Hammond 117K16 25V 16W Line Matching Transformer, 8 Ohm Speaker

The 117K16 is a 25 volt line matching audio transformer from the 117 Series (Audio Sound Distribution Line Matching). It couples a 8 Ω loudspeaker to the 25 V line output of a distribution amplifier, for use in audio sound distribution systems. It is the 25 V, 16 W model for 8 ohm speakers; the 117F16 is the 70 V equivalent.

The transformer is rated at 16 watts and offers 5 primary power taps — 16 W, 8 W, 4 W, 2 W, 1 W — marked in watts on the part, so installers can pick the tap that matches each speaker's power without calculation. The manufacturer notes that the total power requirements of the speakers should not exceed the rated power of each transformer or the rated power of the amplifier.

Typical performance from the 117K16 drawing: frequency response 100 Hz to 9 kHz (+2/-3 dB reference @ 1 kHz), distortion less than 2.0% at 100 Hz at maximum power, insertion loss under 2 dB, dielectric strength 1500 VRMS and a temperature range of -40 to 105°C. DC resistance is 10.2 Ω (COM - 1 W) on the primary and 0.44 Ω on the input (speaker) winding. Dielectric strength is rated at 1500 VRMS.

Mounting is horizontal on a channel bracket with two 0.187" diameter holes on 3.13 in (80 mm) centers. Overall dimensions in the series table are A 3.69 in (94 mm), B 2.00 in (51 mm), C 2.31 in (59 mm) and D 3.13 in (80 mm). All connections are solder lugs that are also suitable for slip-on jumper connections. Listed weight is 1.5 lbs (shipping weight 1.5 lbs (0.68 kg)), and the part is RoHS and REACH compliant.