Nady Audio DSP 256 User manual

DSP 256
18-bit Digital Sound Processor
OWNER’S MANUAL
DSP256manual 11/9/01 10:17 AM Page 1

3
Warning ..................................................................4
Installation
Inspection................................................................5
Desktop Use ..........................................................5
Rackmounting ........................................................5
Controls, Connections, and Operation
Front Panel Controls and Use
Input Level Control ................................................6
Mix Level Control....................................................6
Output Level Control ..............................................7
Peak Level LED......................................................7
Program Select Control ..........................................7
Variations Select Control ........................................7
Rear Panel Connections and Use
Power Jacks............................................................8
Bypass Jacks..........................................................8
Input (Left/Mono &Right) Jacks ..............................8
Output (Left & Right) Jacks ....................................9
Setup and Operation
Connecting Directly to an Instrument ..................10
Connecting Directly to a Mixer Console ..............10
Typical Connections
1. Mono In, Mono or Stereo Out ....................11
2. Stereo..........................................................11
3. Using Mixer Inserts ....................................12
4. Using a Mixer’s Master Outputs ................12
AC Power Hookup................................................12
Line Conditioners..................................................13
Program Descriptions
Reverb Effects
Concert Hall Reverb (3 Programs) ......................14
Room Reverb (3 Programs)..................................14
Plate Reverb (2 Programs) ..................................15
Reverb Decay Variations Adjust ..........................15
Pitch-Based Effects
Flange ..................................................................15
Chorus ..................................................................15
Chorus/Reverb......................................................16
Flange/Reverb ......................................................16
Rotary ..................................................................16
Pitch-Based Variations Adjust ..............................16
Delay Effects
Delay ....................................................................17
Delay/Reverb........................................................17
Delay Variations Adjust ........................................17
Tremolo
Tremolo Variations Adjust ....................................17
Troubleshooting Guide ....................................18
Specifications......................................................19
Service ..............................................................Back
Contents
122
DSP 256 — 18-bit Digital Sound Processor
Date of Purchase ________________________________________________________
Dealer’s Name __________________________________________________________
Address ________________________________________________________________
State ________________________________Zip ______________________________
Serial # ________________________________________________________________
Congratulations on your purchase of the DSP 256 - you have purchased one of the
finest compact sound processors on the market today. This unit was developed using the
expertise of professional sound engineers and working musicians. You will find that your
new NADYAUDIO sound processor has superior performance and greater flexibility than
any other sound processor in its price range. Please read this manual carefully to get
the most out of your new unit.
FEATURES
• 16 essential effects programs including
ultra smooth, clean, clear hall, room,
plate and gated reverbs; chorus; flang-
ing; delays; combination chorus/reverb;
and even rotating speaker effects
• Each program offers 16 parameter
adjustments for a total of 256 discrete
effects variations
• Easy to use, the DSP-256 offers input,
output, mix, program and variations
select controls
• 1/4” stereo I/O and bypass (for
footswitch control) connectors
• AC adapter (supplied)
• Housed in a small, rugged, easily
portable, all-metal 1/3 rackspace rack
mountable or tabletop package
• DSP-256 is versatile, affordable and
sounds great - perfect for live perform-
ance, multitrack recording and mix down,
and project studios
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To ensure years of enjoyment from your NADY AUDIO DSP 256 sound processor,
please read and understand this manual thoroughly before using the unit.
INSPECTION
Your DSP 256 was carefully packed at the factory in packaging designed to protect the
units in shipment. Before installing and using your unit, carefully examine the packaging
and all contents for any signs of physical damage that may have occurred in transit.
(Note: Nady Systems is not responsible for shipping damage. If the unit is damaged, do
not return to us, but notify your dealer and the shipping company immediately to make a
claim. Such claims must be made by the consignee in a timely manner.)
CONTENTS:
• Instruction manual
• DSP 256 (verify that the same serial number is same as shown on shipping carton)
• AC Power supply adapter
• Warranty Card
DESKTOP USE
The DSP 256 may be placed anywhere safely as needed where it will not fall or be pos-
sibly damaged. Attach the rubber feet provided to the bottom of the unit if the unit is
placed on a surface you wish to protect from damage.
