Sonodyne SLA 3010

GENERAL / PRODUCT IDENTITY

SPECIFICATIONS	DETAILS
Manufacturer	Sonodyne
Model	SLA 3010
Product Category	Professional Power Amplifier
Series	SLA Series (SLA 3003 – SLA 2015)
Rack Units	2RU (2 rack units)
Channels	2 (Dual-Channel)
Amplifier Class	Class H (multi-rail switching power supply)
Agency Approvals	CE; BIS IS616:2017; IEC60065:2014; IEC62368-1
Country of Origin	India (Sonodyne, Kolkata)
Manufacturer Address	98 NB Block E New Alipore, Kolkata 700053

POWER OUTPUT

SPECIFICATIONS	DETAILS
Output Power per Channel — 8 Ω (Stereo/Dual)	1000 W
Output Power per Channel — 4 Ω (Stereo/Dual)	1400 W
Output Power — 8 Ω Bridge-Mono	2800 W
Number of Output Channels	2
Bridge Mode Maximum Load	8 Ω (minimum recommended)
Bridge Output Consistency Check	2 × 1400 W (ch @ 4 Ω) = 2800 W ✓ (mathematically verified)

AUDIO PERFORMANCE

SPECIFICATIONS	DETAILS
Total Harmonic Distortion @ Rated Power	< 1% (less than 1%)
Signal-to-Noise Ratio (20 Hz–20 kHz)	105 dB
Frequency Response	20 Hz–20 kHz, ±0.5 dB
Damping Factor (Owner's Manual spec)	240
Damping Factor (Product Brochure)	>300 (stated as series minimum — see discrepancy note)
Inter-Channel Crosstalk	Reduced by independent per-channel power supplies (exact figure not specified by manufacturer)
IMD (Intermodulation Distortion)	Low (stated feature — exact figure not specified by manufacturer)

INPUT SPECIFICATIONS

SPECIFICATIONS	DETAILS
Input Connector Type	Balanced XLR female (3-pin)
Input Connectors per Channel	1 × Input + 1 × Link (parallel loop-through)
Input Impedance (Balanced)	20 kΩ
XLR Wiring Standard	IEC 60268: Pin 1 = GND, Pin 2 = HOT (+), Pin 3 = COLD (−)
Input Sensitivity — Setting 1	0.775 V (0 dBu)
Input Sensitivity — Setting 2	1.0 V (+2.2 dBu)
Input Sensitivity — Setting 3	1.4 V (+5.2 dBu)
Sensitivity Selection	3-position rear-panel slide switch per channel pair
Ground Lift	Rear-panel slide switch — disconnects input XLR ground from chassis ground

OUTPUT SPECIFICATIONS

SPECIFICATIONS	DETAILS
Output Connector — Type 1	Twist-lock speaker socket (Speakon-compatible), one per channel
Output Connector — Type 2	Heavy-duty binding post (red/black pair), one per channel
Twist-Lock Wiring (Dual/Mono)	Pin 1+: Positive; Pin 1−: Negative
Twist-Lock Wiring (Bridge)	Pin 1+: Ch1 Positive; Pin 2+: Ch2 Negative
Binding Post Wiring (Dual/Mono)	Red: Positive; Black: Negative
Binding Post Wiring (Bridge)	Ch1 Red: Positive; Ch2 Red: Negative

OPERATING MODES

SPECIFICATIONS	DETAILS
Dual Mode	2 inputs active, 2 independent outputs — standard stereo amplification
Mono (Parallel) Mode	Channel 1 input only — appears at both Ch1 and Ch2 outputs simultaneously
Bridge Mode	Channel 1 input only — Ch1 and Ch2 outputs combined in BTL configuration, single output
Mode Selection	3-position rear-panel slide switch

PROTECTION SYSTEMS

SPECIFICATIONS	DETAILS
DC Output Protection	Yes — mutes output on DC fault detection
Short-Circuit Protection	Yes — sustained short-circuit withstand
Thermal / Overheat Protection	Yes — heatsink temperature monitoring with automatic shutdown
RF Interference Filter	Yes — attenuates out-of-band RF signals at input
High-Frequency Overload Protection	Yes
Input Overload Protection	Yes
Mains Input Over-Current Protection	Slow-blow / time-delay fuse on rear panel
Internal Fault Protection	Yes
Built-In Intelligent Limiter	Yes — per channel, dynamic SOA control, senses output for clip/overheat limiting
PROTECT LED Indicator	Yes — front panel, illuminates on any protection event

