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The Purple speaker: an $18, 8" fullrange!

I'm excited to introduce a brand new, one time offering from Wild Burro Audio, The Purple Speaker. These are brand new speakers from my normal US factory, made to the same standards as the Betsy and BetsyK. They have a paper cone, foam surround, steel basket and a 10oz magnet. The Qts is high enough to work on an OB, but due to the different suspension, the compliance is low enough that boxes can be reasonably sized! These specs are about as close as you can get to an all-around fullranger.

In addition, I thought I'd add another interesting wrinkle. As they are, no whizzer or dustcap is installed. I have noticed that folks often like to mess with the whizzer and/or bottom of the cone, be it the 99 cent tweak or the fancy stuff that Rethm does to Lowthers. So, with each speaker you get three different whizzers! The smallest is the same one used on the Betsy. The other two might look familiar to followers of other US made fullrangers. It only takes a minute to glue them on, but having them uninstalled makes it very easy to modify them prior to installation. The large whizzer begs to be cut to a more interesting profile. Think of the possibilities for ENaBLing! Of course, you can also cut one down to make only a dustcap and have a widebander.

Of course, the best news is the price! I got 'em cheap, so you do too. The intro price is $18 each, $36 for a pair. I've already spent quite a few hours listening to them in my open baffle test mules, and I think you'll be as pleased as I am!

I've got one batch of these, and I'm hoping to keep quite a few pairs for myself. So, don't delay! Give me a holler and I'll get a pair on your doorstep ASAP.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 

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The curve shows the speaker as it comes: no whizzer installed. The other pic is the smallest whizzer, the one that is standard on the Betsy/BetsyK. Obviously, this is the one I'm listening to now!

As they are hard to read, here are the T/S specs in print:

Re 6.6 Ohm, Fs 68.5 Hz, Sd 211.2, Md 10.5g
Bl 5.08, Qms, 4.80, Qes .770, Qts .664, Spl 95db
Vas 48.744L, Mms 7.02g

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 
I am terrible about forgetting attachments. jrenkin, I'll get back to your PM later. I just wanted to correct the omission quickly! I am pretty sure I have some planet10 phase plugs that will fit. If I do, I'd be happy to toss in a pair for you.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 

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Much interest here! I'll get back to some emails soon, but here is the gist. $13 should cover FedEx to the US. So, for all you US folks, the total is $49 for one pair shipped. You can paypal me at: paul at wild burro audio dot com. I am still waiting for the giant whizzers that appear in the middle of the first bunch of pics. I have the one from the first pic, as well as the one pictured in the baffle. So, if you don't want the big one, I can ship now. Otherwise, it might be a week. Either way, a paypal in my "orders" folder makes you very easy to keep track of!

I'll start getting back to PM's and emails.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 
I'll get back to those with shipping questions as soon as I can. I've been really busy. On a related note, between being busy and only having had these in my possession for a couple of days, I have yet to compare the whizzers! I think you could actually cut one off and glue another one on. It might be tricky, and you'd of course want to avoid getting junk in the gap, but I bet a careful hand could do it. What I'd really love to do is develop an interesting edge, but I'm not sure when I'll have the time.

BTW, from the looks of the graph, those that like hot high frequencies ("detail" and "speed") will like the big whizzer. It won't go quite as high as the smaller ones, but it has plenty of output at 10K! Hopefully they arrive soon.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 
I have been mulling a OB dipole experiment, I think this could possibly work wonderfully. The graph shows excellent low frequency response, but an Fs of only 68. Is the graph based on a particular baffle. How many pairs do you have?

Don't pay any attention to the low frequency performance in basic driver response graphs! (For the record, this is a standard test baffle at the factory). People email me and say, "I was thinking of getting the BetsyK, but the Betsy appears to have much better bass on the graphs". Drives me nuts! Plug the numbers into a simulation. Download a spreadsheet to simulate open baffles. It won't be perfect, but it'll give you an idea. Don't forget to think about your amplifier's output impedance. There is a reason JE could get away with some lower Qts drivers than one would assume work on an OB. . .

(On a related note, don't judge the bass of a driver meant for a box if that driver isn't in a box!)

FWIW, another pet peeve is folks focusing on the Fs. For some reason, low Fs sells speakers. I'd consider using a stiffer suspension in the Betsy/BetsyK so the boxes could be smaller, but I'm afraid nobody would buy them as the Fs would be higher. Simulate this speaker and the BetsyK in a 2 cu ft (reasonably sized) sealed box. What does that low Fs get you?

