CommonSense Audio's website is chock-full of information on creatingProjectsusing Full Range Loudspeaker Drivers using 45 years ofexperiences. Common Sense Audio distributes Lowther, Fostex and PAudio Drivers. / CommonSense Audio which also Manufactures Audio Nirvana drivers.
The only FullRange driver larger than 8' diameter. Audio Nirvana speakers areavailable in 3 inch (76mm), 6.5 inch (165 mm), 8 inch (200 mm), 10 inch (250mm), 12 inch (300 mm), and 15 inch (380 mm) sizes. Common Sense Audio has 45 years of experience with Loudspeakers.Hawthorne Audio produces stunning designs with Open / Infinite Baffles that have to be seen.(US Enclosure has no business association of any nature with these cited companies). The closed box (acoustic suspension) and the vented box (bass reflex)cabinets are common designs for multi-way speakers. These designs can be appliedto single full range drivers but their effectiveness depends on the nature ofthe driver.
Some drivers such as Mitsubishi/Diatone 610, the Hammer Dynamics,and some Fostex drivers have enough cone excursion so that they work well in boxcabinets (usually vented/bass reflex). Diatone/MitsubishiThe Diatone kit EIFL offers is made of particle board. It is similarto theJPO Memorial (made by Wavelength Audio), I guess, although smaller. Aproject is based on Mitsubishi's original plans, and is quitecomplicated; essentially, it uses a box of 1/2' birch plywood insideanother boxof 5/8' plywood; the two boxes are separated by wooden floorboards, oneto aside.
Fostex Fe103
In the original Mitsubishi plan, the 'inside box' does not extendto thefront panel; but it does include the rear panel. The French guy didn'tfollowthe rear part exactly - in fact, in his plan, the rear panel isremovable!Damping is supposed to be natural wool.This box design originated with Hiroyasu Kondo and the scans are froml'Audiophile.
The enclosure is designed specifically for the Diatone 610 in 8 or16 Ohm. The low end should extend to 40Hz or so. I suspect that a Pioneer PM-16Memorial should work too. FostexMany Fostex drivers are suitable for closed or vented boxes, including theFX200 and the F200A. Fostex has many plans for vented box speakers on theirwebsite for Fostex full range drivers. David WeemsBass reflex box (design by Weems) in an article using Radio Shack drivers inValve Magazine, Vol 6, No 4, 1999 at.
Includes constructionplans. Jordanhas designed many greatfull range drivers, the latest in the Jordan line include the JX-92S which canbe used in a vented box or transmission line. (Go to the and click on Systems. RehdkoInfo from Ulli (thanks). These loudspeakers are made by Rehdko in France.There are three models: RK 115 has one 26 cm full-range driver, RK 125 has one26 cm full-range driver and one elliptical tweeter (12 x 19 cm). The big RK 145has one full-range woofer (26 cm), 1 high midrange (12 x 19 cm) with REHDKO'saucer', one elliptical tweeter (12 x 19 cm) with supra-dispersion (with thefamous REHDKO 'saucer').
Ulli has heard all three types and says that even thesmallest speaker sounds more natural than a Lowther DX in the Audiovector. Smallwrite ups appear at.
PHY-HPin a baffle.Lowther Bass Reflex SpeakersLowther drivers need help in the bass region due to their strongly risingfrequency response. For a full range speaker, a rear-loaded horn is usually thebest option. Some people claim good results with Lowthers in bass reflex boxes,while others who have tried or heard them find them terrible. If your room is'live' and has lots of reinforcement in the bass region, or your music tastedoesn't require full volume bass, they might work.
Some optimized vented boxmight be better than poorly-designed or executed rear horns. In any case, youwill need to hear the loudspeaker in your room to get a genuine answer. Searchthe (in Speaker Asylum and in High Efficiency Asylum) for 'bass reflex'and Lowther, or under 'Classic Audio' to find a large amount of opinion(informed or otherwise!).Recently a review appeared here atwhich was quite negative, and resulted in some discussion on the. (Search onDicks, or Classic Audio).Full-range Driver & Loudspeaker TheoryFull-range (or wide-range) drivers come in two general types: the center capand the whizzer cone. The center cap type looks like your normal cone speakerwith a dome center cap. The whizzer cone type has two cones, a large cone (as innormal cone speakers) and a smaller whizzer cone inside the large cone.
Fostex Speaker
Driverunits have quite different characteristics depending on the design andmanufacturer. Some (like Lowther) have very high efficiency, low excursion, anda frequency response graph that shows lowered sound pressure levels at medium tolow bass (below 400 Hz). For this reason, to be an effective full range speaker,these drivers usually need special cabinet construction designed to enhance thebass output, such as a rear-loaded horn.
