This tweeter employs seass highly efficient hexadym magnet structure patent pending, a ring of six small, radially magnetized neodymium magnets in a focused hexagonal array. Wellknown speaker designer joe dappolito has designed much of ushers line. D and is a member of the audio engineering society aes. By using the mtm physical driver configuration combined with steep crossover slopes d appolito suggested 18 decibels per octave the comb filtering or lobing is minimized. The mid center to center spacing should probably be no more than 3. D, whose name is synonymous with the pairedvertical array widely accepted as the ideal arrangement of dynamic. In all cases, the lowfrequency drivers are 25 mm behind the highfrequency driver, the diameters of the lowfrequency pistons are 100 mm, f c 2. Joseph dappolito now exclusively snells chief engineer. The speakers were placed such that those tweeters were spaced 89 inches. The woofer center to center spacing should be no more than 16 inches. Pseudo dappolito configuration by towering two pairs of.
A dappolito array does a crude approximation of a point source using two woofers and a tweeter. Here is your dappolito mtm center, with the eminence 8 woofers. Ultimately, accurate results from testing will lead to better designs. The final system design ive made is a soort of dappolito using the dynaudio esotec d260 filtered passively first order at 2 khz, then the midbass range is done. A close look at the drivers made by usher suggested that they were well, based. The advantage of the dappolito array is that it reduces reflections off the ceiling and the floor. In general, try to keep speaker driver center to center spacing no more than a wavelength distance of the highest significant overlapping frequency away from the next driver. Reversed dappolito crossover calculator lautsprechershop. A dappolito transmission line one of the most important speaker building projects published by audioxpress, thor was designed by joseph joe d appolito, who is worldrenowned for his pioneering work on mtmbased midtweetermid loudspeaker configurations. In his aes paper, he explains mathematically how an mtmconfiguration can prevent lobing errors in the crossover region, even if there is a phase shift between the two sides of the crossover. This makes the elegance g120 speaker the ideal compromise between its two siblings from the g speaker series column and prestige.
Ultrawide, detailed stereo soundstage the eris e66 delivers an expanded and highly accurate frequency response and the widest stereo field available in its class. D, whose name is synonymous with the pairedvertical array widely accepted as the ideal arrangement of dynamic transducers, is now. As snells chief engineer, dappolito will now direct all new product development. The series 5 mtm which uses seas drivers in dappolito configuration looks interesting, though it may not have built cabinets available yet. Wellrespected speaker scientist joe dappolito is the main force behind orca design which designs and distributes focal, raven, cabasse and other high end drivers, components and speakers in america. This soontobeclassic clearly explains the proper way to acoustically test and measure a loudspeaker. In this webinar we will highlight some of the most important ones. A geometric approach to eliminating lobing error in multiway loudspeakers 2000 f2 joseph a. With respect to these reference points, all three drivers have nearly equal. With this exceptional design for some exceptional drivers by an exceptional designer, transmissionline ownership is well within your grasp. Joseph dappolito onboard at snell by tom andry july 31, 2008. A loudspeaker configuration developed by and named for joe d appolito, in which a high frequency driver, or tweeter, is positioned between two midrange or low frequency drivers that each cover the same frequency range. I think there are some problems with the dappolito array, but theres a nice alternative that nobody uses.
Dappolito arrangement this loudspeaker arrangement involves placing the medium range speaker and woofer vertically above and below the tweeter with equal spacing. Depending on the exact implementation the speakers can be positioned with a vertical andor horizontal orientation. The dappolito design at audio video design youtube. The west seneca central school district is committed to ensuring that all materials on our website are accessible to all users. The cabinet is a bass reflex design with the vent placed in the rear. Regional sleeper cab driver positions available in calgary and edmonton. Two midrange for the low frequencies and a tweeter for the higher frequencies, with. Snell acoustics, a leading manufacturer of highperformance loudspeakers for more than 30 years, today announced that legendary audio designer joseph dappolito, ph. Measuring loudspeaker lowfrequency response by joe dappolito introduction. Mtm driver spacing techtalk speaker building, audio.
