# **BOUM: Analog Stereo Warming Unit**

BOUM is a full analog stereo warming unit combining an easy-to-use compressor, a versatile distortion generator, and a smooth hi-cut filter. It is designed to add warmth, thickness, and character, or apply severe distortion and extreme compression treatments.

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## **CORE FEATURES**

* **Analog Signal Path:** 100% analog signal path and sidechain.
* **One-Knob Compressor:** Control Ratio (1:1 to 1:-1) with adjustable Attack and Release.
* **4 Distortion Circuits:** Boost, Tube, Fuzz, and Square.
* **Variable Hi-Cut Filter:** 12 dB/octave (20 kHz to 20 Hz).
* **Lo-Cut Filter:** 6 dB/octave (Flat, 75 Hz, 150 Hz, 300 Hz).
* **Noise Gate:** Threshold up to 0 dB for creative chopping effects.
* **Memory & Control:** 36 user presets and full MIDI control.

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## **THE SIGNAL STAGES**

### **1. INPUT GAIN**

Boost your signal up to **+18 dB** to adapt to various levels, improve distortion content, and increase compressor sensitivity.

> **Settings:** 0 dB, +6 dB, +12 dB, +18 dB

### **2. COMPRESSOR**

A unique one-knob interface controlling **Threshold, Ratio, and Makeup Gain** simultaneously.

* **Ratio Range:** 1:1 (None) → $\infty$:1 (Limiter) → 1:-1 (Dynamic Reversal).
* **Attack Times:** 50µs, 330µs, 1ms, 3.3ms, 10ms, 33ms.
* **Release Times:** 50ms, 100ms, 250ms, 350ms, 500ms, 1s.

### **3. LO-CUT FILTER**

Attenuates bass frequencies **before** the distortion stage (6 dB/octave). This keeps the low end clean and makes the distorted signal easier to mix.

> **Settings:** Flat, 75 Hz, 150 Hz, 300 Hz

### **4. DISTORTION GENERATOR**

Choose from four distinct analog circuits:

* **BOOST:** Soft clipping; ideal for subtle harmonic enhancement.
* **TUBE:** Asymmetrical distortion (MOSFET); generates 2nd-order harmonics.
* **FUZZ:** Symmetrical hard clipping; sounds like an overdriven mixer preamp.
* **SQUARE:** Pure square wave generator based on a comparator; the ultimate fuzz.

### **5. HI-CUT FILTER**

A musical 12 dB/octave filter used to soften high frequencies and "tame" harsh distortions.

### **6. NOISE GATE**

Removes floor noise or creates rhythmic "chopping" effects.

> **Thresholds:** OFF, -50 dB, -40 dB, -30 dB, -20 dB, -10 dB, 0 dB.

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## **TECHNICAL DEEP DIVE: THE COMPRESSOR POT**

The **COMPRESSOR** pot simplifies complex dynamics into a single turn:

1. **Threshold:** Varies between -30 and -15 dB.
2. **Ratio:** Increases as you turn the knob.
3. **Makeup:** Automatically compensates for the volume loss caused by compression.

**Understanding the 1:-1 Ratio:**
This is "over-compression." A 1 dB increase at the input above the threshold results in a 1 dB *decrease* at the output. This creates a "pumping" or dynamic reversal effect.

| Ratio Layout |
| --- |
| 1:1 (Clean) |
| 5:1 |
| 10:1 |
| INF:1 (Limiter) |
| 1:-0.3 |
| 1:-0.6 |
| 1:-1 (Reversal) |

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## **SIDECHAIN & GATE BEHAVIOR**

When a signal is connected to the **Sidechain (SC) Input**:

* **If Gate is NOT "OFF":** The SC input acts as a **Gate Trigger**. The BOUM signal only passes (opens) when a signal is detected at the SC input.
* **If Gate is "OFF":** The SC input controls the **Compressor** normally (ducking/external triggering).

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## **INTERFACE CONTROLS**

BOUM features 6 function keys. Press a key to select a parameter, use the **DATA** pot to change the value, and press the key again to exit.

1. **In Gain:** Input buffer gain.
2. **Attack:** Compressor response speed.
3. **Release:** Compressor recovery speed.
4. **Lo Cut:** Pre-distortion filter.
5. **Disto:** Circuit selection.
6. **Gate:** Noise gate/chopper threshold.

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