I have heard people say that it is very difficult and time consuming to design a successful. It has been, and still is, my belief that it is difficult and expensive to do subwoofers right. Transmission line speakers take the principle of matching a speaker driver to the correct amount of air pressure behind the cone in this case the volumetric capacity of a shaped chamber or pipe, to help sort out resonance problems and enhance certain frequencies. Transmission line loudspeakers have long enjoyed a small, but dedicated following. King, mass loaded transmission line mltl speakers are now relatively straightforword to design for the diy audio enthusiast. Krueger audio s310 2 way mtm transmission line hybrid loudspeaker. Martin has made his software for tl design freely available and anyone serious about designing and building a. Like the bassreflex, the transmission line damps out the resonant motion of the cone, but it does it with a lower q, or sharpness, so that you tend to get a single bump instead of the double bump of figure 1. The original thor transmissionline design was published in may 2002 and joe himself wrote about the project.
Fundamentals of transmission line design euci course in. The dayton audio mk442t transmission line tower speaker raises the bar in the budget speaker arena. Transmission line speaker build i like the look and relative simplicity of transmission line speakers in that they generally have a longtall cabinet with a single driver no crossovers. New, free transmission line modeling software techtalk. Spiffy one way full range transmission lines i find crossoverless speakers quite beguiling. Its amazing how good a simple, cheap, oneway driver can sound in the right enclosure, like a voigt pipe or a transmission line. This system features a morel mw266 woofer in lightly stuffed tl tuned to 27 hz and a morel cat378 tweeter. The bottom line, are transmission line speakers efficient yes, are they hard to build yes, and i would recommend them to anyone who has the time and the skills to make them. Recommended audio software simulation and modelling tools, hornresp, mjk mathcad, winisd, pcd, xlbaffle, the edge, and more. Basically, an mltl is a quarterwave transmission line enclosure with a port. Derivation and correlation of a general acoustic model for a fiber filled transmission line loudspeaker.
Updated specs for all line types to match current data from manufacturers web sites as of late 2010. The leonard audio web site and software appears to be available in the web. Clear and accurate bass reproduction and minimum diffraction time aligned design. If you do not have access to mathcad, mathsoft makes a mathcad viewer available, which allows you to work with the programs and perform all the needed simulations. Information on transmission line design for diy and other audio related information including filter design and bafflestep information transmission line speakers a gathering of. Discuss the basic concepts of transmission structure foundation design. Dayton audio mk442t 4 2way transmission line tower speaker pair. A transmission line loudspeaker is a loudspeaker enclosure design which uses the topology of an acoustic transmission line within the cabinet, compared to the simpler enclosures used by sealed or ported designs. A transmission line speaker with the design work to back it up. They utilize a tapered transmission line but at a much lower ratio, something more like 1. Figure 3 shows the impedance of a woofer in free air and in a transmission line tube tuned to the resonant frequency. New, free transmission line modeling software just tried it briefly, and its pretty cool. Quickfield packages that can be applied to the various aspects of transmission line design. There is a lot of information about transmission line speakers available on the internet, but unfortunately a lot of that information is either based on classical transmission line design which is basically obsolete, andor is just flat out inaccurate.
Our largest and most powerful eikona loudspeaker to date. Apr 03, 2018 there is always a first for everything, and this is my first transmission line tl speaker build. The thor is the topofthe line loudspeaker kit from seas. Compact transmission line loudspeaker system gallery. The most common example of a loudspeaker that relies on a quarter wavelength acoustic standing wave is a transmission line enclosure. Transmission line modelling software page 85 diyaudio. Thanks to a collection of mathcad programs developed by martin j. When the transmission line speakers system impedance curve is split into the driver impedance and the transmission line impedance, as shown in figure 6, it becomes obvious that the adjustable variables relate to the first minimum in the.
Transient magnetics switching on and shutting down analysis. It was a small room, about by 17, totally untreated, without a lot of speakers on display. Calculate and display distributed rlgc transmission line parameters. A transmission line enclosure is a waveguide in which the structure shifts the phase of the drivers rear output by at least 90, thereby reinforcing the frequencies.
New, free transmission line modeling software techtalk speaker. Peters loudspeaker designs northwestern university. Calculation of line parameters with nonsinusoidal currents. Transmission line calculator hifi loudspeaker design.
