All StringsTheory apps work offline and require no account to use core features. If you need help, we're here.
For questions, bug reports, feature requests, or license help — reach out anytime.
info@stringstheoryinv.comInventory, work order, and production management for repair shops, luthiers, and small manufacturers. Track inventory, manage repairs from intake to invoice, run COGS reports, design and print labels, and sync with Square, Shopify, and Google Sheets. Available as a subscription with a 7-day free trial.
Tube amp bias calculator, component calculators, chromatic tuner, string tension calculator, and tube/amp reference databases. A utility toolkit for tube amp builders, technicians, and guitar techs. Works entirely offline — no account required.
Tube amplifier circuit analysis toolkit with five integrated tools: Tonestack Calculator (Bode plots for 53 guitar amp tone circuits), PSU Designer (time-domain power supply simulation with 173 rectifier models), Load Lines (tube operating point analysis with Koren models), Tube Data (searchable database of 3,727 vacuum tubes with pinout diagrams), and Build Planner (transformer requirements calculator with 479 amplifier references). Works entirely offline — no account required.
No. All StringsTheory apps work fully offline. Some apps optionally check for announcements, but this never requires internet access and fails silently.
Tonestack configurations save and load as JSON files. PSU designs use the PSUD2-compatible .psu binary format.
No. All data is stored locally on your device. Nothing is uploaded or synced (unless you explicitly enable Cloud Sync in StringsTheory INV).
Tube specifications are sourced from manufacturer datasheets (RCA, Mullard, Philips, GE, Tung-Sol). Maximum filter capacitor ratings for rectifier tubes have been individually verified against original PDF datasheets. However, always cross-reference critical safety values against the original manufacturer datasheet for your specific tube.
Email info@stringstheoryinv.com — we read every message.