After hearing the field-coil Lowthers and Feastrexes at RMAF, I wanted to build some kind of simple OB. I had a pair of Visaton B200's in the closet, and decided to build a certain variant of the legendary "Dark Star" OB found here:
Wild Burro Audio Labs - Fullrange Speaker Projects - Basic Open Baffle Design
6moons audio reviews: RoadTour Exit 5 with Michael Lavorgna
I decided to do a shoot-out of the B200's vs. the Betsys, so I ordered a pair which came in just three days. The Betsy is an economical $100 whereas the B200's are about $270 per pair, so any comparison is really about bang for the buck.
Goals
On this thread, I want to (1) give details on the build and the drivers, (2) give listening impressions of each, (3) exchange information with others who may have insight into this interesting and simple design.
Drivers
The Betsy has economy construction compared to the over-engineered cast-aluminum frame B200. The Betsy's magnet is a lot smaller than the B200, but the Q is supposed to be about the same. The Betsy's have a higher Fs than the B200's. But the price difference is enormous.
The Betsy's remind me of the Pioneer BOFU20 -- best bang for the buck for projects on tighter budgets. The Betsy takes a slightly smaller hole than the B200, by the way. So the way to test is to try Betsy's first, then enlarge the hole and try the B200's (or build a removable mount).
Construction
I followed the instructions at the first link above. I decided to go all-out and used expensive 48" piano hinges (so-called continuous hinge available at hardware stores). These cost as much as the Betsy's! In retrospect, I don't recommend piano hinges because:
(a) they are expensive
(b) they overlap the hole, but it worked out okay
(c) there are many, many screws (hundreds)
(d) the hinges still have little gaps so you have to seal them anyway
The piano hinges do give a nice furniture look if you care about that.
I had the lumber yard cut up one sheet of 4'x8' and had scraps left over to make 48" x 1" strips for possible bracing (gluing the strip's grain at 90 degrees to the ply's grain, like an I-beam). But I haven't needed the bracing yet.
I attached the Betsy's with wood screws and installed t-nuts for the (eventual mounting of the) B200 because the B200 is really heavy and the Betsy is lighter. For the B200, I put a single hole at the 12:00 position, but that meant that 4 holes were overlapped by the hinge, so I had to recess the t-nuts into the ply. (Had I rotated the B200 by 30 degrees, only two t-nuts would have been overlapped by the hinge.)
I put a layer of rope-caulk under the Betsy. I usually use silicone, and torquing the screws gets the silicone to squeeze out. Not so with rope caulk, so I wonder if I used too much (it's visibile from the side of the driver).
Suggestion: the middle panel on this design is fine for the Betsy but a bit narrow for the heavier, wider B200.
Amp and Source
We set this up in the living room, not my listening room, so I just used a 2-watt Bottlehead, $39 CD player, $10 interconnects and lamp cord. Ultimately, this design will be hooked up to a laptop / digital EQ / outboard DAC.
Room and Position
Room is 19x14, and they are 4 feet from the wall. I liked the sound with the big wing extended completely, no toe-in.
I sat in a computer chair (on wheels) and rolled around to find the best bass in the room. This design is very sensitive to where you sit, bass-wise.
Tones
Bass: An 80Hz test tone is loud, a 63Hz test tone is louder still (due to Fs), and a 50Hz test tone is audible but way down. With digital EQ, I am guessing that 50Hz tone could be made louder but x-max would limit the overall sound level.
Music
Wow. Absolutely beautiful music, depending on the material. Even without break-in, they surpassed my expectations by a mile. Clear, airy, and (on the right material) effortless. They sing.
Bass is clear and pretty low, although not meaty. It's tuneful, not viceral. If you like acoustic and small ensembles, I think you will absolutely love this design.
They sound best on music that is less dense, e.g. acoustic, voice. Lots of harmonics and dynamics stress them out. Heavy bass is out, but they surprised us with how low they go, when you are sitting in the perfect spot.
There's not so much room ambience, due (I think) to the massive size of the extended baffle, which probably ends up re-reflecting (and delaying) a lot of the backward energy. It made many of my old favorites sound new and interesting.
At RMAF, I heard a couple dozen expensive speakers that did not have the simple, special musical quality of this design.
Absolutely top-notch: Bill Evans, Diana Krall, anything acoustic, small ensembles, guitar and voice.
Excellent: early Miles Davis, Steely Dan, Donald Fagen (a bit bass-shy).