I have built several speakers over the years and i would like to do something a little different. We designed the crossover for this one and paul did the rest. Perceval while i think youre right about the measurement set up as shown being problematic, what id be far more concerned about is the crazy almost 30db spike centering at 200hz which is almost exactly the wavelength of the 1. The software itself is worth that much if you require such calculations.
Dec 05, 1978 the first of these speakers, a bassmid range unit is acoustically coupled to one end of the fiberfilled transmission line by exposing the speaker radiator rear surface to the line while the second speaker, a high frequency unit is acoustically isolated from the line by encapsulating the speaker radiator rear surface in a housing integral with. A transmission line loudspeaker is a loudspeaker enclosure design topology that uses an acoustic transmission line within the cabinet, compared to the simpler enclosures used by sealed closed or ported bass reflex designs. It can model ported mltl and transmission line with what looks like infinitely variable control over geometry, and placement and amount of stuffing. Software tools spice, pcb cad, speaker design and measurement. Dual fold onaxis transmission line enclosure calculator db. Quarterwave transmission line speakers employ enclosures that are tuned to provide lowfrequency extension for the speaker driver. The source of pmcs legendary natural, realistic sound is the advanced transmission line atl bassloading technology, professionally proven all around the world.
Paul kittinger has worked with philharmonic audio and salk sound on their mltl transmission line designs. They are essentially nonresonant enclosures, producing a deep, wellcontrolled bass response. Instead of reverberating in a fairly simple damped enclosure, sound from the back of the bass speaker is directed. Please let me know what it sounds like if you build it. There is always a first for everything, and this is my first transmission line tl speaker build. Transmission line speaker box math made easy youtube. The design goal was to get below 60 hz response from a. Transmission line, ported and vented designs are three different concepts on how to load the bass driver in a speaker enclosure.
Transmission line speaker calculation perry marshall. Examine and identify all parts, pieces, hardware, etc. The thor is the topoftheline loudspeaker kit from seas. Who makes a true transmission line speaker audiogon. There are several types of transmission line enclosures and one of the more popular ones is the mass loaded transmission line mltl. Martin j king for dummiesan introduction to using the mjk quarterwave simulation software. A transmission line speaker with the design work to back it. For a long time i had been resistant to the idea of using subwoofers. The formulas used in the calculator create a design that suggests the most maximally flat response in an anechoic environment based on the number of drivers, the thiele small parameters and the allotted dimensions specified in the users input fields.
This project is a small tapered transmission line speaker design for use as desktop or small room speakers. Ive done some reading on the subject, and the general consensus is that nobody really knows a triedandtrue method to mathematically solve the problem. They have a couple of nicks on the edge where a small sliver or two of veneer is missing, but nothing that is easily seen except under close inspection. The enclosure uses a transmission line configuration, derived both from sophisticated computer modeling and extensive experimentation. Technically it is the acoustic analog of the electrical transmission line, typically conceived as a rigidwalled duct or tube, that is long and thin relative to the wavelength of sound. Designing massloaded transmission line mltl speakers. It is a full range, floorstanding system that provides the very highest level of acoustic performance.
Atl uses energy generated by the bass unit in a much more intelligent, efficient way than speaker designs based on ported or sealed boxes. Transmission line program for windows tlw 2014 update rf cafe. Mathematics of the transmission line speaker enclosure. Transmission line speakers are similar to vented designs but having the additional attribute of the additional low end support due to the quarter wave response of the line. Modelling the transmission line as mentioned, this is my first tline, so you should look elsewhere for expert advice. Transmission line speaker build by soundblab youtube. Ill give it more time when you can enter speaker data more easily, and i can test it with known to me drivers. Imf model tls 50 ii transmission line speakers for sale us.
Transmission line loudspeakers software free download. The two w18e001 woofers excite the line at slightly different points, smoothing the response and increasing the range of bass output. Line taper survey a survey of some published tl designs and be sure to check out martin j. Classic transmission line enclosure alignment tables. Fried benchmarks include the model h system, the first modern satellitesubwoofer system, the model m 1977, the first satellite transmission line subwoofer in one unit, the super monitor which many still consider to be one of the premier speakers of our day, and the b satellite series 1976 to 1979. Transmission line loudspeaker, free transmission line loudspeaker software downloads, page 3. In a mass loaded transmission line, we actually have 3 factors governing the bass response of the speaker. How do transmissions lines differ from ported and vented. A speaker design software is a computer application that is developed to assist the designers of speakers in bringing out the best designs that will have various effects. Know the applicable codes and standards required to perform transmission line design credits. Transmission line floor stander speakers for sale or trade. Btw, i have perfected a new woodworking method to help reduce the time to make each transmission line speaker.
