API 2500+ Stereo Bus Compressor

The API 2500+ is a high-end stereo/dual mono compressor that delivers legendary punch, tone shaping, and dynamic control, making it an essential tool for both mixing and mastering engineers. Housed in a 19-inch rack-mountable unit, the 2500+ offers dual-channel operation that can be configured for linked stereo processing or independent dual mono use, all while maintaining API’s signature analog sound quality.

A key feature of the 2500+ is the patented THRUST® circuit — a unique high-pass filter placed before the RMS detector that preserves low-end punch while compressing, giving your mixes the “chest-hitting” energy that API is known for. Combined with adjustable threshold (-20 to +10 dBu), variable ratio, attack, and release times, and switchable “Old” (feedback) and “New” (feed-forward) compression styles, the 2500+ gives engineers precise control over tone and transient response.

Also included is the new Mix/Blend circuit, allowing parallel compression or crossfading between dry and processed signal. With three operation modes — OFF, Cross (X), and Parallel (||) — this feature adds serious versatility for modern mixing workflows. The auto-makeup gain function ensures consistent output levels as you tweak compression settings.

API’s legendary 2520 op amps are at the core of the 2500+, ensuring rich harmonic content and unmistakable character. The unit also includes balanced sidechain inputs, soft/medium/hard knee options, and a fully discrete analog signal path with a hard relay bypass for true signal transparency when bypassed.

Key Features:

• Stereo or dual mono operation with variable channel linking
• Expanded variable threshold: -20 dBu to +20 dBu
• Selectable ratio, attack, and release times
• THRUST® circuit with 3 settings for low-end punch
• “Old” (feedback) and “New” (feed-forward) compression modes
• Soft, Medium, or Hard knee for flexible compression behavior
• New Mix/Blend control for parallel or crossfade compression
• Auto or manual gain makeup
• Balanced 1/4″ sidechain inputs
• Fully balanced signal path with API 2520 op amps
• Output clips at +32 dBu
• Over Threshold LED for visual compression monitoring
• Dual analog VU meters showing input, output, and gain reduction
• True hard relay bypass
• Made in the USA with API’s 5-year parts warranty

The API 2500+ is a powerful and musical stereo bus compressor designed to bring out the best in your mixes — from subtle glue to aggressive punch, always with that unmistakable API sound.