From JDK Audio (Arsenal by API)

The JDK Audio R24 is a dual-channel, four-band parametric equalizer designed to deliver classic analog tone shaping and precise frequency control in a rugged 2U rackmount chassis. Built by API Audio under the JDK brand, the R24 is based on the legendary circuitry of the classic ATI Paragon live mixing console, offering musical, smooth equalization that excels across individual tracks, sub-mixes, and master stereo buses.

Each channel of the R24 features four continuously variable frequency bands, each with overlapping frequency ranges, ±12 dB of boost/cut control, and custom-designed circuit topology that ensures minimal phase distortion and maximum signal headroom. Engineered with clean, high-headroom operational amplifiers and balanced XLR/TRS inputs and outputs, the R24 combines the warmth, punch, and reliability of API manufacturing with an intuitive interface for studio tracking, mixing, and live sound reinforcement.

Key Features

  • Dual-Channel 4-Band Parametric EQ: Two independent channels of 4-band equalization with continuously variable frequency and gain controls.
  • ATI Paragon Console Heritage: Circuit architecture derived from the famous ATI Paragon console, renowned for its musical filter shapes and pristine signal path.
  • Overlapping Frequency Bands: Wide, overlapping frequency coverage across all four bands allows for precise surgical cuts or broad, gentle tone shaping:
  • Low Band: 20 Hz to 200 Hz
  • Low-Mid Band: 100 Hz to 2 kHz
  • High-Mid Band: 1.5 kHz to 15 kHz
  • High Band: 5 kHz to 20 kHz
  • Symmetrical Equalization: Reciprocal boost/cut curves deliver consistent phase response whether boosting or cutting.
  • Hardwire Bypass Switch: Dedicated per-channel bypass switch connects input directly to output for true A/B monitoring.
  • High-Headroom API Construction: Built to API's rigorous quality standards, providing high output capability (+28 dBu) and low noise.
Form Factor
2U Rackmount
Channels
2 (Dual Mono / Stereo)
Inputs/Outputs
Balanced XLR and 1/4" TRS per channel
Frequency Response
±0.5 dB, 20 Hz to 20 kHz
Maximum Output Level
+28 dBu
THD+N
< 0.005% @ +4 dBu (20 Hz to 20 kHz)
Signal-to-Noise Ratio
> 100 dB below +4 dBu output
Gain Control
±12 dB per band (continuously variable)
Dimensions (W × H × D)
19" × 3.5" × 10" (48.3 cm × 8.9 cm × 25.4 cm)
Weight
13.0 lbs (5.9 kg)

Warranty

This item is sold without the Sound Pure 3-year warranty (used / B-stock / dealer-exempt). Coverage terms for items in this category live in Terms & Conditions, Section 27.

Returns

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Sound Pure Studios Control Room A — Durham, NC

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