diff --git a/packages/web/public/sounds/stream_ended.ogg b/packages/web/public/sounds/stream_ended.ogg
index e2cdcd83..201ac1d3 100644
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diff --git a/packages/web/public/sounds/stream_started.ogg b/packages/web/public/sounds/stream_started.ogg
index 55530cc4..d885c530 100644
Binary files a/packages/web/public/sounds/stream_started.ogg and b/packages/web/public/sounds/stream_started.ogg differ
diff --git a/packages/web/public/sounds/stream_user_joined.ogg b/packages/web/public/sounds/stream_user_joined.ogg
index b6806e8e..026c219a 100644
Binary files a/packages/web/public/sounds/stream_user_joined.ogg and b/packages/web/public/sounds/stream_user_joined.ogg differ
diff --git a/packages/web/public/sounds/stream_user_left.ogg b/packages/web/public/sounds/stream_user_left.ogg
index b333375f..ae16545b 100644
Binary files a/packages/web/public/sounds/stream_user_left.ogg and b/packages/web/public/sounds/stream_user_left.ogg differ
diff --git a/packages/web/public/sounds/user_join.ogg b/packages/web/public/sounds/user_join.ogg
index 9bd924dd..2d5d5dd6 100644
Binary files a/packages/web/public/sounds/user_join.ogg and b/packages/web/public/sounds/user_join.ogg differ
diff --git a/packages/web/public/sounds/user_leave.ogg b/packages/web/public/sounds/user_leave.ogg
index 8305e422..359ee0ca 100644
Binary files a/packages/web/public/sounds/user_leave.ogg and b/packages/web/public/sounds/user_leave.ogg differ
diff --git a/tools/sfx/README.md b/tools/sfx/README.md
new file mode 100644
index 00000000..acd367a3
--- /dev/null
+++ b/tools/sfx/README.md
@@ -0,0 +1,32 @@
+# Geradores dos efeitos sonoros
+
+Os `.ogg` em `packages/web/public/sounds/` para call e transmissão são
+sintetizados por estes scripts — nenhum arquivo de terceiros, nenhuma questão
+de licença num repositório público.
+
+Os parâmetros não foram escolhidos a gosto: saíram da **medição** de dois sons
+de referência fornecidos pelo dono da instância (análise de envelope, picos
+espectrais e tempo de decaimento). O timbre resultante é fundamental + oitava
+quase na mesma intensidade, com pouco acima disso:
+
+| Harmônico | Proporção medida |
+|---|---|
+| 1x (fundamental) | 1.00 |
+| 2x (oitava)      | 0.85 |
+| 3x               | 0.10 |
+| 4x               | 0.02 |
+
+Decaimento a 1/e: ~0,19 s. Sem reverberação.
+
+| Script | Gera | Notas |
+|---|---|---|
+| `build.py`    | `user_join`, `user_leave` | C4→G4 subindo / D4→G3 descendo |
+| `stream.py`   | `stream_user_joined`, `stream_user_left` | nota única (G4 / G3), ~55% do volume |
+| `started4.py` | `stream_started` | acorde de dó + golpe grave + sopro de ar |
+| `ended.py`    | `stream_ended` | arpejo descendo, resolve na raiz grave |
+
+Para regerar: `python3 <script>.py` produz `.wav`, depois converter com
+`ffmpeg -i X.wav -c:a libvorbis -q:a 5 -ar 48000 X.ogg`.
+
+Ajustes comuns: `HARM` muda o timbre, `tau` a duração, `step` a velocidade do
+arpejo, e o alvo em `write()` o volume (pico RMS).
