Arturia Minimoog V manual

USER’S MANUAL version 1.0[...]

Programming: Nicolas Bronnec Pierre-Jean Camilieri Sylvain Gubian Xavier Oudin Gilles Pommereuil Cédric Rossy Graphics: Yannick Bonnefoy (Beautifulscreen) Thomas & Wolfgang Merkle ( Bitplant) Manual: Jean-Michel Blanch et Houston Haynes Tom Healy Xavier Oudin Gilles Pommereuil David Poncet Mitsuru Sakaue Sound Designers : Jean-Michel Blanch et[...]

TABLE OF CONTENTS 1 INSTALLATION 1.1 Windows 5 1.2 Mac OS X 7 1.3 Mac OS 9 8 2 QUICK START 2 . 1 U s i n g t h e p r e s e t s 1 0 2 . 2 T h e p l a y i n g m o d e s 1 3 2.3 Overview of the «Close» mode 14 2 . 4 T h e « O p e n » m o d e 1 5 2.4.1 The modulation matrix 16 2 . 4 . 2 T h e L F O 1 6 2 . 5 T h e a r p e g g i a t o r s e c t i o [...]

5 THE BASICS OF SUBTRACTIVE SYNTHESIS 5.1 The 3 main elements 37 5.1.1 The oscillator 37 5 . 1 . 2 T h e f i l t e r 4 1 5 . 1 . 3 T h e a m p l i f i e r 4 3 5 . 2 O t h e r m o d u l e s 4 3 5 . 2 . 1 T h e k e y b o a r d 4 3 5.2.2 The envelope generator 44 5.2.3 The low frequency oscillator 4 4 6 QUELQUES ELEMENTS DE DESIGN SONORE 6.1 Subtracti[...]

AR TURIA – minimoog V – USER’S MA NUAL 5 1 INSTALLATION 1.1 WINDOWS INSTALLATION (WIN9X, M E , 2000, XP) Insert the CD-ROM into the dr ive. Explore the contents of the C D-ROM, double click on the icon named «minimoog V Set up PC.exe» At the first step of the installation, choos e the destination folder for the minimoog V installation. By d[...]

AR TURIA – minimoog V – USER’S MA NUAL 6 Choice of protocols For the VST and RTAS protocols, you must choos e an installation folder in order for the host application to use the minimoog V as a pl ug-in. If you do not know how to make this choice, go to chapter 8. Choice of VST plug-in installation folder The installation program now has enou[...]

AR TURIA – minimoog V – USER’S MA NUAL 7 1.2 MAC OS X INSTALLATION Insert the CD-ROM into the dr ive. Explore the contents of the C D-ROM, double click on the icon named «minimoog V Setu p Mac». Enter the administrator name and password of your computer in the authentication window. Authentication window The minimoog V will next be in stall[...]

AR TURIA – minimoog V – USER’S MA NUAL 8 Next, have your license number ready and enter it with your fi rst and last names in the user information window. The installation program now has enough informat ion to complete the installation. In a few seconds, you w ill be able to use the minimoog V. 1.3 MAC OS 9 INSTALLATION Insert the CD-ROM int[...]

AR TURIA – minimoog V – USER’S MA NUAL 9 User information window The installation program can au tomatically dete ct folders containing VST plug-ins on your computer. Auto detection of VST folders Choose the applications f or which you wish t o install the minimoog V as a VST plug- in. Choice of VST applications For each of the selected appli[...]

AR TURIA – minimoog V – USER’S MA NUAL 10 2 QUICK START This chapter w ill help you get to know the main aspects of how the minimoog V work s. You will be presented an ov erview of the different parts of the synthesiz er while using the program for the first time. You will find a detailed description of all visible settings and controllers in[...]

AR TURIA – minimoog V – USER’S MA NUAL 11 Select the preset JMB_Classic1 The minimoog V comes with 400 presets, whic h will familiarize you with the sounds of the synthesizer. A bank called «User / Temp» offers a selection of presets with a basic configuration (or template) to start programming a sound. (The sound «1_Osc», for example, co[...]

AR TURIA – minimoog V – USER’S MA NUAL 12 Setting the range of oscillator 1(«Range») By performing these first settings, you have already modified the «JMB_Classic1» preset. You can now save the sound th at you have just created.  To save a «user» preset, click on the save icon on the toolbar: The settings of the current sound will b[...]

