Gravity Well Of A DarkStar

JiffyBoob · « **Reply #800 on:** 21 Jun 2006, 03:57 am »

John in CR

It came with the whole Dark Star rig. I remember Dmason mentioning he had been in there tweaking it based on some British recipe or modification, a minor one involving something to do with the power supply, that supposedly made for a happy difference. It is very transparent as far as I am concerned. It has worked out very well.

scorpion · « **Reply #801 on:** 21 Jun 2006, 01:04 pm »

WindChaser,

I have actually never heard the B200 but it gets a lot of praise whenever used. Like Dmason said the Germans kind of overwork their kits and in the case with the B200 it has meant complicated crossovers. But I am for simplicity.

What I did was just to put my left Ciare 250 baffle ("The King of Car-speakers") upside down to have it near the floor and fed it with the same monosignal as the rihgthand baffle got. I crossed over the left speaker just with a 9.2 mH choke to get 6 db slope at 100 Hz.

Then I listened. Both speakers were given the same mono signal from my NAD amp but with both the left and right channel playing. I liked what I heard. The speaker that was heard was still the right hand one and I got some 6 db bassextension as illustrated in one of my earlier posts (page 75 in the thread). This is to be expected. I can without straining the speakers get 95 dB at 50 Hz.

Now I think this proves the case. There was useful bassresponse from 40 Hz and from there upover almost 'as good as it gets'. The Ciares have a X-max of .5 mm but the efficiency is 96 dB. Resonancefrequency is 65 Hz. The Ciares have their trouble in the 2 kHz and 8 kHz region and shout
if they are not cured.

My baffles are 100 x 60 cm including wings on pianohinges of 17.5 and 12.5 cm width. They are not exceptional in any case. My livingroom is 8 m x 4.5 m and 2.3 m high and baffles are placed about 1 m from the small wall and about 1 m from corners. The measurement were taken in the listening spot about 2.5 m from each speaker.

This is the way I would like to have it. Just using two of the same drives on the same baffle and use the lower one for bassextension. If you are not satisfied with bass you get then I would go for a separate bassdipole and the main unit on another baffle physically separated.

Now I have found an European supplier that sells B200 as cheap as you get them in US so I will buy four of them and begin experimenting. There is some discussion in German fora over these units and the common meaning is that they are the best of the fullrangers that are relatively cheap. The physical construction of B200 is very good. Distortion measurements for B200 shows it to have under 0.3 % distortion for 2nd and 3rd harmonics in the interwall 80 - 16000 Hz with 80 dB SPL and under .9 % distortion with 90 dB SPL in the same frequencyrange. That's amazing.

/Erling

Wind Chaser · « **Reply #802 on:** 21 Jun 2006, 08:34 pm »

Thank you all for posting your specific arrangments with the 2nd driver. Much appreciated...

Corloc, please be sure to let us know how things work out when you try crossing over at a lower frequency. Since Richard expressed interest in trying an inductor that crosses over at a higher frequency, perhaps the two of you might want to exchange inductors so you can experiment without having to fork out more cash apart from the cost of shipping them back and forth? It would be very helpful to us all to know.

I think it's rather interesting that JiffyBoob prefers his dual B200's to a single B200 with 4 X 15" woofers. Clearly his dual B200's must be producing some very satisfying bass.

Lin, of the two arrangements that you have tried, which sounds better to you and by how much of a margin? Where did you get your 12mH inductor from and how much are they? And what are you doing with your Augies? I was thinking of making the B200 baffles 10" wide and putting the Augie on a separate small baffle to extend the bottom end beyond the capacity of the dual Visatons. That Eagle amp is perfect for bass. I use to own another creation by John Iverson, the Electro Research EK-1 strain gauge pick up system back in my analogue days. Whatever happened to John Iverson?

Scorpion, taking a second look at the data you posted seems to indicate on average an overall gain of 6 db with dual drivers. For anyone who is content or prefers to listen at moderate volumes, a driver like the B200 with it's limited Xmax should pose a problem in this application. The B200 in spite of its shortcomings is an incredible transducer. The Fostex FE 108 Sigma in Ed Schillings Horn Shoppe Horn was my first experience with a full range driver. That was IT! I was hooked. No more crossovers for me in the critical midrange SVP... Then I heard the Jordan JX-92s in a variety of enclosures, a much better driver than the Fostex IMO. But the B200 is radically more coherent and revealing by a long shot... And of course, the best enclosure is no enclosure... You won't be disappointed.

