diff --git a/Tone/event/ToneEvent.test.ts b/Tone/event/ToneEvent.test.ts
new file mode 100644
index 00000000..adf40318
--- /dev/null
+++ b/Tone/event/ToneEvent.test.ts
@@ -0,0 +1,485 @@
+import { expect } from "chai";
+import { BasicTests } from "test/helper/Basic";
+import { Offline, whenBetween } from "test/helper/Offline";
+import { Time } from "Tone/core/type/Time";
+import { noOp } from "Tone/core/util/Interface";
+import { ToneEvent } from "./ToneEvent";
+
+describe("ToneEvent", () => {
+
+	BasicTests(ToneEvent);
+
+	context("Constructor", () => {
+
+		it("takes a callback and a value", () => {
+			return Offline(() => {
+				const callback = noOp;
+				const note = new ToneEvent(callback, "C4");
+				expect(note.callback).to.equal(callback);
+				expect(note.value).to.equal("C4");
+				note.dispose();
+			});
+		});
+
+		it("can be constructed with no arguments", () => {
+			return Offline(() => {
+				const note = new ToneEvent();
+				expect(note.value).to.be.null;
+				note.dispose();
+			});
+		});
+
+		it("can pass in arguments in options object", () => {
+			return Offline(() => {
+				const callback = noOp;
+				const value = { a : 1 };
+				const note = new ToneEvent({
+					callback,
+					loop : true,
+					loopEnd : "4n",
+					probability : 0.3,
+					value,
+				});
+				expect(note.callback).to.equal(callback);
+				expect(note.value).to.deep.equal(value);
+				expect(note.loop).to.be.true;
+				expect(note.loopEnd).to.equal(Time("4n").valueOf());
+				expect(note.probability).to.equal(0.3);
+				note.dispose();
+			});
+		});
+	});
+
+	context("Get/Set", () => {
+
+		it("can set values with object", () => {
+			return Offline(() => {
+				const callback = noOp;
+				const note = new ToneEvent();
+				note.set({
+					callback,
+					loop : 8,
+					value : "D4",
+				});
+				expect(note.callback).to.equal(callback);
+				expect(note.value).to.equal("D4");
+				expect(note.loop).to.equal(8);
+				note.dispose();
+			});
+		});
+
+		it("can set get a the values as an object", () => {
+			return Offline(() => {
+				const callback = noOp;
+				const note = new ToneEvent({
+					callback,
+					loop : 4,
+					value : "D3",
+				});
+				const values = note.get();
+				expect(values.value).to.equal("D3");
+				expect(values.loop).to.equal(4);
+				note.dispose();
+			});
+		});
+	});
+
+	context("ToneEvent callback", () => {
+
+		it("does not invoke get invoked until started", () => {
+			return Offline(({transport}) => {
+				const event = new ToneEvent(() => {
+					throw new Error("shouldn't call this callback");
+				}, "C4");
+				transport.start();
+			}, 0.3);
+		});
+
+		it("is invoked after it's started", () => {
+			let invoked = false;
+			return Offline(({transport}) => {
+				const note = new ToneEvent(() => {
+					note.dispose();
+					invoked = true;
+				}, "C4").start(0);
+				transport.start();
+			}, 0.3).then(() => {
+				expect(invoked).to.be.true;
+			});
+		});
+
+		it("passes in the scheduled time to the callback", () => {
+			let invoked = false;
+			return Offline(({transport}) => {
+				const now = 0.1;
+				const note = new ToneEvent((time) => {
+					expect(time).to.be.a("number");
+					expect(time - now).to.be.closeTo(0.3, 0.01);
+					note.dispose();
+					invoked = true;
+				});
+				note.start(0.3);
+				transport.start(now);
+			}, 0.5).then(() => {
+				expect(invoked).to.be.true;
+			});
+		});
+
+		it("passes in the value to the callback", () => {
+			let invoked = false;
+			return Offline(({transport}) => {
+				const note = new ToneEvent((time, thing) => {
+					expect(time).to.be.a("number");
+					expect(thing).to.equal("thing");
+					note.dispose();
+					invoked = true;
