Homegrown Phase Shifter VSTi

HGS PHASE SHIFTER - MANUAL
In the late 60's composer Steve Reich stumbled across a technique he called phasing, which was to have two identical tape loops that run at slightly different speeds, the result is that every possible combination of sound is cycled through until they arrive back in sync. The result with a melodic piece of music is that it moves through moments of chaos and moments of melody. Brian Eno also used this technique extensively on some of his Ambient albums. After becoming interested in this in 2008, I decided to build myself a simple plugin to emulate the process as it was surprisingly difficult to emulate with any software I had at that time. I have now expanded it to emulate four tape decks and many more features such as time stretching, filters & FX so that it has become a much more capable synthesizer.
Phase Shifter is designed more for playing live, though full VST automation is supported and having an external controller makes the process a much more rewarding experience. It also has a built in recorder so that the output can be recorded directly to disk. It works by loading up to 2 WAVs, and is triggered via a midi keyboard. Middle C will play the WAV at it's original speed. It has a lot of potential for producing interesting sounds, I would be pleased to hear of the different ways people use it.
Here are some basic possible uses, and a quick guide to how it is achieved:
PHASING
Load up the default patch, Reich Piano Phase, which uses the base riff of one of Steve Reich's more famous phasing pieces. Hold down the middle C key and keep it held. You will hear that the loops slowly go out of sync and eventually they come back together having shifted through all combinations of sound. This patch is only using the top 2 Phase Shifters, you can see that the pitch knob on number 2 is slightly speeded up, and so is the one shifting forwards. When I use it for basic phasing I find it easier to always leave PS1 set to normal speed. You will also notice that the P1 and P2 buttons are enabled on PS2, this means that the speeding up is timestretched instead of the pitch altering. If P1 is switched off, then the pitch will alter with the speed (like a true tape deck). Try loading one of your own loops in this patch and playing with the speed.
LOOP HARMONISING
Another great use of Phase Shifter is the ability to retune a loop using the P1 pitch shift, and having N (Note Based) pressed. This means that there is no speed change, and so the loops will play in sync. Load the next patch 'Reich Piano Phase 2' to hear/see this in action. Playing with the pitch knob on PS2 you will hear that it moves in semitones.
COUNTERPOINT/SYNCOPATION
Sticking with the Piano Phase 2 patch, now move the start slider a couple of notches along and retrigger the note (middle C). You will now hopefully hear that WAV in PS2 has begun playback 2 beats in and so there is a delay type effect. This slider will move between 16 equal positions in the WAV.
I hope that gives an idea of some of the basic possibilities, there are also all of these techniques working together, using 2 WAVs and all 4 Phase Shifters some wonderful collages can be created, especially making use of the filters and panning, I hope that the presets will give some ideas of the scope, although I don't think it is really a preset machine, it is more exploratory. My personal favourite is patch 16 'Reverse Guitars' if you play that lower than middle C and keep the key held down for a long time, it is reminiscent to me of some of the early ambient Eno tracks.
Of course it can also be used as a synth and at times has a mellotron type feel. The added SoundScaper also adds another depth to explore.
Anyone interested in Steve Reich & Phasing, there is agreat South Bank Show documentary which is currently on youtube, part 1 is here:
Steve Reich - South Bank Show
OK, on with the manual:
All four samplers (tape decks) work identically and so I will just describe one:

- ON/OFF - Tope left button will switch each tape deck on or off.
- DEFAULT/RANDOM - The two buttons at the top, the left will set the tape sliders to their default settings, the right one will randomize the sliders.
- VOLUME - The overall volume of the tape deck.
- PAN - Stereo position of the tape deck.
- FREQ - The cutoff frequency of the filter
- RESON - The Resonance of the filter
- START - Allows selecting between 16 equal points in the WAV for the sample to start when triggered. This allows creating some syncopated rhythms.
- F TYPE - What kind of filter it will use such as Low Pass, Hi Pass and Band.
- RETRIGGER - The top Button will reset the sample playback on clicking.
- REVERSE - This will play the sample backwards.

This part deals with the pitch controls:

- (N) NOTE MODE - The top left button when switched on will make the pitch quantize to semitones which is useful if using with pads etc...
- (P1) DELAY BASED PITCH - The middle button switches on delay based pitch shifting which means that the tempo of the WAV will stay constant.
- (P2) NORMAL PITCH SHIFT - When this is switched on normal pitch shifting will be enabled, which means that the tempo will also be adjusted as the pitch changes.
- PITCH KNOB - This is used to control the tape speed, centre is no effect, to the right increases speed, to the left decreases speed. Double clicking will reset to centre.

NOTES:
The two different pitch modes (Delay based and Normal based), can interact with each other, for example if both delay based pitch and normal pitch are enabled, this will then become a timestretch so that the tempo will change but the pitch will stay constant. If both are switched off there will be no pitch change at all.
The master setting for Pitch Sensitivity will decide how sensitive all of the tape pitches are, using that slider which moves in semitones, up to an octave either way can be achieved. If (N) NOTE MODE is uised however, this will override the PITCH SENS setting. For actual Steve Reich type emulation something like a single semitone is more useful.
This section affects the entire output of Phase Shifter. The sliders can be double clicked to reset to default, also small movements are possible by clicking and holding the mouse at either end of the slider.