Finally, as I am also prone to repeating, single 8" fullrangers in an open baffle are no recipe for big bass. Build a large baffle and you can get into the 60's. Listen near field, and don't pump a bunch of watts through them unless you are running some sort of high pass. I think single driver OB's are wonderful, and what they do well is hard to duplicate any other way. But they certainly aren't the ideal speaker for rocking out in a big room.

sorry (sort of) to rant,

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 
Paul,
Speaking of Wild Burro! JK. Thank you for the info and insight. I was actually considering using this as a mid range paired with two woofers and a Neo3PDR or standard Neo3. Was looking at your Betsy model, but this is hard to pass up for the price. Not sure what to do about the cone as I am a newb. Considering driving the whole thing with transconductance amps. How about that for wild!
 
Given the bucks you are dropping on the project, you might want to consider the Betsy or BetsyK (depending on how much efficiency you need and where you plan to crossover to the woofers, the BetsyK being more efficient, the Betsy being easier to cross over lower). I want to avoid making comparisons (all of my speakers are good!), but the Betsy/BetsyK are worth the extra few bucks in a project you are spending a great deal of time and money on. (As you are a newb, I feel compelled to point out that projects always take longer than you think! For example, what started today as a quick little project for my wife turned into hours of shopping and plenty of work for tomorrow.)

By "what to do about the cone", are you referring to the whizzer? If you are using tweeters, I'd either use a phase plug (make your own or Planet10 can supply the right size, same as the Betsy/BetsyK), or you can cut the whizzers into dustcaps. If you goof up one pair, you've got more to mess with.

You may have done plenty of modeling and have something specific in mind. But unless you are looking for a narrow baffle, dollar for dollar, big woofers often look better to me than multiple little ones. I'm speaking mainly of OB, but I'm sure some of the same applies to boxes. I'm a big fan of the Jensen/Foster 15"'s from Jack Hidley. Plenty of excursion for such high efficiency, great build quality, $60! They could be fun in big boxes too. If you want an OB with no shelving, then the Alpha 15 or Goldwood 18 appear to be the way to go.

Finally, if you are looking for an extended learning experience, you could do the whole project progressively. Start with a fullranger. Then add help at one end, then the other. It would, of course, require patience, but I bet you could learn a great deal.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 
Finally, if you are looking for an extended learning experience, you could do the whole project progressively. Start with a fullranger. Then add help at one end, then the other. It would, of course, require patience, but I bet you could learn a great deal.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers

Its funny you mention this as it was my most likely route. Not that you are biased, but how does the betsy stack up against the Alpair 12?:D
 
Interested in knowing what the X max. and power handling of the driver is, if it is close to the Betsy I might be interested. Not so thrilled with the steel basket not having enough opening for the back wave to pass through there might be to much bounce back thru the cone under high power application. Certainly like the idea of not having the whizzer and dustcap installed, at one point I was going to inquire whether it was possible to get the Betsyk without the wizzer and dustcap.
 
The Purple Speaker is not a Betsy at a lower price. The Betsy and BetsyK are flat-out better. Granted, I haven't spent tons of time with the Purple, and there are probably ways one can minimize the differences. But Betsy is darn cheap in her own right, so those looking for the highest performance best go with her!

Power handling should be very similar. But, the Purple Speaker does have a lower Xmax at around 1.5mm. Notice that this is still more than some others give you! In addition, it has plenty of Xmech, and with the stiffer suspension, should be plenty physically tough.

As far as the basket goes, if you want to trade any of the speakers in the pic for the Purple and its considerably more open basket, let me know. I'll even pay shipping!

Seriously, I understand that more open baskets are ideal. But I also suspect it is something that will net you that last few percent of performance, often at a high price. But look at the Fostex 206. Or some of the smaller diameter Lowthers. Or especially the Altec! I don't think the basket will make or break you. The idea with Wild Burro Audio in general is to exploit the law of diminishing returns. For those that want the ultimate, they best be prepared to go elsewhere and pay a much higher price!

And, my experiments tend to show that the design of the speaker system matters quite a bit more than small details on the driver. It makes some folks happy to spend tons of money on really nice drivers, but often they'd get better performance from a competently designed system built around more modest constituent parts. Just my opinion,

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 

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