Propiedades de los hidruros de Mg

Synchronizing playback of looped audio with the host tempo is easy to achieve by modulating the Position parameter appropriately. This technique is possible with any

synthesis method in Alchemy that permits continuous modulation of Position. In the example below, we use the Granular engine, but the same technique can be applied to the Additive and Spectral engines.

1. Initialize Alchemy by choosing the ‘Clear’ command in the Title bar’s FILE menu.

2. Load (into Source A) a rhythmic or melodic sample that works well when looped. Try

‘Factory’ > ‘Loops’ > ‘DrumLoops’ > ‘Cyborg-4bts.wav’. (The Load command imports this audio file quickly into the Granular engine. You could also Import the file, using any import mode, and the technique presented here would work fine.)

3. Now if you play and hold C3, the ‘Cyborg-4bts’ sample will play in a looped fashion.

(Note that the Loop mode is already set to ‘Continuous’ by default.) If your host tempo happens to be 120 BPM, the loop will stay in tempo reasonably well — but suppose you want to sync the loop automatically to a different tempo set in your host.

4. Turn the Source A Stretch knob down to its minimum value of 0%. Now if you play notes you’ll find that playback is frozen at the very beginning of the sample. (All you’ll hear is a low rumble, because all of the individual grains are being drawn from the low bass sound that begins the sample.)

5. Next we’ll assign a modulator to the Position parameter in order to control a playback path through the audio data. First we want the Position to increase smoothly so that the entire sample plays back from beginning to end, then we want the Position to jump immediately back to the beginning, and finally we want to repeat this path so that the sound loops. The right modulator for this job is an LFO with a ramp up shape. Click the Position knob in order to access its mod rack in the Modulation section. In the first mod rack slot, choose LFO 1, which brings the LFO 1 controls into view on the right-hand side of the Modulation section. Finally, choose ‘RampUp’ in the LFO Shape selection field and turn off the BIPOLAR button.

6. If you play and hold a note now, you’ll find that the sample is looping as required, but the playback speed is much too fast. As its name suggests, the ‘Cyborg-4bts’ sample has a length of four beats. At its default rate, LFO 1 completes a cycle every beat. Adjust the LFO Rate to ‘4 beats’. Play and hold another note to confirm that the playback speed is now correct.

7. Finally, adjust your host tempo as you play additional notes to confirm that the loop is properly synchronized with the host tempo.

To summarize what’s happening in this result: a tempo-synced LFO with a ramp up shape is controlling the Position knob, which causes playback to scan through the audio data in a

forward direction every four beats. The result is a tempo-synced loop. The diagram below depicts these relationships.

Note that it’s not actually necessary to ‘freeze’ the playback by setting Stretch to 0%, as we’ve done in step 4, before modulating Position. The LFO shape we’ve chosen (ramp up) is constantly changing, without any static/flat portions; this means that it always controls play position, which makes the value of Stretch irrelevant. (Try double-clicking

Stretch to restore its default 100% value. Then play a note: the looping behavior remains the same.) However, if we were to use a different LFO shape with static/flat portions, then setting Stretch to a non-zero value would cause play position to be controlled by a combination of the LFO shape and the normal play behavior of the sample. (Try changing the LFO shape to ‘RandHold’ — the results may be more musically interesting if you also increase the LFO rate to ‘1/2 beats’. Then play notes and compare the results you get with Stretch set to 0% versus 100%.)

Morph

The Morph X and Y controls determine how Alchemy’s four Sources interact. There two basic types of interaction.

 XFade. In an xfade (or ‘crossfade’), sounds from all four Sources are played at once, and the X and Y knobs control the mix between them. This is equivalent to turning the Amp knobs in each Source up and down to get the desired mix.

If you xfade from a Source with a high Coarse Tune setting to a Source with a low Coarse Tune setting, then the high Source will fade out as the low one fades in, and in the middle of the xfade you’ll hear the high and low Sources simultaneously.

 Morph. In a morph, a single sound is generated, and the parameters of that sound are determined by interpolating between the settings of all four Sources.

If you morph from a Source with a high Coarse Tune setting to a

Source with a low Coarse Tune setting, then you’ll hear a single sound during the entire morph, and its tuning will fall smoothly from the high value to the low one.

The Morph pop-up menu offers a variety of xfade and morph modes.

 xfade linear — The X knob crossfades from Source A to B to C to D as you increase it from 0% to 100%. (The Y knob does nothing in this mode.) This mode is useful for setting up crossfades based on Velocity or KeyFollow.

 morph linear — This mode is like xfade linear, but all the parameters of the sound are morphed. Regions of each source sound bounded by corresponding Warp Markers are time-aligned in the morph — the Source Edit (Main) page provides a fuller explanation.

 xfade xy — This is the default morph/xfade mode, and it crossfades between all four sources depending on the values of the X and Y knobs. X controls the mix levels of Source A & C versus B & D. Y controls the mix levels of Source A & B versus C & D.

 morph xy — This mode is like xfade xy, but all the parameters of the sound are

morphed. Regions of each source sound bounded by corresponding Warp Markers are time-aligned in the morph — the Source Edit (Main) page provides a fuller explanation.

Note that all of the remaining modes work similarly to morph xy, except that they provide control over the morph position of particular aspects of the sound. The settings you make in each of these more particular modes coexist with one another — for instance, if you first use the X and Y knobs in add xy mode (described below) to set values for the MorAddX and MorAddY parameters, then you can afterwards use the X and Y knobs in spec xy mode (described below) to adjust the

MorSpecX and MorSpecY parameters without losing your MorAddX and MorAddY settings.

 time xy — The X and Y knobs control the MorTimeX and MorTimeY parameters, which morph the timing of the sound, so if Source A has a short attack and Source B has a long attack, the length of the attack will vary as you change the X knob. In this mode, all the main Source parameters such as Amp, Pan, Tune, FilterMix, Position, and Stretch are morphed as well. (The attack portion of each sound is determined by the positioning of Warp Markers in the Source Editor’s MAIN view.)

 add xy — The X and Y knobs control the MorAddX and MorAddY parameters, which morph the Additive element between the settings of Sources A, B, C, and D.

 spec xy — The X and Y knobs control the MorSpecX and MorSpecY parameters, which morph the Spectral element between the settings of Sources A, B, C, and D.

 gran xy — The X and Y knobs control the MorGranX and MorGranY parameters, which morph the Granular element between the settings of Sources A, B, C, and D.

 filt xy — The X and Y knobs control the MorFiltX and MorFiltY parameters, which morph the settings of the three Source Filter cutoff and resonance values between the settings of Sources A, B, C, and D. (The filter types and on/off status set in Source A remain in effect throughout the morph.)

See the example at the bottom of this page for discussion of an easy way to work with several of these more particular morph modes simultaneously.