Interesting: Jethro Tull - voice and acoustic instruments sound beautiful, but when the band comes in (e.g. "Thick as a Brick") it sounded compressed. Some of that is due to the amp, though.
Not (Yet) Good: Pablo Casals' solo cello lacked richness and meat, but I think break-in will improve this greatly.
Nit-pik: On most songs, the bass was really clear, but on some songs, depending on the key perhaps, the bass wasn't tight and I think it was due to the song hitting around the driver's Fs, as the 63Hz tone did.
Initial Conclusion
This system is fantastic and affordable! It reminds me of the BiB -- lots of music for a small price and easy build.
So many mega-buck speakers at RMAF failed to impress, but this simple build really delivers a lot of music. No speaker is perfect, but this design has a beautiful musical quality that, like the Bib, you have to hear to believe. Like other fullrangers, it's not going to do a convincing tympani like an Altec VOTT, but it has many positive (and some compelling) qualities of its own.
I will continue breaking in the Betsy's, and then give the B200's a go.
Thank You
A big thanks to my wife, who helped me build and audition them, and to the Santa Fe Audio Society, especially Monte Verde, Serenechaos and Feastrex OB mad scientist Phil Townsend. Thank you to pjanda1 (Betsy maker), and thanks to the generous gurus here, GM, MJK, Scottmoose, Dave Dlugos and too many others to list.
Wild Burro Audio Labs - Fullrange Speaker Projects - Basic Open Baffle Design
6moons audio reviews: RoadTour Exit 5 with Michael Lavorgna
I decided to do a shoot-out of the B200's vs. the Betsys, so I ordered a pair which came in just three days. The Betsy is an economical $100 whereas the B200's are about $270 per pair, so any comparison is really about bang for the buck.
Goals
On this thread, I want to (1) give details on the build and the drivers, (2) give listening impressions of each, (3) exchange information with others who may have insight into this interesting and simple design.
Drivers
The Betsy has economy construction compared to the over-engineered cast-aluminum frame B200. The Betsy's magnet is a lot smaller than the B200, but the Q is supposed to be about the same. The Betsy's have a higher Fs than the B200's. But the price difference is enormous.
The Betsy's remind me of the Pioneer BOFU20 -- best bang for the buck for projects on tighter budgets. The Betsy takes a slightly smaller hole than the B200, by the way. So the way to test is to try Betsy's first, then enlarge the hole and try the B200's (or build a removable mount).
Construction
I followed the instructions at the first link above. I decided to go all-out and used expensive 48" piano hinges (so-called continuous hinge available at hardware stores). These cost as much as the Betsy's! In retrospect, I don't recommend piano hinges because:
(a) they are expensive
(b) they overlap the hole, but it worked out okay
(c) there are many, many screws (hundreds)
(d) the hinges still have little gaps so you have to seal them anyway
The piano hinges do give a nice furniture look if you care about that.
I had the lumber yard cut up one sheet of 4'x8' and had scraps left over to make 48" x 1" strips for possible bracing (gluing the strip's grain at 90 degrees to the ply's grain, like an I-beam). But I haven't needed the bracing yet.
I attached the Betsy's with wood screws and installed t-nuts for the (eventual mounting of the) B200 because the B200 is really heavy and the Betsy is lighter. For the B200, I put a single hole at the 12:00 position, but that meant that 4 holes were overlapped by the hinge, so I had to recess the t-nuts into the ply. (Had I rotated the B200 by 30 degrees, only two t-nuts would have been overlapped by the hinge.)
I put a layer of rope-caulk under the Betsy. I usually use silicone, and torquing the screws gets the silicone to squeeze out. Not so with rope caulk, so I wonder if I used too much (it's visibile from the side of the driver).
Suggestion: the middle panel on this design is fine for the Betsy but a bit narrow for the heavier, wider B200.
Amp and Source
We set this up in the living room, not my listening room, so I just used a 2-watt Bottlehead, $39 CD player, $10 interconnects and lamp cord. Ultimately, this design will be hooked up to a laptop / digital EQ / outboard DAC.
Room and Position
Room is 19x14, and they are 4 feet from the wall. I liked the sound with the big wing extended completely, no toe-in.
I sat in a computer chair (on wheels) and rolled around to find the best bass in the room. This design is very sensitive to where you sit, bass-wise.