As a result of the phase displacement and the related interference effects, the portions of the sound emitted upwards and downwards are minimised. Joe dappolito was certainly the first to describe in engineering terms what the advantages of an mtmsetup are. Kharmas 350k, sevendriver, fourway, dappolito enigma veyron. By measuring the distance from the mike to the driver, the point is then determined relative to the driver. In either case the two midrange drivers serve a couple of purposes. The dappolito design, more commonly referred to as mtm configuration in the. It sounds smooth and sweet with a nice wide sound stage but the sweet spot is a little narrow. The midwoofertweetermidwoofer loudspeaker configuration called mtm, for short was a design arrangement from the late 1960s that suffered from serious lobing issues that prevented its popularity until it was perfected by joseph dappolito as a way of correcting the inherent lobe tilting of a typical midtweeter mt configuration, at the crossover frequency, unless timealigned. The center to center spacing of the woofers will create a forward lobe, reducing reflections off the floor and ceiling. Id never measured the performance of a cassette deckor for that matter, any type of tape deckbefore. Mtm driver spacing that rule of thumb is intended for any drivers producing similar frequencies at similar levels, such as a woofer and a tweeter at the crossover frequency or a woofer and a woofer in an mtm over all frequencies up to the crossover point.
Parts express is proud to introduce the prototype of this latest collaboration between dr. Mileage and hourly pay, work area includes alberta, western canada and usa optional. The snell illusion loudspeaker is an example of this. The sound is so blended, you cant hear the individual drivers. While it is not possible to strictly meet the new objective using 110 mm drivers, improvements in vertical radiation will nonetheless result if the interdriver spacing is. Measuring loudspeaker lowfrequency response by joe. Two separate sources spaced sufficiently apart, playing the same signals at the same frequencies will cause a ripply response due to comb filtering. The mtm configuration is often used with low frequency drivers woofers that are not similarly configured. Joe dappolito of mcintosh labs and john mickelson of audio video design discuss the look of the speakers in a room and how to balance art and technology. You might want to pm scrappydue and ask his opinion on this as i believe he owns one.
Dappolito designs tend to interact with the ceiling and floor alot less than the conventional tweeter over midwoofer design. He also pioneered the extremely popular dappolito woofertweeterwoofer driver configuration, seen in many successful loudspeakers systems. A loudspeaker configuration developed by and named for joe dappolito, in which a high frequency driver, or tweeter, is positioned between two midrange or low frequency drivers that each cover the same frequency range. For closedbox or ported systems with finite baffles this limit may be slightly lower. The spacing of the drivers must be set according to the xover frequency and viceversa, using the formula speedofsound xoverfreq centertocenter spacing.
Eris e66 active mtm series nearfield monitor with dual 6. The proven dappolito chassis alignment with a highclass softdome tweeter and two bassmidrange chassis for good music and voice reproduction is supported by two additional woofer chassis. If you have been designing and building loudspeakers for more than seventeen years, then by now you would probably have rather a lot of pieces of mdf left over. If any person with a disability encounters any barriers, or is otherwise unable to access information provided on the districts website or in any webbased resource, she is encouraged to contact the district through the department of information technology by phone. This k it uses tw o w18e001 woofers and a single t25cf002 millennium tweeter mounted in a dappolito configuration. If you go back to joe dappolitos 1983 audio engineering society paper, he discusses and analyses the characteristics of a few very specific arrangements of driver spacing, crossover frequency and crossover filter slopes, and i think that has led some to believe that an mtm speaker is only truly a dappolito speaker if it incorporates. The midwoofertweetermidwoofer loudspeaker configuration was a design arrangement from the late 1960s that suffered from serious lobing issues that prevented its popularity until it was perfected by joseph dappolito as a way of correcting the inherent lobe tilting of a typical midtweeter configuration, at the crossover frequency, unless timealigned. In the mtm arrangement the loudspeaker uses three drivers. This is more of a general question with regards to what driver arrangement allows for an easiertoshare sweetspot for either multiple listeners or for just walking around the house while listening to music on your twochannel stereo. Building on the foundation of this new driver line joe dappolito of audio and acoustics, ltd. Before i purchased them, i looked into the rs4s which had the same type of drivers, only instead of a tweeter sandwiched between two midrange drivers, it had one tweeter mounted above one midrange.