(Note: The DSP 256 itself doesn’t generate any magnetic or hum fields, but it may pick
up hum or noise from fields generated by power amplifiers. If it does, re-position the unit
to eliminate the noise. Since the DSP 256 adapter may generate hum fields, locate it
away from other audio equipment or wiring as much as possible.)
RACK MOUNTING
The DSP 256 has single rack height, and up to three DSP 256s may be mounted side-
by-side in a standard universal 19” equipment rack available from various rack manufac-
turers or your music dealer. See AC Power Hookup on page 12 for information regard-
ing avoiding grounding problems when rackmounting, if they should arise.
Installation
4
Warning
ATTENTION: RISQUE DE CHOC ELECTRIQUE NE PAS OUVRIR
An equilateral triangle enclosing a lightening flash/arrowhead symbol is
intended to alert the user to the presence of uninsulated “dangerous
voltage”within the product’s enclosure which may be of sufficient
magnitude to constitute a risk of electric shock.
An equilateral triangle enclosing an exclamation point is intended to alert
the user to the presence of important operating and service instructions in
the literature enclosed with this unit.
IMPORTANT SAFETY INSTRUCTIONS
When using this electronic device, basic precautions should always be taken, including the following:
1. Read all instructions before using the product.
2. Do not use this product near water (e.g., near a bathtub, washbowl, kitchen sink, in a wet base-
ment, or near a swimming pool, etc.).
3. This product should be used only with a cart or stand that will keep it level and stable and prevent
wobbling.
4. This product, in combination with headphones or speakers, may be capable of producing sound
levels that could cause permanent hearing loss. Do not operate for a long period of time at a high
volume level or at a level that is uncomfortable. If you experience any hearing loss or ringing in the
ears, you should consult an audiologist.
5. The product should be positioned so that proper ventilation is maintained.
6. The product should be located away from heat sources such as radiators, heat vents, or other
devices (including amplifiers) that produce heat.
7. The product should be connected to a power supply only of the type described in the operating
instructions or as marked on the product. Replace the fuse only with one of the specified type, size,
and correct rating.
8. The power supply cord should: (1) be undamaged, (2) never share an outlet or extension cord
with other devices so that the outlet’s or extension cord’s power rating is exceeded, and (3) never be
left plugged into the outlet when not being used for a long period of time.
9. Care should be taken so that objects do not fall into, and liquids are not spilled through, the
enclosure’s openings.
10. The product should be serviced by qualified service personnel if:
A. The power supply cord or the plug has been damaged.
B. Objects have fallen into, or liquid has been spilled onto the product.
C. The product has been exposed to rain.
D. The product does not appear to operate normally or exhibits a marked change
in performance.
E. The product has been dropped, or the enclosure damaged.
11. Do not attempt to service the product beyond what is described in the user maintenance instruc-
tions. All other servicing should be referred to qualified service personnel.
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(9) Output Level Control
This sets the DSP 256 output level fed to the amplifier or mixer. For optimum signal to
noise and to minimize possible distortion, this control is typically set at 75%, but you can
adjust as needed in your application.
(10) Peak LED
This displays the signal level being processed by the DSP 256. If the signal level is at
overload, this LED will light red continuously and you might begin to hear the signal dis-
tort. Back off the INPUT CONTROL (7) until the LED lights only occasionally.
(11) Power LED
This is lit whenever the DSP 256’s power adapter is plugged in.
(12) Program Select Control
This selects your desired program. The DSP 256 offers 16 preset effects algorithms,
designed for optimum usefulness for any effects applications from guitar setups to studio
recording. To audition these programs, turn the control to scroll through each of the 16
presets.
(13) Variations Select Control
Use this control to edit any of the sixteen DSP 256 programs. Depending on the PRO-
GRAM (12) selected, the function of this control will change. For example, it will adjust
delay length on a Delay program, amplitude modulation rate on the Tremolo program,
etc.
(Note: The VARIATIONS knob is always active. Since the previous setting will remain the
same during program changes, you will need to re-adjust this knob when you change to
a new program.)
6
(8)
(11)
(10)
(7) (9)
(12) (13)
Controls, Connections, and Operation
Front Panel Controls and Use
Before using the DSP 256 it is best to familiarize yourself with the functions of all the
controls and connections. After you have set up your unit in your application, you should
refer back to these descriptions to fully optimize your operation of the DSP 256.
(7) Input Level Control
This sets the level going into the DSP 256. It controls both the Left and Right Input levels
simultaneously. In order to achieve the maximum signal-to-noise ratio, you must properly
set the input and output levels, typically at 75% of full for both the input and output level
controls. This will decrease the possibility of overload distortion and minimize back-
ground noise.
Turn down this control or decrease the volume of the source (instrument, mixer send,
etc.) if the PEAK LED (10) on the DSP 256 lights more than just occasionally. If the con-
nected mixer or amplifier distorts, turn the OUTPUT LEVEL (9) down. For more detail on
level setting, see page 10.
(8) Mix Control
This sets the balance between the direct signal coming into the input and the effects
generated by the DSP 256. Turn the control to the right to hear more effects; turn it to the
left to hear more of the source signal. Keeping this control somewhere in the center will
result in a blend of dry and wet signal. The setting you choose depends on the applica-
tion and desired result. For example, when using the DSP 256 between a guitar and the
guitar amp, the control setting should typically be somewhere in the middle, balancing
the effects with the sound of the source instrument. On the other hand, if the DSP 256 is
connected to a mixing console’s Aux Send, the control should be set all the way to the
right (effects only) so that the balance can be controlled from the board.
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The DSP 256’s LEFT INPUT jack (1) is also normalized internally to the RIGHT INPUT
jack (2), so if you only connect a single mono cable to the LEFT INPUT jack, it will also
be routed to the RIGHT INPUT. However, if anything is connected to the RIGHT jack,
this normalized connection will be broken; in this case the LEFT INPUT jack will feed
only the LEFT INPUT, and the RIGHT INPUT jack feeds only the RIGHT INPUT. Also,
the RIGHT INPUT jack is NOT normalized to the LEFT.
(3) & (4) Output (Left & Right) Jacks
These 1/4”unbalanced phone jacks connect to devices such as the effects returns,
channel inputs or inserts on a mixing console or power amplifier inputs. For mono appli-
cations, use the LEFT (3) output.
8
(3)
(5)
(6) (1) (2)
(4)
Rear Panel Connections and Use
(5) Power Jack
This is a plug for connecting the Nady 9VAC power supply adapter (supplied).
The DSP 256 comes with a power adapter suitable for the voltage of the country it is
shipped to (either 110 or 220V, 50 or 60Hz).
(Note: The correct power supply must be used AT ALL TIMES - any other power supply
might create a fire risk and/or permanently damage your unit. This damage would NOT
be covered under your warranty.)
(6) Bypass Jack
This is a 1/4”phone jack for connecting to an effects bypass footswitch. You can bypass
the effects in two ways, thus allowing the direct signal to pass through the DSP 256
unchanged:
•Turn the MIX (8) control all the way to the left
•Connect a footswitch to this jack and press the footswitch. Each time this footswitch is
pressed, the Bypass mode will turn on and off alternately
(1) & (2) Input (Left/Mono & Right) Jacks
These 1/4”unbalanced phone
jacks connect to sources such as
the effects sends of mixing con-
soles. They may be used with
nominal input levels from -20dBV
(guitar level) to +4dBu.
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3. Using Mixer Inserts
If your mixer has Channel Insert jacks, you can “insert” the DSP 256 in the signal path
of that channel after its input amplifier (and EQ on some mixers) and before its fader.
Consult your mixer manual for understanding the proper way to utilize your DSP256 in
this application. It will also provide the necessary wiring information for connecting your
unit. After you’ve made the proper connection, set the desired “wet/dry” balance using
the DSP 256’s MIX (8) control. The INPUT (7) and OUTPUT (9) controls of the DSP 256
should be set for unity gain so that the volume remains approximately the same when
the Insert jack is either plugged in or removed from the mixer.
4. Using a Mixer’s Master Outputs
If you want to add effects to everything on the mixer, connect the DSP 256 between the
mixer’s outputs and the amplifier’s or recording machine’s input. Connect the Left and
Right Master Outputs of the mixer to the LEFT/MONO (1) and RIGHT (2) inputs of the
DSP 256. Then connect the LEFT (3) and RIGHT (4) outputs of the DSP 256 to a stereo
amplifier or to two input channels of another mixer (for sub-mixing applications).
AC Power Hookup
After making your connections, follow this procedure:
1. Before turning on the DSP 256 power, check that:
• All connections have been made correctly
• The volume controls of the amplifier or mixer are turned down
LEFT INPUT
INSERT LEFT OUTPUT
LEFT LEFT OUTPUT
Power Amp
13
2. The DSP 256 comes with a power adapter suitable for the voltage of the country it is
shipped to (either 110 or 220V, 50 or 60Hz). Insert the Power Supply Adapter into the
9VAC (5) input on the rear panel of the DSP 256 and plug the adapter into an AC outlet.
The Power On LED (11) will illuminate, and the unit is ready for operation.
3. Turn on the power of the connected amplifier or mixer and adjust their settings as nec-
essary.
(Note: Nady Systems, Inc. cannot be responsible for problems caused by using the DSP
256 or any associated equipment with improper AC wiring or voltage.)
(Note: The DSP 256 has no need for safety grounding as it has no power supply ground.
It is powered by an external low-voltage adapter with an internal transformer isolated for
safety. As with most unbalanced equipment, signal ground is connected to chassis
ground at the input and output jacks. Be aware that if you rackmount the DSP 256 with
metal rack railing it would share a common ground with the other equipment in the same
rack. If you develop hum or noise problems with this unit, you should switch to non-con-
ductive rack rails or rack isolators to avoid ground loops.)
Line Conditioners
Although the DSP 256 is designed to tolerate typical voltage variations, the AC line may
contain spikes or transients that can possibly stress your gear and, over time, cause a
failure. The Nady Audio PCL-800/810/815 Power Line Conditioners offer advanced filter-
ing and are the most cost effective way to ensure quietest operation of your DSP 256.
DSP256manual 11/9/01 10:18 AM Page 12

Plate Reverb (2 Programs)
This algorithm simulates a classic echo plate, typically a 4’by 8’suspended sheet of
metal with transducers at either end popularly used in the 70’s to produce reverb. Its
lush, transparency is ideal for the classic rock sound, especially on vocals, guitars and
piano.
• Plate 1 - A classic plate bright reverb sound particularly suited for vocals.
• Plate 2 - A warmer reverb-ideal for adding sustain on strings and acoustic guitar.
Reverb Decay Variations Adjust
The reverb decay determines how long the reverb will sound before it dies away. A
longer reverb decay simulates an increased room size. High-energy dance and rock
music usually use shorter decays, and jazz, ballads, and classical music generally utilize
longer reverb decays.
Pitched-Based Effects (5 Programs)
The DSP 256 can produce layered sounds that are far more complex than the input sig-
nal by altering its pitch and delay characteristics in several different ways. For example,
the signal can be split into two parts, the pitch of one altered and then the two mixed
back together so that the effect results from the difference between the dry original and
the wet effects signals. Generally it’s advisable to start such effect mixes at equal
strengths for these two signals by setting, for example, the MIX (8) control at 50% for
the DSP 256 on an instrument setup, or raising the effects return on a mixer.
• Flange - Flanging was originally done by intermittent-
ly slowing down one of two tape machines by applying
hand pressure against the flanges of the tape supply
reels both playing the same program in synchroniza-
tion. This resulted in the characteristic flanging “jet air-
plane”sound caused by varying phase cancellations
occurring at different frequencies. The flanging pro-
duced by the DSP 256 is specially intensified by split-
ting the signal into four parts with a stereo dry signal
and a separate delay section for both left and right
channels with one channel flanging up while the other
channel flanges down.
• Chorus - Chorusing is similar to flanging, but modu-
lates the delayed signal over a much longer delay
1514
Program Descriptions
Reverb Effects (8 Programs)
Reverb consists of a variety of distinct echoes (reflections), each of different delay
length. Over time, each echo’s amplitude and timbre
decays according to the unique characteristics of the
acoustic space, such as sound location, distance and
reflectivity of the walls and numerous other factors. The
result is that there are many types of reverb, each with
its own sound. The following types of reverberation are
available with the DSP 256:
Concert Hall Reverb (3 Programs)
This algorithm simulates large concert halls, which are
typically large rooms with many reflective surfaces. The
complex echoes produced sound rich with a very
noticeable change in timbre as the reverb decays. A
classic versatile reverb, the Concert Hall programs
sound good on vocals, drums, and acoustic, orchestral, and electric instruments.
• Hall 1 - A large, bright hall program specially suited for vocals, guitars or drums
• Hall 2 - A warmer hall program. Select a long delay for added depth and character with
acoustic guitars and pianos.
• Hall 3 - This medium-sized hall program features a 12ms pre-delay before the reverb
starts-perfect for that extra big rock snare drum, but also great on electric guitar and all
vocals.
Room Reverb (3 Programs)
Offering the sound of a medium-size studio room, this algorithm has a bigger sound than
a hall reverb, with added punch perfect for both rock and dance music. With reflective
attack and smooth decay, the rich sound of this reverb is ideal for keyboards, drums and
guitars.
• Room 1- This reverb simulates a highly reflective studio room with a pronounced early
reflection slap-ideal for making drums sound big and enhancing acoustic instruments,
especially with the decay turned up.
• Room 2- This program is ideal on the studio for livening up dry tracks such as synths
or acoustic mixes.
• Room 3- Simulating a warm studio room, this program is perfect for acoustic guitars
and classical instruments.
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range (typically >12 ms). In addition, the signal is split
into four parts with a dry signal and a separate detun-
ing section for both left and right channels that is
modulated by an LFO (low frequency oscillator) that
causes the detuning to vary, further increasing the
chorus effect. The DSP 256’s chorus produces a
wider stereo image than regular stereo choruses
because it is a “true”stereo chorus with individual
LFOs , set to vary differently, controlling the left and
right sides. This results in a constant chorus rate dif-
ference between the left and right sides, and thus,
because the chorus processes the left and right sides
individually, the stereo imaging will be maintained.
• Chorus/Rev - This multi-effect program combines stereo chorus with a large room
reverb.
• Flange/Rev - This multi-effects program offers a layered stereo flange/large room
reverb. Both Chorus/Rev and Flange/Rev are ideal for keyboards such as synths and
electric pianos as well as guitars.
• Rotary - The Rotary effect simulates rotating speakers originally used during the 60’s
with both organs and guitars to produce the unique “Lezlie”sound, characterized by
multi-layered tonal timbre changes. The rotary effect produced by the DSP 256 sounds
authentic and with speed changes will slowly ramp to the new speed rather than change
abruptly, just as the Lezlie would do mechanically.
(Note: Always turn the Variations control all the way to the right when using the Rotary
program.)
Pitch-Based Variations Adjust
On the chorus and flange programs, the VARIATIONS CONTROL (13) functions as a
rate adjust, setting the speed of the chorus or flanging sweep. Increasing the chorus rate
simultaneously decreases the depth, thus maintaining a constant pitch shift. On the
Rotary program, the VARIATIONS CONTROL (13) adjusts the speed of the Leslie motor.
On the Flange/Rev and Chorus/Rev programs, the VARIATIONS CONTROL (13) edits
the reverb decay time.
17
Delay Effects (2 Programs)
Delay is often utilized to add a depth to sound that is cleaner than that offered by reverb
effects. Whereas reverb consists of numerous echoes of varying length, which can color
sound, delay is purer and less “muddy”as it only has a distinct reflection repeat.
• Delay - This program provides a delay of up to 1000 ms.which can be adjusted in
terms of delay and decay times. It is great for adding clean “space”effect to vocals and
instruments.
• Delay/Rev -This program combines a room reverb with different delay presets.
Delay Variations Adjust
For the delay programs the VARIATIONS CONTROL (13) sets the time between the
input signal and the first delay tap.
Tremolo (1 Program)
Tremolo is a long-popular effect for enhancing sustained electric piano or guitar chords,
much like natural vocal vibrato. It is produced by amplitude modulating the signal.
• Tremolo - This program is normally used 100% “wet”so that the direct sound does not
“cover”the amplitude modulation of the tremolo.
Tremolo Variations Adjust
For the tremolo program the VARIATIONS CONTROL(13) sets the amplitude modula-
tion rate.
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Troubleshooting Guide
If you experience problems while operating the DSP 256, please use the following
table to locate possible causes and solutions before contacting Nady Service
Department for assistance.
The Power LED does not light
when the unit is powered on.
Unit does not respond to front
panel controls.
Hum or noise from output.
No audio.
Noisy sound.
Distorted sound, Peak LED lit.
No power.
Unknown
Ground loop, unshielded
cables.
Bypass function is on with Mix
turned 100% wet.
Too low output level.
Too low input level.
Too low output level and Aux
Return on mixer is up full.
Too high input level.
Check that the power cable is
plugged in properly.
Power down and power up
again.
Try different power outlet or
different audio cables.
Turn the Mix control to the left
or press the Bypass
Footswitch.
Turn the Output control to the
right.
Turn up the Input Level con-
trol.
Turn Output up and reduce
Aux Retrun level on mixer.
Turn down the Input
Level control.
SYMPTOM CAUSE SOLUTION
19
Specifications
SYSTEM PERFORMANCE
Frequency Response................................................................................ ±2dB from 20 Hz to 20 KHz
Signal-to-Noise Ratio..............................................................................>82dB linear, 20 Hz - 22 KHz
Distortion.................................................................................................... <0.01% @ 1 KHz (-10dBV)
Crosswalk.......................................................................................................... <90dB below full scale
INPUT
Number of Channels............................................................................................................................2
Format..........................................................................................................................1/4”unbalanced
Sensitivity ..................................................................................................................................-10dBV
Maximum Level ........................................................................................................................+10dBV
Impedance ......................................................................1M Ω/channel stereo, 500K ?/channel mono
A/D - D/A CONVERSIONS
A/D converter ..........................................................................................................18-bit Sigma-Delta
D/A converter............................................................................................................18-bit Sigma-Delta
OUTPUT
Number of Channels............................................................................................................................2
Format..........................................................................................................................1/4”unbalanced
Maximum Level......................................................................................................................+11.5 dBu
Output Impedance...................................................................................................................... <500Ω
FRONT PANEL
Controls ..................................................................INPUT, MIX, OUTPUT, PROGRAM, VARIATIONS
Indicators ..........................................................................................................Power LED, Peak LED
REAR PANEL
Input (LEFT/MONO, RIGHT) ......................................................................................1/4”2-conductor
Output (LEFT, RIGHT) ................................................................................................1/4”2-conductor
BYPASS..........................1/4”1-conductor (accepts normally open/closed) (Momentary footswitches)
Power ........................................................................................AC 9 Volt Power Transformer Adapter
EFFECTS
Processor Speed ..............................................................12.5 MIPs (million instructions per second)
Internal processing resolution ..................................................................................52-bit accumulator
Factory Present Programs (ROM) ....................................................................................................16
Factory Variations for each Present Program (ROM) ........................................................................16
Delay memory ..........................................................................................................3000 milliseconds
Reverb effects..............................................................................................Concert Hall, Room, Plate
Delay effects ....................................................................................................Mono Delay, Delay/Rev
Pitch effects ..........Stereo Tremolo, Stereo Chorus, Stereo Flange, Flange/Rev, Chorus/Rev, Rotary
SIZE
Dimensions ................................................................................5.2”x 4.6”x 1.7”(131 x 116 x 44mm)
Weight ..............................................................................................................................3 lbs (0.90 g)
The specifications above are correct at the time of printing of this manual. For improvement purposes, all specifications
for this unit, including design and appearance, are subject to change without prior notice.
DSP256manual 11/9/01 10:18 AM Page 18

NADY SYSTEMS, INC. • 6701 SHELLMOUND STREET, EMERYVILLE, CA 94608
Tel: [phone] • Fax: [phone] • www.nadywireless.com
SERVICE FOR YOUR NADY AUDIO PRODUCT
(U.S.) Should your NADY AUDIO product require service, please contact the
Nady Service Department via telephone at [phone], or e-mail at
[email protected].
(International) For service, please contact the NADY AUDIO distributor in your
country through the dealer from whom you purchased this product.
DO NOT ATTEMPT TO SERVICE THIS UNIT
YOURSELF AS IT CAN BE DANGEROUS AND
WILL ALSO VOID THE WARRANTY.
DSP256manual 11/9/01 10:18 AM Page 20