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Tested To Comply With FCC Standards FOR OFFICE USE This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference and (2) this device must accept any interference received, including interference that...
Quick Start Thanks for purchasing your Tetra synthesizer! Listen to the sounds, twiddle some knobs, have some fun! Please Register! Please go to www.davesmithinstruments.com and register your synth. If you purchased directly from us, there is no need to register — we already have your contact information.
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decrement change the values. These settings are remembered when the synth is turned off. Summary You should be up and running now; for more operation information, read on. Or, just look up specific parameters for detailed notes. Pages 41 through 43 contain a handy reference for mod destinations and sources.
Getting Connected Tetra has several inputs and outputs on its back panel. Connect the power supply included with your Tetra. The power Power Input — supply comes with different AC adaptor prongs that allow it to work anywhere in the world. If for whatever reason you need to use a different supply, it must match the specifications printed on the front panel.
Front Panel Controls Use S to change and scroll through programs and combos. Select — ELECT When A is on, S changes the value of the current SSIGN ARAMS ELECT parameter. Also used to select parameters in Global mode. Tetra has four modes of operation: Mode (Program/Combo/Global) —...
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Use W to save an edited program or combo to any of Tetra’s Write — RITE memory locations. To execute the write operation, press the increment (+) button. To store a program or combo in a different location, press the W button and RITE change the destination using the S...
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Alternately, with A on, choose a parameter to edit with any SSIGN ARAMETERS of the A controls, and change the parameter’s value SSIGNABLE ARAMETERS using S or the increment (+) or decrement (-) buttons. ELECT — This button behaves differently depending upon the current Edit B/Combo mode.
Basic Operation Tetra has multiple personalities. It is a four-voice, analog poly synth, a sort of “mini Prophet.” But the voice architecture is based on Mopho, so it has a couple of sonic tricks up its sleeve—specifically sub-octave generators and feedback— that are absent from the Prophet.
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Combos When in Program Mode, press the Mode switch to enter Combo Mode. Combos are combinations of four programs, one for each voice. In Combo Mode, use and increment/decrement to change combos. Each of the A ELECT SSIGNABLE knobs controls a parameter for its respective voice: knob 1 for ARAMETERS voice 1, knob 2 for voice 2, and so on.
Global Parameters Tetra’s Global parameters affect all programs globally. Examples include MIDI channel and fine tune. To edit the Global parameters, hold down the Mode switch (Program/Combo/Global) until the G LED lights. The S LOBAL ELECT knob changes the global parameter and the increment and decrement buttons change the value.
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When On, the synth will respond to received MIDI MIDI SysEx: Off, On — SysEx messages, and will transmit them, when prompted, to the MIDI Out. See Sysex Messages on page 62 for details. MIDI Out can be switched to MIDI Thru to MIDI Out Select: Out, Thru —...
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Note: Outputs 3 and 4 are noticeably louder than the other two outputs. This is normal. Outputs 3 and 4 are always monophonic and, therefore, do not require as much headroom as the mix outputs, which have to accommodate up to four voices at one time without distorting. The higher level provides optimum signal-to-noise ratio.
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Tetra does not have a full hardware reset, but select this Reset Globals — parameter and press W to reset the global parameters to their factory RITE defaults. Allows dumping of programs and combos in MIDI SysEx Dump: see table — SysEx format via MIDI.
Program Parameters All Program parameters can be edited using any of A SSIGNABLE ARAMETERS controls. To assign a parameter to a control, press the A SSIGN ARAMETERS button to light the LED, and then turn any of the knobs (1 through 4) to select a parameter.
Display Waveshape No output Osc Off Sawtooth Sawtooth Triangle Triangle Sawtooth — Triangle mix Saw-Tri Pulse Wave, with pulse width ranging from minimum Pulse xx (0) to maximum (99). The pulse width will turn off at the two extremes — this allows some interesting modulation possibilities.
accurate sounds, and allows precise de-tuning. The Oscillator Slop parameter allows subtle amounts of frequency drift. For larger amounts, use a random LFO or white noise mod. Sets the bend range, in semitones, of the pitch Pitch Wheel Range: 0…12 — wheel.
Controls the amount of audio from Oscillator 1 used to Audio Mod: 0...127 — modulate the filter cutoff frequency. For filter-only audio, set O SCILLATOR to 127, O to Off, and O to the desired SCILLATOR HAPE SCILLATOR HAPE waveshape. This is useful for bell-like FM sounds. A wide range of sounds can also be made using A with the oscillators routed normally through the UDIO...
Sets the Decay time. Decay: 0…127 — Sets the Sustain level. Sustain: 0…127 — Sets the Release time. Release: 0…127 — There is a pan circuit after the VCA that pans the audio Pan Spread: 0…127 — in the stereo field individually per voice. With a Pan Spread of 0, all four voices are panned dead center.
Display Timing Sync Sequence speed divided by 3 3 Steps Sequence speed divided by 2 2 Steps Sequence speed divided by 1.5 1.5 Step One cycle per step 1 Step Two cycles every three steps 2/3 Step Two cycles per step 1/2 Step Three cycles per step 1/3 Step...
Sets a delay between the time Envelope 3 is triggered and Env Delay: 0…127 — when the Attack portion actually begins. Sets the Attack time of Envelope 3. Env Attack: 0…127 — Sets the Decay time. Env Decay: 0…127 — Sets the Sustain level.
Selects the destination to which the mod wheel is Mod Wheel Destination — routed. See Modulation Destinations on page 39 for a list of possible destinations. Sets the maximum amount of modulation that Press Amount: -127…+127 — can be applied from MIDI Channel Pressure (aftertouch). Selects the destination to which the Channel Pressure is Press Destination —...
Determines how Tetra responds to keyed notes Unison Assign: see table — when unison is on. Display Key mode Low note priority Low Note Low note priority, re-trigger envelopes LowRetrig High note priority HighNote High note priority, re-trigger envelopes HighRetrg Last note hit priority LastNote Last note hit priority, re-trigger envelopes...
For Stack, both layers respond to MIDI notes for the entire key range, enabling two patches to be played simultaneously with a single key stroke. Voices 1 and 2 are assigned to layer A, 3 and 4 are assigned to layer B. Split assigns layer A from the lowest note to below the split point (see previous parameter) and layer B from the split point to the highest note.
Sets the order in which the arpeggiator plays notes. Mode: see table — Mode Behavior Plays from lowest to highest note. Plays from highest to lowest note. Down Plays from lowest to highest and back to lowest. Up Down Plays notes in the order keys were pressed. Assign Randomly plays notes.
Display Trigger mode Striking a key advances the sequencer Key Step one step. Turns the sequencer on and off. On/Off: Off, On — Sets the destination for each of the four Seq 1, 2, 3, or 4 Destinations — sequence tracks. For a complete list, see Modulation Destinations on page 41. Sets each step value Seq 1, 2, 3, or 4 Steps: C0…D5+ or 0…125, Reset, Rest —...
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For the most part, the sequence destinations are the same as the modulation destinations, which is appropriate: a sequence is just another modulation source. For each sequence step, the envelopes are gated on for half the step’s duration. The duration varies according to the BPM and Clock Divide settings (or the MIDI clock, if synced to an external source).
Sequences do not have to be the same length, however, which makes for some very interesting, less repetitive patterns, particularly when sequences are set to odd and even numbers of steps. Steps 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Dest.
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three routed to filter resonance, and sequence four routed to amplifier envelope amount for accents. Many of the factory programs have sequences programmed, so you can refer to those to see how certain effects are being achieved. To program a sequence: 1.
oscillator frequency to glide from the step three value when step four is gated on. The higher the Slew value, the slower the slew rate. And the slew rate can be different for each step. But its not just for oscillator glide. Slew can be applied to any of the destinations.
Combos A combo is a collection of four programs—one per voice—combined to make a sort of super program. How a combo responds to MIDI note data depends largely upon whether or not it is monophonic (that is, unison is on) or polyphonic.
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The top row shows the current combo, the program, the bank, and the voice being edited. The bottom row shows the program name. Note: Though the other combos and program banks can be used as a starting point for building new combos, the actual programs used are copies, so any edits made in Combo Mode do not affect the source programs.
voices 2 through 4), the combo will play back polyphonically. If the P button is to be used to latch notes on, Push It Mode must be set to Toggle in each of the voices. To start playback of four sequences simultaneously from the button, set Unison to On in voice 1, set the Push It Mode to Toggle for all four voices, and make sure Sequencer is set to On for all four voices.
Using Poly Chain Poly Chain enables multiple Tetras to be chained together for increased polyphony, up to 16 voices. MIDI note data from a keyboard, sequencer, or other controller is intelligently processed so that, when one synth’s maximum polyphony is reached, additional notes are passed through the Poly Chain Out jack and routed to another synth.
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Also, Mopho’s I (similar to Tetra’s F ) is not NPUT EEDBACK programmable, so it may take some tweaking to get feedback to sound the same on Mopho and Tetra, even if the same programs are loaded in both. Programs that don’t use feedback should sound the same.
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Various Poly Chain Configurations Using Tetra, Mopho, and the Prophet ’08* *If Out 4 and Out 8 do not appear as poly chain options on the Prophet, contact support@davesmithinstruments.com for information about updating the OS.
Using USB Tetra’s USB 2.0 port enables bidirectional MIDI communication with a computer. A MIDI interface and MIDI cables are not necessary, just a USB cable. Tetra is a Class Compliant USB device. That means it does not require any additional drivers to be installed to communicate with a Mac or Windows computer.
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Windows Vista essentially behaves the same as XP, but the device name is DSI Tetra rather than USB Audio Device. In Windows, if you unplug the USB cable and plug it back in while a program has the Tetra port open, you may have to resync. That usually means going to the USB Audio Device (or DSI Tetra) Properties, as in the procedure above, and clicking OK.
Modulation Destinations Display Destination No destination selected Oscillator 1 Frequency Osc 1 Freq Oscillator 2 Frequency Osc 2 Freq Oscillator 1 and 2 Frequency OscAllFreq Oscillator Mix Osc Mix Noise Level NoiseLevel Oscillator 1 Pulse Width Osc1 PulsW Oscillator 2 Pulse Width Osc2 PulsW All Oscillators Pulse Width Osc All PW...
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Envelope 3 Release Rate Env3Releas All Envelope Release Rates EnvAll Rel Modulator 1 Amount Mod 1 Amt Modulator 2 Amount Mod 2 Amt Modulator 3 Amount Mod 3 Amt Modulator 4 Amount Mod 4 Amt Feedback Volume Fback Vol Sub Oscillator 1 Level Sub Osc 1 Sub Oscillator 2 Level Sub Osc 2...
Parameter List Osc 1 Frequency VCA Env Release Mod 3 Amount Osc 1 Fine Freq Pan Spread Mod 3 Destination Oscillator 1 Shape Program Volume Mod 4 Source Oscillator 1 Glide LFO 1 Frequency Mod 4 Amount Osc 1 Key Track LFO 1 Shape Mod 4 Destination Sub Osc 1 Level...
Support Troubleshooting Here are a few suggestions for resolving problems that may occur. The sequencer has stopped running. Make sure Clock in the Global menu is set to Internal. Some of the programs sound different. Check the Mod Wheel position. The Mod Wheel can do a lot more than just add vibrato.
Please contact support@davesmithinstruments.com to determine the best course of action for getting your Tetra repaired. For your own protection, as well as ours, please do not return any product to Dave Smith Instruments without a return authorization (RA) number. To issue an RA number, Technical Support needs: •...
MIDI Implementation Tetra receives MIDI data according to the mode controls under G . In LOBAL addition, there is interaction between some of the program parameters that determine the overall response of Tetra to MIDI data. Note that the following applies to using both the MIDI jacks and USB.
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Received Channel Messages Status Second Third Description 1000 nnnn 0kkkkkkk 0vvvvvvv Note Off. Velocity is ignored 1001 nnnn 0kkkkkkk 0vvvvvvv Note On. Note off if vvvvvvv = 0 1010 nnnn 0kkkkkkk 0vvvvvvv Polyphonic Key Pressure 1011 nnnn 0vvvvvvv 0vvvvvvv Control Change; see “Received Controller Messages”...
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Transmitted Controller Messages Status Second Third Description 1011 nnnn 0000 0111 0vvvvvvv Volume knob 1011 nnnn 0010 0000 0vvvvvvv Bank Select — 0 to 2 See sections below for additional Continuous Controller (CC) and Non- registered Parameter Number (NRPN) messages transmitted. Additional Continuous Controllers (CCs) Transmitted/Received The following table details how CCs are mapped onto Tetra’s controls.
NRPN Messages The Non-Registered Parameter Number (NRPN) MIDI messages are used to transmit and receive both global and program parameters. They are transmitted when MIDI Parameter Send is set to NRPN in Global, and received when MIDI Parameter Receive is set to either NRPN or All in Global. The messages are handled in standard MIDI format using the NRPN CC commands in running status byte format.
Received NRPN Messages Status Second Third Description 1011 nnnn 0110 0011 0vvvvvvv NRPN parameter number MSB CC 1011 nnnn 0110 0010 0vvvvvvv NRPN parameter number LSB CC 1011 nnnn 0000 0110 0vvvvvvv NRPN parameter value MSB CC 1011 nnnn 0010 0110 0vvvvvvv NRPN parameter value LSB CC 1011 nnnn...
The following tables list the values used with the program parameters to specify modulation destinations and sources. Mod Destinations Value Env 2 Release Env 3 Release Osc 1 Freq All Env Releases Osc 2 Freq Mod 1 Amt Osc 1 and 2 Freq Mod 2 Amt Osc Mix Mod 3 Amt...
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Note: In Multi Mode, the regular, program NRPNs are received and transmitted for each of the four voices on their separate MIDI channels. Quad NRPNs come from/go to all four voices in a combo. Parm Parameter Quad OSC 1 FREQ 1024 1280 1536...
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VCA ENV VEL 1055 1311 1567 VCA DEL 1056 1312 1568 VCA ATT 1057 1313 1569 VCA DEC 1058 1314 1570 VCA SUS 1059 1315 1571 VCA REL 1060 1316 1572 LFO 1 FREQ 1061 1317 1573 LFO 1 SHAPE 1062 1318 1574...
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MOD SOURCE 3 1095 1351 1607 MOD AMT 3 1096 1352 1608 MOD DEST 3 1097 1353 1609 MOD SOURCE 4 1098 1354 1610 MOD AMT 4 1099 1355 1611 MOD DEST 4 1100 1356 1612 SEQ 1 DEST 1101 1357 1613 SEQ 2 DEST...
PARAM ENC SEL V4 FEEDBACK 1134 1390 1646 GAIN PUSH IT NOTE 1135 1391 1647 PUSH IT 1136 1392 1648 VELOCITY PUSH IT MODE 1137 1393 1649 SUB OSC 1 VOL 1138 1394 1650 SUB OSC 2 VOL 1139 1395 1651 FEEDBACK VOL 1140...
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0vvv vvvv If MIDI Channel = ALL, 0vvvvvvv = 0111 1111. Otherwise 0vvvvvvv = Channel Number 0-15. 0000 0110 Inquiry Message 0000 0010 Inquiry Reply 0000 0001 DSI ID 0010 0110 Tetra ID (Family LS) 0000 0001 Family MS 0000 0000 Family Member LS 0000 0000 Family Member MS...
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Request Global Parameter Dump Status Description 1111 0000 System Exclusive (SysEx) 0000 0001 DSI ID 0010 0110 Tetra ID 0000 1110 Request Global Parameter Transmit 1111 0111 End of Exclusive (EOX) Tetra will respond by sending out the current values of Global Parameters in the format described below in Global Parameters Data Dump.
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Program Data Dump Status Description 1111 0000 System Exclusive (SysEx) 0000 0001 DSI ID 0010 0110 Tetra ID 0000 0010 Program Data 0000 00vv Bank Number, 0 - 3 0vvv vvvv Program Number, 0 - 127 0vvv vvvv 384 bytes expanded to 446 MIDI bytes in “packed MS bit” format (see page 66.) 1111 0111 End of Exclusive (EOX)
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Combo Edit Buffer Data Dump Status Description 1111 0000 System Exclusive (SysEx) 0000 0001 DSI ID 0010 0110 Tetra ID 0011 0111 Edit Buffer Data 0vvv vvvv 1024 bytes expanded to 1177 MIDI bytes in “packed MS bit” format (see page 66.) 1111 0111 End of Exclusive (EOX) Global Parameters Data Dump...
Mode Change: Combo Mode Status Description 1111 0000 System Exclusive (SysEx) 0000 0001 DSI ID 0010 0110 Tetra ID 0011 0001 Select Combo Mode 1111 0111 End of Exclusive (EOX) Packed Data Format Data is packed in 8 byte “packets”, with the MS bit stripped from 7 parameter bytes, and packed into an eighth byte, which is sent at the start of the 8 byte packet.
Hidden Functions Hold the A switch and hit the Mode switch to calibrate the SSIGN ARAMETERS low-pass filter and analog oscillator waveshapes. This should not be necessary for normal operation.
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