However, the high efficiency allows theuse of very low power amplifiers (such as a two Watt 2A3 tube amp). Otherdrivers have lower efficiency but flatter frequency response. These drivers canoften be used in an open baffle or bass reflex cabinet, but require higheramplifier power to drive them.There are very few true full range drivers that radiate from one source.
TheDiatones almost qualify, but are a bit weak in the bass, and a little weak inthe highs. Some old drivers such as the Goodmans Axiom 80s, and maybeTelefunkens and Norelcos and others go down to low bass (30s) and pretty high(12 - 16 kHz) making them more full range. These all radiate 'from the frontcone', making a true point source and having no or little time delay errors.Finding or making these drivers is very difficult. Most 'full-range' drivers endup needing two radiation sources, one for low and one for high frequencies.Lowther drivers, for example, radiate the high and mid frequencies from thecone, but the bass come out of a horn and are delayed in time and 180 degreesout of phase, as well as coming from the horn mouth rather than from the cone.So in a way, you have two frequency sources, with a crossover between them. Thecrossover is acoustic and needs to be tuned properly, and at the crossoverfrequency there is still potential for interaction of the two wave fronts.Another option with a Lowther-style radiator (which goes from high to midfrequencies) is to add a separate bass system. Bert Doppenberg's Oris 150 fronthorn for Lowthers needs a separate bass system, Bert uses bass horns withdedicated drivers. Subwoofers might work but are often not 'fast' enough tointegrate properly.
This philosophy puts the (one) crossover at the lowfrequencies (150 - 200 Hz for Bert's, approx 300 Hz for most rear-loaded Lowtherdrivers).Another philosophy puts the crossover frequency high up, at 12 kHz, or 15kHz, the higher the better. This method uses a driver that runs from low bass(30 or 40 Hz say) all the way up to the crossover frequency (10.5 kHz say), thenlets a supertweeter take over from there. The big question is, where is itbetter to put a crossover? Low frequencies or high?A second question is, what kind of bass do you like? Horn-loaded bass(whether from a Lowther horn or a dedicated bass horn) is regarded as being'fast', having good transient response characteristics, a very natural sound.Direct radiators have a harder time making that kind of bass. Bass drivers withlong throws and polypropylene cones are particularly bad. A bass driver conemade from paper (or sometimes kevlar or other modern material) often soundsbetter.
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But a full-range driver such as a Diatone cannot have too large adiaphragm and also cannot have too large a cone movement (xMax) becauseotherwise high frequencies will be attenuated and intermodulation distortionwill result from the long throw. However, to make more bass, you can increasethe surface area (cone size) without increasing the travel (xMax). Now you canhave more bass and higher treble without too much intermodulation distortion, aslong as you can control the larger cone (need good design for the cone). Withthe shorter travel, bass will become more controlled, crisper and moreresponsive compared to a long travel bass driver. (You won't get as much bassout, but it will sound nice).Cone material can be made from paper (the classic material), plastic (oftenpolypropylene), synthetic fiber/resin such as kevlar, and metal (oftenaluminium).
Paper tends to have less stiffness than some other materials (kevlarand metal) but doesn't exhibit the ringing resonance often found in kevlar andmetal. Some paper cones can be stiffened up with varnish-like substances such asDamar. Good discussion on driver theory is. Some excellentarticles by Lynn Olson on and speaker drivers (along with some tube thoughts). Physics of Full Range Drivers By John WyckoffAny attempt to explain full range cone-and-coil loudspeakers must begin withthe fact that there is no such thing.
Rather, such drivers are systems of two ormore drivers on the same motor assembly. This may seem to be splitting hairs,but it is a very important concept in understanding drivers designed to operatefull range. The two basic formats for full range drivers are whizzer cone andcenter cap type.
In either case, there is going to be a substantial peak in thefrequency response where the main cone and secondary device are both active.This spike is most easily understood in the case of the central dome typedriver, such as the JBL LE8T-H. If a measurement is taken of the physical widthof the dome, and that measurement is then converted to a wavelength, it may beseen that the co-resonance of the main cone and the dome is 6.1k Hz. Ameasurement microphone will confirm this. This spike is fairly narrow in Q, butabout +7 dB in height. A secondary resonance is created at the half wave pointas well, or where the dome equals one half of 3.05 kHz. This resonance is lowerin amplitude, and can be heard as 'glare'.
