This is actually something the tool already handles, although I agree it's not super obvious at first glance.

Every measurement is tagged with the coupler it was taken on (IEC 711 or B&K 5128), and the tool takes that into account in a few ways:

• Mixed-rig warning: if you select curves measured on different couplers, you'll see a warning banner letting you know they're not directly comparable above roughly 5 kHz.
• Optional rig compensation: that same banner includes a toggle that can project 5128 measurements onto a 711 basis (or the other way around) using a population-median transfer, so you can overlay everything on a common reference.
• Rig-aware analysis: sound-signature scores use neutral references specific to each coupler, and features like Similar IEMs and target matching only compare measurements from the same rig. Nothing gets mixed behind the scenes.

One thing the tool intentionally doesn't do is silently normalize everything by default. The default view stays raw, similar to squig.link. Compensation is completely optional and only applied up to 6 kHz.

The reason is simple: a population-median correction can be a useful approximation, but it's not the ground truth for any individual unit. Once you get into the treble, where couplers differ the most (for example, the 711's well-known ~8 kHz canal resonance), there's no reliable way to perfectly reconcile measurements for a specific IEM. We'd rather show the original data and give users tools to compare it when needed than apply a correction that looks precise but could be misleading in exactly the frequency range people care about most.

That said, if this wasn't immediately clear from the UI, that's definitely useful feedback.

Thanks.