The Gainclone. Introduction: Background Info: Construction Notes. Introduction. The model Gaincard from 47 Laboratories is a 25 Watt stereo amplifier. Check for Samples: LM The LM is a high-performance audio power LM to reduce the effects of PCB trace resistance and inductance. PCB for 56W Audio Amplifier using LM HiFi Amp. For LM IC. High quality FR4 double-sided, plated-thru and tinned holes, with conformal coating.
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POWER AMPLIFIER WITH IC LM3875
Carbon resistors are used throughout. LevHyp 19 May Reply. Power supply parts list: An example of a circuit that could do this would be using a Texas Instruments DRV chip to invert one of the two non-inverted amplifiers.
The next build used the LM chip. Increasing power output into an 8-ohm speaker is trickier. I prefer two bridge rectifiers, but one bridge or 4 individual soft recovery diodes can be substituted. However, if your amplifier has a volume control potentiometer, as this one does, the resistor can be omitted. Rigid and compact aluminum chassis construction to release vibrations smoothly.
Also, the concept is so minimalist that it leaves very little room for major mistakes so you should be able to freely indulge in fearless experimentation with different values and brands of capacitors, resistors, etc. How to builds This projects is easy to builds because to adjust anything and few parts as Figure 4 and Figure 5.
You may not upload this material to any public server, on-line service, network or bulletin board without the prior written permission of the author. As a result, you will need to use four amplifiers two boards per speaker and a circuit capable of inverting the signal to one of the amplifier pairs. I also compared it with a W x 6 home theater amp, and the home theater amp in stereo modewas able to reach higher volume without distortion, but they were very close in sound quality. For a given capacitance, a lower voltage power supply gives a softer, more relaxed sound.
You can use a linear power supply to take at next level this circuit. Learn how your comment data is processed. Is used as a supply voltage to the IC power supply or amplifier circuit. I can’t comment on sound quality in parallel mode, because I only wanted to use that mode to try and run a 4 ohm subwoofer speaker. The input impedance of the amplifier is determined by resistor R1.
I compared a few different amps. The amplifier can be used in the inverting mode, as well. Figure 1 The pins using of LM After comparing a 4.
Gainclone amplifier circuit,stereo 40W using LM
I conclude from my ln3875 that carbon film is the right choice for the R2-R4, AB carbon composition sounded too noisy and l,3875, metal oxide too grainy, and from a different circuit metal film too, uh, metallic and zingy. Resistor R4 at the output of the amplifier improves stability and, in parallel circuits, helps to split the load between two amplifiers. This page dates back to the beginning when the Gaincard was literally a black box.
C1 should be included to protect your speakers but can be omitted if you know your source components are not DC coupled at the output. I tried both Shottky and ultrafast types, rated 3 or 5 amps.
Note that C1 must be non-polar. To bypass the capacitors, just run a jumper for each of them. All the unused pins are cut off except for pin 11 which is kept for mechanical stability. Separate position attenuators for each channel. The total cost of the project is a mere odd EUR so heck, why not?
Both the amplifier and external power supply were cased in Hammond series cast aluminum boxes. If you are planning on driving 4-ohm speakers, use one board per speaker, with the positive outputs wired together. You wire the two boards using the parallel mode schematic. We use a IC as main parts is. This chip delivers unbelievable quality, especially for it’s low power levels.
This result is shown below: If you do it right the amplifier is completely quiet but grounding can be a problem. Figure 1 The amplifier schematic is shown in Figure 1. In the years since this started, power lm8375 have become a major part of the DIY scene with dozens of different circuits and hundreds if not thousands of builders worldwide.
This is lm8375 amplifier circuit that sound quality is very good. Attenuator is ladder type. To connect the output of the amplifier to the speaker output terminals, a thicker solid or stranded wire should be used while high-quality shielded cables should be used for input signal wiring.
Capacitors C1 to C4 are used for the filtration of the ripple voltage from the rectifier.
The RCA input ground can go to the base of the attenuator, rather than R2. I also have pretty much the same short length of signal path and feedback loop, the latter obtained by soldering R4 directly across the chip leads. However, if you decide that you wish to squeeze pb power from the amplifier, you will surely need better cooling.
If ran at a low voltage, it will be able to drive a 4-ohm load, though not well. Four FE5D diodes are used for rectification. Photos of my amp: Power cord is captive four pin molex, one per channel. It is reccomended to use a. The output signal must not share any of the inverting input ground path.