Friday, January 18, 2013

Gear Review: Lehle P-Split II

The time has come to publish my very first gear review in this blog! And the first piece of gear i'd like to review is the Lehle P-Split II.

Since this is the first gear review i write in this blog i'd like to explain my philosophy about the products i describe.
My goal is to provide some in depth information about any particular product with sound/use examples. When i think of any "audio" product, be it software or hardware i ask myself following questions: What is this product for? (obviously), Why do i choose this certain product and not the other item with same functions? what makes this product special? In case of software: is it worth to buy it, if there are free products of same kind, or plugins that are included in the most DAWs? Is the product worth the money? Does the product actually handles it's job? Would i buy this product?
It is of great importance to prove my words with actually testing the product and publishing the results, so people can hear what the product does and not just rely on my opinion.


Ladies & Gentlemen, please welcome the:

 Lehle P-Split II

The p-split is a passive splitter that allows you to split a guitar signal in two. The most common cases of it's use are: routing your guitar signal to two amps or to one amp and a recording system. You may use it for re-amping as well, as it will isolate the output of your recording system from the amp and therefore avoid ground loop. This item features an 1/4" TS input (for a guitar cable) a direct (DIR) and an isolated (ISO) output, as well as a phase reverse, and ground lift switches.

Good, this seems to be a pretty trivial task and one could ask whether the price (119,00 € in Europe 169,00 € in US) is justified, because one actually can buy a Behringer AB100 for 19,00 €/25 $ that does the same job? I do not want to discuss the physics behind this gear, i am interested in the tonal quality. Cheap AB boxes/splitters add a lot of background noise and are unsuitable for recording or an advanced concert, while the P-Split is the cheapest device that shouldn't deform the sound and add any noise.

It should be clear, that you can not expect 1 to 1 signal fidelity when splitting your guitar sound, especially if this device is passive. The big question is however, how strong the difference will be if you use it for recording or a live situation.

That's what my test last night was all about.


My test setup was kept as simple as possible:

My japanese Jackson Kelly electric guitar with new Ernie Ball strings connected to the Lehle's input via a quality 3m/10ft guitar cable. From the Lehle both DIR and ISO outputs were connected via short identical patch cables to 2 identic HiZ-preamps set to same volume and recorded in to my DAW which is Cubase. Afterwards i made a reference recording, with the guitar plugged in straightly to the HiZ input of the preamp.

So I got 3 tracks: DIR track from the Lehle, ISO track from the Lehle and my direct track recorded straightly in to the preamp. It became obvious that the straight direct track was noticeably louder then the both lehle's tracks. The sonic differences of the 3 tracks were  rather neglectable. The noise floor of the lehle was very good. It didn't actually add any noise, while the ISO output seemed to sound
even clearer, obviously due to the galvanic isolation of the unit.

track 1: Original test with a clean electric guitar sound. Samples follow in 3-piece groups: 1 note the ISO signal, the second the DIR signal, 3rd - the reference signal.

track 2: Same track with Guitar Rig 5 high gain plugin on it. 

I then analyzed the wave-forms from the DAW and, as expected the DIR signal looks more similar to there reference, while the ISO signal tends to contain a bit less information. The transients (the first and the loudest peak of an audio signal) of the ISO output were significantly lower then those of the DIR and reference tracks.

pic.1: The visual appearance of the  3 waveform. The reference track has noticeably larger amplitude, the DIR track looks more like the reference but just like the ISO-track seems to have a bit different dynamic range. The ISO-track's transient and harmonics seem to have a little smaller amplitude. If however set to the equal levels the differences will become even less significant. No artifacts or extreme differences between tracks could not be seen or heard during the test and in the aftermath.


An accurate audition via both studio monitors and headphones did not reveal a huge tonal difference. The difference, as you will be able to hear is there. The signal gets changed a bit. However I couldn't state that the splitted signal lacked anything or sounded worse then the reference. It is just slightly different. If you count that your guitar signal will be processed while re-amping or a plugin emulation and most likely will be compressed to a certain degree the sonic divergence will become even smaller. I just threw a Guitar RIG 5 distortion preset over the combined track and you can judge the results for your self.

The ground lift  and the phase reverse switch can come in handy and it's definitely a wise complement to the P-Split II.

Short comment to the audio tracks: I placed the recorded signals close to each other, so one can instantly hear the sound changing , rather then listening to it after a longer pause or passage. ISO signal goes first, then the DIR track and then the reference.


All in all the lehle P-Split delivered a great job. Nor did it add any noise to the guitar signal, neither did it damage the original sound of it. Although the DIR and ISO outputs of the lehle were noticeably quieter then the reference track, following things are to conclude:

1. The reference track and the lehle test tracks are not the same but 2 separately recorded tracks, so a certain volume variation of the 2 takes should be taken into account.

2. The lower signal ouput of the lehle can be easily compensated within a DAW by trimming it's gain, or in a guitar amplifier by boosting the input volume/gain a bit. And you shouldn't be afraid of additional noise.

3. If you'd like the signal to remain as authentic as possible, I'd suggest you connect the ISO output to the amp you're playing and the DIR to your recording device. However I must repeat that the difference between the two is really neglectible.

Now, I'd like to answer the questions I have asked myself before the test:

Q. Who needs this product?
A. The lehle P-Split II comes in very handy in situations when you want to play through 2 different paths, be it an amp and a recording console, or two amps. It is also suitable  for re-amping. The only thing you'll have to adjust with re-amping is the output volume. The P-Split will cancel the ground loop and you will not get any 50 KHz noisebands.

Q. Why this and not a similar product? 
A. Although there are plenty AB-boxes out there that only cost a fraction of the P-Split the galvanic isolation makes this product stand out. It is the cheapest splitter of pro quality that i was able to find.

Q. Is the product worth the money?
A. Yes, it surely is. The item is built like a tank. It has only few functions: splitting and isolating, but it handles them at pro level. The most splitters of same quality will cost much more. B-sides nobody told you can't by it used.

Q. Would i buy it?
A. Well, I actually did buy it for the Sariola's single recording sessions and i'm keeping it.


Alright! The first gear review is done! It couldn't and shouldn't be rated as a scientific article, but in my opinion it is a pretty detailed review. If you however have any questions that you'd like to get answered regarding to the unit, feel free to leave comments and i'll gladly update the review! Thank's for reading!


  1. This was everything I wanted to know... Great review. Informative and to the point! Might want to look in to buffers? Lots of different opinions on the internet, your method seems rather objective!

  2. I had these mounted on the output of a Touring Pedal Board driving multiple amps. The Artist notice that the output was not as Hot as cable to amp, thus affecting the natural drive he wanted, and did not want to gain up the amps to compensate, thus, I had to remove the P-Splits, and add a All Access Buffer Box, in which did not reduce the natural output of the Board to amp.

  3. Wouldn't rasing volume on the last unit of the pedalboard solve the problem? I did not expirience significant gain loss when using the unit, But maybe if one uses less gain in the chain it becomes noticable. Thank you for your reply! Cheets

  4. I've been thinking of buying a high-quality splitter :
    your rigorous review has been very helpful to me.
    Thank you.

  5. Great job ! Already have 1 and its precisely as you described. Pro sound quality.

  6. The ISO and DIR tracks look exactly the same. Just mirror the ISO track and put it over the DIR track. Just an inverted phase ;)