Wild Burro Audio Labs

New Cone

Paul Janda — Sun, 12 Feb 2012 16:15:41 +0000

If you’ve seen the new Field Coil prototype, you know that Wild Burro has a new cone. The short story is that it’s a simple paper that sounds much like the old cone, but with a bit more high frequency extension, and its black instead of green. However, I’d like to take the opportunity to share a bit about the history of the old cone and some of my thoughts on fullrange speakers, with a couple of comments about audio in general.

I think enough time has passed that I can let the cat out of the bag. The “old” cone was previously marketed as a “Hemp Matrix”, made of Hemp, Carbon Fiber and Kevlar. I won’t go into detail about how I ended up with it, but its worth pointing out that a year or two before I started Wild Burro, the same cone might have set you back 2-4 times as much per speaker, and was well received at that! The tooling to build those cones no longer exists, so I, nor anyone else, will be selling them in the future.

I don’t care, because my new paper cone sounds just as good. Honestly, most paper cones designed for fullrangers seem to work pretty well. I once had some graphs comparing the Hemp cone to a very popular, similarly priced product, measured on the same rig on the same day. They differences in frequency response were awfully small despite the cones being very different! If we compare my new cone with the old, the differences are tiny. A degree of difference on the mic angle makes a greater difference. Sure, different cones have narrow peaks and dips in different places, but I think other things matter far more. Honestly, naming the type of fiber in the paper matters only in marketing.

To my ear, the implementation of a loudspeaker driver makes by far the biggest difference in sound. You need a box and amp that match the speaker. Sure, one tune will sound better on a speaker that has a peak at 6K and another will sound better with a peak at 6.1K. But the overall shape of the response as dictated by the enclosure and the electrical characteristics (impedance curve!) of the speaker will make a huge difference on all material. If you like the “detail” and “speed” of a low Qts speaker with a shorting ring in a vented box, what you like is the lack of bass and hot top end. Similarly, if you listen to a big fat dome tweeter off-axis, you probably like it because it rolls off hard in-room above 8 or 10K. That is nothing to be ashamed of. If you like what fullrangers do, you’ll probably like many of the fullrangers on the market. Choose one that allows you to build the sort of system you want. Think about efficiency and box type. Be honest with yourself. If you want a very bright speaker, or a very small speaker, other people’s products will suit you better.

So, the new cone is slightly different, and if I had to, I’d say it’s a bit better because it has a little more extension. And while it is sad that I don’t have any fancy words to market it with, at least I can be open about what it is: a traditional paper cone. As always with my products, it represents an enormous value. And whether or not it works for you will depend on whether you like the peculiarities of fullrangers and how you implement the speaker. Of course, if you want them to be green colored, you are now out of luck. The best fullrangers I think I’ve heard, the field coil prototypes, use this cone. You can’t buy them. At least not yet.

If you are looking for fairly flat in-room response from one speaker in a simple enclosure that works with a low-powered amp, whether green cone or black, you’ll be hard pressed to do better than the Betsy or BetsyK.

Paul

Sale: 25% off BetsyK! $41.25 each!

Paul Janda — Mon, 28 Feb 2011 19:33:29 +0000

Some seasons the BetsyK is more popular, sometimes its the Betsy. Lately it seems as if everybody is building OBs, so I have too many BetsyKs in stock. Bad for me, good for you! The BetsyK is my speaker of choice for enclosures of any sort. But, it can also be pressed into use on an OB. They are, of course, easy to use with helper woofers. But, they might be the best choice on their own for amps with a high output impedance (that raises the total Q of the system). So, some SET owners and many folks with classic/vintage pentode amps might find the BetsyK to be the ticket. Even if you are running new solid state, you can always add some series resistance to adjust the Q to taste. And if you are interested in building a box, poke around my forum at DIY audio for some great options from simple and reasonable to giant and fun.

I can’t offer too many pairs at this price, this is just a temporary stock correction. Let me know soon if you are interested, as this deal will go the way of the Purple before you know it!

Paul
Wild Burro Audio Labs – DIY Full Range Speakers

OB’s with woofers!

Paul Janda — Thu, 03 Feb 2011 15:58:22 +0000

My system info is badly outdates, so I figured I’d start where it counts: with the speakers! The BIBs stayed in Minnesota when we came west. The basic open baffles were serving me well, but the best thing about WBAL is how inexpensive it is to try something new! OBs with helper woofers have been very popular lately, so I figured I’d give it a shot myself. As usual, I choose to go my own way with a tapered U-baffle and a pair of surplus woofers from Jack Hidley. I’m using a minidsp to EQ the woofers. I had to build a new amp with a pre stage so that I could drive the digital signal processor and the passive line level crossover on the Betsys. You can read about the full implementation here: http://www.minidsp.com/support/forum/6-diy-hifi-projects/115-minidsp–wbal-betsy–15q-woofers–dipole-fun The end result sounds great! Let me know if you are interested in doing something similar.