+				}, "thing").start();
+				transport.start();
+			}, 0.3).then(() => {
+				expect(invoked).to.be.true;
+			});
+		});
+
+		it("can mute the callback", () => {
+			return Offline(({transport}) => {
+				const note = new ToneEvent(() => {
+					throw new Error("shouldn't call this callback");
+				}, "C4").start();
+				note.mute = true;
+				expect(note.mute).to.be.true;
+				transport.start();
+			}, 0.3);
+		});
+
+		it("can trigger with some probability", () => {
+
+			return Offline(({transport}) => {
+				const note = new ToneEvent(() => {
+					throw new Error("shouldn't call this callback");
+				}, "C4").start();
+				note.probability = 0;
+				expect(note.probability).to.equal(0);
+				transport.start();
+			}, 0.3);
+		});
+	});
+
+	context("Scheduling", () => {
+
+		it("can be started and stopped multiple times", () => {
+			return Offline(({transport}) => {
+				const note = new ToneEvent().start(0).stop(0.2).start(0.4);
+				transport.start(0);
+				return (time) => {
+					whenBetween(time, 0, 0.19, () => {
+						expect(note.state).to.equal("started");
+					});
+					whenBetween(time, 0.2, 0.39, () => {
+						expect(note.state).to.equal("stopped");
+					});
+					whenBetween(time, 0.4, Infinity, () => {
+						expect(note.state).to.equal("started");
+					});
+				};
+			}, 0.5);
+		});
+
+		it("restarts when transport is restarted", () => {
+
+			return Offline(({transport}) => {
+				const note = new ToneEvent().start(0).stop(0.4);
+				transport.start(0).stop(0.5).start(0.55);
+				return (time) => {
+					whenBetween(time, 0, 0.39, () => {
+						expect(note.state).to.equal("started");
+					});
+					whenBetween(time, 0.4, 0.5, () => {
+						expect(note.state).to.equal("stopped");
+					});
+					whenBetween(time, 0.55, 0.8, () => {
+						expect(note.state).to.equal("started");
+					});
+				};
+			}, 1);
+		});
+
+		it("can be cancelled", () => {
+			return Offline(({transport}) => {
+				const note = new ToneEvent().start(0);
+				expect(note.state).to.equal("started");
+				transport.start();
+
+				let firstStop = false;
+				let restarted = false;
+				const tested = false;
+				return (time) => {
+					// stop the transport
+					if (time > 0.2 && !firstStop) {
+						firstStop = true;
+						transport.stop();
+						note.cancel();
+					}
+					if (time > 0.3 && !restarted) {
+						restarted = true;
+						transport.start();
+					}
+					if (time > 0.4 && !tested) {
+						restarted = true;
+						transport.start();
+						expect(note.state).to.equal("stopped");
+					}
+				};
+			}, 0.5);
+		});
+
+	});
+
+	context("Looping", () => {
+
+		it("can be set to loop", () => {
+			let callCount = 0;
+			return Offline(({transport}) => {
+				new ToneEvent({
+					callback(): void {
+						callCount++;
+					},
+					loop : true,
+					loopEnd : 0.25,
+				}).start(0);
+				transport.start(0);
+			}, 0.8).then(() => {
+				expect(callCount).to.equal(4);
+			});
+
+		});
+
+		it("can be set to loop at a specific interval", () => {
+			return Offline(({transport}) => {
+				let lastCall;
+				new ToneEvent({
+					callback(time): void {
+						if (lastCall) {
+							expect(time - lastCall).to.be.closeTo(0.25, 0.01);
+						}
+						lastCall = time;
+					},
+					loop : true,
+					loopEnd : 0.25,
+				}).start(0);
+				transport.start();
+			}, 1);
+		});
+
+		it("can adjust the loop duration after starting", () => {
+			return Offline(({transport}) => {
+				let lastCall;
+				const note = new ToneEvent({
+					loop : true,
+					loopEnd : 0.5,
+					callback(time): void {
+						if (lastCall) {
+							expect(time - lastCall).to.be.closeTo(0.25, 0.01);
+						} else {
+							note.loopEnd = 0.25;
+						}
