GC version LM1875 quad-core parallel amplifier board kit – Class A, mini Class A

The basic evaluation method of true and false LM1875:

The real LM1875 can be put on AC22VX2, and the counterfeit will fry if it exceeds 18VX2. The real output is protected, and the output short circuit will not burn, and the counterfeit output short circuit will blow up. If it is TDA2030A, it will blow up if it exceeds 16V.

The kit needs to be welded by yourself, please choose the spare parts or finished board according to your own DIY ability. The default main capacitor of the kit is the original UK NOVER 10000UF 35V, which is more durable than Nippon Chemical and Nikon.

The kit does not contain the main heat dissipation, so it needs to be purchased separately. Because the output of 8 pieces of LM1875 small armor is higher than that of a single piece, this is normal. If you require no temperature, you can buy a digital power amplifier.

GG version is the full name.Gaincard is a very sound LM1875 circuit that has been repeatedly compared and optimized abroad. It has frequency bandwidth, fineness, hearing resistance, midpoint and stability. If you have not played LM1875, it is recommended to buy it and try it. If you have bought LM1875, users can buy it as an upgrade.

The principle is that the voltage of the two input terminals of the inverting amplifier circuit is always 0, which does not change with the input signal. The input voltage of the transistor (field effect transistor) at the input terminal of the amplifier is constant, and the bias state is always maintained at the appropriate operating point.

Generally, the output of a single LM8175 is 4A current, the official indicator, the driving sensitivity is low, and the large amount of speakers is useless with BTL, and the driving force will be overwhelmed. With 4 output, the driving current can be doubled to 16A current. This way, the sound field is better, the medium and low frequencies are fuller, and the power is also improved.

One channel is output by 4 pieces of LM1875, the quiescent current is 4 times higher than that of a single piece, the whole board current is about 0.5A, and the medium and small volume is pure Class A state. The human voice is very delicate and natural, full, and more comfortable than 1969 Class A. At the same time, it can be successful without cumbersome debugging

Product Highlights:
*Adopting a good-sounding CG circuit architecture, the sound is very delicate and durable, with a stable midpoint of 4 and X2 small Class A output
*40000UF large-capacity filtering, excellent for low-frequency diving
*Double-sided gold-plated military PCB is used, with good electrical conductivity and not easy to oxidize
*The output adds red copper pentoxide inductance to eliminate interference and clutter, and the sound quality is purer and more natural
*Japanese Omron protection circuit, more secure to use
*Full Advanced Component Configuration

PCB size "185MMX98MM The board is a double-layer immersion gold PCB.

After decades of classics, why are we still playing with the LM1875 power amplifier circuit?

Power range: AC12-AC22X2

Output power: 45W-8 ohms 60W 4 ohms (5W under pure A)

Impedance range: 1-8 ohms

Frequency response: 10HZ-40KHZ

Radiator size 200 * 40 * 62

Whole machine display:
Recommended transformer (18V is recommended)
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