AR TURIA – minimoog V – USER’S MA NUAL 13 2.2 T HE PLAYING MODES The minimoog V offers 2 playing modes: • T he «Close» mode is close to th e original configuration of the Minimoog. The closed mode (the original Minimoog) • The «Open» mode gives access to extensio ns offering a modulation matrix, an arpeggiator and effects. These dif f[...]

AR TURIA – minimoog V – USER’S MA NUAL 14 Opening the extension To use the minimoog V exactly like th e original Minimoog, you must also deactivate the chorus and delay effects on the toolbar and switch off the polyphony toggle in the output section. 2.3 O VERVIEW OF THE «C LOSE » MODE The «Close» mode h olds 50 synthesis settings, which [...]

AR TURIA – minimoog V – USER’S MA NUAL 15  Start by lowering th e cut-off frequ ency of the low- pass filter (LPF). This will make the sound more and more dampened.  To do this, set the «Cutoff frequency pote ntiometer». For fine-tuning, use the ri ght mouse button (t his is valid for all potentiometers). Notice that the filter cut-of[...]

AR TURIA – minimoog V – USER’S MA NUAL 16 2.4.1 The modulation matrix The modulation matrix mu ltiplies the possibilities for editin g sound when compared t o the original instrument. You can choose 6 sources (sub osc., envelopes, etc…) to modulate 6 destinations (freq. Osc., freq. VCF, etc…). The choice of source and destination is done [...]

AR TURIA – minimoog V – USER’S MA NUAL 17  Between the LCD displays can be found the «AMOUNT» knob. You can set the modulation level by applying po sitive (turn to the right) or negative (turn to the left) values. For this example, take a value of 0.0480. Turn the knob to the right to apply a positive value Let’s delay the action of th[...]

AR TURIA – minimoog V – USER’S MA NUAL 18 2.6 T HE EFFECTS SECTION The effects section lets you add ch orus or delay to your sound. 2.6.1 The chorus The Chorus eff ect enables to double and slight ly detune your sound in order to make it deeper and livelier. 3 types of stereo chorus are available.  Activate the «ON/OFF» button for Chorus[...]

AR TURIA – minimoog V – USER’S MA NUAL 19 2.7 T HE REAL TIME CONTROLLERS AND MIDI ASSIGN Like its excellent ancestor, the minimoog V is adapted in particular to real time play. One of the major points of evolution when compared to the original is the possibility to assign any minimoog V knob to an external MIDI controlle r. Let’s look at an[...]

AR TURIA – minimoog V – USER’S MA NUAL 20 3 THE INTERFACE 3.1 U SE OF PRESETS Presets let you memorize the sounds of the mi nimoog V. A preset contains all of the information pertaining to the reproduction of a sound. In the program, the presets are classed in «banks» and «sub-banks». Each ba nk contains a certain number of sub-banks, whi[...]

AR TURIA – minimoog V – USER’S MA NUAL 21 Choice of a preset in another sub-bank To choose a preset in anothe r main bank, click on the button. A dropdown menu appears with a list of the main banks availa ble with the sub-banks corresponding to the sub-banks defined in each main bank and to the presets contained in each sub-bank. You can thus[...]

AR TURIA – minimoog V – USER’S MA NUAL 22 Choice of preset regardless of bank When a preset has been modified an asterisk appears next to its name i n the tool bar. 3.1.2 Creation of a bank, sub-bank, preset To create a new bank, click on the button. The dropdown menu displays the names of all of the existing banks of sounds, an d a line call[...]

AR TURIA – minimoog V – USER’S MA NUAL 23 settings), or to save your setti ngs as a new preset (in this case, cl ick on «New preset...» in the sub-bank of your choice). «Save As» button and save menu in the tool bar When you are working from a factory preset, which cannot be deleted, clicking on the «Save» button will not replace the cu[...]

AR TURIA – minimoog V – USER’S MA NUAL 24 3.2 U SE OF CONTROLLERS 3.2.1 Knobs Generally the sequencers offer several knob control modes. The default mode of control for knobs with th e mouse is the circular mode: click on the k n o b a nd t ur n a ro un d it in or de r t o c ha ng e the value of the controlle r. The circular mode gives high p[...]

