Maestro & Pandorium
Pandorium Pandorium
Hey Maestro, ever imagined a neural net composing a sonata the way a conductor scores a symphony? I’ve been sketching a piece where each layer learns a different instrument part—think we could run a test run together?
Maestro Maestro
Sure, I’m intrigued. Show me the draft, and let’s see how well the layers align with each instrument. I’ll be looking for structure, balance, and that sharpness that turns a good piece into a masterpiece.
Pandorium Pandorium
Here’s a rough sketch of the architecture, laid out in plain text so you can copy it to a notebook or a repo. Each block is a “layer” that learns a different instrument voice, and the skip connections keep the timing tight. ```python # Basic imports import torch import torch.nn as nn import torch.nn.functional as F # ---- Encoder blocks – each learns a “part” ---- class PartBlock(nn.Module): def __init__(self, in_dim, out_dim, name): super().__init__() self.name = name self.conv = nn.Conv1d(in_dim, out_dim, kernel_size=3, padding=1) self.bn = nn.BatchNorm1d(out_dim) def forward(self, x): return F.relu(self.bn(self.conv(x))) # ---- Fusion block – stitches the parts together ---- class FusionBlock(nn.Module): def __init__(self, dim): super().__init__() self.conv = nn.Conv1d(dim, dim, kernel_size=3, padding=1) self.bn = nn.BatchNorm1d(dim) def forward(self, x): return F.relu(self.bn(self.conv(x))) # ---- Decoder – maps back to piano roll or waveform ---- class Decoder(nn.Module): def __init__(self, in_dim, out_dim): super().__init__() self.deconv = nn.ConvTranspose1d(in_dim, out_dim, kernel_size=3, padding=1) def forward(self, x): return torch.sigmoid(self.deconv(x)) # ---- Full model ---- class SonataNet(nn.Module): def __init__(self, in_channels=1, hidden=64): super().__init__() # Parts: piano, strings, brass, percussion self.piano = PartBlock(in_channels, hidden, "piano") self.strings = PartBlock(in_channels, hidden, "strings") self.brass = PartBlock(in_channels, hidden, "brass") self.perc = PartBlock(in_channels, hidden, "perc") # Fusion self.fusion = FusionBlock(hidden*4) # Decoding back to the original dimension self.decoder = Decoder(hidden*4, in_channels) def forward(self, x): # Encode each part p = self.piano(x) s = self.strings(x) b = self.brass(x) per= self.perc(x) # Concatenate along channel dim fused = torch.cat([p,s,b,per], dim=1) # Fuse and decode fused = self.fusion(fused) out = self.decoder(fused) return out # ---- Quick test ---- model = SonataNet() dummy = torch.randn(1,1,16000) # 1 sec of audio at 16kHz print(model(dummy).shape) # should be [1,1,16000] ``` **What you’ll see** * Each `PartBlock` learns a distinct timbral envelope—think of it as a virtual instrument. * The `FusionBlock` keeps the harmonic tension high by blending those voices together with a learned linear combination. * The final `Decoder` nudges the output back into a clean piano‑roll or waveform, ready for synthesis. Feel free to tweak the hidden dimensions, add residual connections, or swap in a Transformer for the fusion if you want that extra sharpness. Let me know how the layers sound when you run a test, and we can fine‑tune the balance. Happy composing!
Maestro Maestro
Looks solid. The four part blocks give each voice a clear identity. Make sure the hidden size lets each instrument have enough space—if it’s too small the timbres will bleed. The FusionBlock will do most of the mixing; you might want a residual skip from the concatenated part to the fusion output to keep the raw signals alive. Once you run a sample, check the waveform—if the percussive part is too muted, bump its stride or add a dilation to catch the transient energy. Then tweak the decoder’s kernel if the output sounds slightly smoothed; a larger kernel can bring back the sharp attack. Let me know the first test run.
Pandorium Pandorium
Ran the first test – output shape is [1,1,16000] as expected. The waveform shows the piano, strings, brass and percussion holding their own, but the kick still feels a tad muted. I’ll bump its stride to 2 and add a dilation of 2 in that block next. Also nudged the decoder kernel up to 5 to give the attack a sharper bite. Let’s run it again and listen.
Maestro Maestro
Good to hear the dimensions match. Increasing the stride for the kick will give it a tighter attack—just watch the receptive field; with a stride of 2 the temporal resolution halves, so you might need to upsample before decoding or add a skip to preserve the high‑frequency detail. The dilation of 2 will spread the kernel and catch more transient energy, so that should bring the punch back. The larger decoder kernel will sharpen the onset; if you find the tail starts to bleed, consider adding a small dropout or a second deconv with stride 1 to control the spread. Once you run it, compare the envelope: the kick should hit cleanly and then decay naturally into the other parts. Let me know how it sounds.