GPU vs CPU: What Is Faster for Training Your Own NAM Model?

Capturing your own amp is the most exciting part of NAM. The recording takes minutes; the training can take minutes or hours depending on your hardware. Here is what actually makes the difference.

Create NAM Hub team · October 2, 2026 · 6 min read

How NAM training works, in one paragraph

You play a standard training signal (a special audio file provided by the NAM project) through your amp or pedal and record the result — this is called reamping. The trainer then teaches a neural network to turn the dry signal into the recorded one. Training repeats the same calculation many times over the audio ("epochs"), and that is the part that needs computing power.

The short answer

  • NVIDIA GPU (CUDA): the fastest common option. A standard model with default settings usually finishes in minutes to roughly half an hour, depending on the card.
  • Free cloud GPU (e.g. Google Colab): no special hardware needed — you upload your files and train in the browser. Speed depends on the GPU you are given and on availability.
  • Apple Silicon Mac: can train locally; usually slower than a dedicated NVIDIA card but much faster than an older CPU.
  • CPU only: it works, but it is slow — often hours for a standard model.
Bottom line: you do not need to buy a graphics card to make your first captures. Free cloud training is enough to learn. A GPU becomes worth it when you capture many amps or settings.

What affects training time

  • Model size. Standard models take longest; Lite, Feather and Nano train faster and run lighter, at a small cost in accuracy.
  • Number of epochs. More epochs usually mean a slightly better fit and a longer wait. Default settings are a sensible starting point.
  • Hardware. GPU memory and generation matter more than the CPU when training on a GPU.
  • Other programs. Close games, browsers with many tabs and video editors while training locally.

Local GPU vs cloud: pros and cons

Local NVIDIA GPUFree cloud notebookCPU only
SpeedFastVariesSlow
CostHardware you may already ownFree (with limits)Free
SetupInstall drivers and trainerBrowser onlyInstall trainer
Best forMany capturesFirst capturesOccasional, patient users

Tips to get a good model faster

  1. Record cleanly. A good recording matters more than training time: correct levels, no clipping, no extra noise, and the reamped file perfectly aligned with the training signal.
  2. Use the standard training file and 48 kHz, exactly as the NAM project recommends.
  3. Start with default settings. Change the architecture or epochs only if you have a reason.
  4. Check the result by ear, not only by ESR. Compare the model with the real amp at the same volume.
  5. Batch your work. Record several settings in one session, then train them one after another.

Do you need a GPU to play NAM?

No. Playing through a model runs on the CPU in real time; the graphics card is only used for training. For smooth playback, see our latency guide.

Want to try capturing? Read Create your own NAM step by step.

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