[jrebman]

Assuming an 8 ohm load ,voltage divided resistance equals amperage.
The driver saw 15amps of current which when multiplied by the voltage equals 1800watts at 60 Hz. Speaker fuse anyone?
Scotty

Close enough -- but you've got a reactive load, so power factor has to be figured in as well.

Haven't seen a fused speaker since the 80s myself, and would never put a peak current limiter in any speaker I own or make.

-- Jim

[Wind Chaser]

I'd be really interested to hear what you and others think about phase plugging the B200s.  I'm assuming you're using the plugs available from Planet 10?


I would love to try the OB thing, but there is just not room enough in this house to get anything more than 2 feet out from a wall, and I just don't think that would cut it for an OB.

Jim

Planet 10 provided the phase plugs for my B200's.  Buried somewhere in this thread is a report I did on what I perceived to be the differences they make on the B200.  Auditory discernment is a peculiar thing.  Without going into detail I'll just say some people have more than others, hence they are able to perceive and recognize differences that elude others.  Based on my experience I can whole heartedly recommend the modification.

The modification isn’t that difficult to do.  There’s a clear step by step illustration of how to remove the dust cap on Dave’s (Planet 10) website.  With no prior experience I performed it myself on a replacement driver.  All you need is a steady hand and a little patience.

As for the open baffle approach, once you experience it with a good dynamic driver, I seriously doubt you’ll be able to find much pleasure in listening to conventional speakers.  Only an open baffle can do what an open baffle does best; that is bring a presence to the music making it all the more believable.

Since I divorced myself from audio, I don’t hang out here too much.  I’ve moved on with new priorities but occasionally I like to check in and see what’s up.  Kind of like staying friendly with the ex wife if you know what I mean.

John

[Wind Chaser]

I am in total agreement with Dmason, the B200 (like many quality drivers) can handle far more power then what it is rated for.  I’ll qualify that by saying long as the power is clean and the amplifier is competent. 

Pushing an amplifier to the point of clipping doesn’t do your speakers or your ears any favors.  Stay within the range of the amplifier and the risk is negligible. 

A clean amplifier that doesn’t hold a tight grip the driver is an incompetent amplifier.  I’ve seen this happen before with a highly regarded tube amp that costs big bucks.  When low frequencies at a very moderate volume cause a driver to react like it has Parkinson’s disease, that amp, no matter how clean and musical is threatening the life of the driver.

Ed Schilling once told me he drove in excess of 10X the recommended power into a pair of speakers rated 40 watts max.  In his enthusiasm he kept pushing them harder and harder until they finally failed.  I bet if the amplifier had not ran out of power, the drivers would have suffered no harm.  However Ed is the kind of guy that could clip the world’s most powerful amplifier - whatever that might be.  Hillbillies, you know?

John

[opnly bafld]

I agree with Dmason and WindChaser on the power thing, the B200s don't mind a little extra at all.

DarkStar the thread that refuses to die.
It would be very cool if it can hit 100,000 views.

Lin

[JohninCR]

Now I remember why I stopped posting in this thread, however, I feel compelled to do so one more time because there are still those coming in fresh to the thread who might be mislead.  The question here is not whether the B200 can handle more than its rated power capacity.  It's a well built, well engineered driver, so I have no doubt it's voice coil can thermally handle more than its rated power of 40W or even its rated max power of 70W.  The question is why would someone want to.  In an open alignment it only takes a handfull of watts to drive it to full excursion playing music with reasonable bass content, say in the 50hz range, and a handful of watts is painfully loud through much of the frequency range with the B200 because it is an efficient driver.  Obviously with some types of music containing limited bass content, much more power can be applied.  Had Windchaser's AC current been at 600hz instead of 60hz, the B200 may have even survived the ordeal if it was of short duration.

With a Qts of .75 the damping factor of an amp isn't much of an issue, since the driver itself is nicely dampened.  That's more of an issue with very high Q drivers where the driver is unable to control itself very well, and small bass impulses start the cone moving and the amplifier's damping factor kicks in to help stop the cone from travelling farther than it is supposed.  In either case once you send a strong enough signal to the driver it will still go into over-excursion regardless of what amp is used.  It's quite obvious when a driver needs an amp with a higher damping factor, because bass notes sound like the cone is flopping around without control.  I've never heard that with the B200 and I have amps with a minimal damping factor and others with a high damping factor.

Any comparisons with Ed's high power experiment are simply invalid.  Ed's driver was in his well designed horn, for which control over cone movement is inherent in the same design.  I use the same driver in an open alignment, and more than just a few watts risks driver damage, compared to the 200+ watts that it took to meltdown the driver in his horn.

