Leading Tier-1 automotive component manufacturer SPR Auto Technologies Ltd, formerly Shriram Pistons & Rings Ltd, is advancing a speaker-less interior acoustic system for the domestic market.
Following its acquisition of Grupo Antolin's Indian interior and lighting business divisions, SPR Auto has completed a proof-of-concept for acoustic headliner technology with an Indian vehicle manufacturer.
The system utilizes the vehicle's interior roof lining as a primary acoustic membrane. Instead of packaging conventional heavy magnetic speakers within the cabin, the technology relies on top-mounted agitators that generate controlled vibrations directly through the roof fabric to produce sound.
Krishnakumar Srinivasan, Managing Director and CEO of SPR Auto Technologies Ltd, noted the shift away from traditional audio hardware. "The headliner acts as a speaker," Srinivasan said. "The fibre that you have acts as a membrane. And you have agitators on the top to ensure that it creates the vibration and creates the sound...The speaker is your fabric," he said. "You get rid of all the speakers," he told Autocar Professional on the sidelines of an industry event recently.
By eliminating standalone speakers from the roof or pillars, automakers can reduce overall vehicle weight, simplify complex wiring harnesses, and free up critical interior cabin space. The development is part of SPR Auto's broader efforts to upgrade its technological offerings.
Through extensive business process re-engineering over the last seven years, the company has transitioned from a legacy mechanical powertrain supplier into a diversified Tier-1 entity featuring five distinct business divisions: legacy components, electric motors, precision plastics, interiors, and lighting.
Global Context and Local Implementation
The efforts by SPR Auto are sure to be be watched keenly by the auto industry, considering that the technology has to clear various levels of hurdles before it could become commercially acceptable. Some of the reasons are technical. For instance, the Standard automotive headliners (typically thermoformed PET/polyurethane composites) lack the uniform density, stiffness, and controlled excursion required of a true speaker cone.
Exciting the roof fabric to produce adequate sound pressure levels, particularly low-frequency bass—presents severe risks of Total Harmonic Distortion (THD) and sympathetic rattles across roof bows, wiring looms, and panoramic sunroof frames. Furthermore, vibrating the top membrane raises unaddressed cabin isolation issues, as sound can radiate outward through the roof sheet metal.
Globally, the concept of surface-actuated vehicle audio has been explored over the past decade. Suppliers such as Continental, in partnership with audio specialist Sennheiser, introduced the system around 2020, which similarly used actuators to vibrate interior surfaces like A-pillars, door panels, and roof liners to save space and reduce weight.
Beyond the Continental and Sennheiser partnership, South Korean technology major LG Display has been a primary global driver of speaker-less automotive audio. Introduced in late 2022 and recognized at CES 2023, LG Display’s 'Thin Actuator Sound Solution' eliminates traditional voice-coil audio hardware. Instead, the company utilizes passport-sized, film-type exciters. When integrated into the vehicle's structural surfaces, such as headliners, dashboard pillars, door panels, and seat headrests, these actuators vibrate the materials to generate a 3D acoustic soundstage.
Within the Indian automotive ecosystem, indigenous commercialization of surface-actuated acoustic technology has remained virtually non-existent prior to SPR Auto’s initiative.
While global Tier-1 suppliers and consumer electronics giants have demonstrated these systems extensively, their application has been primarily targeted at premium European and North American vehicle architectures.
High component costs and complex acoustic calibration requirements have historically restricted their entry into the domestic Indian market.
It is in this context that SPR Auto's development marks a specific push to commercialize acoustic headliner technology within the highly cost-competitive Indian automotive ecosystem.
While removing conventional voice-coil speakers saves copper and magnet weight, multi-channel exciters and specialized Digital Signal Processing (DSP) amplifiers required for complex surface calibration are notoriously expensive. It will be interesting to see if SPR Auto's solution is economically competitive against standard 4-speaker OEM layouts in price-sensitive Indian vehicles.
Balancing Capacity with Technological Upgrades
Between FY20 and FY26, consolidated revenue at SPR Auto Technologies rose from Rs 1,626.62 Crore to Rs 4,571.30 Crore, a 18.8% CAGR, while net profit climbed from Rs 73.04 Crore to Rs 561.40 Crore at a 40.5% CAGR and EBITDA advanced from Rs 201.84 Crore to Rs 961.30 Crore at a 29.7% CAGR, as the piston-and-ring specialist converted India’s post-pandemic vehicle recovery into sustained scale and then layered on inorganic expansion that pushed margins and earnings faster than the top line.
Growth was powered first by a sharp rebound in OEM and aftermarket demand across commercial vehicles, passenger cars, two- and three-wheelers and tractors, then by a deliberate multi-year M&A push into adjacent technologies; majority control of EMF Innovations to enter the EV powertrain space (2022), a Rs 222 Crore investment for a 75% stake in Takahata Precision India (2023), full ownership of TGPEL Precision Engineering (2024), the Karna Intertech bolt-on (2025), and the €159 million purchase of Grupo Antolin’s India lighting and interiors arms (late 2025), backed by a Rs 1,000 Crore QIP in August 2026 to fund further acquisition-led growth and capex, turning a traditional engine-components franchise into a broader auto-tech platform with markedly higher profitability over the six-year span.
To sustain this upward trajectory, the company is deploying capital across three primary areas: expanding existing manufacturing capacity to meet a surge in domestic vehicle volumes, funding advanced technology integration within current product lines, and pursuing new mergers and acquisitions.
"We always have a theory of putting in the capacity ahead of the market," Srinivasan stated. He added that the recent rapid market growth requires continued capital allocation for both existing infrastructure and new technology integration to avoid capacity constraints.
Additionally, the company is actively engineering hydrogen pistons and components for multi-fuel and flex-fuel engines. "We are probably the only ones to have developed pistons for E85. And it works very well, absolutely very well. So, we have to put a lot of money for technology development" he continued.
Future M&A and Capital Allocation
Furthermore, SPR Auto is evaluating additional acquisitions to build capability in mechatronics and thermal management systems. The supplier's focus on thermal management is directly driven by increasing heat loads in modern vehicle architectures.
The rapid adoption of panoramic sunroofs, combined with higher-density power electronics, such as 3-in-1 and 4-in-1 electric motor assemblies and controllers has created severe thermal challenges for original equipment manufacturers.
"We are looking at mechatronics in a big way. We are looking at thermal management because what's happening is as the industry is growing, you are realising that the heat generation that is happening in the car is very, very high," the top executive noted, highlighting that OEMs are increasingly shifting toward cellular architectural models to isolate and cool controller pockets.
In mechatronics, SPR Auto remains open to full acquisitions or joint ventures to localize advanced electronic and mechanical systems for domestic OEMs.
Across all expansion vectors, proprietary technology serves as the primary investment filter. Conversely, SPR Auto is actively ruling out acquisitions in mature or price-pressured segments that lack a clear technological differentiator. When asked if they will be open to evaluating opportunities in traditional chassis components, such as standard suspension systems or exterior lighting, the company leadership expressed skepticism over thin margins, high capital requirements, and intense market saturation.
"If you don't have a common technology thread, I don't think it is going to be a very successful thing. We don't want to go beyond run-of-a-mill kind of an item," Srinivasan explained.
Way Forward
As vehicle architectures evolve to prioritize cabin space and energy efficiency, acoustic headliners indicate a functional step toward reducing component mass. For SPR Auto, successfully commercializing the technology will serve as a critical test of its ability to integrate the newly acquired Antolin divisions and transition up the value chain from basic trim manufacturing to advanced interior electronics.