JohninCR, could you please post that information on how to avoid 1/4 resonance with Sono Tubes?

Everyone and anyone, about how close to the ground should the 2nd B200 be positioned. Would 2" be too close?

Thanks,

John.

scorpion · « **Reply #803 on:** 25 Jun 2006, 05:08 pm »

Wind Chaser,

10" would be way to small. You would run into trouble with midrange support. I would go for something like 20" to 25" as minimum measures for the main baffle to get the all over support you would like to have. But this can of course be accomplished in many different ways, as JohninCr has shown.

/Erling

opnly bafld · « **Reply #804 on:** 25 Jun 2006, 08:20 pm »

Wind Chaser,
The jury is still out on whether I like the inductors or the Rane x-o better.
I have been enjoying the sound with the inductors and I like the fact that there is less complexity.
So I have not switched back and forth to compare.
I purchased the inductors from Madisound for $21.75 ea.
My Augies are in their boxes, I have not made the cutouts in a baffle (49w x 20h) I am planning on trying.
I have also thought about making my baffles 1 1/2" thick and trying the Augies at the bottom with 1 or 2 Bs above it.
I think Mr Content at the Decware forum has the narrowest baffles I have seen/heard about at 17"+.

John Iverson disappeared in the 90s.

I have 2 Eagle amps, a 2 and a 2c.

There is a company in KC that rebuilds and "improves" (more bass, better highs, remove unnecessary parts) Eagle amps for @ $600, I am thinking about having one done.

From what others have said, 2" off the ground should work.
Mine are @ 5", because of a miscalculation when cutting.

Lin

Wind Chaser · « **Reply #805 on:** 26 Jun 2006, 08:31 pm »

This new look takes some adjustment...

The modified B200's are now on their way back to me. I also have a slightly used pair coming from Oregon but they lack 400 hours for a fair comparison. The original owner says they have less than 15 hours on them…

As per a Bob Brines recommendation, I ordered a pair of ERSE Super Q magnetic core inductors. The nice thing about these is that they cost about a 1/3 of the air cores and will work just as good in the lower frequencies.

http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=266-946

Over the past few months I've considered a number of design possibilities and now it's time to move forward with something. Borrowing from Mr Content's expertise and experience I'd like to take a stab at his current baffle with a few differences. One being to lower the height of the main driver and the overall baffle by 10cm. The other of course is to mount a second B200 starting 5cm from the bottom. In addition to that, I might add up to another 16cm width just at the bottom of the baffle.

Click on the link below and scroll about half way down and you'll get a better idea of what I'm talking about.

http://www.decware.com/cgi-bin/yabb/YaBB.cgi?board=diy;action=display;num=1143087829;start=465#465

John

Dmason · « **Reply #806 on:** 26 Jun 2006, 10:28 pm »

Sounds like a plan. Nigel has built more baffles for that thing than anyone, and your plan to distill what info is current will make for an interesting outcome sure to please. I for one would lose the point top to the baffle, I think you would be very safe in doing so.

Apparently Roger Modjeski, and his colleague have a couple of ideas for bass augmentation they would like to weigh in with, in the near future, which they believe will work very, very well, based on testing, and experimentation. So, we have Music Reference in on the act now too!!

And, coming prototype alternatives for OB drivers, to give choices, chocolate, and new Mint!!

Vinnie R. · « **Reply #807 on:** 26 Jun 2006, 10:32 pm »

Quote from: Dmason on 26 Jun 2006, 10:28 pm

And, coming prototype alternatives for OB drivers, to give choices, chocolate, and new Mint!!

I'll take the new Mint please

Dmason · « **Reply #808 on:** 26 Jun 2006, 11:18 pm »

Yes, and as if all this weren't enough, soon enough, new Mint 15 Pak, for bass pleasure. Full range mint flavor in both 8 and handy 15. So, coming soon full range open baffle sound in Spear Mint.

More to come next month. Meanwhile back in the gravity well, the B200/Signature 30 combination is something to behold. The level of driver control is really something. It widens, and deepens the image or hologram, or whatever you call that. Thing it is doing that everyone talks about.

