Articles Effects Home Studio

Parallel Effects Part 2

After the recent release of the new Boss Guitar processor, I noticed a flurry of adverts selling off the older (but still good) Boss and other similar processors. Now for some, the reason for doing this is to help finance the upgrade – we’ve all been there! However, for those who can afford to keep their older FX processor, there is a very attractive option available – using the older unit in parallel with the new to do some very nifty things indeed. While this article is written specifically with guitar in mind, this is not only something guitarists can use!

Parallel Effects revisited
You will remember a while back I wrote an article on parallel effects – If not, you can find it here. To sum up: When running effects in parallel, we drive the inputs of two or more effects with the same source signal by splitting it into two or more ‘branches’ or ‘chains’. Then the outputs of the two branches can be combined using a mixer. This gives a range of sound combinations not available with series processing – allowing more than one different sound  (like a clean sound and a distorted sound) to be mixed together.

With two multi effects processors, you have the freedom to take things further than you can with a few pedals – each branch can have it’s own overdrive and distortions, and even dedicated reverbs – which are often to processor intensive to be able to have more than one in an effects unit. The icing on the cake is that, with most FX processors made in the last 10 years or so, there will be amplifier, speaker and even microphone modelling. The upshot of this all is that you can give each branch it’s own, distinct sound – in effect, making it sound like two different amplifiers and even (with the right tricks) making it sound like a double-tracked guitar part. All live and real-time.

The return of Splitting the Signal
The methods I previously mentioned for splitting the signal into two chains were: splitting buffers (sometimes called ‘Spluffers’), DI boxes, stereo mixers and stereo effects. All these will still work, but with many multiFX processors you have even easier and more flexible methods, namely:

Buffer Outputs – Many units have a “buffer” output, specifically for driving other processors or amps. These outputs give you an identical copy of what you are putting into your input, and are obviously perfect for this application.

Tuner Outputs – Some units have tuner outputs, which are basically glorified buffer outputs.

Effects Loops

Conventional method of using an effects unit in series in the loop of another
Connecting the second unit so it is connected in parallel

Finally, we have the humble effects loop, which is designed to allow you to insert one unit in the internal signal path of another. Normally this is done with a send jack and a return jack (often two returns, to allow for the return signal to be stereo). However, wiring it up this way places the second unit in (plain old boring) series somewhere in the signal path of the first. To use the second in parallel, you don’t use the return jacks on the first unit – you plug the outputs of both units into a mixer and the mixed signal to the amplifier. Of course, you could use two amplifiers, one for each, but it is usually more practical to have one.

Where the effects loop is really powerful is that the settings for the loop (on/off) can be written into a patch on the master unit (usually your newer one) so you can have your second unit set up to work on one patch and be switched out of the next – a very powerful feature. You will often be able to bypass the effects loop via a pedal on the master unit too, allowing the second unit to be bypassed with a floor pedal switch without changing patches.

Many better effects units will allow you to specify where the loop is placed in the internal chain of effects, allowing you to use it before amplifier and speaker emulation (for instance) in one patch and after it in another.

The Bride of MIDI
If your master effects unit is capable of sending out a MIDI program change message, it is easy to plug a cable from the MIDI Out on the master to the MIDI In on the second so that changing a patch via the pedal on one changes the patch on the second at the same time. Take some time to read the manuals and find out if a nifty feature called patch mapping is supported as this lets you have the second change to a different patch number from the first.

The Return of the Son of Tips and Tricks

  • Try a short (1-12ms) delay on the second unit. Use only the wet signal, no direct – this can really make the two stand out from each other.
  • Building on the last point, longer delays can be made to sound really different from the original  by using different amp and speaker sims.
  • If you are working in studio (or anywhere where you can experiment with stereo), take the time to position things carefully to get the best separation between the sounds. I often like to have a dry sound panned on or near centre with the second panning around the extremes.
  • Keeping one sound relatively dry and tight with fewer and more subtle effects will make sure that you can mix things to make it stand out, regardless of how many effects are used for the second sound.
  • Using similar reverbs on both sounds will make them mask and blend together better – sounding like they are both being played in the same space. Using different types of reverb can make them stand out from each other.
  • Experiment and keep an open mind, some of the best sounds are found by “happy accident”
Articles Effects Home Studio

Parallel Effects Part 1

Whether in the studio or on stage, as recordists or musicians we all run into a situation eventually where one sound doesn’t do the job. It might be a distorted electric guitar sound which doesn’t have the clarity needed. On the other hand, the clean electric guitar sound might not have the punch you want. Wouldn’t it be nice to have a combination of both?

