Boss DD-7 - User Manual

The BOSS DD-7 Digital Delay is a versatile effects pedal designed to enhance guitar and other musical instrument sounds with a wide range of delay effects. It offers extensive delay times, multiple modes, and flexible control options, making it suitable for various musical applications from subtle ambience to complex soundscapes.

Function Description

The core function of the DD-7 is to produce delay effects, repeating an input sound after a set period. It achieves long delay times of up to 6.4 seconds, allowing for expansive and atmospheric sounds. Beyond simple repeats, the pedal offers a "HOLD" mode, which enables loop play or "sound on sound" recording for up to 40 seconds with monaural input, or 20 seconds with stereo input. This allows users to record a phrase and then layer additional performances over it, creating continuous backing tracks or intricate sonic textures.

The DD-7 features several specialized delay modes:

MODULATE: This mode adds a subtle chorus effect to the delayed sound, creating a pleasant undulation that enriches the tone.
ANALOG: This mode emulates the classic sound of the BOSS DM-2 analog delay pedal, characterized by a progressive change in the sound with each repetition, offering a warm and vintage delay character.
REVERSE: This mode produces a unique effect that simulates playing a tape backward, offering an "out of the ordinary" sound. In REVERSE mode, the E.LEVEL knob can be used to select between "Effect Sound + Direct Sound" or "Effect Sound Only" output.

The pedal also supports stereo operation, offering two new stereo modes in addition to 2-in/2-out true stereo connections. These modes enable stereo effects such as "Panning," where the delay sound moves between the left and right channels, and "Effect + Direct," which outputs the effect sound and the direct sound separately. When used as a stereo delay, the DD-7 offers three distinct operation modes: a completely independent delay for A and B, panning delay, and a stereo delay that imparts spatial broadness to the reverberant sound.

Usage Features

The DD-7 is controlled via a set of knobs and a pedal switch, providing intuitive access to its various parameters and functions.

Controls:

E.LEVEL (Effect Level) knob: Adjusts the volume of the effect sound. Turning it clockwise increases the effect volume. At the three o'clock position, the effect sound is at the same volume as the direct sound. In REVERSE mode, setting this knob to MAX outputs only the effect sound at the same level as the input.
F.BACK (Feedback) knob: Controls the feedback level, determining the number of times the delay sound is repeated. Turning it to the right increases repetitions. This knob is inactive in HOLD mode.
D.TIME (Delay Time) knob: Adjusts the delay time. Turning it clockwise lengthens the delay time. This knob is also inactive in HOLD mode. The range of delay times varies depending on the selected MODE.
MODE knob: Selects the delay effect mode (3200ms, 800ms, 200ms, 50ms, HOLD, REVERSE, ANALOG, MODULATE). Each setting corresponds to a different delay time range or a specialized effect.

Pedal Switch:

Effect On/Off: Pressing the pedal switch turns the effect on or off. The CHECK indicator lights red when the effect is ON. The DD-7 features a "seamless switching function," allowing the delay sound to decay gradually even after the effect is switched off. In HOLD mode, the effect cannot be switched on or off.
Tempo Input (Built-in Pedal): The pedal switch can be used to set the delay tempo in real-time. By holding the pedal for at least two seconds, the unit enters TEMPO mode (CHECK indicator lights green). Repeatedly pressing the pedal in time with the desired song tempo (CHECK indicator flashes red and green) sets the delay time. Holding the pedal again for two seconds completes the tempo setting.
HOLD Function Control: In HOLD mode, the pedal switch is used to initiate recording, stop recording and begin playback, start overdubbing, and stop playback (by pressing twice in quick succession).

External Control:

TEMPO/EXP jack: This versatile jack allows for connection of an optional external footswitch (BOSS FS-5U) or an expression pedal (Roland EV-5).
- External Footswitch (FS-5U): When connected, the FS-5U can be used to input the tempo, allowing for hands-free tempo control regardless of whether the effect is on or off.
- Expression Pedal (Roland EV-5): An expression pedal can be used to control the E.LEVEL, F.BACK, and D.TIME knobs in real-time. To set this up, hold down the built-in pedal and connect the expression pedal. Then, turn the E.LEVEL, F.BACK, and D.TIME knobs to set the maximum values of the ranges you wish to control. Pressing the built-in pedal again saves these settings.

Output Methods:

The DD-7 offers various output configurations by changing how it's connected to other devices, providing different delay effects:

Panning: With A input and A/B output, this creates a panning delay effect. This feature is not available in HOLD mode.
Effect + Direct: With B input and A/B output, this configuration outputs the effect sound and the direct sound separately.
Long Delay: With A input and B output, this doubles the maximum delay time available in most modes, offering extended delay capabilities.
Stereo Delay: With A/B input and A/B output, this enables various stereo delay effects, including independent delays for each channel, panning delay, and a stereo delay that adds spatial broadness.

Power Management:

The unit can be powered by a 9V battery (6LR61 alkaline recommended) or an optional AC Adaptor (PSA-series).
The INPUT-A (MONO) and INPUT-B jacks act as power switches; plugging in a cable turns the unit on, and unplugging turns it off.
The CHECK indicator also functions as a battery check; if it dims or no longer lights while the effect is ON, the battery is low and should be replaced.

Maintenance Features

Battery Replacement:

To replace the battery, loosen the thumbscrew on the pedal and open the pedal upward.
Remove the old battery and disconnect the snap cord.
Connect the snap cord to a new 9V battery, observing polarity (+ versus -).
Place the new battery inside the battery housing.
Slip the coil spring onto the spring base on the back of the pedal, ensuring the snap cord is not caught.
Close the pedal and fasten the thumbscrew securely.
It is recommended to use an AC adaptor due to the unit's relatively high power consumption, but alkaline batteries are suggested if battery power is preferred. Keeping batteries installed even when using an AC adaptor provides a backup in case of power interruption.

General Maintenance:

Always turn down the volume of connected equipment before turning the unit on or off to prevent sudden loud noises or potential damage.
The unit is equipped with a protection circuit, requiring a brief interval (a few seconds) after power-up before it operates normally.
Ensure proper connection cables are used; some cables with resistors may cause extremely low or inaudible sound levels.
Always turn on devices in the correct order (guitar amp last when powering up, guitar amp first when powering down) to prevent malfunction and damage to speakers and other devices.

Boss DD-7 Specifications

General

Effect Type	Digital Delay
Tap Tempo	Yes
Input Impedance	1 MΩ
Output Impedance	1 kΩ
Recommended Load Impedance	10 kΩ or greater
Delay Time	1 ms to 6400 ms
Modes	Modulation, Analog, Reverse
Outputs	Mono/Stereo
Power Supply	9V DC
Dimensions	73 x 129 x 59 mm
Weight	430 g
Current Draw	55 mA (DC 9V)