This is a powerful but sensible Windows application that lets you record, arrange, edit, and render multi-track waveform audio. 

It provides an extensive set of features, but is a very small and lightweight application (the installer is less than 1 megabyte, and includes many effects and a sample project).

Also, it supports ASIO, Kernel Streaming, WaveOut, and DirectSound for playback and recording. It reads WAV, OGG, and MP3 files, and records WAV files. 

You can arrange any number of items in any number of tracks and use audio processing plug-ins (DirectX and Jesusonic).

Moreover, it also supports volume, pan controls and envelopes per track, multi-layer undo/redo, and user creatable color themes.

Features of Cockos REAPER 6
Tool-less mouse interface
Excellent low-latency performance
Multiprocessor capable
Direct multi-track recording to many formats including WAV/BWF/W64, AIFF, WavPack, FLAC, OGG, and MIDI.
Extremely flexible routing
Fast, tool-less editing
Supports a wide range of hardware (nearly any audio interface, outboard hardware, many control surfaces)
Support for VST, VSTi, DX, DXi effects
High quality 64 bit effect suite
Technical Details and System Requirements
Supported OS: Windows 7/8/10
Processor: Pentium IV or higher
RAM: 1 GB RAM (2 GB recommended)
Free Hard Disk Space: 200 MB or more