Introduction

All lundahl transformers have physically a symmetrical construction per definition. Interesting wise this has totally different advantages for each product. For the small signal transformers, a natural application is using them for symmetrical signals, and conversion of symmetrical to non-symmetrical (and vice versa).

Symmetrical (XLR) connections are the best and professional way to eliminate hum problems permanently. The ground loop is high impedance with XLR, and with transformers the ground loop is not even present. Furthermore, the cables are symmetrical so they do not radiate signal and do not receive unwanted signal. Mains hum can be radiated into a symmetrical (XLR) cable, and also cross talk is like zero.

So you find this where large lengths are used, such as on a music stage. Other applications are for Studios with hundreds of connections to one panel, where cross talk and hum can not be tolerated.

Also you find the XLS connections where HiFi users choose XLR connected equipment to permanently solve hum problems.

There are several ways to use an interconnect solution from Lundahl transformers

1) Build in a signal transformer in your equipment, either at the source or at the receiving end, or at both ends.

This is very easy to do and generally you will choose the 1:1 option. Please check here for some more information about this. How to choose Symmetrical to unsymmetrical transformers. However when constructing new equipment you can also consider a 1:2 1:3 or 1:4 step up. There is a lot of advantage in this, since distortion and noise of a good signal transformer is much lower than an active stage.

2) Use a Lundahl interconnect solution with transformer inside.

This solution can connect XLR equipment to RCA equipment, the only correct way, and that is with a transformer. The actual interconnect cable is an RCA cable, or the XLR cable depending on the connector you choose. Also with the RCA cable, inside it works like an XLR too. This is the only professional way to connect XLR to RCA.

There are several types:

• RCA to RCA. This the LL6810-PHMPHM. The best interconnect cable ever build. Period. This is made from a very high quality connectored ORIGINAL MOGAMI STUDIO CABLE FROM JAPAN, which is cut in two ends in the Lundahl workshop in Sweden. In the middle is mounted a 1:1 high impedance high bandwith transformer, which makes this a universal connector cable for Audio signals like coming from a CD player or pre-amplifier. Before you spend 800$ on a "magic snake" cable or other voodoo, better stay down to earth, and try a REAL solution like LL6810-PHMPHM. To help you decide, all tone studios use Lundahl cables in quantities of 40pcs or more per panel, and solve their hum problems with it.
• XLR to RCA, XLR to Jack Plug, or XLR to XLR male, female. LL1584 and 156Xseries.
  These can all be used in both directions.
  

Low impedance LL1584.

LL1584 is available in four versions:
LL1584-3FXNP2C. Female XLR connector to 2-pole ‘A’-gauge 1/4" jack plug
LL1584-PHF3MX. Female Phono (RCA) connector to male XLR connector
LL1584-3FXPHM. Female XLR connector to Phono (RCA) male
LL1584-3FX3MX. Female XLR connector to male XLR connector

LL1584 DATASHEET HERE / ALL VERSIONS

 

High impedance LL156X.

The LL156X is available in four versions:
LL156X-3FXNP2C Female XLR connector to 2-pole ‘A’-gauge 1/4” jack plug
LL156X-PHF3MX Female Phono (RCA) connector to male XLR connector
LL156X-3FXPHM Female XLR connector to Phono (RCA) male
LL156X-3FX3MX Female XLR connector to male XLR connector

LL156X DATASHEET HERE / ALL VERSIONS

 

 

High impedance LL2615. All with MALE Phono (RCA)

LL2615-3FXPHM Female XLR connector to Phono (RCA) male for 10k unbalanced load
LL2616-3MXPHM Phono (RCA) male to male XLR connector for 10k balanced load

LL2615 DATASHEET HERE

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