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.
Both boards will be wired in parallel mode, and then the input to one of them will be inverted for more power. The sound is excellent, by far the best I’ve heard from a chip amp. This projects have the Frequency response and the total harmonic distortion: Separate position attenuators for each channel. Figure 5 the components layout. 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.
Construction Notes Introduction The model Gaincard from 47 Laboratories is a 25 Watt stereo amplifier about the size of a video cassette, powered by a large external supply.
I conclude from my experiences that carbon film is the right choice for the R2-R4, AB carbon composition sounded too noisy and fuzzy, metal oxide too grainy, and from a different circuit metal film too, uh, metallic and zingy. It is also possible to use a transformer with a center-tapped secondary winding.
Parallel mode allows the amp module to drive a 4-ohm load at W. The case is not the nicest I just found it sitting around but it works fine and it looks a lot better in real life. LevHyp 19 May Reply.
From stereophile Z in data. The only donwnside is it is only capable of driving an 8-ohm speaker.
LM3875 Gain Clone Amplifier Project
The signal into the ultra sonic filter l3m875, which include of capacitor C3 and resistor R3 and R1 To act to prevent the radio noise signal and attenuate RF signal is lower, before the signal will into pin 7 thus this have high gain up to 25 times. This gives the stated nine part circuit. This is gainclone amplifier ;cb that sound quality is very good. 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.
Separate power supplies can be used for each channel if desired.
Figure 4 the PCB layout. The transformers hummed and so did the ;cb outputs. An extremely low parts count also allowed for a very compact and pb design, as evidenced by numerous websites, fora and blogs dedicated to audio DIY and Gaincard clones aptly named ‘gainclones’ or ‘chipamps’. The following is a suggested layout-schematic for the power supply: The brown lines are jumpers that need to be wired into the circuit.
LM Gainclone Amplifier Indroduction: The input impedance of the amplifier is determined by resistor R1.
Power supply parts list: Top Background Information Some things we know for sure: 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. R4 is soldered directly between the leads of the IC, which is itself tucked underneath the board together with R2 and R5. So it is almost a complete IC without additional circuitry, thus leading to yet more user-friendly and convenient.
All the capacitors and R3 are on the top side. If your speakers are 8-ohm, you only need one pcb for both speakers, with a power output of 50W per speaker. The RCA input ground can go to the base of the attenuator, rather than R2.
This resistor can also be omitted in most cases, which is best determined experimentally.
There are no dedicated heat sinks here because the entire aluminium chassis, which houses the amplifier, serves as a heat sink Figure 7. Can be up-graded into a pair of complete mono amplifiers by adding another Model Power Humpty. Figure 3 the schematic diagram. I lm33875 both Shottky and ultrafast types, rated 3 or 5 amps.
This article focuses on a tried and true low-power amplifier 30W with the IC LM, originally intended for the design and testing of active speaker systems.