AR TURIA – minimoog V – USER’S MA NUAL 25 3.2.4 Virtual keyboard The keyboard lets you listen to the synthesi zer sounds without the need for an external master MIDI keyboard, and without programming a melody in the se quencer. Just click on a virtual key to hear the corresponding sound. 3.2.5 MIDI control Most of the knobs, sliders and switc[...]

AR TURIA – minimoog V – USER’S MA NUAL 26 4 THE SYNTHESIZER When it is set to «C lose» mode, the min imoog V remains very close to the original synthesizer. It is composed of two parts, one containing the synthesis parameters, the other being the keyboard and the modulation wheels. The synthesis panel is separated into several sub-groups, c[...]

AR TURIA – minimoog V – USER’S MA NUAL 27 View of the open minimoog V 4.1 T HE OSCILLATORS The minimoog V has three indepen dent oscillators which can be found in the «Oscillator Bank» section in the synthesis panel. Oscillators[...]

AR TURIA – minimoog V – USER’S MA NUAL 28 Each of t hese oscillators can produc e different waveforms wh ich are selected using the knob on the right. The first two generate, from left to right, a triangle , an asymmetric triangle, a descen ding sawtooth, a square, asymmetric square and impulse. The third oscillator replaces the asymmetric tr[...]

AR TURIA – minimoog V – USER’S MA NUAL 29 There are five sound sources av ailable, the three oscillators, a n oise generator and external audio in . The level of the t hree oscillators is set with each of the «Volume » knobs. The external signal level with the «Ext ernal Input Volume» k nob, the noise lev el with the «Noise Volu me» kno[...]

AR TURIA – minimoog V – USER’S MA NUAL 30 The «Cutoff frequency» knob sets the cut-o ff frequency. The «emphasis» knob sets the level of resonance and «Amount of Contour» the action of the envelope generator associated to the filter. It should be n oted that this filter au to-oscillates, which is t o say that when t he resonance is set [...]

AR TURIA – minimoog V – USER’S MA NUAL 31 This VCA is also controlled by an en velope generator which is set in the same manner as the envelope generator associated to the filter. Envelope generator associated to the VCA parameters This envelope generator is set with the «atta ck time» knobs for the attack time, and the «decay time» knob [...]

AR TURIA – minimoog V – USER’S MA NUAL 32 In «Low» mode, w e will hear the lowest n ote, in «High» mode th e highest note, and in «Last» mode the last note played on the keyboard. In the two first modes, when the not e is released, we will hear the lowest note (or respectively the highest) without triggeri ng the envelopes. In the last [...]

AR TURIA – minimoog V – USER’S MA NUAL 33 4.6 T HE PITCH BEND AND MODULATION WHEELS On the left of t he keyboard we find t wo wheels, one for modifyin g the oscillator frequency, the other for varying the amplitud e of the modulation brought by the third oscillator, either on th e oscillator frequency, or the filter cut-of f frequency. When t[...]

AR TURIA – minimoog V – USER’S MA NUAL 34 4.8 THE MODULATION MATRIX The minimoog V increases the original possibilities of modulation thanks t o the presence of the modulation matrix in the extension. This extension appears when the minimoog V is in open position. Modulation matrix This matrix can be activated or deactivated with the selector[...]

AR TURIA – minimoog V – USER’S MA NUAL 35 • CutOff: Filter cut-off frequency • E mphasis: Level of filt er resonance • EG VCF Att.: Attack time of fi lter envelope • EG VCF Dec.: Decay time of filter envelope • EG VCF Sus.: Sustain level of VCA envelope • EG VCF Lev: Output level of VCA envelope • EG VCA Att.: Attack time of VCA[...]

AR TURIA – minimoog V – USER’S MA NUAL 36 4.10 T HE ARPEGGIATOR Situated in the minimoog V extensi on which appears when in open mode, the arpeggiator allows for each note the activation of an arpeggio. Arpeggiator The «Speed» knob sets the speed of the arpeggio. The «Midi sync» switch lets you sy nchronize delay ret urn time with the h o[...]

AR TURIA – minimoog V – USER’S MA NUAL 37 5 THE BASICS OF SUBTRACTIVE SYNTHESIS Of all forms of sound synt hesis, subtractive synt hesis is one of the oldest and still certainly one of the most employed today. It is this method that was developed toward the end of the 60’s on analog synthesize rs li ke the Moog, ARP, Yamaha, Buchla, Oberhei[...]