Tones
Bass: An 80Hz test tone is loud, a 63Hz test tone is louder still (due to Fs), and a 50Hz test tone is audible but way down. With digital EQ, I am guessing that 50Hz tone could be made louder but x-max would limit the overall sound level.
Music
Wow. Absolutely beautiful music, depending on the material. Even without break-in, they surpassed my expectations by a mile. Clear, airy, and (on the right material) effortless. They sing.
Bass is clear and pretty low, although not meaty. It's tuneful, not viceral. If you like acoustic and small ensembles, I think you will absolutely love this design.
They sound best on music that is less dense, e.g. acoustic, voice. Lots of harmonics and dynamics stress them out. Heavy bass is out, but they surprised us with how low they go, when you are sitting in the perfect spot.
There's not so much room ambience, due (I think) to the massive size of the extended baffle, which probably ends up re-reflecting (and delaying) a lot of the backward energy. It made many of my old favorites sound new and interesting.
At RMAF, I heard a couple dozen expensive speakers that did not have the simple, special musical quality of this design.
Absolutely top-notch: Bill Evans, Diana Krall, anything acoustic, small ensembles, guitar and voice.
Excellent: early Miles Davis, Steely Dan, Donald Fagen (a bit bass-shy).
Interesting: Jethro Tull - voice and acoustic instruments sound beautiful, but when the band comes in (e.g. "Thick as a Brick") it sounded compressed. Some of that is due to the amp, though.
Not (Yet) Good: Pablo Casals' solo cello lacked richness and meat, but I think break-in will improve this greatly.
Nit-pik: On most songs, the bass was really clear, but on some songs, depending on the key perhaps, the bass wasn't tight and I think it was due to the song hitting around the driver's Fs, as the 63Hz tone did.
Initial Conclusion
This system is fantastic and affordable! It reminds me of the BiB -- lots of music for a small price and easy build.
So many mega-buck speakers at RMAF failed to impress, but this simple build really delivers a lot of music. No speaker is perfect, but this design has a beautiful musical quality that, like the Bib, you have to hear to believe. Like other fullrangers, it's not going to do a convincing tympani like an Altec VOTT, but it has many positive (and some compelling) qualities of its own.
I will continue breaking in the Betsy's, and then give the B200's a go.
Thank You
A big thanks to my wife, who helped me build and audition them, and to the Santa Fe Audio Society, especially Monte Verde, Serenechaos and Feastrex OB mad scientist Phil Townsend. Thank you to pjanda1 (Betsy maker), and thanks to the generous gurus here, GM, MJK, Scottmoose, Dave Dlugos and too many others to list.
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I found that out when i tried to fit Betsy into the removable baffles the B200s used to be in....
I look forward to the rest of your journey. Pictures?
In another thread i said you were going to have to splurge to hit $200. Guess that was the piano hinge.
dave
Hi folks,
The drivers are breaking in really fast (wife thrashed them all day). Yesterday, when I walked into the other room, the speakers were very bass-shy, but now, listening from the other room, they have much more bass.
1. Dire Straits - Communique: wow, almost perfection, Knopler's strat sounds clear as a bell, bass and kick drum are fat and full (although it's still not, and never will be, visceral).
2. Solo cello - beefy! Casals was vastly improved, and Janos Starker's cello was rich and full of harmonics and scraping sounds, sounded life-sized (lots of breathing and thumping on that recording).
3. Jethro Tull - "Aqualung" and "Thick as a Brick" are starting to sound good at the dynamic parts. Electric guitar sounds great. Who knew that guy made so many weird talking-noises when he plays the flute? (And what the heck are those songs about?)
4. Donald Fagen, Kamakiriad and Morph the Cat: bass and kick are ample, no complaints.
5. Jane Monheit, Live at the Rainbow Room: Ron Carter's bass is very clear, with each note distinct, but light in weight. Still, the notes are there and that wasn't the case yesterday.
All this is without any digital EQ. Eventually, with more break-in and some EQ, I think everything could be ironed out (as much as possible with a single fullranger).
Two tricky bits:
* It takes time to find the listening spot where (a) bass is best and (b) the stereo image is perfect. Lots of little tweaking is required.
* The speakers are mounted low, so sitting in a computer chair is way too high for this design. Sitting high makes the players sound small, but this is easily corrected by listening more on axis (i.e. sitting on the couch).
Dave, I will try to take pix (I don't own a camera at the moment) and yes, the hinges were a regrettable budget-killer.