+						lastCall = time;
+					},
+				}).start(0);
+				transport.start();
+			}, 0.8);
+		});
+
+		it("can loop a specific number of times", () => {
+			let callCount = 0;
+			return Offline(({transport}) => {
+				new ToneEvent({
+					loop : 3,
+					loopEnd : 0.125,
+					callback(): void {
+						callCount++;
+					},
+				}).start(0);
+				transport.start();
+			}, 0.8).then(() => {
+				expect(callCount).to.equal(3);
+			});
+		});
+
+		it("plays once when loop is 1", () => {
+			let callCount = 0;
+			return Offline(({transport}) => {
+				new ToneEvent({
+					loop : 1,
+					loopEnd : 0.125,
+					callback(): void {
+						callCount++;
+					},
+				}).start(0);
+				transport.start();
+			}, 0.8).then(() => {
+				expect(callCount).to.equal(1);
+			});
+		});
+
+		it("plays once when loop is 0", () => {
+			let callCount = 0;
+			return Offline(({transport}) => {
+				new ToneEvent({
+					loop : 0,
+					loopEnd : 0.125,
+					callback(): void {
+						callCount++;
+					},
+				}).start(0);
+				transport.start();
+			}, 0.8).then(() => {
+				expect(callCount).to.equal(1);
+			});
+		});
+
+		it("plays once when loop is false", () => {
+			let callCount = 0;
+			return Offline(({transport}) => {
+				new ToneEvent({
+					loop : false,
+					loopEnd : 0.125,
+					callback(): void {
+						callCount++;
+					},
+				}).start(0);
+				transport.start();
+			}, 0.8).then(() => {
+				expect(callCount).to.equal(1);
+			});
+		});
+
+		it("can be started and stopped multiple times", () => {
+			return Offline(({transport}) => {
+				const eventTimes = [0.3, 0.4, 0.9, 1.0, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9];
+				let eventTimeIndex = 0;
+				new ToneEvent({
+					loop : true,
+					loopEnd : 0.1,
+					callback(time): void {
+						expect(eventTimes.length).to.be.gt(eventTimeIndex);
+						expect(eventTimes[eventTimeIndex]).to.be.closeTo(time, 0.05);
+						eventTimeIndex++;
+					},
+				}).start(0.1).stop(0.2).start(0.5).stop(1.1);
+				transport.start(0.2).stop(0.5).start(0.8);
+			}, 2);
+		});
+
+		it("loops the correct amount of times when the event is started in the transport's past", () => {
+			let callCount = 0;
+			return Offline(({transport}) => {
+				const note = new ToneEvent({
+					loop : 3,
+					loopEnd : 0.2,
+					callback(): void {
+						callCount++;
+					},
+				});
+				transport.start();
+				let wasCalled = false;
+				return (time) => {
+					if (time > 0.1 && !wasCalled) {
+						wasCalled = true;
+						note.start(0);
+					}
+				};
+			}, 1).then(() => {
+				expect(callCount).to.equal(2);
+			});
+		});
+
+		it("reports the progress of the loop", () => {
+			return Offline(({transport}) => {
+				const note = new ToneEvent({
+					loop : true,
+					loopEnd : 1,
+				});
+				expect(note.progress).to.equal(0);
+				note.start(0);
+				transport.start();
+				return (time) => {
+					expect(note.progress).to.be.closeTo(time, 0.05);
+				};
+			}, 0.8);
+		});
+
+		it("progress is 0 when not looping", () => {
+			Offline(({transport}) => {
+				const note = new ToneEvent({
+					loop : false,
+					loopEnd : 0.25,
+				}).start(0);
+				transport.start();
+				return () => {
+					expect(note.progress).to.equal(0);
+				};
+			}, 0.2);
+		});
+	});
+
+	context("playbackRate and humanize", () => {
+
+		it("can adjust the playbackRate", () => {
+			return Offline(({transport}) => {
+				let lastCall;
+				new ToneEvent({
+					loop : true,
+					loopEnd : 0.5,
+					playbackRate : 2,
+					callback(time): void {
+						if (lastCall) {
+							expect(time - lastCall).to.be.closeTo(0.25, 0.01);
+						}
+						lastCall = time;
+					},
+				}).start(0);
+				transport.start();
+			}, 0.7);
