1638SEA

Overview

The Hammond Manufacturing 1638SEA is a single-ended tube output transformer designed for high-fidelity audio applications. It features a primary impedance of 10,000 ohms and supports secondary impedances of 4, 8, and 16 ohms. The unit delivers a power rating of 30 watts with a current capacity of 90 mA. Operating within a frequency range of 20 Hz to 20 kHz, it includes a 40% screen tap to facilitate Ultra-Linear or tetrode/pentode operation.

Feature Summary

• Single-ended design optimized for high-fidelity audio signal transmission
• Integrated 40% screen tap enabling flexible Ultra-Linear or tetrode/pentode configurations
• Multi-tap secondary winding supporting standard speaker impedances

Applications

• High-fidelity tube amplifier construction
• Audio equipment requiring single-ended output stages
• Custom audio transformer integration

Procurement Notes

Verify the specific secondary impedance configuration required for your load against the available 4, 8, and 16 ohm options. Confirm that the 10,000 ohm primary matches your vacuum tube plate-to-plate requirements. Ensure the chassis mounting style aligns with your enclosure design specifications before finalizing the order.

Selection Notes

Select this model when a single-ended topology is mandated for the audio circuit. The 30-watt rating suits moderate-power tube amplifiers. Consider the included 40% screen tap if ultra-linear performance characteristics are desired for the specific tube type in use. Verify compatibility with the target frequency response requirements.

Part Context

This component belongs to the Hammond Tube Output Transformer series (1627-1642), which covers power ratings from 25 to 75 watts. The 1638SEA specifically addresses the 30-watt segment of this lineup, providing a standardized solution for single-ended audio output stages within the manufacturer's high-fidelity product range.

Replacement Considerations

Cross-reference the primary impedance and power handling capabilities with existing designs. Verify that alternative transformers support the same 40% screen tap functionality if ultra-linear operation is critical to the circuit performance.