Boss DD-3A, Boss DD-3B, Digital Delay DD-3, Digital Delay DD-3T Service Notes

SERVICE NOTES

Third Edition

Issued by RJA

Copyright © 2002 ROLAND CORPORATION

All rights reserved. No part of this publication may be reproduced in any form without the written permission
of ROLAND CORPORATION.

Printed in Japan

(0800)

(AS)17059557E3

May 2002

DD-3(T)

SPECIFICATIONS.............................................................2

LOCATION OF CONTROLS,PARTS LIST ...................3

EXPLODED VIEW,PARTS LIST ..................................... 4

PARTS LIST........................................................................5

ADJUSTMENTS ................................................................8

CIRCUIT BOARD..............................................................9

CIRCUIT DIAGRAM......................................................10

WARNING

There are three types of DD-3(T) with different circuitry called “DD-3”, “DD­3A” and “DD-3B”. The pedals of all three types are labeled “DD-3”.

We call the new type of this model, DD-3B for identifying the old type and
new type for convenience on service system.

Check the model name as follows.

Of the three types, only the appearance of the “DD-3” is different. Identify the
“DD-3” or the “DD-3A or DD-3B” by the shape of the adapter jack as shown in
the following figure.

The appearance of the “DD-3A” and the “DD-3B” are the same. Due to a
DRAM change, it has been changed to “DD-3B” from serial No. SO91200 of
1912LOT (produced in August 2001). It can be identified by the serial number.
The “DD-3A” and “DD-3B” can also be identified by the silk-screen printing
on the board.

When referring to the service notes or ordering parts, check the model name
using the above process.

This service note is for the “DD-3B”. Refer to “DD-3A SERVICE NOTES”
(#17059557) when repairing the DD-3A. Variable resistor, switch and
mechanical parts for the “DD-3A” and “DD-3B” are compatible. Refer to “DD­2/3 SERVICE NOTES” (#17059183) when repairing the DD-3.

fig.notice

DD-3A or DD-3B

DD-3

2

May 2002

SPECIFICATIONS

Power Supply

DC 9 V; Dry battery (6AM6/9V)

AC Adaptor (PSA-series: Option)

Current Draw

45 mA to 65 mA (DC 9V)

Controls

Pedal Switch

EFFECT LEVEL

FEEDBACK

DELAY TIME

MODE SELECTOR Switch

Indicator

Check Indicator (serves also as battery check indicator)

Jacks

INPUT

DIRECT OUTPUT

MAIN OUTPUT

AC Adaptor

System

Analog logalithmic compression and 12 bit quantizing system

Delay Time

12.5 ms (MIN) to 800 ms (MAX)

S (Short) 50 ms (12.5 ms to 50 ms)

M (Middle) 200 ms (50 ms to 200 ms)

L (Long) 800 ms (200 ms to 800 ms)

Hold Time

200 ms (MIN) to 800 ms (MAX) in Hold mode

Frequency Response

Delay Sound: 40 Hz to 7 kHz; +1/-3 dB

Direct Sound: 10 Hz to 60 kHz; +1/-3 dB

Residual Noise

-95 dBu (IHF-A, Typ.)

Input Impedance

1 M ohm

Output Load Impedance

10 k ohm or greater

Dimensions

73 (W) x 129 (D) x 59 (H) mm

2-7/8 (W) x 5-1/8 (D) x 2-3/8 (H) inches

Weight

450 g / 1 lb (including battery)

Accessories

OWNER’S MANUAL ENGLISH(#2603768702)

JAPANESE(#2603768603)

Dry Battery(#********); 6AM6/9V (Alkaline)

Leaflet (“USING THE UNIT SAFELY,” “IMPORTANT NOTES,” and
“Information”)

Options

AC Adaptor PSA-Series

*0 dBu = 0.775 Vrms

3

DD-3(T)

LOCATION OF CONTROLS,PARTS LIST

fig.panel

No.

PART CODE PART NAME DESCRIPTION
1 2253753801 PSA CAUTION 253-538
2 2221740401 PANEL
3 22017993RT CASE
4 2247726200 KNOB (BLUE) 247-262

13279869 POTENTIOMETER RKO971110 50KB
5 13449105MF JACK HTJ-064-14I
6 2235730400 FOOT BASE (PEDAL MAT) 235-304
7 2202785100 BOTTOM COVER 202-851
8 2235730500 BOTTOM BASE 235-305
9 G253751603 BOTTOM CAUTION PSA FCC/CE/C-TICK/EMC GRY
10 13449711 AC ADAPTOR JACK HEC-0470-01-630
11 1502928100 LED (RED) L-34HDSL
12 2247726200 KNOB (BLUE) 247-262

13119308 SWITCH (ROTARY) SBM1024 (SRBM 14011A)
13 2247726200 KNOB (BLUE) 247-262

13289126 POTENTIOMETER RK0971110 10KA 15MM
14 F3449112 JACK (STEREO) HTJ-064-13D
15 13449140MF JACK (STEREO) HTJ-064-14D
16 22187547RT PEDAL