+		});
+
+		it("can adjust the playbackRate after starting", () => {
+			return Offline(({transport}) => {
+				let lastCall;
+				const note = new ToneEvent({
+					loop : true,
+					loopEnd : 0.25,
+					playbackRate : 1,
+					callback(time): void {
+						if (lastCall) {
+							expect(time - lastCall).to.be.closeTo(0.5, 0.01);
+						} else {
+							note.playbackRate = 0.5;
+						}
+						lastCall = time;
+					},
+				}).start(0);
+				transport.start();
+			}, 1.2);
+
+		});
+
+		it("can humanize the callback by some amount", () => {
+			return Offline(({transport}) => {
+				let lastCall;
+				const note = new ToneEvent({
+					humanize : 0.05,
+					loop : true,
+					loopEnd : 0.25,
+					callback(time): void {
+						if (lastCall) {
+							expect(time - lastCall).to.be.within(0.2, 0.3);
+						}
+						lastCall += 0.25;
+					},
+				}).start(0);
+				transport.start();
+			}, 0.6);
+		});
+
+	});
+});
diff --git a/Tone/event/ToneEvent.ts b/Tone/event/ToneEvent.ts
new file mode 100644
index 00000000..71de0eb9
--- /dev/null
+++ b/Tone/event/ToneEvent.ts
@@ -0,0 +1,384 @@
+import "../core/clock/Transport";
+import { ToneWithContext, ToneWithContextOptions } from "../core/context/ToneWithContext";
+import { TicksClass } from "../core/type/Ticks";
+import { defaultArg, optionsFromArguments } from "../core/util/Defaults";
+import { noOp } from "../core/util/Interface";
+import { PlaybackState, StateTimeline } from "../core/util/StateTimeline";
+import { isBoolean, isDefined, isNumber } from "../core/util/TypeCheck";
+
+type ToneEventCallback = (time: Seconds, value: any) => void;
+
+interface ToneEventOptions extends ToneWithContextOptions {
+	callback: ToneEventCallback;
+	loop: boolean | number;
+	loopEnd: Time;
+	loopStart: Time;
+	playbackRate: Positive;
+	value: any;
+	probability: NormalRange;
+	mute: boolean;
+	humanize: boolean | Time;
+}
+
+/**
+ * ToneEvent abstracts away this.context.transport.schedule and provides a schedulable
+ * callback for a single or repeatable events along the timeline.
+ *
+ * @extends {Tone}
+ * @param callback The callback to invoke at the time.
+ * @param value The value or values which should be passed to the callback function on invocation.
+ * @example
+ * var chord = new ToneEvent(function(time, chord){
+ * 	//the chord as well as the exact time of the event
+ * 	//are passed in as arguments to the callback function
+ * }, ["D4", "E4", "F4"]);
+ * //start the chord at the beginning of the transport timeline
+ * chord.start();
+ * //loop it every measure for 8 measures
+ * chord.loop = 8;
+ * chord.loopEnd = "1m";
+ */
+export class ToneEvent extends ToneWithContext<ToneEventOptions> {
+
+	name = "ToneEvent";
+
+	/**
+	 *  Loop value
+	 */
+	private _loop: boolean | number;
+
+	/**
+	 *  The callback to invoke.
+	 */
+	callback: ToneEventCallback;
+
+	/**
+	 *  The value which is passed to the
+	 *  callback function.
+	 */
+	value: any;
+
+	/**
+	 *  When the note is scheduled to start.
+	 */
+	private _loopStart: Ticks;
+
+	/**
+	 *  When the note is scheduled to start.
+	 */
+	private _loopEnd: Ticks;
+
+	/**
+	 *  Tracks the scheduled events
+	 */
+	private _state: StateTimeline = new StateTimeline("stopped");
+
+	/**
+	 *  The playback speed of the note. A speed of 1
+	 *  is no change.
+	 */
+	private _playbackRate: Positive;
+
+	/**
+	 *  A delay time from when the event is scheduled to start
+	 */
+	private _startOffset: Ticks = 0;
+
+	/**
+	 *  private holder of probability value
+	 */
+	private _probability: NormalRange;
+
+	/**
+	 *  the amount of variation from the given time.
+	 */
+	private _humanize: boolean | Time;
+
+	/**
+	 *  If mute is true, the callback won't be invoked.
