Martin Logan Grotto
Price trend
18 months of data shown — Listing Comps build richer history as transactions accumulate.
Sold or Listed Prices
8 market transactions via web search — not HiFi Registry sales.
Understanding the market
Half of recorded transactions fall between $350 and $450. The full range is tight — lowest to highest is only 1.7×, which suggests these units trade in a well-established band and condition moves price less than it does for many models.
Prices over the last twelve months have held roughly flat, averaging $350 across 3 recorded sales.
What buyers should know
Powered subwoofers fail at the amplifier module far more often than at the driver. Ask whether the amp has been serviced or replaced, and confirm the unit powers up and passes low-frequency material without distress. Shipping weight makes these expensive to move.
This range reflects 8 recorded sales, compiled from publicly listed and completed sales elsewhere on the used market, not from HiFi Registry transactions. That is enough to establish a working range, but not enough to be precise — treat it as a guide rather than an appraisal.