AR TURIA – minimoog V – USER’S MA NUAL 38  The waveform which determin es the harmonic ric hness of the audio signal. On the minimoog V, 6 waveforms are available: • The saw tooth presents the richest audi o signal of the 4 wavefo rms (it contains all of the harmonics at decreasing volu me levels in high frequencies) . Its sound is ideal[...]

AR TURIA – minimoog V – USER’S MA NUAL 39 The original Minim oog proposed 3 types of square waveforms (square – 50%, wide rectangl e – 25% and narrow rectangle – 10%). This choice allowed compen sation for the missing PWM setting. The minimoog V offers these 3 waveforms but includes also the pulse width modulation. • The triangle can [...]

AR TURIA – minimoog V – USER’S MA NUAL 40 In the above image, oscillator2 is synchronized with the first and tuned to with double the tonality. The resulting waveform is unique in that it cannot be created by standard synthesis techniques such as layering or filtering. A frequency modulation ( FM ) can be created between 2 oscillators by conn[...]

AR TURIA – minimoog V – USER’S MA NUAL 41 On the minimoog V, you will find the noise generato r am ongst the settings in the mixer panel. A switch allows you to choose between the white and the pink noise. The noise generator set on the mixer 5.1.2 The filter or VCF The audio signal generated by an oscillator (the waveform) is n ext generally[...]

AR TURIA – minimoog V – USER’S MA NUAL 42 Spectrum of a noise signal proceed with a low-pass filter A second setting to compliment th e cut-off frequency: the resonance . (you will also find it called «emphasis» or «Q» – for Quality of filt ering) The resonance amplifies frequencies close to the cut-off frequency. The other frequencies [...]

AR TURIA – minimoog V – USER’S MA NUAL 43 5.1.3 The amplifier or VCA The amplifier ( Voltage Controlled Amplifier ) receives the audio si gnal coming from the filter (or directly from t he oscillator if it is not bein g filtered) to be adjusted before the volume is sent to the speakers. The minimoog V VCA In conclusion, here is a diag ram tha[...]

AR TURIA – minimoog V – USER’S MA NUAL 44 5.2.2 The envelope generator The envelope generator, connected to the amplif ier, is used to «sculpt» t he volume of th e sound when we press a key on the keyboard and ends after the note is released. The most common modules developed us e 4 settings that we can vary:  The A ttack is th e sound t[...]

AR TURIA – minimoog V – USER’S MA NUAL 45 The LFO module of the minimoog V Now to finish, here is the diagram of a co mplete synthesis voice on the minimoog V containing:  3 oscillators (VCO)  1 noise module  1 mixer (mixing of the 2 VC O and the noise module towa rds the low-pass and high- pass filters)  1 low-pass filter (VCF) ?[...]

AR TURIA – minimoog V – USER’S MA NUAL 46 6 A FEW ELEMENTS OF SOUND DESIGN Here is a series of examples designed to gu ide you through the creation of a sound and a sequence. They are classed in order of diffi culty going from the easi est to the most difficult and are organized into 3 parts:  The first part will help you t o grasp subtrac[...]

AR TURIA – minimoog V – USER’S MA NUAL 47 You will notice th at the sound is part icularly linear and withou t life. The sawtooth signal f rom the first oscillator goes throu gh a filter where the cut-off frequency is set to the maximum. This minimalist configu ration will let you easily perform some simple experiments with this basic sound. [...]

AR TURIA – minimoog V – USER’S MA NUAL 48  Increase the decay time for the filter envelope («Decay») to a value somewhere around 400 ms so that the cut-off frequenc y progressively decays when you press a key. You will thus obtain a simple yet efficient bass sound. Increase the decay time for the filter envelope  You can now save your[...]

AR TURIA – minimoog V – USER’S MA NUAL 49 Lightly detune oscillator 2 from t he two others by t urning this same knob w ith the left mouse button. The sound will begin t o “move” slightly an d sound “warmer”. If you want a sou nd that is «fat ter», click on the «Un ison» switch which brings all of the polyphonic voices to the same[...]

AR TURIA – minimoog V – USER’S MA NUAL 50 Increase the amplitude envelope attack time  Do the same with the filter envelope.  Place the «Range» kn ob of oscillator3 to Low mono (t he last position on the left). It will oscillate in low fr equencies (like a LF O)  Lower the tuning to – 48 ( - 4 octaves) by turning the central knob[...]