+	 */
+	mute: boolean;
+
+	constructor(options?: Partial<ToneEventOptions>);
+	constructor(callback?: ToneEventCallback, value?: any);
+	constructor() {
+
+		super(optionsFromArguments(ToneEvent.getDefaults(), arguments, ["callback", "value"]));
+		const options = optionsFromArguments(ToneEvent.getDefaults(), arguments, ["callback", "value"]);
+
+		this._loop = options.loop;
+		this.callback = options.callback;
+		this.value = options.value;
+		this._loopStart = this.toTicks(options.loopStart);
+		this._loopEnd = this.toTicks(options.loopEnd);
+		this._playbackRate = options.playbackRate;
+		this._probability = options.probability;
+		this._humanize = options.humanize;
+		this.mute = options.mute;
+		this.playbackRate = options.playbackRate;
+	}
+
+	static getDefaults(): ToneEventOptions {
+		return Object.assign(ToneWithContext.getDefaults(), {
+			callback : noOp,
+			humanize : false,
+			loop : false,
+			loopEnd : "1m",
+			loopStart : 0,
+			mute : false,
+			playbackRate : 1,
+			probability : 1,
+			value : null,
+		});
+	}
+
+	/**
+	 *  Reschedule all of the events along the timeline
+	 *  with the updated values.
+	 *  @param after Only reschedules events after the given time.
+	 *  @private
+	 */
+	private _rescheduleEvents(after: Ticks = -1): void {
+		// if no argument is given, schedules all of the events
+		this._state.forEachFrom(after, event => {
+			let duration;
+			if (event.state === "started") {
+				if (isDefined(event.id)) {
+					this.context.transport.clear(event.id);
+				}
+				const startTick = event.time + Math.round(this.startOffset / this._playbackRate);
+				if (this._loop === true || isNumber(this._loop) && this._loop > 1) {
+					duration = Infinity;
+					if (isNumber(this._loop)) {
+						duration = (this._loop) * this._getLoopDuration();
+					}
+					const nextEvent = this._state.getAfter(startTick);
+					if (nextEvent !== null) {
+						duration = Math.min(duration, nextEvent.time - startTick);
+					}
+					if (duration !== Infinity) {
+						// schedule a stop since it's finite duration
+						this._state.setStateAtTime("stopped", startTick + duration + 1);
+						duration = new TicksClass(this.context, duration);
+					}
+					const interval = new TicksClass(this.context, this._getLoopDuration());
+					event.id = this.context.transport.scheduleRepeat(
+						this._tick.bind(this), interval, new TicksClass(this.context, startTick), duration);
+				} else {
+					event.id = this.context.transport.schedule(this._tick.bind(this), new TicksClass(this.context, startTick));
+				}
+			}
+		});
+	}
+
+	/**
+	 *  Returns the playback state of the note, either "started" or "stopped".
+	 */
+	get state(): PlaybackState {
+		return this._state.getValueAtTime(this.context.transport.ticks);
+	}
+
+	/**
+	 *  The start from the scheduled start time
+	 */
+	protected get startOffset(): Ticks {
+		return this._startOffset;
+	}
+	protected set startOffset(offset) {
+		this._startOffset = offset;
+	}
+
+	/**
+	 *  The probability of the notes being triggered.
+	 */
+	get probability(): NormalRange {
+		return this._probability;
+	}
+	set probability(prob) {
+		this._probability = prob;
+	}
+
+	/**
+	 *  If set to true, will apply small random variation
+	 *  to the callback time. If the value is given as a time, it will randomize
+	 *  by that amount.
+	 * @example
+	 * event.humanize = true;
+	 */
+	get humanize(): Time | boolean {
+		return this._humanize;
+	}
+
+	set humanize(variation) {
+		this._humanize = variation;
+	}
+
+	/**
+	 *  Start the note at the given time.
+	 *  @param  time  When the event should start.
+	 */
+	start(time?: TransportTime): this {
+		time = this.toTicks(time);
+		if (this._state.getValueAtTime(time) === "stopped") {
+			this._state.add({
+				id : undefined,
+				state : "started",
+				time,
+			});
+			this._rescheduleEvents(time);
+		}
+		return this;
+	}
+
+	/**
+	 *  Stop the Event at the given time.
+	 *  @param  time  When the event should stop.