-Paul

An $18 Fullrange: the Purple Speaker!

Paul Janda — Fri, 03 Dec 2010 15:50:06 +0000

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

Zillaaudio’s Betsy & Boomer Kit

Paul Janda — Mon, 16 Mar 2009 18:00:26 +0000

Jeff at Zillaaudio (Godzilla on the forums) has put together a fantastic looking OB kit for the Betsy. It includes a pair of 15″ woofers, an outboard amplifier for them that includes a crossover and level control and all the cables you need for <$300. You can order direct from his site. This is really a great application for the Betsy, and could take her to a whole new level. The price to performance ratio is perfectly in line with WBAL principles, and this sort of DIY’er cottage industry networking is really exciting to me. Check out Jeff’s site for more info: http://www.zillaaudio.com/betsy-boomer.htm I’m going to get this up on the projects page as soon as I can.

Dimensions

Paul Janda — Sat, 07 Mar 2009 20:10:07 +0000

I’ve been fielding a few questions about the actual dimensions. I’ll try and get a good graphic from my OEM, but for now: I use a 7 3/8″ hole. It could be a little smaller, but this gives you some room for error. The OD is 8.25″ and the fastener centers are 7 7/8″ across. For those of you flush mounting, the basket/gasket edge is 5/16″ (don’t forget room for your gasket!). BTW, my BIB’s have bolts just a little under 8 3/8″ across. I put a little dent in the outside of the basket for each bolt, and secure my BetsyK’s from outside the frame under the edge of button head cap screws. I works really slick, because I can swap drivers (well, those I’ve dented) by removing only two screws and loosening the bottom two. pj

20% Discount on a Second Pair!

Paul Janda — Sat, 07 Mar 2009 04:58:00 +0000

I didn’t know if anybody would be interested in two pairs, but I’ve already had an inquiry. So, how about this: Buy one pair get a second pair (ordered at the same time) at a 20% discount. That’ll save ya’ $15 on a pair of Betsy’s or $16 on a pair of BetsyK’s. If you want a pair of each, I’ll still take $16 off. BTW, last I checked, over 160 folks have visited the site. So, I had poured myself a celebratory beer, an Ommegang Abbey Ale. I left it on a table next to the couch. While I was typing, I heard a funny noise. I looked over to where I had left the beer, and our Pico, our 9.5 lb toy poodle was guzzling it as fast as he could. It’s 8.5% Alc. He’ll sleep well tonight. And yes, I’m still going to drink the beer.pj

Why a single driver open baffle?

Paul Janda — Sat, 07 Mar 2009 04:44:41 +0000

Luminary designer Seigfried Linkwitz has been a proponent of multi-way open baffles for many years. Recently, commercial manufacturers like Jamo, AV123 and others have introduced highly successful models. And of course, the panel speaker (electrostat and planar) folks have been there all along. Getting the midrange driver out of the box brings an intoxicating openness and clarity to the sound. The speaker sound big and unencumbered. Voices and instruments sound “there”. Of course, there are downsides. Dipoles need to be positioned out in the room a good distance, as they’ve got sound coming from the rear of the speaker. If you want to fill a big room with deep, chest thumping OB bass, you’ll need 4 woofers. Or a woofer in-a-box on each side.For most folks and most music, the midrange and coherence of single driver OB’s is worth losing a little bass impact. You can leave your OB’s in the corners for background music and TV (something absorptive behind them wouldn’t hurt). When you’re ready for some serious listening, drag them out to the middle of the room. Listen near-field. As you don’t have to worry about driver integration, you can get as close as you want. If you’re like me, you’ll get lost in the midrange. And you’ll hear all of the bass line. It will be perfectly integrated with the music, neither disconnected nor overwhelming.There are practical considerations for the DIY’er too. Betsys work with amplifiers from 1/2 to 300 watts. You don’t need to be able to cut accurately. The bass is neighbor and wife friendly. The rear wave is out of phase, so there are nulls to the sides. You can have bass in the listening position, but it won’t carry through walls. They are also easy to experiment with. Cut some holes and add some helper woofers. You can use plate amps to drive them. Make replacement center baffles so you can try vintage drivers. Buy a pair of cheap subs from Parts Express, some high efficiency tweeters, take off the wings and try a three-way setup with Betsy as the midrange. Or, leave them alone and spend your time and money on a really good source and amplification.Fullrange drivers and open baffles aren’t the right speakers for everybody. It wouldn’t be any fun to spend dozens of hours gluing hundreds of dollars of birch play into a complicated horn only to find out that you would have been happier with a pair of 70’s JBL L100’s. But the Betsy O.B.s are so cheap and easy; why not give ‘em a shot? Mine aren’t my only speakers, but if I had to choose, they sure could be.