FRONT PANEL CONTROLS & INDICATORS

SPECIFICATIONS	DETAILS
Volume / Level Controls	2 × calibrated detent rotary potentiometer (42 detent positions each)
SIGNAL LED	1 per channel — illuminates at 1 W output
CLIP LED	1 per channel — illuminates at onset of clipping
PROTECT LED	1 per channel — illuminates during protection event
POWER SWITCH	Rocker-type mains switch
Front Ventilation	2 × ventilation pockets feeding heat tunnel (must remain unobstructed)

REAR PANEL CONTROLS

SPECIFICATIONS	DETAILS
MODE Slide Switch	3-position: DUAL / MONO / BRIDGE
SENSITIVITY Slide Switch	3-position: 0.775 V / 1.0 V / 1.4 V
GROUND LIFT Slide Switch	2-position: GND / GND-LIFT
INPUT XLR Sockets	2 × balanced XLR female (one per channel)
LINK XLR Sockets	2 × parallel loop-through XLR (one per channel)
TWIST-LOCK Sockets	2 × twist-lock speaker outputs (one per channel)
BINDING POSTS	2 × pairs (one per channel)
FUSE	Slow-blow rear-panel accessible fuse — rating printed on backplate
MAINS CABLE	Integral 3-pin 15 A mains cable (non-detachable)

THERMAL MANAGEMENT

SPECIFICATIONS	DETAILS
Cooling Type	Forced air — front-to-rear via heat tunnel
Fan Type	Variable-speed intelligent DC fans (thermally controlled)
Heatsink Design	Special-design copper heatsinks in isolated heat tunnel
Dust Filter	Front-panel dust filter — reduces heatsink contamination
Thermal Isolation	Heat tunnel isolates heatsinks from rest of amplifier internals
Thermal Shutdown	Automatic output muting if heatsink exceeds maximum allowable temperature
Fan Behaviour on Power-On	Briefly increases speed then reduces — confirms thermal circuit operation

POWER SUPPLY

SPECIFICATIONS	DETAILS
Mains Input Voltage	230 VAC / 50 Hz
Input Power Consumption	1000 W
Measurement Standard	BIS IS616:2017 / IEC60065:2014 / IEC62368-1
Power Supply Architecture	Independent per-channel power supply (dual transformer / dual PSU)
Class H Rail Architecture	Multiple supply rails, real-time output monitoring, lowest sufficient rail always selected
Soft Start	Yes — prevents inrush current surge at power-on
Mains Connector	Integral 3-pin 15 A cable (non-detachable IEC-style plug)

PHYSICAL SPECIFICATIONS

SPECIFICATIONS	DETAILS
Width	483 mm (19-inch rack standard)
Depth	462 mm
Height	88 mm (2 rack units / 2RU)
Weight	20.4 kg (Owner's Manual) — note: Product Brochure states 20.5 kg
Chassis Material	Heavy-duty steel
Handles	Integrated front-panel handles
Rack Mounting	Standard 19-inch rack — 2 rack unit spaces required
Ventilation Clearance	Front and rear must remain unobstructed for airflow

CERTIFICATIONS & COMPLIANCE

SPECIFICATIONS	DETAILS
CE Mark	Yes — European Conformity
BIS Certification	BIS IS616:2017
IEC Standard	IEC60065:2014 and IEC62368-1
XLR Wiring Standard	IEC 60268

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1. PRODUCT OVERVIEW

The Sonodyne SLA 3010 is a high-power, 2-channel professional power amplifier positioned at the upper-mid tier of Sonodyne's SLA Series — a comprehensive family of nine models spanning dual-channel and four-channel configurations designed for the most demanding live sound, installation, and touring applications. Employing Class H amplifier topology, the SLA 3010 is rated at 1000 Watts per channel into 8 Ohms, 1400 Watts per channel into 4 Ohms, and 2800 Watts in bridge-mono mode into 8 Ohms, making it one of the most powerful Class H offerings in Sonodyne's catalogue and a compelling choice for engineers who require substantial headroom without compromising on audio integrity.

