Tag Archive for オーディオアンプ

Monitoring Amplifier モニターアンプ P1

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Hello, こんにちは,


I like listening to loud music usually, i like to feel the impact of instruments close to live levels. Of course this is not always possible especially after work at late hours.


To overcome this I decided to build a monitoring amplifier this weekend. It will allow me to see the level of the source before coupling to the power amp and also to switch speakers off and just use headphones.

モニターアンプこの週末を構築することを決めた。ソースのレベルをチェックすることができます, そしてまた、オフスピーカーを切り替え、ヘッドフォンを使用しています。

It is also important to have a good tone control circuit to adjust loudness at low levels.


A first block diagram is presented below. アンプのブロック図。

Monitor audio Amplifier

Looking through my things to select components for this project, I found the chassis from the preamplifier module of a soviet Reel to Reel deck Rostov 105. The chassis has all the controls i needed on the front panel including two nice needle VU-meters.

amp chasis

I took the chassis down and cleaned it and i verified all the pots and switches and cleaned them.

Audio Monitor Amplifier

For Power Amplifier i have a LM3886 stereo kit which will be extremely useful. I used this kit for a while and it has a decent sound being one of the best audio chips in my opinion. I attached this kit to a heatsink from a Yamaha A-500.

The kit also comes with a dual VCA chip for DC volume control, the M5283P. This is a very good solution to keep noise from potentiometer out of audio path.

モニターアンプM5283 dual VCA


I built a power supply for the amplifier section and mounted them on the chassis.

LM3886 Audio Amplifier

LM3886 power amplifier

LM3886 Audio Amplifier

LM3886 Audio Amplifier

Potentiometer controlling the VC input of the dual VCA chip.


LM3886 Audio Amplifier

In the next article i will discuss more about the VCA and build the tone control, metering circuits.

Thank you for visitng,