Classic 6-Transistor circuit (many variations of this where around in the 1960`s & 70`s), NPN only output devices, fairly high level of Bias, single rail, input and output coupled via a capacitors (electrolytics - no less), clever feedback loop, bootstrapped load for the second stage, both voltage amp stages using some local degeneration too.
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I fixed so many of these, I could nearly draw out a circuit diagram from (> 15 Years old) memory. Nothing too unusual, it just sounded very good. Combined with an passive EQ circuit and a KSP215 8" Full Range driver these drove for example east german Radio/TV Monitors and these things where darn good. The later generation of Amplifiers in East Germany has the standard circuit (read Self if you want to know what i call standard) and DC coupled outputs etc. And they measured a lot better, had more power and all, but sonically they had a "typhical transistor sound" (in the negative sense), which the old outdated designs lacked and in a Studio where you can directly leave the studio and walk up to Mikes any significant deviation from subjective neutrality is easily heard. Too much generica out there that sounds in the main negative attributes as bad as the next (which is not to say all these amplifiers sound the same, they merely sound equally iriitating in different ways). Given that making an amplifier with low THD does not garantee that the resulting amplifier will sound better, more realistic, less coloured; whatever term you wish to use; than one with higher THD, what reason exist that could make any SENSIBLE person bother about THD as anything but an academic excercise Of course there are people who slink off with the spec sheet of their amp to the gents, oooohhh, the low THD, ahhhh the high power and all that, but if it...
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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