API 535-LA
Best musical compression for professional audio engineers.
This 500-Series Line Amplifier is designed to infuse your audio signals with classic warmth and character. It offers exceptional versatility, capable of both boosting and attenuating levels to enhance digital sources, keyboard tones, or enrich any mix. Its fully discrete circuit, featuring renowned op-amps and proprietary transformers, delivers the signature sonic signature. Precise control is achieved through a variable input trim, a 20dB pad, polarity switch, and calibrated output levels, ensuring consistent and high-quality sound.
$565.25
Owner Satisfaction
4.7
/ 5
Category Rank
58
/ 606
#58 in Microphone Preamps
Price vs Category Average
-62%
Below average
Frequency Response
3020
/ Hz-kHz
Who it's for
- Audio engineers needing to maintain signal integrity across their studio.
- Producers seeking to infuse their mixes with a classic analog sonic character.
- Studio professionals requiring precise level control and subtle frequency adjustments.
Who should skip it
- Budget-conscious home studio owners seeking cost-effective signal solutions.
- Musicians expecting dramatic sonic changes from every studio hardware purchase.
- Newcomers to hardware who do not yet own a 500-series compatible rack.
Performance breakdown
Sonic Character
Delivers that unmistakable, punchy API warmth to any digital source.
Gain Versatility
Handles everything from subtle attenuation to aggressive boosting with ease.
Build Integrity
Discrete circuitry and robust transformers ensure legendary, long-lasting reliability.
Signal Precision
Calibrated level modes provide consistent, repeatable results for professional workflows.
Integration Ease
Standard 500-series format makes slotting into existing racks seamless.
Control Depth
Essential tools like polarity and pad switches offer necessary signal management.
Key Specs
Frequency Response
30Hz-20kHz
THD+N
0.006% at factory CAL Level setting (+4dBu)
Noise floor
-85dBu at factory CAL Level setting
Gain Range
-inf. to 53dB
Maximum Input level
+32 dBu, balanced (with PAD)
Maximum Output level
+32 dBu MAX, balanced (1kHz)
Input Impedance
Greater than 20,000 ohms
Output Impedance
Less than 75 ohms
Know before you buy
The 535-LA is a line amplifier designed to add the classic API warmth and character to digital signals, keyboards, or pre-recorded tracks. It acts as a sonic enhancement tool rather than a traditional microphone preamp, giving your audio a professional, analog polish.
No, the 535-LA is a line-level amplifier, not a microphone preamp. It is designed to process line-level signals, meaning it lacks the high gain and phantom power required to drive microphones.
The calibrated level mode ensures consistent gain staging across your signal chain. By setting the unit to this mode, you can easily match levels between different sessions or units, making it much simpler to maintain a predictable, high-quality signal flow.
No, the 535-LA is strictly a line amplifier. It focuses entirely on providing high-quality, discrete circuit gain and tonal coloration without adding any built-in equalization or dynamics processing.
These controls provide precise gain staging, allowing you to push the signal for more saturation or attenuate it to prevent clipping. The 20dB pad is particularly useful for taming hot signals from modern digital interfaces or synthesizers before they hit the amplifier circuit.
Yes, the 535-LA is built to the standard 500-series form factor. It will fit into any standard 500-series chassis that provides the necessary power.
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$565