diff --git a/repl/src/xen.mjs b/repl/src/xen.mjs
index 14b08004..fc89bd60 100644
--- a/repl/src/xen.mjs
+++ b/repl/src/xen.mjs
@@ -2,10 +2,10 @@ import { Pattern } from '../../strudel.mjs';
 import { mod } from '../../util.mjs';
 
 function edo(name) {
-  if (!/^[1-9]+edo$/.test(name)) {
+  if (!/^[1-9]+[0-9]*edo$/.test(name)) {
     throw new Error('not an edo scale: "' + name + '"');
   }
-  const [_, divisions] = name.match(/^([1-9]+)edo$/);
+  const [_, divisions] = name.match(/^([1-9]+[0-9]*)edo$/);
   return Array.from({ length: divisions }, (_, i) => Math.pow(2, i / divisions));
 }
 
@@ -13,16 +13,23 @@ const presets = {
   '12ji': [1 / 1, 16 / 15, 9 / 8, 6 / 5, 5 / 4, 4 / 3, 45 / 32, 3 / 2, 8 / 5, 5 / 3, 16 / 9, 15 / 8],
 };
 
+function withBase(freq, scale) {
+  return scale.map((r) => r * freq);
+}
+
+const defaultBase = 220;
+
 function getXenScale(scale, indices) {
   if (typeof scale === 'string') {
-    if (/^[1-9]+edo$/.test(scale)) {
-      return edo(scale);
+    if (/^[1-9]+[0-9]*edo$/.test(scale)) {
+      scale = edo(scale);
+    } else if (presets[scale]) {
+      scale = presets[scale];
+    } else {
+      throw new Error('unknown scale name: "' + scale + '"');
     }
-    if (presets[scale]) {
-      return presets[scale];
-    }
-    throw new Error('unknown scale name: "' + scale + '"');
   }
+  scale = withBase(defaultBase, scale);
   if (!indices) {
     return scale;
   }
@@ -32,15 +39,19 @@ function getXenScale(scale, indices) {
 function xenOffset(xenScale, offset, index = 0) {
   const i = mod(index + offset, xenScale.length);
   const oct = Math.floor(offset / xenScale.length);
-  return xenScale[i] * 440 * Math.pow(2, oct);
+  return xenScale[i] * Math.pow(2, oct);
 }
 
-Pattern.prototype._xen = function (scaleNameOrRatios) {
+// scaleNameOrRatios: string || number[], steps?: number
+Pattern.prototype._xen = function (scaleNameOrRatios, steps) {
   return this._asNumber()._withEvent((event) => {
-    const frequency = xenOffset(getXenScale(scaleNameOrRatios), event.value);
+    const scale = getXenScale(scaleNameOrRatios);
+    steps = steps || scale.length;
+    const frequency = xenOffset(scale, event.value);
     return event.withValue(() => frequency).setContext({ ...event.context, type: 'frequency' });
   });
 };
+
 Pattern.prototype.tuning = function (steps) {
   return this._asNumber()._withEvent((event) => {
     const frequency = xenOffset(steps, event.value);