- FX - This will switch the entire FX Section on or off.
- DRIVE - Switches the Drive/Distortion ON or OFF, the amount is set by the slider below.
- LOAD WAV 1 - Will bring up a browse box to locate a WAV file to load which is used by Phase Shifters 1 and 2.
- LOAD WAV 2 - As above, but this WAV will be used by Phase Shifters 3 & 4.
- VOLUME - The overall Volume of the plugin
- MASTER PITCH - The master Pitch of the plugin +1/-1 Octave
- PITCH SENSITIVITY - This sets the range of all the pitch knobs on the tape emulators which moves in semitone steps. Setting to the first postion will mean that the Pitch Knobs will be disabled. Also using Note on the phase shifter will override this setting.
- FX MIX - Moves between the dry signal and the FX output, full right is entirely the effects output.
- CUTOFF - This will affect the Filter Cutoff all working Phase shifters. It is 0 at the centre and so to the left will reduce, and to the right will add, the relationship between all the individual Filters remains the same, they all will increase or decrease together. This can also be controlled via CC21, or by VST automation as can everything else in the Synth.
- ATTACK - Sets the Attack time of the volume envelope, allowing a fade in.
- RELEASE - The Release time of the volume envelope, ie; how long the sound will take to fade out.
- DRIVE - Sets the drive amount, which must be switched on by the above switch.

These options along the top affect the entire synth.

- VELOCITY - Enables Velocity control so that how hard a key is pressed will affect the overall volume of the sound envelope.
- VCF - When switched on the velocity will affect the filter cutoff.
- MONO - Switches from Polyphonic to Monophonic, good for lead sounds.
- LOFI - This degrade the samples to 8 bit.
- BEND - Selects how many semitones the Pitch Bender will max out at.

This menu allows selecteing the various different panels available, Main displays the Front View, FX the Effects, Help 1 and 2 display some quick help which may be useful when learening to use Phase Shifter.
The Recorder will record the output directly to WAV when Record is pressed, and continue recording until it is pressed again. First choose a location/name for the WAV file, and set the Bit Deptch using the up/down arrows. Be careful to use a new name for each recording otherwise it will destroy the existing one. Alternatively you can grab the Homegrown WAV Recorder which can be used in your VST chain to auto name your recordings.
Finally, hovering over the Phase Shiter Logo will bring up a context help for quick reference.
FX
Phase Shifter has two inbuilt effects, SoundScaper and Flanger/Filter. These can be routed either way round in serial.
SoundScaper is a plugin which can do many different effects from tight combs to endless complex & undulating delays, which is great for organic church bell type collages.

- COMBS - There are 8 comb filters altogether and the number in use is selected by the No. Combs setting which will use x many starting at the top. Dragging the mouse across the sliders allows changing the times, small increments can be made using the end nodules which will move the slider in the appropriate direction. Double clicking a slider will reset it to the default setting.
- DEFAULT - This will set all sliders to their default values (including COMB SCALE & COMB MIN)
- RANDOM - This will randomize all the sliders (including COMB SCALE & COMB MIN)
- TIME MODE - There are 58 modes which slowly increase in time as they progress. The names are a rough guide the extent of the delay. The selected mode will then multiply the comb sliders, and the COMB SCALE will also effect the actual time (see below)
- NO. COMBS - How many comb filters are used, starting from the top.
- NO. ALLPASS - How many Allpass filters the plugin will use which can help to create a more Reverb type sound.
- SMALL SCALE - Switching this off will double the timings, allowing very long delay times.
- COMB SCALE/COMB MIN - The COMB MIN stes the smallest delay time allowable, useful if working with tight comb effects to keep them tuneful. COMB SCALE allows setting times anywhere between COMB MIN and the current TIME MODE. Basically a rough way to change the entire timings whilst keeping the time relationship between the comb filters.
- D R - This Default will reset the entire SoundScaper to a nice Reverb sound/starting point. The Randomise will generate a new patch instantly.
- LOAD / SAVE - This allows saving and re-loading an entire SoundScaper preset externally. These patches can be loaded into some other HGS products such as Black Magic.
- FEEDBACK - This determines how long the effect will take to fade out, on full it will take a very long time.
- WIDTH - Sets the Stereo Width of the Effect
- DAMP - Sets how the sound will dampen/dull over time. Full right will dampen quickly, full left will not dampen at all.
- LEVEL - Master Level of the SoundScaper.
- GATE MODE - When enabled, SoundScaper will only be heard when a key is pressed/envelope is active.

The Flanger/Filter is an LFO base effect and so the effect can either be a Flange of use the selected filter.

- TEMPO - Sets the synced time that the LFO will sync to.
- FILTER - Select which type of filter to use when in Filter mode.
- WAVE SHAPE - There are 33 shapes to choose from as well as Custom Mode which will be explained below.
- CUSTOM WAVE - This allows selecting 1 of 150 pre-determind Waveshapes which can be used when Custom is selected in the WAVE SHAPE popup menu.
- SMOOTH - This is only for the Custom Waveshapes, and will determine how smoothly the transition from one point to another is processed. When set to 31 it will be smooth between all points like a SAW wave, when set to 0 it will be treated like a Square Wave.
- DEFAULT / RANDOM - Used to either set to default or to randomise a patch for the Flanger.
- FILTER - When this is enabled the selected filter will be used instead of the Flanger.
- DEPTH - The depth of the LFO.
- PHASE - Allows offsetting the midpoint of the LFO frequency.
- FEEDBACK - Controls the strength of the Flange/ Resonance of the Filter
- MIX - Mixes between the incoming signal and the Flange/Filter.

The Routing selects whether the Flanger comes before or after SoundScaper.
CREDITS:
Homnegrown Sounds - www.hgsounds.com
Plugin Design - Andy Medforth
GUI Design - Andreas Nillson
Phase Shifter was built using Synthedit - http://www.synthedit.com and uses some modules by Chris Kerry - http://www.chriskerry.f9.co.uk/
SynthEdit is a trademark of Jeff McClintock. VST and ASIO are trademarks of Steinberg Soft- und Hardware GmbH. All other copyrights and trademarks are the property of their respective owners.