Way Crossover Design Software' title='3 Way Crossover Design Software' />Myths Facts about Loudspeaker Crossovers Identifying Legitimately High Fidelity Designs. This article explores some of the myths and facts about crossover. It also discusses some of the mistakes often made by loudspeaker. It is our. hope that the reader will gain a better understanding of the mechanics of. The loudspeaker crossover can be considered the. It directs the. bandwidth of frequencies each driver is optimized to reproduce while it also. Without the. loudspeaker crossover, a loudspeaker driver such as a tweeter can be overdriven. L2j Server H5. A loudspeaker system without a properly. Properly designing a loudspeaker crossover requires. There are often times manufacturers. Let us briefly define some basic crossover. A High Pass Filter HPF bandwidth limits. Cracked Font Helvetica Neue there. A Low Pass Filter LPF bandwidth limits. Traditional filter theory deals with 3d. B points where power is cut in half. However, since we are dealing with actual sound pressure SPL and not sound power, loudspeaker engineers typically deal with 6d. Way Crossover Design Software' title='3 Way Crossover Design Software' />B points when working with crossover networks. Think of a tweeter trying to produce bass. It cant do so efficiently. HPF to block those frequencies. Conversely think of a woofer trying to. We employ. a LPF to effectively filter the frequencies above which the woofer is capable of. Loudspeaker is a very important component of a hifi system. By adding a crossover network to the system of speakers, the low, high and midrange frequencies can. From the Honda CRV and the Toyota RAV4 to the Subaru Forester, Hyundai Tucson, Ford Escape, and Mazda CX5, check out this Big Test comparison right here. The diagram pictured here. The squiggly looking. This diagram is courtesy of. Williamson labs. For more information on this topic, we recommend. Filter Crossover Types for Loudspeakers. Myth 1 The Simpler. Crossover is ALWAYS Better. Weve. seen numerous loudspeaker companies defend their 2 or 3 element crossover ie. Resistorcapacitor network only as being preferred to a more complex crossover. They argue that they custom designed their. Tabulated. below is a list of filter slopes based on order for the readers reference First order 6 d. BOct. Second order 1. BOct. Third order 1. BOct. Fourth order 2. BOct. The. reality here is sometimes the exact opposite. A two or three element crossover on a two way bookshelf speaker. Unless the driver has been. This is especially true with stiff cone. Higher order networks are typically needed. Having no network at all. NOT a viable solution if high fidelity reproduction is the primary goal of. First order. filters arent good at preventing distortion, particularly at or below the. They also. dont provide enough isolation of the bandwidths in multi driver systems. The. result is too much of an opportunity for destructive interference, and. Its important to note that a tweeter still remains pistonic above and. Fc while a woofer does not. This is why second order or higher filter. The bigger parts are more. This requires a tighter set of. Editorial Note About Directivity, Crossover Points Driver Selection by Dr. Floyd Toole. A good sounding loudspeaker needs to have smooth. We describe this in terms of directivity as a function of. In deciding on the drivers to be used in a speaker system it. This means that when the acoustic. It is not sufficient. So, in addition to. The most difficult transitions occur when the transducers. Editorial. Note by Steve Feinstein on Crossover Frequency Selection. A basic, ages old but still true, rule of. If a tweeter has an Fs of 1. Hz, use a 3. 00. 0 Hz. If a midrange is 3. Hz, use 6. 00 Hz. Another good rule of thumb says, 1. B down. at resonance. If a tweeters resonance is 1. Hz, the voltage curve of the. B from 0 d. B. That. This was the rule at a major speaker. I used to work at, and the engineers all hated it, because it was so. But we almost. never lost a tweeter and our warranty costs were vanishingly low. Real world. properly designed filter network will always present a stable load impedance to. It will also properly bandwidth limit the loudspeaker drivers to. The power response is simply the total. This. is discussed in greater detail later in the article. Compromising. a crossover design results in MORE losses and MORE distortion than a properly. This is especially true when the compromise is poor parts. The. most obvious visual cue is simply size. A small cheap crossover is just that. Small and cheap.     Poorly. The crossover above left pic is from a two way bookshelf speaker system we have previously reviewed. The speaker system employs a stiff cone driver which. LPF to limit its bandwidth to reduce its. The manufacturer chose to use an electrolytic capacitor as a measure of cost savings at the expense of performance as these parts have higher resistance and performance variances. This is bottom of the barrel. At low power levels these speakers dont sound bad but once the volume is cranked up, audible driver break up was identified by our panel of listeners in blind comparisons. The. crossover image right above pic is of a much higher caliber design by an. Instead, the engineer understands the importance of proper crossover. The designer invested an appropriate portion. Notice how air core inductors are used in critical circuit paths and. The. tweeter circuit runs vertically up the left side of the photo. The woofer. circuit is on the right. You can see how the inductors are located in the. Tweeterwoofer nearby inductors are oriented at dual right angles with each. There literally is more woofertweeter crosstalk from. Interestingly. the philosophy can be continued that its better to run a midrange driver full range. HPF element at all because it contributes to the overall bass output of. While there is some validity to this approach, care must be taken so that the actual driver can handle the stresses of being run full range. It is noteworthy to mention a. Hz or so.   Any additional bass output the midrange may be. At the same time, not crossing over the midrange driver essentially. HPF.   It can be argued that this wastes amplifier power and increases the. A loudspeaker designed like this when turned up in volume has the potential to experience audible break up from the midrange driver. This is especially true as it exceeds its excursion limits because of a lack of protection at high. There are always exceptions to this, that hopefully a loudspeaker designer considers when choosing not to employ a HPF network on a dedicated midrange driver. We. rounded up several tower speakers a couple of years ago and found both trained. In our option, a simple fix to their crossover. HPF would have greatly improved the sound quality of this. It just needed a crossover fix that wasnt. The speaker itself still scored very highly in our listening tests but we as Audioholics are always picking nits with all products we review to keep pushing manufacturers into making better next generation products that we can all salivate and eventually upgrade to. Editorial Note about Running a Midrange Driver with No HPF. Paul Apollonio. By eliminating the series high pass capacitor at the. VERY minimum needed to protect the midrange driver from dangerous levels of. NOTHING to the output of the. Woofers hence lowering system sensitivity. The low frequency. A sinewave sweep test  to measure this problem will be unrevealing in. To see this problem, one must. One can see distortion products as sum and difference frequencies. This is a simple process and one all audio engineers are familiar with. Even if the Midrange driver is made INCREDIBLY stiff, and placed in a very very. There is such a thing as recommended practice and procedures, and the practice. NOT a good idea by any stretch of imagination. Allowing the large peak amplitudes of low. Car Audio CROSSOVERS The Basics of Two Way Passive Crossovers This is great if you are using a speaker with ferro fluid a magnetic fluid in the voice coil gap which modifies the impedance to a relatively flat value. So before you calculate a passive crossover network, you must first correct the inherent impedance problems.