Enhancing DIY Audio Amplifier with Sony Cinema Space — LA2615 AViSS 3D Surround Algorithm
For DIY electronics and audiophile enthusiasts, the joy of continuously refining and improving audio systems is truly delightful. In my latest endeavor, I took the opportunity to enhance the DIY audio amplifier that I had built previously by incorporating a surround sound feature. (see my previous post about amplifier: https://medium.com/@rasansmn/building-my-diy-stereo-amplifier-a-step-by-step-journey-ab43e0ab4e72)
The Challenge
A typical stereo amplifier is limited to two channels. How could I achieve a surround sound experience without the complexity of adding more channels?
AViSS 3D Surround Algorithm
Enter the LA2615, an Analog Surround IC featuring the AViSS 3D Surround Algorithm a proprietary technology by SANYO Electric. This ingenious technology, initially commercialized by Sony under the name “Cinema Space” in their hi-fi audio systems, transforms a stereo image into a virtual surround sound, adding a new dimension to the audio experience.
Schematic Diagram and Components
The implementation involves a basic circuit that requires only a few external components.
Datasheet of the IC: https://www.digchip.com/datasheets/parts/datasheet/413/LA2615M-pdf.php
IC Features:
- It supports a wide operating supply voltage range, making it versatile for various applications.
- Adjustable surround signal level for customization.
- Low-noise low-distortion bypass mode for pristine audio.
- It creates a natural feeling of spaciousness without compromising tonal coloration.
- Clear vocal positioning, maintaining the center of the sound.
- Available in miniature packages: 16-pin DIP (LA2615) and 16-pin MFP (LA2615M).
Implementation Journey
While I stumbled upon a few applications of LA2615 in service manuals of hi-fi systems by Sony and Sanyo, I noticed a gap in DIY projects featuring this IC. Undeterred, I ordered the IC, which arrived in a compact SMD-type package instead of the one I intended. No matter, I decided to take on the challenge and implemented the circuit on a vero board, employing a bit of a hack to solder the IC.
This is how it has been soldered
The assembled circuit has audio input and output for two channels, the surround bypass switch, and the connection to the power supply.
Integration with the Amplifier
With ample space in my amplifier cabinet, I easily found the place to locate it. I incorporated the surround sound circuit just between the audio input source and the tone-controller unit.
Testing and Results
Watch the short video I published on YouTube
Notable Aspects
- The IC preserves the original tone of the music, ensuring fidelity.
- No unwanted reverb effect is added, providing a natural surround sound experience.
- True surround sound: The direction of the sound is distinctly felt, creating a spacious auditory effect.
Summary
Implementing the Sony Cinema Space using the LA2615 Surround IC, featuring the AViSS 3D Surround Algorithm has added a new layer of sophistication to my audio amplifier. The result is an immersive audio experience that remains true to the original music while expanding the spatial dimensions of the soundstage. It’s a testament to the endless possibilities for audio enthusiasts willing to explore and experiment in the world of DIY audio.