Sonodyne, headquartered in Kolkata, India, has built the SLA Series around a central engineering philosophy: that professional power amplification should combine genuine high-power output with exhaustive protection circuitry, high signal fidelity, and rugged long-term reliability — all within a standard 2RU rack chassis. The SLA 3010 embodies this philosophy through its independently powered dual-channel architecture, in which each channel is driven by a dedicated power supply. This design choice reduces inter-channel crosstalk at high frequencies and significantly narrows the difference in output power between the BCD (Both Channels Driven) and SCD (Single Channel Driven) conditions — a common weakness of amplifiers that share a single transformer across both channels.

The defining technical achievement of the SLA 3010's Class H topology is its multi-rail power supply, managed by a real-time control circuit that continuously monitors the amplifier's output voltage. At any given instant, the circuit selects the lowest power-supply rail voltage capable of supporting the required output swing. Because the output stage dissipates heat proportional to the difference between supply voltage and output voltage, this dynamic rail selection minimises thermal losses during low-to-moderate signal passages — which account for the vast majority of real-world programme material — while seamlessly switching to higher rails when transient peaks demand it. The result is an amplifier that runs substantially cooler and more efficiently than a conventional Class AB design at equivalent power ratings, while preserving the linearity and low-distortion characteristics that professional sound reinforcement demands.

Supporting the power stage is a large array of matched complementary output transistors operating in parallel, each selected for consistent linear transfer characteristics. This parallel topology distributes current stress across many devices simultaneously, maximising safe operating area (SOA) and ensuring stable, reliable operation even under sustained high-power conditions into demanding reactive loads. The SLA 3010 achieves a signal-to-noise ratio of 105 dB (20 Hz–20 kHz), total harmonic distortion of less than 1% at rated power, and a flat frequency response of 20 Hz to 20 kHz within ±0.5 dB — specifications that confirm this amplifier's suitability for full-range programme reproduction in professional environments.

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2. CLASS H AMPLIFIER TOPOLOGY: ENGINEERING DEEP-DIVE

Understanding Class H operation requires first understanding its predecessor, Class AB, which remains the topology of choice for Sonodyne's entry-level SLA 3003 and SLA 3004 models. In a Class AB amplifier, the output stage transistors operate from fixed supply rails — typically at a voltage high enough to support the maximum output swing. The fundamental inefficiency of this arrangement is that the supply rails are always at full voltage regardless of whether the programme material at a given moment requires it. During passages of moderate level — the majority of music and speech — the output devices must dissipate the difference between the fixed supply voltage and the comparatively modest output signal as waste heat. This is why Class AB amplifiers at high power ratings are heavy, hot, and require large heatsinks.

Class H solves this problem through what might be described as a dynamically tracked power supply. Multiple supply rails — typically three or more voltage levels — are pre-charged and held ready. A fast-responding control circuit monitors the instantaneous output voltage of the amplifier in real time. When the programme signal is low, the output stage is powered from a low supply rail, keeping transistor dissipation minimal. As the signal level rises toward a threshold, the control circuit seamlessly switches to the next higher rail — the transition occurring before the output stage would otherwise encounter clipping from an insufficient supply voltage. For the highest transient peaks, the uppermost rail engages. The key engineering challenge is ensuring that rail transitions are imperceptible in the audio output; Sonodyne achieves this through careful threshold spacing and fast switching circuitry.

The practical consequence for the SLA 3010 is that despite its 1000W/channel power rating, its thermal dissipation under typical programme material is a fraction of what a Class AB design of equivalent continuous power rating would produce. This translates directly to lower operating temperatures, reduced fan speed and noise during moderate passages, longer component service life, and the ability to sustain rated power output for extended periods without thermal shutdown — critical in touring and permanent installation scenarios where an amplifier may run continuously for many hours at high average levels.

