LL1527 Lundahl trasformatore d'isolamento

LL1527 is a truly general purpose transformer for microphone or line input, for output, for splitting 1 direct + 1 isolated and for galvanic isolation of units. LL1527 has been generally accepted by the audio industry as the general purpose audio transformer. The LL1527 is built-up from two coils, each with one primary and one secondary winding separated by an electrostatic shield. The core is a high permeability mu metal core. The transformer is housed in a mu-metal can. In the LL1527XL, the core is about 45% larger than in the LL1527, resulting in a higher signal level capability

LL1527, one of our oldest audio transformer designs, is still in production and still very popular. Many sound engineers have a couple of LL1527 laying around to be used when problem arises. Frequently engineers tell us: “I had some hum in my system, but as soon as I installed one of your magic LL1527, the system was dead quiet…”
Due to an excellent bandwidth, a reasonably low copper resistance and a high signal level capability, the LL1527 can be used both in input and output applications with no sound degradation. The LL1527 will break up ground loops, convert balanced to unbalanced and unbalanced to balanced systems.

                                                            Balanced-to-unbalanced conversion

                                                    Unbalanced-to-balanced conversion

It is also suitable for splitting 1 direct + 1 isolated:

Splitting 1 direct + 1 isolated

LL1527 is not suitable for splitting 1 direct + 2 isolated, as it in this configuration may pick up magnetic noise from mains transformers and electrical motors. For this application we normally suggest the LL1581XL.