
OPERATING INSTRUCTIONS
LEHLE P-SPLIT STEREO
LEHLE P-SPLIT STEREO#
Dear Musician!
Thank you for purchasing your LEHLE P-SPLIT STEREO!
I have been building units that switch, split and route signals with no technical compromises and with maximum musical fidelity since 1999. Your new LEHLE PARALLEL SW II comprises only the very best components.Every assembly of your LEHLE PARALLEL SW II has been made and tested in Germany.
Your LEHLE P-SPLIT STEREO is of extremely robust design and construction, to make sure that you get absolutely years and years of enjoyment from it. If you should nonetheless have a problem, or simply a question, just mail me or a member of the Lehle team at: support@lehle.com

I wish you the very greatest pleasure and success using your LEHLE P-SPLIT STEREO

Signal Routing#
Preconditions for passive splitting#
The LEHLE P-SPLIT STEREO is a passive splitter which can be used to split high-impedance signals to high-impedance inputs. There are certain preconditions which must be met to ensure that this is accomplished without problems and no loss of sound.
HIGH-IMPEDANCE SIGNAL SOURCES AND INPUTS
Passive magnetic pickups as generally used – in the form of single-coil and humbucker pickups, on electric guitars and basses – supply high-impedance signals. High-impedance signals have an output impedance in a range of 10 kΩ (10,000 Ω); the higher this figure, the more sensitive the signal is to interference.
High-impedance inputs are found on guitar and bass amplifiers, and on sound cards with a “Hi-Z” input; “Z” stands for the impedance, which is the physical expression for the internal resistance of a signal source or a signal input, and thus defines its low/high-impedance performance. High-impedance signals are generally transmitted unbalanced and are relatively susceptible to interference. Long cable routings audibly attenuate high frequencies. Electromagnetic interference from the environment then becomes more noticeable than in the case of low-impedance and balanced signals.
There are, nonetheless, very many musicians who swear by the sound of an electric guitar or bass with passive pickups connected directly to a tube amplifier via a good cable.
The input impedance of high-impedance inputs is generally 1 MΩ (1,000,000 Ω) or more. Here, too, the input becomes more sensitive, the higher this figure is.
LOW-IMPEDANCE SIGNAL SOURCES AND INPUTS
Keyboards, active pickups, preamp outputs, sound cards and mixers supply low-impedance signals. The output impedance of such signals is typically 100 Ω to around 600 Ω.
Low-impedance inputs predominate in the line input of mixing desks, power amps and sound cards with no Hi-Z inputs, and also in microphone inputs and in virtually all balanced inputs. Low-impedance inputs have input impedances of around 600 Ω to 10 kΩ.
WHAT IS POSSIBLE
The LEHLE P-SPLIT STEREO can be used to split the signal from an electric guitar or electric bass with passive magnetic pickups to two amplifiers, each of which has high-impedance inputs. Please use the shortest, best-quality possible cables for this purpose. You will hear the 100% original signal on both amps.
Instead of an amplifier, you can also split the signal to the Hi-Z input of a sound card. It’s important to remember: a high-impedance signal can be passively split if you connect only high-impedance inputs.
You can split a low-impedance signal, such as the output from a preamp, e.g. the LEHLE SUNDAY DRIVER II or the output from a sound card, to a tube amp with a high-impedance input and the lowimpedance input of a power amp. Since the signal to be split is a low-impedance one, you can connect low-impedance and high-impedance inputs behind this if you wish there won’t be any problems!
WHAT IS NOT POSSIBLE
Audible sound losses will occur if you use long cable routings from the passive guitar to the splitter and from the splitter to the amps. The sum of all cable lengths to the splitter and to the amps should generally not be more than 10m. Your individual taste will ultimately decide, however.
Splitting your high-impedance instrument signal to a low-impedance input, such as the line input of a mixing desk, for example, and to a high-impedance input on a tube amplifier using the LEHLE P-SPLIT STEREO will result in the high-impedance input being attenuated by the low-impedance input of the mixing desk. The signal will become significantly quieter and will lose presence
Solution: these problems can be effectively eliminated by connecting a preamp or a buffer, which will convert the highimpedance to a low-impedance signal, in the signal path. The LEHLE SUNDAY DRIVER II, for example, is suitable for this position.
INPUT | DIR | ISO | |
Hi-Z | Hi-Z | Hi-Z | |
Hi-Z | Low-Z | Hi-Z | |
Hi-Z | Hi-Z | Low-Z | |
Hi-Z | Low-Z | Low-Z |
INPUT | DIR | ISO | |
Low-Z | Hi-Z | Hi-Z | |
Low-Z | Low-Z | Hi-Z | |
Low-Z | Hi-Z | Low-Z | |
Low-Z | Low-Z | Low-Z |
General Description#
1. INPUT SOCKET
Connect the output of a stereo effects unit, keyboard or DAW here.
The input signal is fed into this socket. The LEHLE P-SPLIT STEREO operates entirely passively.
The input signal remains connected to the ISO and DIR outputs at all times, with no semiconductors or any other active components in the signal path.
Both balanced and unbalanced signals can be split, since the LEHLE TRANSFORMER HZ is capable of handling both types.
If the INPUT SOCKET L is not occupied, the signal of the INPUT SOCKET R will automatically be mirrored. This way you can split up to three galvanically isolated outputs.
2. OUTPUT SOCKET
Connect the input of an amplifier, mixer or effects unit to be connected directly to the LEHLE P-SPLIT STEREO input here.
The input signal and its ground are present directly on the DIR socket. The signal from the DIR output is always the same which is fed into the input (1). If the input signal is unbalanced you will have an unbalanced direct signal at this socket. The same will occur with balanced signals.
3. PHASE INVERTER SWITCH
The phase of the input signal from the ISO output can be inverted if necessary.
This switch can be used to invert the phase of the input signal from the ISO output socket by 180°.
Splitting signals to two amps may sometimes cause phase cancellations, resulting, for most musicians, in a “thin” sound. Inverting the phase eliminates this problem.
Experiment to find out which position you prefer – as always, your individual taste is what counts!
4. GROUND LIFT SWITCH
Connect the grounds of the DIR and ISO output if necessary.
Pressing this switch connects the ground conductors of the ISO and DIR outputs. Connecting the ground conductors of the DIR and ISO outputs can help in some situations, depending on the units connected and on their power supplies.
Use the ground lift switch to find out for yourself the position in which noise is minimised.
5. ISO-OUTPUT
Connect your amp or the audio input of a DAW or a mixer here.
The ISO output has an input signal which is isolated by means of the LEHLE TRANSFORMER HZ.
A balanced or an unbalanced signal is possible, irrespective of the type of signal fed from the input.
„Toggle the phase and ground switches, until you have less noise and the best sound.“
Joe B., Guitar player
6. BASE AND FIXING
If required, mount the P-SPLIT STEREO to a pedalboard using the mounting kit.
The P-SPLIT STEREO can be mounted to a plate such as a pedalboard using the two holes in the bottom of the pedal. You can find the optional LEHLE Mounting Kit V3 (order number 100981) online at www.lehle-components.com.
To mount, undo the four housing screws by using a 2.5 mm Allen Key and detach the cover.
Then fix the device base to a base plate using the two screws, the washers and the spacers of the Mounting Kit. Attach the cover and tighten the four housing screws – done! For flexible solutions we recommend using 3M Dual Lock™ instead of Velcro for stability, which you can also find in handy sizes at www.lehle-components.com.
If you are using the Velcro / Dual Lock™ method, please make a note of the serial number on the bottom of the pedal before you cover it, in case you have a support question for us later and don‘t fancy dismantling your board!