Acoustically, tl speakers roll off more slowly less steeply at low frequencies, and they are thought to provide better driver control than standard reflex cabinet. Essentially, the software in this category will pick all the components of the speaker being developed in terms of measurements as well as the type of materials being used. A gallery of customers who have built their own speakers from our kit designs. Instead of reverberating in a fairly simple damped enclosure, sound from the back of the bass speaker is directed into a long damped pathway within the speaker enclosure, which allows far greater control and use of speaker energy and the resulting sound. Tried cambridge r50 but not enough sub base and the sound was murky as hell. Hi moving the position of the driver down the line affects the various. Jul 23, 2016 the original thor transmissionline design was published in may 2002 and joe himself wrote about the project. Theory and projects, mostly diy speakers and subwoofers.
The transmission line produces 4 db of bass lift from 20hz to 110hz, with less than 1 db of ripple. There is a sealed box and ported design speakers and then theres a rare type we dont often hear of anymore called a transmission line. Amptools tm is trademark of altec lansing corporation calculates damping factor, powertoload, 2wire sizes, and cable losses. A transmission line loudspeaker is a loudspeaker enclosure design which uses the topology of an acoustic transmission line within the cabinet, compared to the simpler enclosures used by sealed. Ported speaker are the most common as they are cheap to build and. Transmission line modelling software page 81 diyaudio. Diy transmission line loudspeakers theory, design, and building. Let us bring your loudspeakers back to life by giving them a full mot using our repair and upgrade services.
Qts is speakers total quality in ratio to its electrical, and mechanical characteristics, qms is the mechanical ratio. Ac magnetics electromagnetic field and current distribution. I seem to be less tolerant of crummy bass than the average joe. See more ideas about speaker plans, speaker, diy speakers. Review physical transmission line design and the software used to perform analysis. Since martin kings software is no longer available is there a suitable replacement. You can simulate transmission lines, back loaded horns and ported boxes as long as the port is at the end of the line. How to build diy transmission line speakers dave cropley. Transmission line loudspeaker software free download. Dayton audio mk442t 4 2way transmission line tower.
The mk442t tower speakers take advantage of quarter wave enclosure tuning to accomplish bass extension unheard of in this price range and form factor. The line is tapered, and filled with dacron stuffing. What initially sparked my interest in tl designs was listening to pmc speakers. But, when building a tline for a sub based on fs, you need to keep in mind the speakers qts, and qms, they should be low for sq, qts of. So long ago i adopted a do it right or do without philosophy for low bass. Fullrange single drivers multi way loudspeakers, open baffle ob, infinite baffle ib, sealed, ported, vented, bandpass, transmission line tl, front and back loaded horn, tapped horn. Sound really fantastic, particularly with spikes installed included well controlled and substantial but not overwhelming bass. An acoustic transmission line is the use of a long duct, which acts as an acoustic waveguide and is used to produce or transmit sound in an undistorted manner. New, free transmission line modeling software i didnt have time tonight to make comparisons to other software but i did check the program itself for utility and features. I can state that among all the programs and data on the antenna handbook cd, i find transmission line for windows tlw to be the program that i use the most. Transmission line speakers for sale in uk view 16 ads.
This style of loudspeaker has been on the fringe of the audio mainstream for many years with just a few smaller companies building and marketing this enclosure design. Transmission line, mltl software techtalk speaker building. The reynauds i am familiar with are more line tunnels than transmission line, but i gather you have all been over these differences. The first of these speakers, a bassmid range unit is acoustically coupled to one end of the fiberfilled transmission line by exposing the speaker radiator rear surface to the line while the second speaker, a high frequency unit is acoustically isolated from the line by encapsulating the speaker radiator rear surface in a housing integral with. I havent read the entire thread, but i heard the vsa 4 juniors in the same room on the same day as the rest of paag. A transmission line speaker with the design work to back. Like a vented design, we have the parameters of the. This is a calculator for designing a dual fold onaxis transmission line enclosure. Transmission lines and sealed boxes have a 12db per octave roll off after the resonant frequency, while a vented box has a 24db per octave roll off. The transmission line is a seldomused speaker design which.