In this article
Updated September 18, 2026. Chaos Audio makes Nimbus. This comparison uses published specifications for Nimbus and Positive Grid Spark 2 to explain their workflows. Nimbus is currently available for preorder.
Nimbus and Spark 2 at a glance
| Feature | Chaos Audio Nimbus | Positive Grid Spark 2 |
|---|---|---|
| Amplifier and speakers | 100W stereo; custom PowerBass collaboration speakers angled at 15° | 50W RMS; two 4-inch full-range speakers |
| Inputs | Two XLR / ¼-inch combo inputs | One ¼-inch instrument input |
| Sound library | Compatible NAM captures, AI-generated effects and pre-made effects | HD amp modeling, built-in effects and ToneCloud presets |
| USB recording | USB-C audio interface | USB-C audio interface |
| Practice features | Bluetooth backing tracks and customizable effect chains | Bluetooth audio, Simple Looper and Creative Groove Looper |
Choose the workflow you will use
Spark 2 provides a practice-focused system with app-based sounds, looping and optional battery operation. Its published library includes 33 amp models and 43 effects, with shared presets available through ToneCloud. If a ready-made practice setup is your priority, those tools are directly relevant.
Nimbus emphasizes flexible sound creation. It runs NAM natively in A2-Lite mode without format conversion, using one compatible NAM model at a time alongside effects and IRs. Native NAM replaces the AIDA-X implementation described in the original version of this article.
Nimbus includes 30 FX Builder 2.0 Builds per month; creation and refinements use that allowance. Describe an effect, audition it, request changes, and install it on the amp, where the finished effect processes your instrument locally. That lets you develop a useful personal sound, such as a delay whose repeats stay darker behind the dry playing.
Inputs and recording
The second combo input is a practical Nimbus difference for two instruments or a guitar-and-microphone setup. Both amps offer USB-C recording, so USB audio by itself is not a reason to choose one over the other. Check the current manuals for channel routing, computer compatibility and your intended microphone setup.
Nimbus supports 1024-sample cabinet IRs and 16GB onboard storage, with no old ten-IR slot limit. That gives you room to organize a cabinet library alongside your effects.
Power does not settle the comparison
The manufacturers specify 100W stereo for Nimbus and 50W RMS for Spark 2. Those numbers do not establish a two-to-one loudness difference or guarantee performance with a loud drummer. Speaker efficiency, room acoustics and placement all influence what you hear. Choose your monitoring setup for the actual room and volume you need.
Budget, portability and delivery
Nimbus is listed at $599 USD for preorder as of this update. Check the Nimbus page for the current delivery estimate. Spark 2 pricing and promotions change, so use Positive Grid's current listing for the configuration you want, including any battery or foot controller.
Choose Nimbus when two combo inputs, stereo playback, and creating a personal collection of compatible captures and effects are central to your setup, and its delivery timeline works for you. Choose Spark 2 when its integrated practice tools and optional battery suit the way you play. Both can record over USB; decide which everyday workflow you want rather than using output-power figures as a sound-quality ranking.
Sources: Current Nimbus specifications; Positive Grid Spark 2 product information; Spark 2 user manual.
