diff --git a/public/default.css b/public/default.css
index 050f72b..debf6e0 100644
--- a/public/default.css
+++ b/public/default.css
@@ -340,12 +340,26 @@ summary {
 
 .delete {
     position: absolute;
+    display: inline-block;
     right: 0;
     padding: 0;
     cursor: pointer;
     padding: 2px;
+    vertical-align: top;
 }
 
+.preview {
+    position: absolute;
+    display: inline-block;
+    left: 0;
+    padding: 0;
+    cursor: pointer;
+    padding: 2px;
+    vertical-align: top;
+    margin-top: 15px;
+}
+
+
 .intro {
     top: 40%;
     transform: translate(-50%);
diff --git a/server.js b/server.js
index 60b285a..27bed1b 100644
--- a/server.js
+++ b/server.js
@@ -57,6 +57,13 @@ fastify.get("/", function (request, reply) {
   reply.view("/src/pages/parade.html", {});
 });
 
+//get '/preview/:foldername'
+fastify.get("/preview/:foldername", function (request, reply) {
+  //
+  //request.params.foldername
+  reply.view("/src/pages/preview.html", {});
+});
+
 //get '/entry', '/entry/', '/en/entry', '/en/entry/'
 ["/entry", "/entry/", "/en/entry", "/en/entry/"].forEach(function(item) {
   fastify.get(item, async function (request, reply) {
@@ -105,7 +112,30 @@ fastify.get("/entries", async function (request, reply) {
   //get list
   let list = await fs.readdir('/media/storage/public/sound-parade/');
 
-  reply.send({ list: list });
+  reply.send(list);
+});
+
+//get '/fields'
+fastify.get("/fields", async function (request, reply) {
+
+  //get list
+  let list = await fs.readdir('/media/storage/public/sound-parade/');
+  //list.reverse();
+
+  // console.log(list);
+
+  let folders = [];
+  for (const item of list) {
+    var fields = JSON.parse((await fs.readFile('/media/storage/public/sound-parade/' + item + '/fields.json')).toString('utf8'));
+    folders.push({
+      foldername: item,
+      group: fields.group,
+      title: fields.title,
+      comment: fields.comment,
+    });
+  }
+
+  reply.send(folders);
 });
 
 //get '/delete'
diff --git a/src/pages/entry.en.html b/src/pages/entry.en.html
index 4f7198d..7c9410f 100644
--- a/src/pages/entry.en.html
+++ b/src/pages/entry.en.html
@@ -19,7 +19,6 @@
        max-width: 500px;
      }
     </style>
-    <link rel="stylesheet" href="/entry.css" />
     <script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/0.10.2/p5.js"></script>
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
@@ -59,14 +58,15 @@
               Place<br/>
               <a href="https://walkingtowardstheflow.xyz">walkingtowardstheflow.xyz</a>, <a href="https://www.youtube.com/c/franceencoree">France en Corée - YouTube channel</a>
             </p>
+            <p>
+              artists<br/>
+              <a href="https://dianaband.info" target="_blank">diana band</a> X <a href="https://cgyoon.kr/" target="_blank">Choong-geun Yoon</a> (Inquiry: wonjung24@gmail.com)
+            </p>
             <p>
               Parade Composition<br/>
               Flock0  promises — Flock1 flags — Flock2 bodies — Flock3 objects — Flock4 someone
             </p>
-            <p>
-              Inquiry<br/>
-              wonjung24@gmail.com
-            </p>
+
           </div>
         </section>
         <section class="participation">
@@ -148,6 +148,7 @@
                 <li>Title | <div class="title">{{this.title}}</div></li><hr>
                 <li>Desc. | <div class="comment">{{this.comment}}</div></li><hr>
               </ul>
+              <button class="preview" type="button" onclick="javascript:window.open('/preview/{{this.foldername}}', '_blank');">Preview</button>
               <button class="delete" type="button" onclick="del(this)">Delete</button>
             </details>
           </div>
diff --git a/src/pages/entry.html b/src/pages/entry.html
index b8cc172..a9a2aa7 100644
--- a/src/pages/entry.html
+++ b/src/pages/entry.html
@@ -19,7 +19,6 @@
        max-width: 500px;
      }
     </style>
-    <link rel="stylesheet" href="/entry.css" />
     <script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/0.10.2/p5.js"></script>