The B200 is a fine driver with great smooth tonal quality and a high level of detail.  It is well built and designed for OB use.  I feel it's important to rehash a few things:

1.  The B200 has a rising response, which is a matter of sonic and musical taste, along with individual audio sensitivity in the range where our hearing is most sensitive, 1khz-5khz.  Most who object to the rising response find a simple filter that flattens response at a slight cost of overall sensitivity to be a good solution.  The nice thing is that although the response rises, it is a gentle and smooth rising response free from objectionable spikes unlike many other full range drivers, especially those with whizzer cones.

2.  Almost everyone who is initially satisfied with the B200 alone on OB searches for a solution to increase bass response, because even with a big baffle the bass is lacking.  At first many are surprised by the amount of bass you do get, because the roll-off is so gradual and extended compared to many speakers that roll off steeply below 80-100hz.  So the fundamental tones are there, just reduced in level.  Just look at Visaton's own graph of the B200's infinite baffle response. http://www.visaton.com/en/chassis_zubehoer/breitband/b200_6.html .  Then factor in additional bass roll-off due to dipole cancellation,  and what you see is what you get.  We all fall in love with the seductive OB mids with the B200, then just add a little bass fill to be a happy camper in the long run. 

3.  Many find that the top end, which starts rolling off at about 10khz, especially when listening slightly off axis, is insufficient, but that is easily cured with a supertweeter to fill in the missing "air" at the top.  Even though you end up with a multi-way speaker, the main driver is covering such a wide range compared to typical multi-way speakers, that you can still retain the coherence of a single driver speaker.

[opnly bafld]

Now I remember why I stopped posting in this thread, however, I feel compelled to do so one more time because there are still those coming in fresh to the thread who might be mislead.

I am soooooo glad you felt you had to post here one more time.
You should change your tagline from OB fanatic to OB Savior.

with biting sarcasm,
Lin

[dewar]

Seeing as you mentioned supertweeters... I've been thinking along these lines, not because I've felt the B200's lacking but simply because I like chasing perfection in my free time.

Could anyone suggest an affordable supertweeter that might do the job? Are phase problems an issue?

I'm also looking at trying out a DEQ2496 to pull down the 1-10k rise. This would raise the last octave relatively speaking, but should I want more 'air' is it feasible to boost the last octave digitally? It wouldnt use up headroom like boosting the lowest octave would it?

I hope I dont sound like I know more than I do, I'm the neophyte here. So any help is greatly appreciated.

cheers

Bevan

p.s  I just tried out a $100 'Tubalizer' tube buffer between my custom Clari-T and B200's, hoping for a bit more body/warmth. Noticeable distortion though so it goes back to Italy. Wondering if it may have been a defective unit as I have heard only good (though few) things about this little gadget.

[Wind Chaser]

Now I remember why I stopped posting in this thread, however, I feel compelled to do so one more time because there are still those coming in fresh to the thread who might be mislead.

I am soooooo glad you felt you had to post here one more time.
You should change your tagline from OB fanatic to OB Savior.

with biting sarcasm,

JohninCR’s impromptu encore is reminiscent of an old proverb...  As a dog returns to his vomit, so a fool repeats his folly.

Anyone who has reads this thread can see his three points were carved up and debunked many pages back.  It should also be pointed out that JohninCR previously flushed approximately 50 of his posts from this thread.  Now he’s back regurgitating the same things. 

Ignore and move on.


Note:  Anyone with dead horses, please ship to Costa Rica

[Wind Chaser]

Bevan,

What do you have up front for a source?

John

[JohninCR]

Since science, logic, common sense, and courtesy are no longer welcome in this thread, I'll make this my last post.

BTW, just because people advocate using extension cords to make speaker wires doesn't mean you're supposed to plug the other end into an electrical socket.

[konut]

BTW, just because people advocate using extension cords to make speaker wires doesn't mean you're supposed to plug the other end into an electrical socket.

Awhile back I read somewhere, I think it was in Microsoft news groups rec.audio.pro, that at JBL, years ago, they used to wire up a bunch of woofers in series/parallel and plug them into the wall outlet to break them in overnight.

[Russell Dawkins]

JohninCR’s impromptu encore is reminiscent of an old proverb...  As a dog returns to his vomit, so a fool repeats his folly.

nice 

[mcgsxr]

I doubt this crap is why this thread has almost 100,000 views.

Can we please get on with the OB fun?

[corloc]

I'll second that!!

[-Richard-]

It may be helpful to new comers to this thread to mention again that this threads successful "run"
is due to several important factors each of which is worth noting:

First the OB experience using the Visaton B200's and a simple baffle is inexpensive and rather
easy for the inexperienced DIY audio enthusiast... like myself for example.

