Poultrygeist
Lunatic Member
I plan on carving some phase plugs for the Betsy's from wine bottle corks. That should help smooth out the top end and reduce beaming.
Who is running "Full Range"?
- Thread starter baco99
- Start date
audiozaz
rtfm!? - tl;dr
Good idea. What size is the Betsy's voice coil? It's better when the phase plug comes as close as possible to "filling-in" the hole, a wine cork might be a bit short of that. Some arts&craft supply stores may have some cork stock of different diameter though.
I'm diggin' the burro drawing on that OB! :thmbsp:
az
Here's another picture of the Betsy full range single driver in the folding wing OB. I found some inexpensive piano hinges at Big Lots and they did a good job of sealing the back wave. I understand the original Betsy and Betsy K drivers used exotic banana fiber cones.
The Miniwatt SET ( tiny silver amp ) is shown driving the Betsy's.
Can you explain the enclosure for those subs?
opa1
That's nice. Is that a variovent at the bottom or just a screen to keep the cat out of the port?
dnewma04
The Healer
baco99, if you do a search on "H-frame dipole subwoofers" you'll get some good information. In order for dipole subs to reinforce bass well, tend to need very large baffles and/or EQ. The h-frame design is a compact way to fool the woofer into thinking it's in a bigger baffle than it really is. Couple it with a very high Q driver and you can get pretty nice bass from a compact space with the benefits that go along with dipole operation.
Exactly. I understand the trade-offs, but surely there are designs that come *very* close to giving the effect of the full audio spectrum with the purity of a single source, full range component. It also seems that a single driver with no crossover would allow the amp to run more efficiently because there's no loss due to the crossover. Has anyone measured how much power a typical 2 or 3 way crossover absorbs? Maybe a couple tenths of an amp? I'm just curious.
Also, as much as folks dog Bose, they really have historically made the most use of smaller drivers in complex enclosures. Small drivers with lower mass should be able to produce highs in the 15-17k Hz range. With creative cabinet design, bass can extend down to 80 or so Hz.
Maybe not the best example, but it's a proven concept. I appreciate seeing all of your designs because they give me inspiration to make my own.
I'm thinking of doing something with a 4" driver and transmission line enclosure.
OK. I am familiar with the concept. Thanks for clarifying. Sound is cool. :thmbsp:
Poultrygeist
Lunatic Member
The H-frame is nothing more than an open ended cube with all interior dimensions of 17 inches. The 15 inch Eminence Alpha is mounted on a baffle in the center of the cube. Mine are made from 3/4 inch plywood assembled with pocket hole screws and glue.
opa1
Tenacious
the original Betsy and Betsy K drivers used exotic banana fiber cones.
The ones in the MLTL's are the green hemp matrix cones 2009 models NOS.
opa1
That's nice. Is that a variovent at the bottom or just a screen to keep the cat out of the port?
No cats here. Its just a screen.
I've used model rocket nose cones for phase plugs before
Thats a good idea. I think Planet10 on DiyAudio has phase plugs for them.
I've read good and bad about using them in the Betsy though.
Mark
The ones in the MLTL's are the green hemp matrix cones 2009 models NOS.
opa1
That's nice. Is that a variovent at the bottom or just a screen to keep the cat out of the port?
No cats here. Its just a screen.
I've used model rocket nose cones for phase plugs before
Thats a good idea. I think Planet10 on DiyAudio has phase plugs for them.
I've read good and bad about using them in the Betsy though.
Mark
westend
Audiopile
I've heard the "H" alignment with two Peerless 12"'s in each "H", used for low frequency reinforcement. It was a pretty seamless integration.
Just posted this up in another thread, another single driver creation that I had forgotten.
This is the CSS WR125, first generation in an aperiodic box that my son used for awhile. As a nearfield speaker, the imaging is incredible.
Hey Gary, you should show off those Jordan's to give the OP an idea about the higher end of single-driver.
Just posted this up in another thread, another single driver creation that I had forgotten.
This is the CSS WR125, first generation in an aperiodic box that my son used for awhile. As a nearfield speaker, the imaging is incredible.
Hey Gary, you should show off those Jordan's to give the OP an idea about the higher end of single-driver.
Poultrygeist
Lunatic Member
opal1,
You're right the original Betsy's are hemp cones. The Fostex has the banana fiber.
You're right the original Betsy's are hemp cones. The Fostex has the banana fiber.
gaslover
Active Member
I'm going from open-baffle to no-baffle. Drivers are Dayton PS-220-8" full rangers. I'm building frames and the drivers will be hung inside by lengths of thin wire. The idea is complete dis-association with ANY form of baffle. I high-pass these at 500Hz. Separate sealed box woofers for <500Hz.
Anyone done the no-baffle boogie before? Results??
Anyone done the no-baffle boogie before? Results??
budgetaudio6
Addicted Member
Pioneer PE12. Run full range but it has a super tweeter, Very nice midrange out of that little bugger.
audiozaz
rtfm!? - tl;dr
Nice, I'd like to hear a PE-12 some day. I think few drivers can rival it in terms of relative magnet size.
As of now, I have Fostex FF125K in mini-reflex boxes for computer use, which I plan to replace with the new FF125WK in somewhat larger boxes for more bass. Also have the FF225WK in Karlson SK8 and FF85WK in small backload horns I designed. I have some Richard Allan CG10T and Philips AD7060 sitting in boxes, would like to build something for them, but have no room for more large speakers at the moment.
az
mhardy6647
Lunatic Member
The LS-8 mentioned a coupla posts above is one of my single favorite "FR" drivers. I think that an 8" driver is the 'sweet spot' between LF extension, good sensitivity, and acceptable HF extension and dispersion - I'd consider the very modest little LS-8 (very inexpensive when new and in production for many years) a 'best buy' in the 8" category
It is, I think, no coincidence that my interim daily driver speaker system in MA is a pair of EV Esquire three-ways. The "meat" of the Esquire is an LS-8 employed as a midrange in its own, vented enclosure, augmented at the low end by an EV 12BW woofer (sealed box) and in the treble with a T-35B diffraction horn tweeter. Altec-quality midrange in an inexpensive little box
I am sure you're sick of my touting the R/S 40-1354 5-1/4" twincone as a FR driver... but they are sure sweet (and again, dirt cheap)...
It is, I think, no coincidence that my interim daily driver speaker system in MA is a pair of EV Esquire three-ways. The "meat" of the Esquire is an LS-8 employed as a midrange in its own, vented enclosure, augmented at the low end by an EV 12BW woofer (sealed box) and in the treble with a T-35B diffraction horn tweeter. Altec-quality midrange in an inexpensive little box
I am sure you're sick of my touting the R/S 40-1354 5-1/4" twincone as a FR driver... but they are sure sweet (and again, dirt cheap)...
budgetaudio6
Addicted Member
audiozaz, Its a rather interesting driver in a pretty small sealed box. I have it stuffed so full i guess its more infinite baffle(if thats the correct term for it).
Been putting it to use on my FM/LP rig lately.
Been putting it to use on my FM/LP rig lately.
mhardy6647
Lunatic Member
I am also a lover of the Radio Shack FR. These were given to me by ejfud. Built to the Hawaii plans available online. They await a set of phase plugs from Planet 10.
The Hawaii Five-O (or Five point two-five) from the old Bottlehead magazine ("Valve", I think it was called). It was one of the Bottlehead crew (Doc himself, I think... but maybe it was Paul Joppa) who said of the 40-1354 "it gets the midrange right". It's a beguiling little driver (and it really appreciates a couple of quick and dirty phase plugs from Dave Dlugos - http://www.planet10-hifi.com/pp-info.html).