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
@@ -61,12 +60,12 @@
               <a href="https://walkingtowardstheflow.xyz">walkingtowardstheflow.xyz</a><br><a href="https://www.youtube.com/c/franceencoree">주한프랑스대사관 문화과 유튜브 채널</a>
             </p>
             <p>
-              퍼레이드 구성<br/>
-              무리0 약속들 — 무리1 깃발들 — 무리2 신체들 — 무리3 사물들 — 무리4 누구들
+              작가<br/>
+              <a href="https://dianaband.info" target="_blank">다이애나밴드</a> X <a href="https://cgyoon.kr/" target="_blank">윤충근</a> (문의: wonjung24@gmail.com)
             </p>
             <p>
-              문의<br/>
-              wonjung24@gmail.com
+              퍼레이드 구성<br/>
+              무리0 약속들 — 무리1 깃발들 — 무리2 신체들 — 무리3 사물들 — 무리4 누구들
             </p>
           </div>
         </section>
@@ -150,6 +149,7 @@
                 <li>제목 | <div class="title">{{this.title}}</div></li><hr>
                 <li>묘사 | <div class="comment">{{this.comment}}</div></li><hr>
               </ul>
+              <button class="preview" type="button" onclick="javascript:window.open('/preview/{{this.foldername}}', '_blank');">미리보기</button>
               <button class="delete" type="button" onclick="del(this)">삭제</button>
             </details>
           </div>
diff --git a/src/pages/parade.html b/src/pages/parade.html
index e2517f7..4471c22 100644
--- a/src/pages/parade.html
+++ b/src/pages/parade.html
@@ -83,7 +83,7 @@
          var roomsel = createDiv();
          roomsel.class("roomsel");
          var b = createButton("시작하기 Start!", 1);
-         var d = createDiv("흐름을&nbsp; 향하여&nbsp; 걷는 &nbsp;&nbsp;Walking towards the Flow");
+         var d = createDiv("<a href='/entry'>흐름을&nbsp; 향하여&nbsp; 걷는 &nbsp;&nbsp;Walking towards the Flow</a>");
          d.class("title");
          b.mouseClicked(function() {
            silence.start();
@@ -136,17 +136,17 @@
      socket.on("post", async function(post) {
 
        console.log(post);
-       var resp = await new Promise((resolve, reject) => {
+       var list = await new Promise((resolve, reject) => {
          loadJSON("/entries", (json) => resolve(json));
        })
-       console.log(resp.list);
+       console.log(list);
 
        // var object = post.object;
        var object = {
          "id": 1,
          "type": "abc",
-         "src": "https://p.dianaband.info/public/sound-parade/" + resp.list[post] + "/pixels.png",
-         "audio": "https://p.dianaband.info/public/sound-parade/" + resp.list[post] + "/audio.mp3",
+         "src": "https://p.dianaband.info/public/sound-parade/" + list[post] + "/pixels.png",
+         "audio": "https://p.dianaband.info/public/sound-parade/" + list[post] + "/audio.mp3",
          "alt": "알트",
          "size": {
            "base": 40,
diff --git a/src/pages/preview.html b/src/pages/preview.html
new file mode 100644
index 0000000..f43f471
--- /dev/null
+++ b/src/pages/preview.html
@@ -0,0 +1,375 @@
+<!DOCTYPE html>
+<html>
+
+  <head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
+    <title>흐름을 향하여 걷는</title>
+    <link rel="stylesheet" href="/default.css" />
+    <style>
+     html,
+     body {
+       overflow: hidden;
+     }
+    </style>
+    <script src="/js/p5-v1.1.9.min.js"></script>
+    <script src="/js/socket-v2.3.0.io.slim.js"></script>
+    <script src="/js/Tone-14.8.36.min.js"></script>
+    <link rel="preconnect" href="https://fonts.googleapis.com">
+    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
+    <link href="https://fonts.googleapis.com/css2?family=Noto+Sans+KR:wght@500&display=swap" rel="stylesheet" />
+  </head>
+
+  <body>
+    <div class="bg"></div>
+    <div class="content">
+    </div>
+    <script>
+     // // force https
+     // var http_confirm = location.href.split(":")[0];
+     // if (http_confirm == "http") {
+     //   window.location.replace("https://" + location.host);
+     // }
+
+     //--> https://gist.github.com/mudge/5830382#gistcomment-3398873 + modified trigger to accentp an arg.