+	 */
+	stop(time?: TransportTime): this {
+		this.cancel(time);
+		time = this.toTicks(time);
+		if (this._state.getValueAtTime(time) === "started") {
+			this._state.setStateAtTime("stopped", time);
+			const previousEvent = this._state.getBefore(time);
+			let reschedulTime = time;
+			if (previousEvent !== null) {
+				reschedulTime = previousEvent.time;
+			}
+			this._rescheduleEvents(reschedulTime);
+		}
+		return this;
+	}
+
+	/**
+	 *  Cancel all scheduled events greater than or equal to the given time
+	 *  @param  time  The time after which events will be cancel.
+	 */
+	cancel(time?: TransportTime): this {
+		time = defaultArg(time, -Infinity);
+		time = this.toTicks(time);
+		this._state.forEachFrom(time, event => {
+			this.context.transport.clear(event.id as number);
+		});
+		this._state.cancel(time);
+		return this;
+	}
+
+	/**
+	 *  The callback function invoker. Also
+	 *  checks if the Event is done playing
+	 *  @param  time  The time of the event in seconds
+	 *  @private
+	 */
+	private _tick(time: Seconds): void {
+		const ticks = this.context.transport.getTicksAtTime(time);
+		if (!this.mute && this._state.getValueAtTime(ticks) === "started") {
+			if (this.probability < 1 && Math.random() > this.probability) {
+				return;
+			}
+			if (this.humanize) {
+				let variation = 0.02;
+				if (!isBoolean(this.humanize)) {
+					variation = this.toSeconds(this.humanize);
+				}
+				time += (Math.random() * 2 - 1) * variation;
+			}
+			this.callback(time, this.value);
+		}
+	}
+
+	/**
+	 *  Get the duration of the loop.
+	 */
+	private _getLoopDuration(): Ticks {
+		return Math.round((this._loopEnd - this._loopStart) / this._playbackRate);
+	}
+
+	/**
+	 *  If the note should loop or not
+	 *  between ToneEvent.loopStart and
+	 *  ToneEvent.loopEnd. If set to true,
+	 *  the event will loop indefinitely,
+	 *  if set to a number greater than 1
+	 *  it will play a specific number of
+	 *  times, if set to false, 0 or 1, the
+	 *  part will only play once.
+	 */
+	get loop(): boolean | number {
+		return this._loop;
+	}
+	set loop(loop) {
+		this._loop = loop;
+		this._rescheduleEvents();
+	}
+
+	/**
+	 * 	The playback rate of the note. Defaults to 1.
+	 *  @example
+	 * note.loop = true;
+	 * //repeat the note twice as fast
+	 * note.playbackRate = 2;
+	 */
+	get playbackRate(): Positive {
+		return this._playbackRate;
+	}
+	set playbackRate(rate) {
+		this._playbackRate = rate;
+		this._rescheduleEvents();
+	}
+
+	/**
+	 *  The loopEnd point is the time the event will loop
+	 *  if ToneEvent.loop is true.
+	 */
+	get loopEnd(): Time {
+		return new TicksClass(this.context, this._loopEnd).toSeconds();
+	}
+	set loopEnd(loopEnd) {
+		this._loopEnd = this.toTicks(loopEnd);
+		if (this._loop) {
+			this._rescheduleEvents();
+		}
+	}
+
+	/**
+	 *  The time when the loop should start.
+	 */
+	get loopStart(): Time {
+		return new TicksClass(this.context, this._loopStart).toSeconds();
+	}
+	set loopStart(loopStart) {
+		this._loopStart = this.toTicks(loopStart);
+		if (this._loop) {
+			this._rescheduleEvents();
+		}
+	}
+
+	/**
+	 *  The current progress of the loop interval.
+	 *  Returns 0 if the event is not started yet or
+	 *  it is not set to loop.
+	 */
+	get progress(): NormalRange {
+		if (this._loop) {
+			const ticks = this.context.transport.ticks;
+			const lastEvent = this._state.get(ticks);
+			if (lastEvent !== null && lastEvent.state === "started") {
+				const loopDuration = this._getLoopDuration();
+				const progress = (ticks - lastEvent.time) % loopDuration;
+				return progress / loopDuration;
+			} else {
+				return 0;
+			}
+		} else {
+			return 0;
+		}
+	}
+
+	dispose(): this {
+		super.dispose();
+		this.cancel();
+		this._state.dispose();
+		this.value = null;
+		return this;
+	}
+}