diff --git a/tools/sfx/build.py b/tools/sfx/build.py
new file mode 100644
index 00000000..920e93cf
--- /dev/null
+++ b/tools/sfx/build.py
@@ -0,0 +1,47 @@
+import math, wave, struct
+SR=48000
+# Proporcoes medidas nas referencias: fundamental, oitava, 3o, 4o
+HARM=(1.00, 0.85, 0.10, 0.02)
+TAU=0.19          # decaimento a 1/e medido
+ATTACK=0.004
+
+def note(f, dur):
+    n=int(SR*dur); o=[]
+    for i in range(n):
+        t=i/SR
+        s=sum(a*math.sin(2*math.pi*f*(k+1)*t) for k,a in enumerate(HARM))
+        o.append(s*min(1.0,t/ATTACK)*math.exp(-t/TAU))
+    return o
+
+def mix(layers,total):
+    b=[0.0]*total
+    for off,s in layers:
+        for i,v in enumerate(s):
+            if off+i<total: b[off+i]+=v
+    return b
+
+def peak_rms(x, win=int(SR*0.01)):
+    best=0.0
+    for i in range(0,len(x)-win,win):
+        seg=x[i:i+win]
+        best=max(best, math.sqrt(sum(v*v for v in seg)/len(seg)))
+    return best
+
+def write(name, buf, target_rms):
+    cur=peak_rms(buf)
+    g=target_rms/max(1e-9,cur)
+    # nao deixa estourar mesmo casando o volume da referencia
+    pk=max(abs(s*g) for s in buf)
+    if pk>0.97: g*=0.97/pk
+    with wave.open(name,'w') as w:
+        w.setnchannels(1); w.setsampwidth(2); w.setframerate(SR)
+        w.writeframes(b''.join(struct.pack('<h',int(max(-1,min(1,s*g))*32767)) for s in buf))
+    print(f"{name}: pico RMS {peak_rms([s*g for s in buf]):.3f}, {len(buf)/SR:.2f}s")
+
+C4,D4,G3,G4 = 261.63, 293.66, 196.00, 392.00
+GAP=int(SR*0.10)   # 100ms entre as notas, medido
+
+# join: quinta subindo — mesmas notas da referencia
+write('user_join.wav',  mix([(0,note(C4,0.55)),(GAP,note(G4,0.55))], int(SR*0.62)), 0.365)
+# leave: quinta descendo
+write('user_leave.wav', mix([(0,note(D4,0.55)),(GAP,note(G3,0.55))], int(SR*0.62)), 0.440)
diff --git a/tools/sfx/ended.py b/tools/sfx/ended.py
new file mode 100644
index 00000000..40cabffb
--- /dev/null
+++ b/tools/sfx/ended.py
@@ -0,0 +1,53 @@
+import math, wave, struct
+SR=48000
+HARM=(1.00, 0.85, 0.10, 0.02)
+
+def note(f, dur, tau, amp=1.0):
+    n=int(SR*dur); o=[]
+    for i in range(n):
+        t=i/SR
+        s=sum(a*math.sin(2*math.pi*f*(k+1)*t) for k,a in enumerate(HARM))
+        o.append(s*amp*min(1.0,t/0.004)*math.exp(-t/tau))
+    return o
+
+def thump(f, dur, amp):
+    n=int(SR*dur); o=[]; ph=0.0
+    for i in range(n):
+        t=i/SR
+        ph += 2*math.pi*(f*(1+1.2*math.exp(-t/0.02)))/SR
+        o.append(math.sin(ph)*amp*math.exp(-t/(dur*0.30)))
+    return o
+
+def mix(layers,total):
+    b=[0.0]*total
+    for off,s in layers:
+        for i,v in enumerate(s):
+            if off+i<total: b[off+i]+=v
+    return b
+
+def peak_rms(x, win=int(SR*0.01)):
+    return max(math.sqrt(sum(v*v for v in x[i:i+win])/win) for i in range(0,len(x)-win,win))
+
+def write(name, buf, target):
+    g=target/max(1e-9,peak_rms(buf))
+    pk=max(abs(s*g) for s in buf)
+    if pk>0.97: g*=0.97/pk
+    with wave.open(name,'w') as w:
+        w.setnchannels(1); w.setsampwidth(2); w.setframerate(SR)
+        w.writeframes(b''.join(struct.pack('<h',int(max(-1,min(1,s*g))*32767)) for s in buf))
+    print(f"{name}: pico RMS {peak_rms([s*g for s in buf]):.3f}, {len(buf)/SR:.2f}s")
+
+C3,C4,E4,G4,C5 = 130.81,261.63,329.63,392.00,523.25
+step=int(SR*0.033)
+
+# Espelho do inicio: o arpejo DESCE e resolve na raiz grave, que entra por
+# ultimo. Sem o sopro de ar — brilho sugere chegada, nao encerramento.
+# Mais curto e mais baixo: encerrar merece menos destaque que comecar.
+write('stream_ended.wav', mix([
+    (0,      note(C5, 0.42, 0.15, 0.70)),
+    (step,   note(G4, 0.44, 0.16)),
+    (2*step, note(E4, 0.46, 0.17)),
+    (3*step, note(C4, 0.48, 0.19)),
+    (3*step, note(C3, 0.50, 0.21, 0.80)),
+    (3*step, thump(85, 0.13, 0.40)),
+], int(SR*0.55)), 0.34)
diff --git a/tools/sfx/started4.py b/tools/sfx/started4.py
new file mode 100644
index 00000000..4f0d9e7e
--- /dev/null
+++ b/tools/sfx/started4.py
@@ -0,0 +1,65 @@
+import math, random, wave, struct
+SR=48000; random.seed(11)
+HARM=(1.00, 0.85, 0.10, 0.02)
+
+def note(f, dur, tau, amp=1.0):
+    n=int(SR*dur); o=[]
+    for i in range(n):
+        t=i/SR
+        s=sum(a*math.sin(2*math.pi*f*(k+1)*t) for k,a in enumerate(HARM))
+        o.append(s*amp*min(1.0,t/0.004)*math.exp(-t/tau))
+    return o
+
+def thump(f, dur, amp):
+    """Instrumento 2: golpe grave com queda de tom. Da impacto no ataque e
+    morre em 90ms — engorda sem alongar."""