+     function EventEmitter() {
+       const eventRegister = {};
+
+       const on = (name, fn) => {
+         if (!eventRegister[name]) eventRegister[name] = [];
+         eventRegister[name].push(fn);
+       }
+
+       const trigger = (name, arg = undefined) => {
+         if (!eventRegister[name]) return false;
+         eventRegister[name].forEach((fn) => fn.call(this, arg));
+       }
+
+       const off = (name, fn) => {
+         if (eventRegister[name]) {
+           const index = eventRegister[name].indexOf(fn);
+           if (index >= 0) eventRegister[name].splice(index, 1);
+         }
+       }
+
+       return {
+         on, trigger, off
+       }
+     }
+
+     //get preview target foldername
+     var foldername = "";
+     var urlparts = window.location.pathname.replace(/\/\s*$/,'').split('/');
+     foldername = urlparts[2]; // the server's route will guarantee urlparts[2] existence.
+     console.log(foldername);
+
+     var playing = true;
+
+     //set-up a preview stage
+     async function orchestra() {
+
+       //collect info.
+       var entries = await new Promise(async (resolve, reject) => resolve((await fetch("/entries")).json()));
+       var fields = await new Promise(async (resolve, reject) => resolve((await fetch("/fields")).json()));
+       var group = fields[entries.findIndex((e) => e == foldername)].group;
+       var members = fields.filter(obj => obj.group == group);
+       var midx = members.findIndex((e) => e.foldername == foldername);
+       //
+       function mtrig(m) {
+         //
+         m = m % members.length;
+         //
+         var idx = entries.findIndex((e) => e == members[m].foldername);
+         if (idx >= 0) socket.trigger('post', idx);
+       }
+
+       //now, let's orchestrate!
+       var time = 0;
+       Tone.Transport.schedule((t) => mtrig(midx - 1), time);
+       time = time + 12 + Math.random()*(4);
+       console.log(time);
+       Tone.Transport.schedule((t) => mtrig(midx), time);
+       time = time + 16 + Math.random()*(4);
+       console.log(time);
+       Tone.Transport.schedule((t) => mtrig(midx + 1), time);
+       time = time + 5 + Math.random()*(4);
+       console.log(time);
+       Tone.Transport.schedule((t) => mtrig(midx + 2), time);
+       time = time + 5 + Math.random()*(4);
+       console.log(time);
+       Tone.Transport.schedule((t) => mtrig(midx), time);
+       time = time + 70;
+       console.log(time);
+       Tone.Transport.schedule((t) => {
+         playing = false;
+       });
+       //
+       Tone.Transport.start();
+       //
+     }
+
+     //
+     setTimeout(() => {
+       socket.trigger('connect');
+     }, 100);
+
+     //
+     //var socket = io(location.host);
+     var socket = new EventEmitter();
+     var n = 0;
+     var fr = 20;
+     var arr = [];
+     var looper;
+     var score;
+     var logo;
+     var silence;
+     var clap;
+
+     //promisify -> new Tone.Player
+     function AudioImport(url) {
+       return new Promise((resolve, reject) => {
+         var audio = new Tone.Player(url, () => resolve(audio));
+       });
+     }
+
+     async function setup() {
+       noCanvas();
+       if (windowWidth > 1500 && windowWidth > windowHeight) {
+         fr = 30;
+       } else {
+         fr = 20;
+       }
+       frameRate(fr);
+
+       //p5 'draw()' doesn't work if user is not looking at the tab.
