Lundahl Tube amplifier output transformer, LL1688

Tube Amplifier Output Transformer LL1688

LL1688 is an output transformer, designed primarily for 845 tube amplifiers, but the LL1688 is available with different core air-gaps for different types of output stages. The transformers are highly sectioned with harmonically sized sections, which results in a minimum leakage inductance. This, combined with a low capacitance coil winding technique results in a wide frequency range.

The primary winding can be tapped for 33% UL connection.
The transformers have a special audio C-core of our own production.
The transformers are unpotted, open frame type suitable for mounting inside an amplifier housing.

Pin spacing module: 5.08 mm (0.2")
Row spacing: 91 mm approx.
Weight: 4 kg
Turns ratio: 50 + 50 : 1 + 2 + 2 + 1 + 1 + 2 + 2 + 1

Frequency response, LL1688/70mA (source impedance 2.2k, load impedance 10 ohms. Primary winding is series, secondary winding alt. C. Secondary winding not grounded. Primary signal level approx 10V)
10 Hz 25kHz +0 / -1 dB
5Hz 33 kHz +0 / -3 dB