In the case of the whizzer, or freecone driver, the exact point of resonance is more difficult to find with aruler, but is still just as prevalent.A free cone has many additional problems for the designer to overcome whencompared to a center cap type. Free cones have radiating surfaces which are notin phase with each other, nor do the inner and outer surfaces receive the sameair loading ( I've measured free cones which have 90 degree phase shift). Theinside of the free cone is its own conical horn, while the outside is hornloaded by the main cone, which is an entirely different horn formulation.Anomalies also result from the outer edge of the free cone as the front and rearwaves collide along this diffractive edge.When the above difficulties are added to the other resonances within thedriver; such as: fundamental resonance, cone resonance, and free-cone or domeresonance, the design job begins to look impossible. While good qualitybroadband drivers do exist, finding the right compromises is one of the mostdifficult problems in audio. For example, if enough mass is added to the maincone to reduce the cone resonance, the higher frequencies will be attenuated. Sonu nigam sad songs download.
Ifthe cone is too light, it probably won't be strong enough to act as much of apiston at low frequencies. A driver which has enough excursion to offer dynamicbass, will exhibit higher intermodulation distortion. Full range driver systemsare not a bass driver with a whizzer.As mentioned before, there are more anomalies with the free cone approachthan with a central dome, yet free cones predominate. This is because they offermuch greater dispersion, and more adjustability. The Hammer Dynamics Super 12drivers are of free cone and center dome design, to extend the bandwidth as muchas possible.
This third device offers challenges of its own.Many smaller broadband drivers (200mm and under) are rear loaded into horns,in order to extend bass. There are several problems related to this type ofloading: Size, delay, coloration, and the fact that this approach is theapplication of feedback. Striving to produce amplifiers without feedback, andthen introducing it into the speaker design, seems odd engineering. Whizzer Cones by MG (from a Full Range Forum post)Whizzer cones were originally an afterthought to extend the high frequencyresponse of midrange cones. Midrange paper cones absorb the flexural wave as ittravels out from the voice coil. This means that there is a reduction inradiating area and high frequency response.
Since the wave speed is proportionalto the square root of frequency this usually ends up being a 1st order roll off,but please don't ask me to explain this in detail in a simple posting!The midrange of paper cones can be extended by flaring the cone, so that thecentre is mildly horn loaded, this gets you up to about 5kHz. The whizzer isflared to fit inside the main cone, and can sometimes be be used to horn loadthe area between the whizzer and the cone. Normal DIY practice is to fiber woolfill this region to avoid higher frequency cancellation.By being light and stiff, the whizzer does not greatly affect the working ofthe main cone, the flexural wave traveling out from the voice coil pretty muchunattenuated. This means that the high frequency can now be radiated over a muchlarger area, and hence the response is extended. The front of the whizzer doesnot horn load the centre, although the shape will affect high frequencydispersion.Since the whizzer is unconstrained around the edges some cone modes canoccur, although half roll surrounds do not damp these out as much as peoplewould like to believe.
The best trick for this is to silicon fluid damp bothpaper cones - since the whizzer is much thinner it will absorb much less siliconfluid, so its high frequency response will not be greatly attenuated. Criticaldamping of the spider is also very successful at eliminating these, but canincrease the mechanical damping Qms parameter.Understanding of diaphragm flexure has led to a new generation ofwhizzer-less full range designs, the pinnacle being the Jordan JX series. For mymoney these represent the ultimate cone flexure technology, but there are manyother available drivers. Increasing practice is to use the same passiveelectrical network, used for baffle step correction, to extend the highfrequency response - although this is limited to about 1/2 an octave.End of Full range driver website information cited.Open and Infinite Baffle Cabinets.
The Frugal-Horns Site - High Performance, Low Cost DIY Horn DesignsHome22september15IntroductionFrugal-Horn.com is a homeof high-performance, low-cost (ie frugal) diy horn designs.The resurgence of interest in full range speakers has led to a renewed explorationof the rear-loaded horn. This coupled with a whole new generation of more advancedcomputer-based modeling tools have given designers more power to generate betterdesigns.F rugal-Horn.comstarted in 2006 as a place to gather together a collection of some of the betterdiy horn enclosures. This update brings the entire 3 horn Frugel-Horn family &new Spawns to the site.An estimated 1,000+ have beenbuilt by the diy hifi community. FH3 been shown to work witha wide variety of drivers.
The FH3 has been followed by a larger and smaller. Independent cottage industryand bespoke finished Frugel-Horns has started up in Canada (North America), UK, Australia,& The Netherlands. More are being encouraged.A of a commercial FH3 build/system.With Fostex doing a complete revision of their popular full-ranges, most of the Spawnof Frugel-Horn became obsolete. We now have a new set of Olson/Nagaoka Double MouthManifold Horns for the Fostex FExx6En series of drivers. The new Fostex FFxx5wk seriescan be used in the old mBVR (Changs) but we are looking at optimising for these.DerekSanderson's Sachiko's with Fostex FE206eS-RRear/Back horns (RLH/BLH), with therear of the driver loaded by a bass horn, help a full range driver produce more basswith less work, extending the range closer to the holy grail of 10 octave performanceand providing startling dynamics.
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