It is important to contextualise the SLA 3010's power figures in light of Class H's real-world dynamic range. The rated 1400W into 4 Ohms represents 1.4 times the 8 Ohm figure rather than the theoretical 2× that would result from simple resistive impedance halving in an ideal voltage source. This is characteristic of all high-power professional amplifiers: the power supply rails, transformer VA rating, and output device current limits collectively impose a practical ceiling on the 4 Ohm output power. The bridge mode figure of 2800W into 8 Ohms is particularly revealing — it exactly equals 2 × 1400W, confirming that in bridge mode each channel drives a 4 Ohm effective load half (each channel sees 4 Ohms when 8 Ohms is presented across the bridge), and this result is internally consistent and mathematically validated.

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3. POWER OUTPUT & MATHEMATICAL VALIDATION

3.1 Published Power Specifications

3.2 Bridge Mode Mathematical Validation

In bridge-mono configuration, the two amplifier channels operate as a BTL (Bridge-Tied Load) pair: Channel 1 drives the positive terminal of the speaker load while Channel 2, receiving an inverted version of the same signal, drives the negative terminal. The load 'sees' the voltage swing of both channels added together. A speaker load of 8 Ohms connected across the bridge effectively presents 4 Ohms to each individual channel.

Verification: If each channel delivers 1400 W into 4 Ω, then bridge output into 8 Ω = 2 × 1400 W = 2800 W. This exactly matches the published specification, confirming internal consistency. ✓

3.3 Impedance Doubling Analysis

Theoretical ideal (voltage source): halving impedance from 8 Ω to 4 Ω should double output power — so 1000 W × 2 = 2000 W at 4 Ω. The SLA 3010's actual 4 Ω rating is 1400 W, representing a ratio of 1.4× rather than 2×. This is entirely characteristic of professional power amplifiers at this power level: the power supply transformer VA rating, rail voltages, and output device peak current are the limiting factors, not circuit topology deficiency. This measured "softer" impedance curve is typical across all Class H designs and does not represent a discrepancy — it reflects responsible, honest measurement methodology.

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4. AUDIO SPECIFICATIONS & PERFORMANCE

4.1 A Note on THD Specification

The SLA 3010 is rated at less than 1% THD at rated power. While this figure is higher than the sub-0.1% specifications achievable in Class AB studio amplifiers or the flagship SLA 2015 (Class H, <0.1%), it is entirely appropriate and industry-standard for a professional high-power Class H amplifier intended for sound reinforcement at live event levels. At moderate programme levels well below clipping — the typical operating condition for a properly gain-staged system — actual THD will be substantially lower than the rated maximum. The ±0.5 dB frequency response across the full 20 Hz–20 kHz audio band confirms excellent passband flatness, ensuring that no part of the programme spectrum receives undue colouration from the amplifier.

The 105 dB signal-to-noise ratio is particularly noteworthy. This is the highest SNR in the entire dual-channel SLA range (the SLA 3003 achieves 100 dB; SNR increases progressively up the range), reflecting the benefits of Sonodyne's independent per-channel power supply design — which reduces shared-rail noise coupling — and careful layout in the input and gain stages. In a typical sound reinforcement application, a 105 dB SNR means the noise floor of the amplifier will be more than 100 dB below a 1000 W output into 8 Ohms, rendering amplifier self-noise inaudible in virtually any practical scenario.

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5. PROTECTION CIRCUITS & INTELLIGENT LIMITING

The SLA 3010 incorporates one of the most comprehensive protection suites in its class. Sonodyne's engineering approach treats protection not as an afterthought but as a primary design objective — the amplifier is built to recover gracefully from real-world abuse conditions without sustaining damage or requiring service intervention. The following protection mechanisms operate simultaneously and independently:

1. DC Output Protection: Detects the presence of DC voltage at the speaker output terminals, which would immediately damage connected loudspeaker transducers. Upon DC detection, the output is muted instantly. This is critical — even a brief DC fault event can destroy horn drivers, tweeters, and voice coils worth many times the cost of the amplifier.
2. Short-Circuit Protection: The output stage is able to withstand a dead short across the speaker terminals without sustaining damage. The protection circuit detects the resulting current surge and limits output, preventing catastrophic transistor failure. This is essential in touring environments where connector faults and accidental cable shorts are real operational risks.
3. Thermal Protection: An independent thermal sensing circuit monitors the temperature of the output stage heatsink. If the heatsink temperature reaches the maximum allowable threshold — a condition that could otherwise damage the output transistors — the amplifier mutes its output and illuminates the PROTECT LED. This is distinct from the normal fan speed regulation, which is a continuous thermal management function; thermal shutdown is an emergency last resort.
4. RF Interference Filter: High-frequency RF signals, particularly those from nearby wireless transmitters, in-ear monitor systems, and mobile communication devices, can enter amplifier input stages and cause intermodulation distortion, instability, or damage. The integrated RF filter attenuates these out-of-band signals before they reach the gain stages.
5. High-Frequency Overload Protection: Separately from RF filtering, a dedicated high-frequency overload protection circuit guards against sustained high-frequency energy that could damage tweeters and horns connected through crossovers to the amplifier outputs.
6. Input Overload Protection: Limits the effect of excessive input signal levels, preventing overdriving of the input stage from causing harmonic products to enter the power stage.
7. Mains Input Over-Current Protection: A heavy-duty slow-blow fuse on the rear panel provides protection against mains-side faults, wiring errors, and sustained overload conditions that could create a fire hazard.
8. Built-In Intelligent Limiter (Dynamic SOA Control): Each channel incorporates an independent limiter that senses the amplifier's output and automatically reduces the input gain during excessive clipping or imminent thermal overload. This is Sonodyne's dynamic Safe Operating Area (SOA) control — it keeps the output transistors within their safe operating boundaries without requiring external limiting from the console or drive rack, providing a transparent safety net that is invisible during normal operation.

The front-panel PROTECT LED is the operator's primary indicator of any protection event. When illuminated, it indicates one of the following active conditions: overload at the input or output, DC detected at the output, or heatsink overtemperature. The amplifier will remain muted until the fault condition has cleared. In the case of thermal events, the fan will continue to run to cool the heatsink; audio output will resume automatically once safe temperatures are restored.

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6. THERMAL MANAGEMENT & COOLING ARCHITECTURE

The SLA 3010's cooling system is a purpose-engineered heat tunnel rather than a conventional open-chassis fan arrangement. Cool air is drawn in through two ventilation pockets on the front panel by high-speed fans positioned within the heat tunnel. This airflow path passes directly through a set of special-design copper heatsinks before exhausting from the rear of the chassis. The copper heatsink material is significant: copper has substantially higher thermal conductivity than aluminium (approximately 401 W/m·K versus 205 W/m·K), meaning it can transfer heat away from the output transistors more rapidly, reducing junction temperatures and extending device operating life.

The heat tunnel architecture serves a secondary purpose: by channelling airflow through a defined path, it thermally isolates the heatsink assembly from the rest of the amplifier's internal components — the input circuitry, power supply capacitors, transformer, and control electronics. Components sensitive to heat, such as electrolytic capacitors whose lifespan is strongly temperature-dependent (capacitor life halves for every 10°C rise above rated temperature), are therefore kept in a cooler, more stable thermal environment. The front-panel dust filter reduces the ingress of airborne particles that would otherwise accumulate on heatsink fins and fan blades, degrading thermal performance over time.

Fan speed is controlled by an intelligent variable-speed DC fan management circuit that continuously monitors heatsink temperature. At low power levels and cool ambient temperatures, the fan may run at low speed or not at all, resulting in near-silent operation. As heatsink temperature rises with increasing programme levels, the fan speed is increased proportionally. At full rated power, the fans switch to high speed. This variable-speed design serves a dual purpose: it minimises fan noise during passages where quiet operation matters (theatre, broadcast, orchestral reinforcement) while ensuring maximum cooling capacity is always available on demand.

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7. INPUT & OUTPUT CONNECTIVITY

7.1 Input Connections

7.2 Output Connections

7.3 Operating Modes (Rear Panel Mode Switch)

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8. FRONT PANEL CONTROLS & INDICATORS

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9. REAR PANEL CONTROLS

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10. BUILD QUALITY & FORM FACTOR

The SLA 3010 is constructed on a heavy-duty steel chassis, providing the structural rigidity and electromagnetic shielding that sustained touring and permanent installation demands. Steel's high mass density (approximately 7850 kg/m³) means that the chassis acts as an effective Faraday cage against external electromagnetic interference — important when the amplifier is rack-mounted adjacent to digital mixing consoles, signal processors, and wireless system receivers. The integrated handles on the front panel are an operational necessity for a 20.4 kg unit: safe handling of rack equipment above 15 kg requires positive grip points, and Sonodyne has incorporated these as a standard feature rather than an optional add-on.

