Signal Path



  1. Signal Path Ground Isolators
  2. Signal Path Music
  3. Signal Path Music
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Hundreds of pedals and rack mount effects are available in today’s booming music market. The chain of sound effects is a part of the performers signature sound. We can easily identify a specific player just by hearing a few notes of their signature tone. Think about how fast we can identify the guitar tones of Steve Lukither, Eric Clapton, Jeff Beck, Joe Walsh, Joe Satriani and Eric Johnson. Paired with their individual playing styles and amplification, they all use effects to create their signature guitar tones.

In the seventies and eighties I was the pedal board king. I used a minimum of 10 pedals at any given time. I learned the hard way about keeping the integrity of my guitars signal path through all those effects. Countless, repetitive articles have been written on the following question.

What is the best order to place sound effects in a signal path?

There is a standard placement of traditional effects that can allow a signal to weave smoothly. From the guitar to the amp, effects send to the effects return or a mix of both. Their placement can either add or detract from the performance and sound of a signal. Below I will offer suggestions for sound effects placement of the three above scenarios.

  1. The amplified signal is known as line level. Mic Preamp-Hardware Effects. The mic preamp sends the line level signal to any number of analog signal processors including EQ and compression. This step in the process is optional, and in less expensive studios, is often skipped in favor of digital signal processing within the DAW.
  2. In a mobile communications system, the radio signal path through the air is subject to multiple reflections, and the signal from the transmitter to the receiver can travel different distances and thus the same signal can reach the receiver with different strengths and delays in time.

The signal passes through these blocks from top to bottom: Audio from WaveLab Cast. Reordering the effect slots affects the signal path. The Master Section meters monitor the signal between the Master Level pane and the audio hardware or file on disk. Audio hardware or file on disk.

Effects Pedal Placement between Guitar and Amp

Clean channel only!

Before experimenting with the suggested pedal placement, adjust the channel controls of your amp to your usual positions. The clean channel should be pure not overdriven.

Signal Path:

Guitar > distortion/overdrive pedal > amp

To achieve the best performance from any overdrive pedal the output of a guitar signal must hit this effect first. All overdrive pedals perform best when the guitars volume is turned all the way up. This sends the maximum output voltage from your guitar pickups to the input of the overdrive pedal. If you need to vary the output volume of an overdrive pedal, incorporate a volume pedal after the effect. This will keep the tonal integrity of the overdrive’s output.

Tip: Single and double octave harmonics are more sensitive when using the rear/bridge pickup with an overdrive pedal. The guitar’s volume control must be turned all the way up to achieve this.

Signal Path:

Guitar > distortion/overdrive > phase shifter > chorus > flanger > wha > delays > reverb > volume pedal > amp

Try this order first before experimenting on your own. I always recommend the delay/reverb placement just before the amp or volume pedal. Think of reverb as a coating over the entire signal adding the final texture. Many combination floor pedal processors have a predetermined signal path order of effects. If the multi effect floor processor allows you to choose the order. Try the above pedal arraignment first.

1st Tip: The wha-wha placement can vary. Try placing it after the distortion pedal. Experiment, chorus or flange the wha effect.

Path

2nd Tip: T-wah’s, Octave dividers, Ring Modulators and Synth Pedals all require maximum pickup out put from the instrument. Treat their input signal the same as you would an overdrive pedal.

Compressors: I have left compressors out of the chain because their placement in the signal path can vary. For example, if you want to compress the over all signal path. Place the pedal before the delays and reverbs. Using the compressor as an effect works well right before or after the overdrive.

Multiple channel amplifiers and foot pedals: Set up your amp as you normally would prior to plugging in any effects.

Signal Path

Signal Path:

Guitar > distortion/overdrive > phase shifter > chorus > flanger > wha > delays > reverb > volume pedal > amp

Follow the above order as a starting point when using multi channel amplifiers. Ease into using distortion pedals with over drive channels. However, if used carefully an over drive pedal can be used as a boost effect in any hi gain channel. Please note: Using time effects such as chorus, flanger, delay and reverb before an over drive channel creates a different effect than if used in an effects loop or a clean channel. You are actually over driving the time effects rather than using them to create textures after the hi-gain signal.

Effects loops

Signal path:

Guitar > Amplifier > processor or processors in an effects loop

Signal Path

Using rack multi effects signal processors in an effects loop has many advantages in creating sound textures. The only draw back is that your overdrive sounds from the processor are more compressed because a pre amp is driving them as opposed to a direct guitar signal. Combining a signal processor with multi channel amplifiers however is usually the best of both worlds. You can easily add your time effects as textures to all of your channels in any order. Even the overdrive patches from the processor can be used as a boost effect. The most important adjustment in the hook up is to get your input and output levels balanced on both sides of the loop. Read your manuals!

When combining multiple effects processors together star out by using the same pedal order listed above. Example: If you are using a rack compressor and a time processor (flange, chorus, delay and reverb) place it before the time processor to compress the original signal (recommended). Then try it after the time rack to harness harsh peaks.

If your amp has a mix control on its effects loop control panel. Turn it to the wet setting and use individual mix settings provided by the processor. The only time I would use an effects loop mix control, if provided would be if I were using an old fashion tape delay. The effects loop mix will contain a higher fidelity dry mix than the analog taped delay dry mix signal.

Effects loops and foot pedals

Signal Path Ground Isolators

Signal Path:

Guitar

Guitar > Foot Pedals > Amplifier > processor or processors in an effects loop

If you really want to create original vintage guitar sounds this is the way to go. Use your favorite over drive, wha, T-wha, phase shifter, flanger, and volume pedal etc., on the front end of the amp. Even a compressor in pedal form is cool for great slide effects and country riffs. Use your time processor in the effects loop for overall texturing. If the signal path of this style of rig is run correctly, you can create any sound out there.

Signal Path Music

In this episode Shahriar takes a look at a non-functional R&S FSEK 40GHz spectrum analyzer. The instrument’s LCD screen back light no longer works and the front glass is broken. Furthermore, no testing can be done until these problems are resolved. The CCFL tube is replaced with an LED counterpart and a new front panel glass is also installed.

Signal Path Music

After power on it becomes clear that the instrument has other defects. The internal PLL is unlocked. It is observed that the OCXO module is cold and potentially not working. Examination of the LO board shows a bad inductor on the DC filter side. After this problem the instrument operates correctly but only for signals below 7GHz. After further testing it is discovered that the YIG tuned filter on the pre-selector path is not tuning at all. Eventually the fault is traced to some operational amplifiers on the YIG driver board. The repaired instrument is verified for correct operation.