Then there is the experience of learning to listen with an entirely new appreciation of what is
possible in home audio... the OB dipole effect is quite fascinating... once one gets accustomed
to the "out-of-box" fully saturated sound of OB's it is remarkable how you can begin to hear
the effect of the interior of boxes... no matter how well designed and implemented they are.


Also, the knowledge one gains from the direct experience of adjusting to the OB sound will
help you to establish an entirely new set of values in audio equipment... including amps,
CD players and so on.

DMason's original impetus behind this thread was to help all of us to get off the audio
mafia/magazine/authority addiction... to realize for ourselves what he discovered after going
through countless speakers in his systematic search for where the magic resided in audio
equipment.

What I have learned since discovering the excitement of OB speakers is incalculable and priceless.

I am deeply grateful to DMason for starting this thread and for affectionately nudging me to
get into the OB experience. In solving the minor anomalies that are part of getting ones OB's
to sound fantastic is part of the learning experience that is so valuable.

Whatever I do in audio in the future will be informed by this fascinating exploration.
Try it yourself and discover what the excitement is all about.

Warm Regards ~ Richard

[dewar]

Wind Chaser,

I have a Denon universal playing into a custom Clarit-T, and a Monica2 on the way that I would use downstream of prospective DEQ.

Thanks for any input,

Bevan

[Wind Chaser]

I am deeply grateful to DMason for starting this thread and for affectionately nudging me to
get into the OB experience. In solving the minor anomalies that are part of getting ones OB's
to sound fantastic is part of the learning experience that is so valuable.

Whatever I do in audio in the future will be informed by this fascinating exploration.
Try it yourself and discover what the excitement is all about.

On that note it's worth pointing out a few things...

One being that this thread has inspired a lot folks to dabble with open baffles, a concept they most likely never considered, or perhaps never even heard of before.

Because of the immense popularity of thread, a whole new Circle has been spawned dedicated exclusively to open baffles.  If it hadn’t been for this thread, that sandbox never would have opened.

It’s great to have people from all over the globe participating in this experiment, sharing their insights, and even more importantly sharing the results of what they discovered along the way.  Obviously what works for one person will not necessarily work for another.  We are all dealing with a different set of constraints and preferences.  Failure to recognize this has historically proven to be problematic for certain authoritative personalities who tend to overstep the boundaries of playing nice…

The Gravity Well of a DarkStar has proven to be quite contagious.  Hopefully it will continue and attract more open minded, non-bigoted people with a passion for musical excellence who are willing to try something different.

Don’t be afraid to let your talent shine – ani difranco

[Wind Chaser]

Bevan,

Your amp and speakers are very telling of what’s upstream.  It is my opinion that you’ll gain a whole lot more with a better source than by adding super tweeters.  I share your opinion that the B200’s do not sound as though they are lacking up top.  The B200 can convey the tone and texture of cymbals very accurately.  Bear in mind that with multiple drivers, you give up the point source.

I have no experience with the DEQ2496 so I can’t comment on that but I believe there are others here who may have…

A good quality tube buffer between your source and your amp will warm things up.  Check out the ZBOX by Decware www.decware.com/newsite/mainmenu.htm  It is a lot more money than the Tubalizer, but it’s made by a true audio purist in the good old USA.  If you are lucky, you might find a deal on a used one.  It isn’t dead quiet, but everyone who has tried it says it’s the real McCoy.  We certainly can’t say that about the Tubalizer.

The Monica 2 may just well be the ticket.  The output doesn’t have the most gain but that shouldn’t be a problem as the input sensitivity on the Clari–T is higher than average.

In any case you are definitely off and running.

John

[dewar]

Thanks for that Wind Chaser.

The Zbox looked the ticket, but was disappointed to see it only comes in 110v.(I'm in Oz)

The supertweeter is seeming less appealing now. I think a bump on a DEQ might be worth trying still. When I measured the speakers on the weekend they seemed to be pretty flat though 12db down from 10 to 16K. Doubt I can hear much above that.

2 other questions came to me today.

Playing white noise through left then right speaker I noticed a very slight tonal difference between my two drivers. I'm wondering how common this is? I plan to get two more drivers in the future to run a 4.1 system so I'll see if I can find a better match then.

Another question, do any of you guys have any theory on whether it is better to put the larger of ones two wings on the inside or the outside?

Many thanks

Bevan

you and Ani Difranco fan? me big time!

[dewar]

Just had to post, I'm at the moment listening to the late Chris Whitley's Dirt Floor. I swear if I was a Dark Star salesman this is what I would have playing on repeat. Vocals, steel guitar and footstomp recorded in his fathers tool shed, direct to 2-track analog via single stereo ribbon microphone. I almost feel I'm being rude typing while he's singing...gota go.