Serenechaos, pizza awaits you! Human.bin, I will keep Casals at the forefront. Godzilla, I know you will appreciate these drivers and this design.
The drivers are breaking in really fast (wife thrashed them all day). Yesterday, when I walked into the other room, the speakers were very bass-shy, but now, listening from the other room, they have much more bass.
1. Dire Straits - Communique: wow, almost perfection, Knopler's strat sounds clear as a bell, bass and kick drum are fat and full (although it's still not, and never will be, visceral).
2. Solo cello - beefy! Casals was vastly improved, and Janos Starker's cello was rich and full of harmonics and scraping sounds, sounded life-sized (lots of breathing and thumping on that recording).
3. Jethro Tull - "Aqualung" and "Thick as a Brick" are starting to sound good at the dynamic parts. Electric guitar sounds great. Who knew that guy made so many weird talking-noises when he plays the flute? (And what the heck are those songs about?)
4. Donald Fagen, Kamakiriad and Morph the Cat: bass and kick are ample, no complaints.
5. Jane Monheit, Live at the Rainbow Room: Ron Carter's bass is very clear, with each note distinct, but light in weight. Still, the notes are there and that wasn't the case yesterday.
All this is without any digital EQ. Eventually, with more break-in and some EQ, I think everything could be ironed out (as much as possible with a single fullranger).
Two tricky bits:
* It takes time to find the listening spot where (a) bass is best and (b) the stereo image is perfect. Lots of little tweaking is required.
* The speakers are mounted low, so sitting in a computer chair is way too high for this design. Sitting high makes the players sound small, but this is easily corrected by listening more on axis (i.e. sitting on the couch).
Dave, I will try to take pix (I don't own a camera at the moment) and yes, the hinges were a regrettable budget-killer.
Serenechaos, pizza awaits you! Human.bin, I will keep Casals at the forefront. Godzilla, I know you will appreciate these drivers and this design.
>>> Who knew that guy made so many weird talking-noises when he plays the flute?
LOL! One of the drawbacks of many of the speakers we build is that our quest for the best returns our efforts with everything on the recording... including the parts we'd rather not hear. I wonder if you will hear even more of this with the B200? One can argue you're getting closer to the performers and their performance... no argument there... but it could be distracting. I cracked up when i read your comment btw. Thanks for the cheerful laugh! I needed one today.
Godzilla
PS, i am listening to a pair of KLH i found in the trash. These speakers are probably 30 years old and sound pretty bad BUT playing in the background they sound pleasant enough and provide atmosphere in my quiet office.
http://www.zillaaudio.com/klh.htm
Never will i be able to hear the "weird talking-noises" or grunts from jazz keyboardists thru these old KLH... but i consider that a good thing while trying to concentrate at work. Listening in my home thru my BIBs i want to be transported to the venue where every little detail is much more welcome and adds to the experience. Good to know the Betsy's will get me there too. Thanks again for your listening impressions.
LOL! One of the drawbacks of many of the speakers we build is that our quest for the best returns our efforts with everything on the recording... including the parts we'd rather not hear. I wonder if you will hear even more of this with the B200? One can argue you're getting closer to the performers and their performance... no argument there... but it could be distracting. I cracked up when i read your comment btw. Thanks for the cheerful laugh! I needed one today.
Godzilla
PS, i am listening to a pair of KLH i found in the trash. These speakers are probably 30 years old and sound pretty bad BUT playing in the background they sound pleasant enough and provide atmosphere in my quiet office.
http://www.zillaaudio.com/klh.htm
Never will i be able to hear the "weird talking-noises" or grunts from jazz keyboardists thru these old KLH... but i consider that a good thing while trying to concentrate at work. Listening in my home thru my BIBs i want to be transported to the venue where every little detail is much more welcome and adds to the experience. Good to know the Betsy's will get me there too. Thanks again for your listening impressions.
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what were those lyrics about? you probably don't really want to know - let's just say if they became teleplays, you be finding them on HBO, along with Dexter, True Blood, Durham County -
OT for a minute -this somehow reminds me of a very interesting, "slightly(?) dark" film I caught a few weeks back - "The Jacket" with Adrian Brodie, Kiera Knightly and Kris Kristofferson.
Keith Jarret is a fantastic artist, but can the Live venue recording engineers please do something about that mike placement? Scatting along with the instrument is fine, if the artist can hold a tune - can you say Esperanza Spalding?
