL for the B200. I consider him an asset in the truest sense. My vote goes to Wolfgang, who is a very organized one man band with a sharp pencil: he knows there's ALWAYS more..

I have no biases, only my experience here, but there seems to be some inherent benefit in buying a German technical product from a knowledgeable German.

Bemopti123 · « **Reply #413 on:** 27 Jun 2005, 06:24 pm »

Hi Dmason:

There is no doubt about the efficiency of Wolfgang, especially after you narrated your experience, but do you know the price of the B200 from him? I read on a price list somewhere, that the B200 are priced at 150 Euros, which is about 30%+ which the really bad rates we have against the dollar. I wonder if he can do that 20% deal for a group buy and especially with a favorate USB based price.

When you ordered them from Germany, did you have to pay customs or even tariff?

mcgsxr · « **Reply #414 on:** 27 Jun 2005, 06:26 pm »

Being in sales, I would always buy from the responsive person, who knows their stuff.

I am set for b200's, but I just share that comment, from my 15+ years working with people selling stuff to them to solve problems...

Dmason · « **Reply #415 on:** 27 Jun 2005, 06:33 pm »

Only tariffs if they are asleep enough to include an invoice. So I got a headache from Montreal, but nothing more than an incredibly well engineered packing job from Hanover.

I think the EU price was more like $125USD, or something, can't remember. As I am set with five pairs, I leave those calc's to someone else. Best to get number of actual buyers, before asking anyone to sharpen their pencil, when they wouldn't know how much packing to remove from the deal in the first place

Mark's opinion is the succinct version of my own. I prefer the relationship with an actual practitioner, to the kid on the phone. Wolfgang is as totally converted to OB as I am... FWIW, Wolfgang was far more fluent in English.

ebag4 · « **Reply #416 on:** 27 Jun 2005, 06:54 pm »

Guys:
I wasn't certain if it was OK to post prices, but since some are, here you go. These are prices quoted for a single pair of B200s shipped to Lanesville IN (no discounts shown), they are:

Solen $325.24 USD
Spectrum $292. Euro or about $355.01 USD

Wolfgang also went into greater detail about the shipping cost (2 driver ship for same price as 3 @ 42. Euros, 7 drivers ship for 62 Euros) and stated that he could dig into other shipping methods and pricing for us today if we asked.

tyee · « **Reply #417 on:** 27 Jun 2005, 07:02 pm »

Solen just called and said their order of B200's came in and they're shipping out tomorrow.
I ordered from Wolfgang last week at 302 Euro.

-Richard- · « **Reply #418 on:** 27 Jun 2005, 08:22 pm »

I need a link to Wolgang's website...or a phone number...

I would like another pair of B200's as well so I can experiment without
having to give up my daily dose of musical nirvana...ahhhh...the open
baffle sound is...SEDUCTIVE!!!

Thanks for your help -Richard-

ebag4 · « **Reply #419 on:** 27 Jun 2005, 08:37 pm »

Here you go Richard:
website (in German) http://www.spectrumaudio.de
email spectrumaudio@t-online.de

Ed