The 2RU (88 mm) rack height positions the SLA 3010 well for density-optimised amplifier racks. At 462 mm depth, the amplifier requires a standard 450–500 mm deep rack enclosure — a depth well supported by all major professional rack manufacturers. The 483 mm width is the industry-standard 19-inch rack width. The non-detachable mains cable is a deliberate engineering decision: it eliminates the possibility of loose connection at the IEC socket caused by vibration during transport — a real failure mode seen in touring amplifiers with detachable cables — and provides a permanent, mechanically robust mains connection. The slow-blow fuse on the rear panel provides accessible overcurrent protection without requiring special tooling.

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11. POWER SUPPLY SPECIFICATIONS

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12. IDEAL APPLICATIONS & USE CASES

The SLA 3010's combination of high continuous power output, Class H efficiency, exhaustive protection, and flexible operating modes makes it a versatile workhorse across a wide range of professional audio environments. The following applications represent scenarios where the SLA 3010's specific capabilities provide a meaningful operational advantage:

1. Live Concert Sound Reinforcement: Driving full-range passive main PA cabinets or bass-heavy subwoofer arrays at indoor and outdoor concert venues — the 2800 W bridge output provides substantial headroom for high-SPL applications.
2. House of Worship PA Systems: Powering main loudspeaker systems in large sanctuaries and auditoriums, where sustained high-average-level operation and reliable protection circuits are essential for volunteer-operated systems.
3. Theatre & Performing Arts Centres: Driving passive flown or ground-stacked speaker systems in theatrical applications where the variable-speed fan's low-noise operation during quiet passages is a significant operational advantage.
4. Corporate Event & Conference Sound: Providing amplification for speech and background music in large conference halls and ballrooms, with the dual-channel capability allowing simultaneous main and fill coverage from a single amplifier.
5. Outdoor Festivals & Temporary Event Production: The robust steel chassis, exhaustive protection circuits, and thermal management system make the SLA 3010 well-suited to the temperature extremes and operational demands of outdoor event production.
6. DJ & Club Installations: Bridging the amplifier to deliver 2800 W into a single 8 Ohm high-power subwoofer, with the per-channel limiter preventing driver damage at high dance-floor SPL levels.
7. Multi-Zone Commercial Audio: Operating in dual mode to feed two independent zones from a single rack unit — suitable for lobby/foyer distributed audio, hospitality venues, and retail background music systems.
8. Rental Company Inventory: The unit's broad sensitivity range (0.775 V–1.4 V), flexible operating modes, link-through inputs, and robust construction make it a highly deployable workhorse in a rental fleet context.
9. Passive Studio Monitor Amplification: Driving high-power passive reference monitors (such as those used in large-format mixing rooms) where the SLA 3010's low noise floor (105 dB SNR) and flat frequency response provide accurate, uncoloured amplification.
10. Sports Venues & Arenas: Public address and music reinforcement in stadia and sports halls, exploiting the bridge mode's 2800 W output for driving high-efficiency line array column speakers over long distances.
11. Houses of Worship Stage Monitor Amplification: Using the mono (parallel) mode to drive two identical wedge monitors from a single input with matched levels, simplifying cabling and saving rack space.

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13. SLA SERIES POSITIONING: COMPARATIVE OVERVIEW

The SLA 3010 occupies a clearly defined position within the SLA Series. Understanding how it relates to the models above and below it allows system designers to select the most appropriate model for any given power budget and application:

Dual-Channel SLA Models: Comparative Specifications

★ = SLA 3010 (this document). The SLA 3013 (Class TD) sits alongside the SLA 3010 in price and power but uses a different topology — Class TD, which offers even higher 4 Ohm power (2150 W vs 1400 W) but with a lower 8 Ohm bridge output (2700 W vs 2800 W). The SLA 3010's Class H topology is generally preferred for applications where bridge mode into 8 Ohms is the primary use case, while the SLA 3013 is preferred where maximum 4 Ohm stereo output is the priority.

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