πŸ”Œ
Amp & Speaker Matcher
What impedance is safe to run from my amp output?

Tell us your amp's output tap and we'll show you exactly which speaker impedances are safe, which are marginal, and which will damage your output transformer. The question everyone asks β€” answered clearly.

Your Amplifier
Output Transformer Taps Available on Your Amp
Select all taps your amp has β€” check the back panel for labelled output sockets
2Ξ©
4Ξ©
8Ξ©
16Ξ©

⚠ The Golden Rules of Speaker Impedance

πŸ”΄Never run a tube amp with no speaker connected. Without a load, the output transformer sees infinite impedance. Voltage spikes back through the primary winding and can destroy the transformer permanently β€” one of the most expensive repairs on a tube amp.
🟑Too low is safer than too high. A lower-than-rated impedance load causes higher current draw β€” the amp runs warm but usually survives. A higher-than-rated impedance causes voltage spikes β€” more likely to damage the output transformer.
🟒Use the closest available tap. If your load doesn't match perfectly, use the nearest tap. A 10–25% mismatch in a tube amp is generally tolerable. Beyond that, rewire your speakers or add/remove a cabinet.
πŸ”΅Tube amps are more tolerant than solid state. The output transformer provides some buffering. A 2:1 mismatch (e.g. 8Ξ© load on a 16Ξ© tap) is often acceptable short-term. A solid state amp in the same situation may blow immediately.
Impedance Safety Guide β€” Your Amp
Impedance Safety Matrix
Common Cabinet Configurations
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