+       noLoop();
+       // --> use custom looper.
+     }
+
+     //
+     var myroom = -1;
+     var intro;
+     var ready;
+     //
+     socket.on("connect", async function() {
+       console.log("connected!");
+
+       //
+       silence = (await AudioImport("/audio/_silence.wav")).toDestination();
+       clap = (await AudioImport("/audio/clap01.mp3")).toDestination();
+
+       //TESTING... fixed to room 1.
+       // myroom = 1;
+
+       if (myroom == -1 && selectAll(".roomsel").length == 0) {
+         //initial connection -> ask the room number.
+
+         var roomsel = createDiv();
+         roomsel.class("roomsel");
+         var b = createButton("미리보기 Preview!", 1);
+         var d = createDiv("흐름을&nbsp; 향하여&nbsp; 걷는 &nbsp;&nbsp;Walking towards the Flow");
+         d.class("title");
+         b.mouseClicked(function() {
+           silence.start();
+           //clap.start();
+           orchestra();
+
+           setTimeout(() => {
+             selectAll(".roomsel").forEach(item => {
+               item.remove();
+               // 1 second popup '.intro' div
+               intro = createDiv(
+                 "미리보기<br>«흐름을 향하여 걷는»은 온라인 공간에 소리의 행렬을 만드는 사운드 퍼레이드입니다. 누구나 참여할 수 있는 이 퍼레이드는 여러분이 보내주시는 소리가 모여 만들어집니다.<br>소리가 들리지 않는다면, 볼륨을 확인해주시고, 스마트폰 환경에서는 진동해제해주세요. <br><br>Preview<br>«Walking Toward the Flow» is a sound parade that creates a procession of sounds in the online space. Anyone can participate. This parade is made by collecting the sounds you sent.<br>If there is no sound, check the volume and turn off the vibration in the smartphone environment."
+               );
+               intro.class("notice intro"); //-> fadeout & disapear by css animation style.
+             });
+           }, 1000);
+         });
+         roomsel.child(d);
+         roomsel.child(b);
+       } else {
+         //re-connection -> just connect to remembered room!
+         socket.emit("room", myroom, function(res) {
+           if (res) {
+             console.log("entered the room -> " + myroom);
+           } else {
+             console.log("rejected!");
+           }
+         });
+       }
+     });
+
+     //var fading_factor = 0.3; //30%
+     var fading_factor = 0.5; //50%
+     socket.on("post", async function(post) {
+
+       console.log(post);
+       var list = await new Promise((resolve, reject) => {
+         loadJSON("/entries", (json) => resolve(json));
+       })
+       console.log(list);
+
+       // var object = post.object;
+       var object = {
+         "id": 1,
+         "type": "abc",
+         "src": "https://p.dianaband.info/public/sound-parade/" + list[post] + "/pixels.png",
+         "audio": "https://p.dianaband.info/public/sound-parade/" + list[post] + "/audio.mp3",
+         "alt": "알트",
+         "size": {
+           "base": 40,
+           "random": 20
+         },
+         "y": {
+           "base": 20,
+           "random": 10
+         },
+         "showtime": 20000
+       };
+       console.log(object);
+
+       var img = createImg(object.src, object.alt, "", async function(im) {
+         //로딩이 끝나면, start!
+         var pv = new Tone.PanVol(0, -99).toDestination();
+         var snd = await AudioImport(object.audio); // NOTE: url with spaces didn't work here.
+         snd.connect(pv).start();
+         snd.loop = true;
+
+         //로딩이 끝나면, show!