Snell acoustics today announced that legendary audio designer joseph dappolito, ph. So i was especially excited when the folks at audiomatica asked me to beta test their latest creation, clio pocket. In the above table, d is the vertical interdriver spacing in millimeters, h l is the lowpass transfer function, h h is the highpass transfer function, and a is the crossover spreading factor w nl 2pif c a and w nh 2pif c a. This is a similar design with the eminence 10 woofs btw i have a pair of diy 2way which use the eminence 10a. For all practical purposes, it is as if the drivers were operating in free space, but as a. From the rear cover to the initial onset a page in, testing loudspeakers takes a somewhat unexpected stance by trumpeting mr. Now, with a vertical dappolito arrangement you can sorta cheat this and actually use these distances per side so woofermid and midtweet spacing should be 16. For them to be free of any type of problems, the two drivers that are doing the same job, have to be 100% ts matched and work in absolute unison to be effective in producing those midrange frequencies as good as one driver can do.
Every opportunity has been taken to inundate the reader such that heshe will not soon forget the author has a ph. Jamo 626k4 3way mtm dappolito high performance kevlar. Infinty crescendo 3008s inverted on top of infinity crescendo 3009s. For a given driver, bass response will extend well below that produced with either a vented or sealed enclosure using the same driver. The reference point location for a flat phase pattern is shown for each of the three drivers as the red circles in the illustration on timealignment 5. If you dont adhere to that design principal, then its just a tweeter mounted between to woofers. This compact tweeter permits closer than normal spacing of the midbass drivers resulting in a near ideal vertical polar response pattern for home theater. Speaker project usher ua711 and ua721 speaker systems. Any difference in sound by putting speaker vertical or horizontal. There are certain dispersion advantages with a dappolito design that a conventional design does not share. Thanks all for the great discussion on the dappolito configuration. There is a question to be asked with dappolito speakers, that have the critical midrange handled by two drivers. However, the 626k does not have just a ordinary 3way design, but a unique mtm midwoofertweetermidwoofer dappolito arrangement with dual woofers surrounding a rotatable tweetermidrange baffle module which maximises dispersion angle consistency in both vertical and horizontal orientations. Flat deck drivers company driver positions available for.
The midwoofertweetermidwoofer loudspeaker configuration called mtm, for short was a design arrangement from the late 1960s that suffered from serious lobing issues that prevented its popularity until it was perfected by joseph d appolito as a way of correcting the inherent lobe. The tweeters low 600hz resonance gave dappolito confidence that it could be smoothly crossed over to the midrange driver at 2. Dappolito on what matters audiogon discussion forum. Hi, i fear this can potentially seem powerfully ridiculous, but i have that idea for some time now. This only occurs when the driver spacing much shorter than the wavelength of the. Surely there must be some good reasons for not going with such a design, such as axioms m22ti speaker.
Take two pairs of the same speakers, and put one pair on top of the other, upside down, to achieve more or less a dappolito configuration. We will describe how serialization is normally handled, and how you can customize the process when you need to, including some tips on migration strategies when your class definitions change. Audiogon the worlds largest highend audio community. Advantagesdisadvantages of dappolito audioholics home. Joseph dappolito, contributing editor for speaker builder magazine. Its nested midwoofertweetermidwoofer mtm, also known as dappolito configuration offers improved offaxis. This is the oe speaker in the drivers door of a mini cooper with the microphone in the drivers seat. The proteus to d appolito or not to d appolito, that is the question. Dappolito spacing techtalk speaker building, audio. The left and right channel speakers use the mtm geometry the d appolito configuration with a pair of 6. Our newly developed line of lowercost fully shielded drivers forms the basis for the designer series of home theater loudspeaker system. Usher ua711 and ua721 speaker systems make it bigger and smaller at the same time, make it more versatile, and of course, make it sound amazing. The measurement techniques contained in this book provide all clues you need to refine your speakers components to improve its.