How do you connect a Lundahl line transformer correctly?

Connection is carried out according to the data sheet: windings can be connected in series or in parallel for different step-up or step-down ratios. Important factors are the correct phase position, grounding and the desired operating mode, either balanced or unbalanced. Incorrect wiring can lead to level loss, hum or incorrect channel phase. If you are unsure, the Lundahl data sheet will help; it can be found in the BTB online shop under Downloads for the respective product.

Example:

Line transformer LL1680 as a single-ended output transformer for the ECC82 – idle current is max. 5 mA, Ra = 15 kΩ, Rl = 600 Ω.

For an unbalanced output (RCA), diagram B applies; for balanced operation (XLR), diagram A applies accordingly.