Speaker Thump on switching on

[tiger449]

I recently bought a s/h ROTEL RA-840 and matching tuner. Everything fine except for a significant speaker excursion on switching on. OK, I only need to incorporate a decent size electrolytic cap on one of the speaker lines if the DC is present long term, also a double pole switch so as I manually switch the speakers on a few seconds after switch on. My other amp has built-in anti-thump circuitry which delays application of power to the amplifier rails until the reservoir electrolytics have been fully charged.

Is feeling a significant draught from the speakers a common feature on this relatively old technology? Will check with my DMM for long term DC on speaker terminals.