+    n=int(SR*dur); o=[]; ph=0.0
+    for i in range(n):
+        t=i/SR
+        ph += 2*math.pi*(f*(1+1.2*math.exp(-t/0.02)))/SR
+        o.append(math.sin(ph)*amp*math.exp(-t/(dur*0.30)))
+    return o
+
+def air(dur, amp, cutoff=5000):
+    """Instrumento 3: sopro curto de ruido filtrado. Brilho no inicio, sem cauda."""
+    n=int(SR*dur)
+    y=0.0; a=1-math.exp(-2*math.pi*cutoff/SR); o=[]
+    for i in range(n):
+        t=i/SR
+        y += a*(random.uniform(-1,1)-y)
+        o.append(y*amp*min(1.0,t/0.008)*math.exp(-t/(dur*0.22)))
+    return o
+
+def mix(layers,total):
+    b=[0.0]*total
+    for off,s in layers:
+        for i,v in enumerate(s):
+            if off+i<total: b[off+i]+=v
+    return b
+
+def peak_rms(x, win=int(SR*0.01)):
+    return max(math.sqrt(sum(v*v for v in x[i:i+win])/win) for i in range(0,len(x)-win,win))
+
+def write(name, buf, target):
+    g=target/max(1e-9,peak_rms(buf))
+    pk=max(abs(s*g) for s in buf)
+    if pk>0.97: g*=0.97/pk
+    with wave.open(name,'w') as w:
+        w.setnchannels(1); w.setsampwidth(2); w.setframerate(SR)
+        w.writeframes(b''.join(struct.pack('<h',int(max(-1,min(1,s*g))*32767)) for s in buf))
+    print(f"{name}: pico RMS {peak_rms([s*g for s in buf]):.3f}, {len(buf)/SR:.2f}s")
+
+C3,G3,C4,E4,G4,C5 = 130.81,196.00,261.63,329.63,392.00,523.25
+step=int(SR*0.033)   # arpejo bem rapido: acorde montado em 100ms
+
+# Decaimentos ~metade dos anteriores (0.20 vs 0.38). Total 0.62s vs 1.08s.
+write('stream_started.wav', mix([
+    (0,      thump(85, 0.14, 0.55)),        # impacto
+    (0,      air(0.13, 0.16)),              # brilho
+    (0,      note(C3, 0.60, 0.22, 0.80)),
+    (0,      note(G3, 0.58, 0.20, 0.45)),
+    (0,      note(C4, 0.56, 0.20)),
+    (step,   note(E4, 0.54, 0.19)),
+    (2*step, note(G4, 0.52, 0.18)),
+    (3*step, note(C5, 0.50, 0.16, 0.70)),
+], int(SR*0.62)), 0.42)
diff --git a/tools/sfx/stream.py b/tools/sfx/stream.py
new file mode 100644
index 00000000..149b2e9d
--- /dev/null
+++ b/tools/sfx/stream.py
@@ -0,0 +1,31 @@
+import math, wave, struct
+SR=48000
+HARM=(1.00, 0.85, 0.10, 0.02)   # mesmo timbre medido nas referencias
+ATTACK=0.004
+
+def note(f, dur, tau):
+    n=int(SR*dur); o=[]
+    for i in range(n):
+        t=i/SR
+        s=sum(a*math.sin(2*math.pi*f*(k+1)*t) for k,a in enumerate(HARM))
+        o.append(s*min(1.0,t/ATTACK)*math.exp(-t/tau))
+    return o
+
+def peak_rms(x, win=int(SR*0.01)):
+    return max(math.sqrt(sum(v*v for v in x[i:i+win])/win)
+               for i in range(0,len(x)-win,win))
+
+def write(name, buf, target):
+    g=target/max(1e-9,peak_rms(buf))
+    pk=max(abs(s*g) for s in buf)
+    if pk>0.97: g*=0.97/pk
+    with wave.open(name,'w') as w:
+        w.setnchannels(1); w.setsampwidth(2); w.setframerate(SR)
+        w.writeframes(b''.join(struct.pack('<h',int(max(-1,min(1,s*g))*32767)) for s in buf))
+    print(f"{name}: pico RMS {peak_rms([s*g for s in buf]):.3f}, {len(buf)/SR:.2f}s")
+
+G3, G4 = 196.00, 392.00
+# Decaimento mais curto (0.13 vs 0.19) e volume ~55% do som de call:
+# entrar/sair da tela dispara muitas vezes durante uma transmissao.
+write('stream_user_joined.wav', note(G4, 0.42, 0.13), 0.20)
+write('stream_user_left.wav',   note(G3, 0.42, 0.13), 0.20)