Hi folks!
Godzilla, you are the luckiest guy on earth, just /finding/ stuff like that. Chris, now I'm more curious than ever about "Thick as a Brick." Serenechaos, I don't have that album but when you see my CD player, you might have second thoughts (it's junk and the door sometimes has to be pried open). I'll have to get something better for the listen.
More to report:
1. I think the Betsy's break in really fast, and are mostly there. Bass is great! Overall, they are now excellent on about 90% of the material that I like, and only have a touch of something in the upper midrange on e.g., lush Steely Dan harmonies, but that's life with a fullrange sometimes.
2. Janos Starker's solo cello is the best thing yet. Captivating. Haunting. Really there in the room. There is gobs of bass for music like this. On the very lowest notes, I thought the baffle was resonating (or was it the cello, or a slight room mode from the space he was in? It was just on one note, so too quick to tell from the couch The realism is incredible to me.
3. One reason why the baffle doesn't resonate more could be the over-abundance of rope caulk.
4. This design might work so well because the room is a concrete slab with a thin carpet, and the front wall (the wall you face) is mostly a big brick fireplace.
5. Any limited dynamics could be blamed on the little 2-watt Bottlehead but I never go above noon with its volume. Still, that's practically no headroom. The Betsy's are decently efficient (specs say 92.4 db).
5. My life now consists of waking up early to hear the Betsys, rushing to work, rushing back for a 20-minute listening session at lunch, then back to work, then long listening into the night with the lady of the house. All my records are new again. Oh, and the best thing: I haven't watched any television since the Betsy's started making music. No more having CNN on in the background -- that TV may end up in the garage.
This weekend, we're varnishing them, and then it's time to try the B200's.
Godzilla, you are the luckiest guy on earth, just /finding/ stuff like that. Chris, now I'm more curious than ever about "Thick as a Brick." Serenechaos, I don't have that album but when you see my CD player, you might have second thoughts (it's junk and the door sometimes has to be pried open). I'll have to get something better for the listen.
More to report:
1. I think the Betsy's break in really fast, and are mostly there. Bass is great! Overall, they are now excellent on about 90% of the material that I like, and only have a touch of something in the upper midrange on e.g., lush Steely Dan harmonies, but that's life with a fullrange sometimes.
2. Janos Starker's solo cello is the best thing yet. Captivating. Haunting. Really there in the room. There is gobs of bass for music like this. On the very lowest notes, I thought the baffle was resonating (or was it the cello, or a slight room mode from the space he was in? It was just on one note, so too quick to tell from the couch
The realism is incredible to me.3. One reason why the baffle doesn't resonate more could be the over-abundance of rope caulk.
4. This design might work so well because the room is a concrete slab with a thin carpet, and the front wall (the wall you face) is mostly a big brick fireplace.
5. Any limited dynamics could be blamed on the little 2-watt Bottlehead but I never go above noon with its volume. Still, that's practically no headroom. The Betsy's are decently efficient (specs say 92.4 db).
5. My life now consists of waking up early to hear the Betsys, rushing to work, rushing back for a 20-minute listening session at lunch, then back to work, then long listening into the night with the lady of the house. All my records are new again. Oh, and the best thing: I haven't watched any television since the Betsy's started making music. No more having CNN on in the background -- that TV may end up in the garage.
This weekend, we're varnishing them, and then it's time to try the B200's.
There isn't much I can add here, as I'm glad that you're enjoying them!
RJBond and I talked a bit via email about messing with the Qts via wire and resistors. I am testing some prototype TL's (for the BetsyK). Initially I was amazed at how much bass they were producing, but it seemed over the top. I swapped the Cat5 speaker cable I had in the system for the OB's to my reference wire (Jon Risch's cross connected Belden 89259 coax recipe) and I couldn't believe the difference. This is what I expected to hear. Most wire is cheap, and certainly worth playing with. I often feel that the OB's are a little "plump" sounding. I need to try the bigger wires.
You noticed that the Betsy's smoothed out pretty quickly, which is partially the driver, but greatly due to the application. As OB's don't restrict excursion at all, the driver sees much more action than it would in a boxier application. I try to break all my drivers in in free air or on OB's. The little TLs I just erected for the BetsyK's, for example, keep excursion well controlled, so the drivers spent a day and a half getting pounded on my test bench.
