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.

Author: Arara Nehn
Country: Andorra
Language: English (Spanish)
Genre: Photos
Published (Last): 27 February 2014
Pages: 500
PDF File Size: 14.98 Mb
ePub File Size: 13.49 Mb
ISBN: 273-8-76002-825-9
Downloads: 74170
Price: Free* [*Free Regsitration Required]
Uploader: Akisida

I tried replacing pbc two 50A bridge rectifiers with 4 discrete diodes. And its its an easy and safe project to build. The RCA input ground can go to the base of the attenuator, rather than R2. All the capacitors and R3 are on the top side. From stereophile Z in data. Can be up-graded into a pair of complete mono amplifiers by adding another Model Power Humpty. Is used as a supply voltage to the IC power supply or amplifier circuit.

The Gainclone

An extremely low parts count also allowed for a very compact and customizable design, as evidenced by numerous websites, fora and blogs dedicated to audio DIY and Gaincard clones aptly named ‘gainclones’ or ‘chipamps’. In short, no excuses. Figure 1 The amplifier schematic is shown in Figure 1.

In general, though, the capacitors affected the sound lm38755 than the resistors, the diodes more than the capacitors, and the transformer most of all.

Also, the concept is so minimalist that it leaves very little room for major mistakes so you should lm38775 able to freely indulge in fearless experimentation with different values and brands of capacitors, resistors, etc. This circuit is very km3875 for a small hifi system in house, with medium overall specifications. It amplifier uses a power op-amp and a minimum of parts, connected with the pcbb possible signal path, particularly the feedback loop.


In Figure 3 This project is non inverting amplifier circuit. Increasing power output into an 8-ohm speaker is trickier. I prefer two bridge rectifiers, but one bridge or 4 individual ppcb recovery diodes can be substituted. LM product folder and LM I recommend a binary star ground as follows: Currently, I’m not done with the circuit or board for that yet.

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. This chip delivers unbelievable quality, especially for it’s low power levels.

Figure 4 the PCB layout. 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. The wiring is done like this: For a given capacitance, a lower voltage power supply gives a softer, more relaxed sound.

The power supply is very simple. I tried both Shottky and ultrafast types, rated 3 or 5 amps.

Rigid and compact aluminum chassis construction to release vibrations smoothly. The sound is excellent, by far the best I’ve heard from a chip amp. We use a IC as main parts is. The next build used the LM chip. This reduces the risk of DC offset voltage appearing at the output of the amplifier, which may have an adverse affect on the operation of the speakers, as well as the amplifier. It is also possible to use a transformer with a center-tapped secondary winding.

This schematic is for half of the board only.

ln3875 The DRV inverts and balances the signal so that one of two non-inverted amplifiers amplifiy an inverted signal, thus allowing bridge mode to work. However, if your amplifier has a volume control potentiometer, as this pfb does, the resistor can be omitted. This amplifier is compact, looks great, sounds great, has a few dozen clean watts per channel, and dissipates only 2.

This result is shown below: The volume potentiometer can be implemented as a standard potentiometer or, as in this case, stepped attenuator.


The left-channel audio signal is connected to the input, to resistor R2 act as set the impedance of circuit is 33K through the coupling capacitor C2. The brown lines are jumpers that need to be wired into the circuit.

Gainclone LM3875 PCB

The input impedance of the amplifier is determined by resistor R1. Attach all the S grounds together, and all the P grounds together, and then connect the two grounds by a single wire. Soft recovery types are probably the best bet. Given that this is a l3875 simple and newbie-friendly amplifier, which has been successfully built many, many times with identical or very similar results, your satisfaction with the project should be guaranteed.

However, if you decide that you wish to squeeze more power from the amplifier, you will surely need better cooling. 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.

Gainclone LM PCB – Electronics Projects Circuits

See below for how to wire this circuit into parallel mode. This site uses Akismet to reduce spam. An example of a circuit pccb could do this would be using a Texas Instruments DRV chip to invert one of the two non-inverted amplifiers. The case can be left floating or attached to the signal ground.

The board also has a spot for a 22uf non polarized capacitor between R4 and ground. The actual layout of the circuit board could be something like this: Note that C1 must be non-polar.