A simple 3-way crossover, intended for triamping Hi-Fi systems. This is a conventional 12dB / Octave unit, and cannot be expected to have the same performance as a Linkwitz-Riley aligned filter network. It will still be a vast improvement over nearly any passive crossover, and is ideal for beginners or those who want to experiment further with multi-amping, but without the complexity of a major project. The retuning (to (sub)-Bessel / Linkwitz-Riley alignment) is recommended, as the performance will be more in line with modern standards - see information below.
Click here to download the full size of the above Circuit.
The crossover is based on the 2nd order Butterworth filters. The resistors Ra and Rf set the gain of each filter to 1.582, which is slightly less than the required value of 1.586. This value of gain (Ao) follows from the formula ...
k = 3 - Ao where k = 1 / (Q-factor of the filter).
For a 2nd order filter, the value of k can be obtained from the butterworth circle for n = 2. It turns out that k = 1 / cos(x), where x = ? / (2 * n) which is ? / 4 in this case. Thus for a butterworth response, the Q-factor turns out to be 0.707. Please see references (1) for more details.
Note that the mid-range filter is preceded by an inverting amplifier. This is needed for 2 reasons - Firstly, the gain of the mid-range is (1.582 * 1.582) which must be brought back to the level of the low-mid & mid-high ranges (1.582). Secondly (and more importantly), the 2nd order butterworth filter has an inherent property of shifting the phase of any signal passing through it depending on the signal's frequency so that at cut-off the signal is 90° out of phase with the input (direction of shift depends on whether the filter is high-pass or low-pass).
Thus at 300 Hz the low-mid range filter has shifted the signal by 90° and the mid range has also done the same (but in an opposite direction). Hence, at 300 Hz, the signals appearing at the low-mid range & mid range outputs are going to be 180° out of phase with each other & will cancel out...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
characters left: