Spectral Audio Neptune II Owner's Manual

Owner's Manual

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Contents

1 Introduction ...............................................................................................................................................2

2 Environment care......................................................................................................................................2

3 Neptune II .................................................................................................................................................2

4 Performance and Signals of Neptune II:...................................................................................................3

5 Operating and safety instructions .............................................................................................................4

6 Guarantee................................................................................................................................................. 4

7 Operational and functional description......................................................................................................5

7.1 The Neptune II Signal Flow: ..............................................................................................................6

7.2 Subtractive Synthesis (Theory)..........................................................................................................7

8 Initial Start-up............................................................................................................................................ 7

8.1 Using the external audio input ...........................................................................................................7

8.2 Technical data of the CV and GATE In- / Output ..............................................................................7

9 Trouble-shooting / FAQ............................................................................................................................. 8

10 MIDI Functions ......................................................................................................................................8

10.1 Normal operating mode .....................................................................................................................8

10.2 Learn mode........................................................................................................................................ 9

10.2.1

Note-On Command (key is pressed): .....................................................................................9

10.2.2

Program Change Command:.................................................................................................. 9

10.3 Re-trigger...........................................................................................................................................9

10.4 Filter Dynamic Operation................................................................................................................... 9

10.5 Filter Velocity mode ......................................................................................................................... 10

10.6 Aftertouch to Cutoff..........................................................................................................................10

10.7 Aftertouch to Modulation..................................................................................................................10

11 Possible manual changes ...................................................................................................................10

12 Notes................................................................................................................................................... 10

12.1 Service via Internet.......................................................................................................................... 10

13 MIDI Implementation Chart .................................................................................................................11

14 Technical Data Neptune II...................................................................................................................12

15 Neptune II Sounds............................................................................................................................... 12

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1 Introduction

Thank you very much for buying the Neptune II Analogue Synthesizer.
The Neptune II is a purely analog synthesizer with MIDI and CV control. It offers special features and is simple to

use because it has a button or switch for each parameter.
The audio input enables processing of external signals.
In order to use the Neptune II professionally, we recommend that the following chapters are read carefully.
We wish you much pleasure and many successful productions using the Neptune II!

This manual has been produced with the greatest care. Spectral Audio is nevertheless unable to accept any
responsibility for errors or omissions. Reproduction is permitted only with the consent of the manufacturer.

2 Environment care

The Neptune II is made as environmentally friendly as possible. This was a very important consideration in the
design process. Specifically, this means that:

- the pads for the electronic components are as small as possible to save paste and solder

- the bottom casing is recyclable normal metal sheet

- the front panel and the lid are recyclable normal aluminum

- it is easy to disassemble

- the package materials are recyclable

3 Neptune II

With the Neptune II, the original Neptune has been improved and carries several internal and general
improvements. The Neptune II benefits from these changes:

- significantly improved quality smooth potentiometers

- tactile soft touch knobs

- high efficiency 5mm LEDs

- 2.2mm travel push switches for better visual feedback

- key follow switch, volume potentiometer and power on switch have been added

- free-run switch to have Oscillator 3 free of tracking the keyboard

- improved true noise generator with a spectrum now up to 100kHz

- several possibilities for additional operations via manual internal changes

The Neptune II shares these design features with the original Neptune:

- pure DC Design means no capacitors in the signal flow

- low noise design

- high quality cascade filter

- true noise generator (not digital noise)

- MIDI regeneration - incoming MIDI signal is internally regenerated to MIDI Thru, not just amplified.

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4 Performance and Signals of Neptune II:

Sawtooth at 250Hz:

Sawtooth Spectrum:

all three VCOs provide the same excellent signal quality

Noise:

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Noise Spectrum: 20Hz..20kHz

5 Operating and safety instructions

The instrument is intended only for the form of use described in this operating manual. It is to be used in dry
rooms only. Do not allow any liquids to enter the instrument. Should this happen, the instrument requires
cleaning by a specialist.

Use only the original PSU (15VAC, 500mA).
Do not expose the instrument to direct sunlight. Do not use the instrument in the vicinity of a heater or any other

source of heat. Do not expose the instrument to temperatures above 50°C (degrees Celsius) or below 10°C.
The minimum operating temperature is 10°C. Handle the instrument with due care when transporting.

Use only the original packing when returning the instrument to our company for guarantee service, software
updating, repair work, etc. Other forms of delivery will not be accepted due to the danger of damage caused in
transit. Please make sure you retain the packing container and inner packing materials for such purposes.

6 Guarantee

A one year guarantee period from the date of purchase applies for manufacturing defects. Should the instrument
be interfered with or abused in any way, the guarantee coverage will cease immediately.