AR TURIA – minimoog V – USER’S MA NUAL 51 • 2 oscillat ors • 1 ligh tly resonant low- pass filter • 1 output VCA • The filter and VC A envelopes are active • Oscillat or 3 modulates the 2 other oscillators f or a vibrato effect brought by t he action of the modulation wheel. The modulation matrix will be active for: • A modulation[...]

AR TURIA – minimoog V – USER’S MA NUAL 52 Turn the «Amount» knob  For the 2 nd source of modulation, choose the «v elocity» to modulate the filt er «Cutoff».  Turn the «Amount» knob to a value of 0.31% . The velocity to modulate the «Cutoff»  Place the «Range» kn ob of oscillator3 to Low mono (t he last position on the le[...]

AR TURIA – minimoog V – USER’S MA NUAL 53  Play a chord bet ween C4 and C6, the notes will be played one af ter the other in th e order in which you have placed them. (it is possible to changing the playing order by clicking on the linear « mode» knob)  If you want, it is possible to keep the chord continuous by cl icking on the «Hol[...]

AR TURIA – minimoog V – USER’S MA NUAL 54 ► To clearly hear the different depths of modulation, simply in crease the value of the «Depth» knob. The higher the value, the more detuned the sound becomes! For a classic chorus, use minimal values (around 0.16) The «Depth» parameter ► Set the modulation speed by turning the «rat e» knob.[...]

AR TURIA – minimoog V – USER’S MA NUAL 55  A 2 position «MIDI Sync» swit ch synchronizes the repetition time with the tempo of the host application. T his will help to quickly f ind the appropriate timing for each side. Try for example the values «Tempo» (synch ronized to a crotchet) for the left and «Tempo 1.5» (synchronized to a do[...]

ART U R I A – minimoog V – USER’S MANUA L 56 7 MODES OF USE OF THE MINIMOOG V 7.1 S TAND - ALONE The minimoog V application can be used as an instrument indepen d ently of a sequencer ( stand alone mode). This lets you open on e or several instruments, and to play with a master MIDI keyboard. Attention ! The standalone is only available on PC[...]

ART U R I A – minimoog V – USER’S MANUA L 57 Mac preferences window • Protocol (PC only) : Select the audio protocol that yo u wi sh to use. If you have Asio drivers for your sound card, we recommend that you use this protocol instead of DirectX. The Asio drivers offer increase d performances compared to the DirectX drivers. • Driver : Se[...]

ART U R I A – minimoog V – USER’S MANUA L 58 7.1.3.2 Configuration of the keyboard zone The keyboard zone lets you use just one section of your keyboard to command the instrument. In this manner, you can play several instruments on the same keyboard, each one on a different zone. To activate this function, check the ‘zone’ option in the t[...]

ART U R I A – minimoog V – USER’S MANUA L 59 7.2 VST™ 7.2.1 Installation 7.2.1.1 For Windows During the installation, check the «VST» opti on among the plug-in formats proposed. The installer will au tomatically detect the VST instru ment folder used by you r version of Cubase. In the case of another VST compatib le sequencer, like Logi c[...]

ART U R I A – minimoog V – USER’S MANUA L 60 Connection of a MIDI track to the minimoog V The MIDI events played on a MIDI keyboard are then transmitted by your sequencer to the minimoog V. It is of course possible to record these MIDI events, and use all of the MIDI editing options of the sequencer. 7.2.4 Saving presets When the session is s[...]

ART U R I A – minimoog V – USER’S MANUA L 61 7.3 P RO T OOLS ™ 7.3.1 Installation During the inst allation, select the RTAS/HT DM plug-in (RTAS on ly for PC) among the choice of plug-ins offered. Then, when you ar e asked, indicate the folder where the other RTAS and HTDM plug-in s are installed. Generally the access is: • for Mac OS 9: S[...]

ART U R I A – minimoog V – USER’S MANUA L 62 Opening the minimoog V in Pro Tools for Mac OS X • TDM systems: the minimoog V should be loaded to a stereo audio track. Opening as HTDM is done through the TDM menu, as a HTDM plug-in is used exactly li ke a TDM plug-in. • Other systems: the minimoog V can be loaded on a mono audio track (whic[...]

