By sufficiently lowering output impedence of a circuit and supplying enough current to drive cables, it does not suffer the same problems as passive designs. As such, it seems to solve the many of the problems inherent in both active and passive preamps without causing too many additional problems of is own. The problem that I encountered in doing such a build from the Stereophile
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article is that not only is the monolithic buffer used there not readilly available, but the successor to it is also not available (they are available on the NOS market, however, if one is really interested. ) Further, of the currently available buffer chips, all of them (like the Burr Brown buf634 or the Intersil HA3-5002) seem to have something about them that make them poor choices for this type of projetct - prmarily that they just don`t sound that good. This leaves a couple of additional options: The first is to use an opamp that is stable at unity gain. Opamps, however, suffer from the same problems as existing monolithic buffers (that they sound bad). Further, the best opamps are generally not stable at unity gain anyway, and thus, this would become an active preamp. The two remaining options, however, are both good. These are to use a discrete solid state design, or to use a tube design like a cathode follower. For this project I chose to use the cathode follower. Cathode followers are much maligned, but at the same time they crop up in a lot of places. Despite the bad press, they do a good job of lowering the output impedence of a circuit, and really don`t sound as bad as their reputation suggests. As has been said elsewhere, you don`t listen to the reputation. This project is just getting started, so for now it is only a circuit, and a PCB design. When, and if, it gets built, I`ll post more. For now, here is the...
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.....
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