Rode NT1 5th Generation Mods
The 5th-generation Rode NT1 uses a transformerless circuit made of surface-mount components, and an edge-terminated capsule. It does not use the internal Rycote suspension debuted in the 3rd Generation (2013) model.
Circuit Mods for the NT1
Due to the use of surface-mount components in the 5th Generation NT1, there are no circuit mods that are feasible for DIY.
Capsule Replacement for the NT1
We have tested several capsules in this latest NT1. We do not recommend any capsules for this mic.
The 5th Gen NT1 mics we measured varied in response. Some were relatively neutral. Some were noticeably brighter; our subjective impression is that they sounded bright and thin in a way that would lead to harshness and sibilance.
Our RK-12 capsule has better bass response, and a smoother, more neutral top end than the brighter 5th Gen NT1 mics we measured.
If your 5th Gen NT1 seems bright, harsh, or sibilant, our best recommendation is that you return it, or sell it, then use the proceeds to buy a nicer microphone. The RK-12 would probably sound better, but we have not found that the 5th Gen NT1 circuit is so special that it merits an expensive capsule upgrade.
We recommend the RK-47 for older NT1 mics, but the 5th Gen model is a bad host for the RK-47 (or any other K47) because its circuit and/or acoustic design cause a sharp rolloff around 10kHz that makes K47 capsule sound muddy.
A Poor Platform for DIY Upgrades
If you are shopping for microphones for the purpose of upgrading them, we do not recommend the 5th Gen NT1. See this directory for models that have circuit upgrades and capsule upgrades available.
We have heard customers express desire for this mic's "low noise" circuitry. While low noise is an admirable characteristic, it is much less important than frequency response for most recording. Any competently designed and built large-diaphragm condenser is likely to have low self-noise, e.g. 12-14dBA. That's sufficiently low that you would not have a noise problem for any vocal or instrument recording.