+         im.show();
+
+         //그림의 크기와 초기 위치 ==> 가로 보기인 경우
+         var width = 0;
+         if (windowWidth > windowHeight) {
+
+           width = (windowHeight * (object.size.base * 1.4 + object.size.random * Math.random())) / 100; // 좀더 크게 + 40%  (ratio)
+           im.size(width, AUTO);
+
+           im.position(
+             windowWidth * (1 + fading_factor),
+             (windowHeight * (object.y.base + object.y.random * Math.random()) * 0.5) / 100 // 좀더 위로 위로 - 50%  (ratio)
+           );
+
+           //그림의 크기와 초기 위치 ==> 세로 보기인 경우
+         } else {
+
+           width = (windowHeight * (object.size.base + object.size.random * Math.random())) / 100; // json에서 정한 크기 그대로. (ratio)
+           im.size(width, AUTO);
+
+           im.position(
+             windowWidth * (1 + fading_factor),
+             (windowHeight * (object.y.base + object.y.random * Math.random())) / 100 // json에서 정한 위치 그대로. (ratio)
+           );
+         }
+
+         //추가 정보들
+         im.attribute("data-type", object.type);
+         im.attribute("data-showtime", object.showtime / 1000); //milli-sec. -> seconds.
+
+         //'아이콘' 들은 애니메이션을 시켜줘야 함...
+         if (object.type == "icon") {
+           //
+           im.class("rotate");
+           im.style("animation-duration", object.rotate + "s");
+           var orgs = im.style("transform-origin").split(" ");
+           var str = parseFloat(orgs[0]) + object.pivot.x + "px";
+           str = str + " " + parseFloat(orgs[1]) + object.pivot.y + "px";
+           im.style("transform-origin", str);
+           //
+         }
+
+         //로딩이 다 되면, rendering array에 추가.
+         var bundle = {
+           ref: object,
+           img: im,
+           sound: snd,
+           panvol: pv,
+           width: width
+         };
+         arr.push(bundle);
+       });
+
+       //첨에는 hide
+       img.hide();
+
+     });
+
+     //p5 'draw()' doesn't work if user is not looking at the tab.
+     Tone.Transport.scheduleRepeat((time) => {
+
+       //
+       for (var i = arr.length - 1; i >= 0; i -= 1) {
+         var bundle = arr[i];
+         var img = bundle.img;
+         var showtime = parseFloat(img.attribute("data-showtime"));
+         var type = img.attribute("data-type");
+         var x = img.position().x;
+         var y = img.position().y;
+         y = y + random(-1, 1);
+         x = x - windowWidth / (fr * showtime);
+
+         //
+         if (type == "icon") {
+           img.style("z-index", "-1");
+         }
+         3;
+
+         img.position(x, y);
+         var pan = (x / windowWidth) * 2 - 1;
+
+         //panning
+         var snd = bundle.sound;
+         var pv = bundle.panvol;
+         if (x >= -bundle.width && x < windowWidth) {
+           pan = ((x + bundle.width) / (windowWidth + bundle.width)) * 2 - 1;
+           pv.pan.value = pan;
+           pv.volume.value = 0;//(dB)
+         } else {
+           var range;
+           var knob;
+           if (x >= windowWidth) {
+             range = windowWidth * fading_factor
+             knob = x - windowWidth;
+             pv.pan.value = 1;
+             pv.volume.value = knob / range * -20;
+           } else if (x < -bundle.width) {
+             range = windowWidth * fading_factor
+             knob = (x + bundle.width) * -1;
+             pv.pan.value = -1;
+             pv.volume.value = knob / range * -20;
+           }
+         }
+
+         //remove with sound fade-out
+         var exit_x = -bundle.width - windowWidth * fading_factor;
+         if (x < exit_x) {
+           img.remove();
+           snd.stop();
+           delete snd;
+           delete pv;
+           arr.splice(i, 1);
+           if (arr.length == 0 && playing == false) {
+             setTimeout(() => {
+               createDiv("미리보기가 끝났습니다. <br>Preview is over.").class("notice").style('text-align', 'center');
+             }, 3000);
+           }
+         }
+       }
+       //
+
+     }, 1.0/fr);
+     Tone.Transport.start()
+
+     // function randomvoiceplay() {
+     //   (looper = function(timeout) {
+     //     setTimeout(function() {
+     //       voice[int(random(19))].play();
+     //       looper(random(8000, 12000));
+     //     }, timeout);
+     //   })(8000);
+     // }
+
+    </script>
+  </body>
+
+</html>