Wind Chaser · « **Reply #809 on:** 27 Jun 2006, 12:12 am »

Quote from: Dmason on 26 Jun 2006, 10:28 pm

I for one would lose the point top to the baffle, I think you would be very safe in doing so.

That's what I was thinking. Maybe I'll put a Totem Beak on top or one of these...

http://www.shakti-innovations.com/hallograph.htm

fu_man · « **Reply #810 on:** 29 Jun 2006, 12:49 pm »

Hi
Have any of you B200 converts had experience with front loaded horn speakers? I like the idea of both of these out of the box approaches - would love to hear you impressions/ comparisons.
Fu man

ebag4 · « **Reply #811 on:** 29 Jun 2006, 02:16 pm »

Windchaser, have you used the B200 with your Augies? This is a direction I am considering and would appreciate your thoughts. It would be great if you could compare a setup with the B200/Augie vs 2 B200s.

Thanks,
Ed

Wind Chaser · « **Reply #812 on:** 29 Jun 2006, 05:18 pm »

Hi Ed,

I’m still waiting for the second pair of B200’s and the inductors to arrive. I also have yet to build baffles... so the drivers are sitting up right at a ninety degree angle on the floor. Right now as I type I'm listening to bass loaded track from Sinead O' Connor's Gospel Oak. It's really quite amazing to hear the B200 with a deep full rich bottom end. Like the Visaton, the Augie is squeaky clean in what it does, adding tremendous weight and authority.

Keep in mind I haven’t heard two B200’s on a single baffle, let alone one B200 on a baffle, but at this point I would say if it’s a case of one or the other I would go with a single B200 and the Augie. You’ll get far more extension, plus the weight and impact of a big driver.

In the end it might not be a case of one or the other, but all of them working together. I suspect a 2nd a B200 will help pick up the mid bass whereas the Augie will make it a true full range system.

Even with the drivers on the floor, I really like what I am hearing. It was damn near impossible to concentrate on writing this with the music playing in the background… This is more addictive than any of the narcotics I’ve tried.

John

ebag4 · « **Reply #813 on:** 29 Jun 2006, 05:28 pm »

Thanks John:
I think I will probably go the Augie route. My system can use a little more foundation and I believe the Augie will fit that bill nicely. Looking forward to your impressions of these various setups.

Thanks,
Ed

Wind Chaser · « **Reply #814 on:** 29 Jun 2006, 06:05 pm »

Hey Ed,

It might not be a bad idea to isolate the two drivers on separate baffles. The energy coming from Augie might interfere with the finesse of the B200 on the same baffle.

John

ebag4 · « **Reply #815 on:** 29 Jun 2006, 06:32 pm »

Thanks John, I plan to. In reading Mr.Cs comments on Decware I believe that it may be a good idea to 'Magnet Mount" the drivers and simply let them connect to the baffles via a gasket so I wont have a direct connection to the baffle from the driver. I think I have come up with a way to do this that should work well. If it works out OK I will post info here.

Ed

Russell Dawkins · « **Reply #816 on:** 29 Jun 2006, 06:50 pm »

excuse me if this has already been posted, but it was news to me.

http://www.enjoythemusic.com/magazine/equipment/0606/visation_nobox_bb_loudspeaker.htm

Wind Chaser · « **Reply #817 on:** 29 Jun 2006, 06:52 pm »

There's two threads on the Decware Forums...

http://www.decware.com/cgi-bin/yabb/YaBB.cgi?board=General;action=display;num=1141232613;start=

and

http://www.decware.com/cgi-bin/yabb/YaBB.cgi?board=diy;action=display;num=1143087829

Lot's of good information on the Fullrange Driver Forum, DIY Audio and Hawthorne Audio also.

scorpion · « **Reply #818 on:** 29 Jun 2006, 07:07 pm »

Yes, the B200 seems to be all over the place. Good Work, Dmason !

Lin, What happens if you run your OB with the two B200s on each Baffle in parallell instead of Bi-amping ? Keeping the 6 db crossover on the lower unit.
It would be interesting to hear your opinion for that setup.

/Erling

Wind Chaser · « **Reply #819 on:** 29 Jun 2006, 10:51 pm »

For the third straight day in a row, the post lady has been dropping off B200's. By this time tomorrow afternoon I should be able to post some preliminary thoughts. Ain't got no baffles, but what I'll do is just listen to a raw single driver of each and see how it goes.

John