ART U R I A – minimoog V – USER’S MANUA L 63 7.4 DX I ™ The minimoog V is compatible with the Dxi protocol, and so can se used notably with Sonar, but also with all other sequen cers that accept Dxi instruments. 7.4.1 Installation During the installation, check the «DXi » option among the list of protocols that you want to activate for th[...]

ART U R I A – minimoog V – USER’S MANUA L 64 7.4.4 Saving presets When the session is saved, th e state of the minimoog V is saved as is, even if the programming corresponds to no preset. For ex ample, if you were working on a preset «BassOne» on which you had changed settings (without sa vi ng them as «BassTwo»), the next time you open t[...]

ART U R I A – minimoog V – USER’S MANUA L 65 7.5 D IGITAL P ERFORMER ™ 7.5.1 Installation During the installation procedure, check the MAS choice among the plug-in formats offered. The minimoog V w ill be automatically installed in t he MAS plug-in folder: System Folder/Extensions/MOTU/Plug-ins To use the minimoog V, y ou will need to incre[...]

ART U R I A – minimoog V – USER’S MANUA L 66 7.5.4 Saving presets When the session is saved, th e state of the minimoog V is saved as is, even if the programming corresponds to no preset. For ex ample, if you were working on a preset «BassOne» on which you had changed settings (without sa vi ng them as «BassTwo»), the next time you open t[...]

AR TURIA – minimoog V – USER’S MA NUAL 67 8 FROM THE FIRST MOOG SYNTHESIZERS UP TO TAE «Mind you, neither of us had an y idea where this was leading»* 8.1 THE GENESIS OF THE MINIMOOG SYNTHESIZER Robert A. Moog was born in May 1934 in Ne w York. With a passion for music (he took piano lessons for 12 years), he was introduced to electronics b[...]

AR TURIA – minimoog V – USER’S MA NUAL 68 The modular system III (1967) Courtesy of Roger Luther, MoogArchives.com Success grew, and big groups like Tan gerine Dream, the Beatles and the Rolling Stones would also become modular Moog owners. In 1969, the company which at that time ha d around 40 employees was building up to 3 modulars per week[...]

AR TURIA – minimoog V – USER’S MA NUAL 69 Moog synthesizers sales figures - 1967-1971 Courtesy of Roger Luther, MoogArchives.com The very first Minimoog prototype was called Model A. Three other versions, B, C and D, followed. This last model is th e final and most common incarn ation of the Minimoog synthesizer and the only one th at was put[...]

AR TURIA – minimoog V – USER’S MA NUAL 70 Minimoog Model D Courtesy of Roger Luther, MoogArchives.com The Minimoog knew an unparalleled success during the 1970’s. Artists and bands like Tangerine Dream, Kraftwerk, Depeche Mode , Keith Emerson, Jean-Michel Jarre, Klaus Schulze, and Rick Wakeman used the synthesi zer, notably for the typical [...]

AR TURIA – minimoog V – USER’S MA NUAL 71 8.2 A BETTER EMULATION THANKS TO TAE ® TAE ® - standing for True Analog Emulation - is a new technology dedicated to the digital reproduction of analog circuits. When implemented in software code, TAE’s al gorithms guaranty the respect of hardware specifications. This is w hy the minimoog V offers[...]

AR TURIA – minimoog V – USER’S MA NUAL 72 8.2.2 Better reproduction of analog waveforms: Original analog oscillators used condensers’ unloading to produce common w ave shapes (saw tooth, triangle, squ are). This means that waveforms were slightly curv ed. TAE ® allows the reproduction of Condenser’s Unload. Temporal representation of a w[...]

AR TURIA – minimoog V – USER’S MA NUAL 73 8.2.3 Better reproduction of analog filters TAE allows the emu lation of analog-designed filt ers in a much more precise way than any existing digital filter. In particular, TAE has managed to reproduce the legendary Moog 24dB low-pass resonant filter with great respect towards the origi nal. Comparat[...]

AR TURIA – minimoog V – USER’S MA NUAL 74 8.2.4 Implementation of the soft clipping In analog synthesizers the resonant filter us es a current limiting f unction, preventing the signal from being too loud (soft clipping). TAE reproduces this current limiting f unction , making the sound more natural. It also allows filters to ent er self-osci[...]