I have used rope caulk, but on a recommendation from someone here, I find that less rigid driver mounting sounds better. It doesn't make any sense to me, but I get a better midrange with closed cell foam and mounting bolts backed off a 1/4 turn from snug. Whatever you do, keep it the same for both drivers so the comparison will be fair!
I haven't played with it, but folks also seem to experience significant changes with stuff applied to the back of the baffles. I suspect the difference will be lessened when you leave the big wing straight out. The Darkstar guys seemed to like cork. A gent just posted on my blog that he likes "Frostking Duct Insulation".
I choose a steel basket for many reasons. I want to maximize price/performance, but also make a driver that didn't look like it prioritized eye candy over engineering. The Visaton will be really well built, but not all drivers are as carefully assembled as the Betsy! I honestly can't hear a difference with the basket. Those that are worried about it can certainly glue stuff on to their hearts content.
That being said I just ordered a sample of a prettier cast basket for a prototype. If the steel basket is a deal-breaker for any of you out in lurking land, let me know. It is one aspect of the design that is fairly easy to change (which isn't to say that I will, but I'd still like any feedback).
As usual, I meant to just make a brief comment and typed a chapter. Thanks for the kind words re: Betsy. Hopefully the USPS will deliver 'Zilla's pair today! They better bring my new trumpet mouthpiece and my wife's reeds . . .
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
RJBond and I talked a bit via email about messing with the Qts via wire and resistors. I am testing some prototype TL's (for the BetsyK). Initially I was amazed at how much bass they were producing, but it seemed over the top. I swapped the Cat5 speaker cable I had in the system for the OB's to my reference wire (Jon Risch's cross connected Belden 89259 coax recipe) and I couldn't believe the difference. This is what I expected to hear. Most wire is cheap, and certainly worth playing with. I often feel that the OB's are a little "plump" sounding. I need to try the bigger wires.
You noticed that the Betsy's smoothed out pretty quickly, which is partially the driver, but greatly due to the application. As OB's don't restrict excursion at all, the driver sees much more action than it would in a boxier application. I try to break all my drivers in in free air or on OB's. The little TLs I just erected for the BetsyK's, for example, keep excursion well controlled, so the drivers spent a day and a half getting pounded on my test bench.
I have used rope caulk, but on a recommendation from someone here, I find that less rigid driver mounting sounds better. It doesn't make any sense to me, but I get a better midrange with closed cell foam and mounting bolts backed off a 1/4 turn from snug. Whatever you do, keep it the same for both drivers so the comparison will be fair!
I haven't played with it, but folks also seem to experience significant changes with stuff applied to the back of the baffles. I suspect the difference will be lessened when you leave the big wing straight out. The Darkstar guys seemed to like cork. A gent just posted on my blog that he likes "Frostking Duct Insulation".
I choose a steel basket for many reasons. I want to maximize price/performance, but also make a driver that didn't look like it prioritized eye candy over engineering. The Visaton will be really well built, but not all drivers are as carefully assembled as the Betsy! I honestly can't hear a difference with the basket. Those that are worried about it can certainly glue stuff on to their hearts content.
That being said I just ordered a sample of a prettier cast basket for a prototype. If the steel basket is a deal-breaker for any of you out in lurking land, let me know. It is one aspect of the design that is fairly easy to change (which isn't to say that I will, but I'd still like any feedback).
As usual, I meant to just make a brief comment and typed a chapter. Thanks for the kind words re: Betsy. Hopefully the USPS will deliver 'Zilla's pair today! They better bring my new trumpet mouthpiece and my wife's reeds . . .
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
Exactly my experience swapping out Cat5 for cheap white extension cord speaker cable. I just replaced one side; was going to sit back and to see if I could hear the difference from one side to the other.
My wife was in the next room and ask what the change was; "did you change tubes, or an amp or what?" So much for Cat5s in that context...
More than the basket I'd love to see these with some work on the motor. A little bit of pole extension and some shorting paths go a long way. I'd like to see an extended, undercut pole with a single shorting ring around the base, like image 5b with a ring below the undercut. Motor Types
Then you'd have me a-hoppin' to snag some betsys.
Of note, I did a little modeling- both betsy and betsy k work well in a large sealed cab (assuming one knows they won't get sub-bass) and a big (4ft+) vented cab with betsy k strikes a very nice balance between extension and sensitivity, though output is necessarily limited.
Or even far more work done than shown on that web page!
And adjustable Q!
And affordable!
seemingly impossible, but not too much to ask?
this is exciting...