So you take two amps, set one to distort and the other to a clean sound, then mic up and mix the two. Problem solved! This is the simplest example of using two effects in parallel (remember, an electric guitar amp is an important part of the electric guitar sound and, as such, is an effect). The analogue for a bassist is when, in the studio, the engineer uses a DI box to get a direct sound while also driving a bass amp and miking it up.

Series Effects
This is the usual manner of connecting effects – from the output of one into the input of the next, into the next, etc.. This is called series connection. Series connection is a perfectly valid way of doing things, and has been used to create some of the effects sounds we all know and love. However, if you only use series connection of your effects, you are limiting yourself. There is a whole other world available to you in parallel effects.

Parallel Effects
When running effects in parallel, we drive the inputs of two or more effects with the same source signal (such as the electric guitar or bass in the example) by splitting it into two or more ‘branches’. Then the outputs of the two can be recombined using a mixer. This gives a range of sound combinations not available with series.

Of course, it need not stop there. Now it is possible to treat each branch as an effect chain. Each can also be EQ’ed differently at the mixer and panned to different positions in the stereo soundstage for a really large, spacious sound.

For recording, you can record each on two separate tracks on a recorder. This allows you to decide how to mix things later in the mixing process, when you have a better idea of what will work best in the song. For a guitar signal, another option is not to mix them back together, but to drive two different amplifiers.

Splitting the Signal
In a perfect world, you would be able to use a simple splitter cable to split the signal into two branches. Unfortunately, the inputs of many effects do not play nicely with others, and one may ‘snatch’ all the signal for itself, leaving nothing for the other effect. There are a few ways of getting around this.

  • Splitting buffers or ‘Spluffers’ – these are specially designed for parallel effects usage. They consist of two identical buffer preamplifiers in one box which have separate outputs but share the same input. Unfortunately they are not very common and must usually be built to order.
  • DI boxes – using two identical DI boxes and a splitter cable is essentially the same as a spluffer, but is more easily available.
  • Stereo Mixers – using a stereo mixer is another option. Pan your input to the centre and the left and right outputs are identical buffered signals. You could also use spare auxiliary channels or output busses on your main mixer if you have them to spare.
  • Stereo effects – many effects such as delay, chorus and autopanners are by their nature stereo and have separate outputs for each channel. A delay can be set to a short delay of a few milliseconds (be aware that this can change the tone quite radically, so experiment with finding the right delay time which works for you), and similarly, chorus can be set to be relatively subtle.

A Few Ideas
Here are two of my favourite parallel effect tricks:

Instruments with two separate outputs – If you have an electric guitar with a piezo bridge, you can use this to drive a second effects chain. A similar thing is to have a two pickup electric guitar or bass modified, so that each pickup feeds it’s own output jack. Even if you don’t process the two branches separately, combining the two with a mixer gives you a different sound than doing so with the passive switch in the instrument This works especially well when you have an instrument where each pickup sounds great by itself, but has a nondescript sound with both together.

Dynamic delay – I will often compress one branch and use a delay on the second. When I play softly, the compressed branch stands out as the compressor is boosting the level. As I play harder, the louder the delayed branch becomes, while the compressed one stays at a constant level. This means that the delay only becomes audible as I accent beats. This trick works with almost any effect on your second branch.   If you use a stereo delay and pan it hard left and right while the compressed branch is panned to the centre, the delays bounce around the extremes, with the compressed sound rock solid in the centre.

Comb filtered branches – Use a graphic equaliser on each branch. On the first EQ, cut every second frequency band by about 6dB or more and boost the other bands by the same amount. Now reverse these settings on the EQ on the second branch. This gives you two totally different tonalities, which fit together perfectly in a mix. For a guitar sound, try adding overdrive to each branch (either before or after the EQ – it will sound quite different depending on the order).