Buying a Used Lab.gruppen PLM 20K44 Amplifier: Inspection Checklist

A used Lab.gruppen PLM 20K44 is a four-channel touring amplifier with onboard Lake processing, so condition of both the power stage and DSP matters. Ask the seller for clear photos of the input/output panels, serial label, and any service history. Test every channel independently under load, not just at idle; listen for fan bearing noise, relay clicks, or channel imbalance. Confirm the Lake processing boots, that presets load, and that network ports communicate with your control software. Inspect for burnt smells, corrosion, bent rack ears, and evidence of liquid damage or previous repairs. Verify the mains voltage configuration matches your region, and request a load test if possible. Because used units may have been racked hard, check the power supply capacitors and output modules visually. Buy from a seller who can demonstrate functionality and provide honest disclosure of cosmetic and operational condition. Match the amplifier to your speaker loads before purchase.