Good news to report. Betsy now goes down to 40Hz (initially, 50Hz was the lowest I could hear before break-in.) It's low but audible. I wish I had a (cheap) measurement kit.
Serenechaos, I would love it if you brought an Azurahorn (and your evil grin I've never seen one in person. That would be a great thing to hear Betsy through.
Pjanda1, thank you for the good advice! So you play trumpet /and/ trombone?
Serenechaos, I would love it if you brought an Azurahorn (and your evil grin
I've never seen one in person. That would be a great thing to hear Betsy through.Pjanda1, thank you for the good advice! So you play trumpet /and/ trombone?
>>> Hopefully the USPS will deliver 'Zilla's pair today!
I got them and have been listening all day. They sound very good in sealed boxes. Compared to Pioneer B20... well, there really is no comparison. I am going to try to get my OBs all cut up this weekend and hear them on what they were designed for.
Godzilla
I got them and have been listening all day. They sound very good in sealed boxes. Compared to Pioneer B20... well, there really is no comparison. I am going to try to get my OBs all cut up this weekend and hear them on what they were designed for.
Godzilla
Badman, I'm not excited about doing a shorting ring. I know it would lower distortion, but it would also give about 5db of treble rise with most amps. I've tried it, and without a compensation circuit, it makes my ears bleed. Some folks love that sound. Others will happily use a circuit. From what I've heard, most of my customers want a driver that they can implement without filters and get reasonably flat response in room (which I find it was happens with the current on axis rise).
If you guys want something in particular, let me know. If five or so of you want a shorting ring on the current motor design, we could talk.
I know I need to get the site updated. I should at least include some enclosure designs for the BetsyK, as the selection has grown considerably. I think the BetsyK really shines in cabinets that have a little more gain and excursion control than a standard vented box. I really like the little TL (12x13x44") in just tossed together. I need to assemble the second pair with a bit different folding, as they didn't end up tuned as low as I had hoped.
RJBond: Everybody and every room is different, so that is why I'm hesitant to answer "extends down to XXhz." The Radio Shack SPL meter (less response at the low end, see google for correction tables) and internet test tones may not be professional, but can certainly provide entertainment and enlightenment.
'Zilla: I'm jealous. This big snow (now over a foot on the ground with wind) seems to be keeping the USPS away from my door.
I spent a couple of degrees and a few years following trying to be an orchestral trombonist. It certainly lost its luster. Now I have dreams of being a weekend warrior lead trumpet player. I haven't seen anybody double trumpet and trombone. I know some commercial guys pull it off, but at this point, I'm just trying to form some trumpet chops.
I hope I'm not hijacking the thread! I'm as curious as anyone to hear how the B200 fairs. gotta make some custard,
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
If you guys want something in particular, let me know. If five or so of you want a shorting ring on the current motor design, we could talk.
I know I need to get the site updated. I should at least include some enclosure designs for the BetsyK, as the selection has grown considerably. I think the BetsyK really shines in cabinets that have a little more gain and excursion control than a standard vented box. I really like the little TL (12x13x44") in just tossed together. I need to assemble the second pair with a bit different folding, as they didn't end up tuned as low as I had hoped.
RJBond: Everybody and every room is different, so that is why I'm hesitant to answer "extends down to XXhz." The Radio Shack SPL meter (less response at the low end, see google for correction tables) and internet test tones may not be professional, but can certainly provide entertainment and enlightenment.
'Zilla: I'm jealous. This big snow (now over a foot on the ground with wind) seems to be keeping the USPS away from my door.
I spent a couple of degrees and a few years following trying to be an orchestral trombonist. It certainly lost its luster. Now I have dreams of being a weekend warrior lead trumpet player. I haven't seen anybody double trumpet and trombone. I know some commercial guys pull it off, but at this point, I'm just trying to form some trumpet chops.
I hope I'm not hijacking the thread! I'm as curious as anyone to hear how the B200 fairs. gotta make some custard,
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
I could go for a Alnico version. The cast basket would be nice if it could be shaped with ovalish Xsections for strength and to abate back wave interference. If a shorting ring = rising fq + correction network, really Wⓓon't mind if you sit this one out.
I'm seriously liking that they can perform O.B. without additional amplification + bass driver.
If you do alnico count me in as one of the five.
I'm seriously liking that they can perform O.B. without additional amplification + bass driver.
If you do alnico count me in as one of the five.
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