Ultimate Guide To Guitar Pedal Buffers
Love them or hate them, if you’re building a large pedalboard, a buffer can make or break the sound of your guitar through your amplifier.
If you’ve never used a buffer or even if you don’t know what a buffer is, we’ll cover everything from understanding how to use one through to understanding which type of buffer to use on your pedalboard and where to place it to get the most benefit from it.
What Is A Buffer Pedal?
A buffer pedal is an active (powered) circuit that will preserve the frequencies from your guitar, mainly the higher frequencies, and maintain the strength of the signal as it progresses through your signal chain.
Think of a single buffer as a 1:1 amplifier that changes the impedance (sensitivity) of your signal, rather than the level or volume. An ideal buffer will take your guitar’s input with an impedance of around 1M Ohm and output it at something much lower, like 80 – 150 Ohms. This will essentially make it less susceptible to issues and react more as if we’re plugged directly into the front of your amplifier.
A buffer shouldn’t colour or change your tone, it simply reintroduces the original signal strength from your guitar through your entire pedal chain. However, if your buffer doesn’t match that input impedance of 1M Ohm and output impedance of 80 -150 Ohms, you may notice some colouration of your tone. Lower impedances would make your tone a little muddier and high impedance would make your tone a little brighter.
This will most likely be the least exciting pedal on your board, however, it can be the unsung hero that rescues your sound from ‘tone sucking’ pedals.
Why Do I Need A Buffer Pedal?
Every foot of cable you have between your guitar and amplifier will impact your signal as it is adding capacitance. This doesn’t just include the long cables between your amp & pedalboard and pedalboard & guitar. We’re also talking about all of the patch cables between all of your effects pedals as well.
Your standard guitar cable will produce about 30pF of capacitance for foot (100pF per meter) which may not seem like a lot. However, if you add up all of the lengths of those cables, you’d be surprised at how much cable you actually have between your guitar and amplifier.
A great example of how capacitance affects your signal can be found by simply using the tone control on your guitar. This tone control uses a capacitor to send some of the higher frequencies from your guitar, to ground. This process of sending a frequency to ground essentially removes it from your overall guitar tone. The more you roll down this potentiometer, the more high end you lose from your signal.
With this in mind, the more cable we have, the higher the capacitance and the more high-end clarity we lose from our guitar signal.
The job of a buffer is to boost this signal so that we regain the higher frequencies that would otherwise be lost.
But not everyone needs a buffer pedal in their signal chain.
How To Figure Out If You Need A Buffer?
There are 4 main causes of signal loss that could be improved by using a buffer:
- Long signal chain with many True Bypass pedals
- Long guitar cables (15+ feet)
- Low input impedance pedals
- Tone sucking pedals
If you don’t use many, or any pedals, in your rig, the odds are you won’t need a buffer. However, if you’re on my site reading how to build guitar effects pedals at home, it’s highly likely that you have a fair few pedals on your pedalboard.
If you do use a few effects pedals or use long guitar cables, we need to figure out if a buffer will actually impact your tone or not.
A fantastic test for this is to first play through your full guitar rig as normal. Really try to pay attention to the high frequencies. Next, plug your guitar directly into your amp with the shortest possible length of guitar cable and play the same licks.
If you notice that your guitar tone is brighter and clearer when plugged directly into your guitar amplifier, this is a good indicator that you could potentially benefit from a buffer in your signal chain.
Do You Already Have A Buffer On Your Pedalboard?
If your pedalboard is made solely of DIY guitar effects pedals that you’ve built, you should know whether or not they contain a buffer. However, when you pick up a prebuilt pedal off the shelf of your local guitar store, it’s tough to know whether or not it contains a buffer.
Firstly, if you have a Boss or Ibanez pedal on your pedalboard, you can be fairly certain that you already have a buffer in your chain. All Boss pedals, from their tuner through to their Metal Zone, utilise a high-quality JFET buffer.
How good are these Boss buffers? Robert Keeley from Keeley Electronics and Josh Scott from JHS pedals love them and that’s enough validation for me! Here’s a link to Josh’s video on buffers where he talks about Boss’ buffers:
How To Use A Buffer Pedal?
Using a buffer pedal really comes down to the type of buffer that you’re using.
Most buffers have a simple input jack, output jack and power socket. There are no controls and it’s just a simple plugin and play type pedal.
However, other buffers may have additional features. Some buffers offer stereo outputs with phase options and others have built-in boost controls or tone shaping controls to really sculpt your signal. If you have lots of buffers on your board, you may need a bit of a volume boost, but we’ll come onto that later.
If you’re new to buffers, I’d strongly recommend starting with a simple plugin and play unit and once you know more about your requirements, you can start getting more complex and introduce additional features.
Where To Place A Buffer In The Signal Chain?
When it comes to where you should place a buffer in your signal chain, there really is no right place and it comes down to personal preference.
Beginning of a chain
If you place a buffer at the beginning of your signal chain, you will be able to nullify the long cable capacitance effects on your guitar signal.
Middle of a chain
A buffer in the middle of your signal chain is a fantastic way to help push your signal through a larger pedalboard. With anything more 8 true bypass pedals, this is definitely something to test out.
End of a chain
A buffer at the very end of your signal chain will clean up your signal, restoring the high-end frequencies before hitting the front end of your amp.
You may find, depending on the size of your rig, that you need a few buffers to really get your signal back to where it should be. As they’re such simple pedals to build, you can create a few of them and add them into your chain wherever needed.
What Types Of Buffers Pedals Are Available?
When it comes to buffers, there are generally two different types available. These are transistor buffers and Op-Amp buffers. Here’s a little more information about these two different types of buffers:
Transistor buffers generally require less power to operate than operational amplifiers (Op-Amps) and are more than adequate for 90% of your buffering needs. They’re also much smaller in physical footprint than Op Amps so it can be a little easier to fit a transistor buffer in your pedal enclosure.
Whilst an Op-Amp buffer may require fewer components to create, I generally find them a little easier to build. With 2 capacitors, 2 resistors and a single transistor, we can have a buffer up and running in no time.
Op Amp buffers
Op Amp buffers, as stand-alone pedals, are sometimes a little overkill. However, if you’re building a drive pedal, an Op-Amp is a good choice as it provides you with a spare gain stage to use within your circuit whereas a transistor buffer will have nothing extra to use.
The main drawback of an Op-Amp buffer is that some believe it to be a little too hi-fi sounding for their taste when compared to a more natural transistor equivalent.
As with everything, there is no correct type of buffer to use on your pedalboard. It really comes down to personal preference and taste. Thankfully, both transistor and Op-Amp buffers are incredibly easy builds with very few components so why not build both and see which you prefer.
When Not To Use A Buffer?
By now, you’re probably thinking that a buffer is going to be the saviour of your guitar tone but before you start putting your shopping cart together to buy all of the necessary components, there are times when a buffer isn’t needed. Let’s take a look at these so you know both sides of the story.
If your guitar uses active pickups (EMG, Fishman etc) or if it has a built-in preamp, you will find that a buffer at the beginning of your signal chain, simply isn’t necessary. Guitars with active pickups and built-in pre-amps have a much lower output impedance so those precious high-end frequencies are already maintained by the onboard electronics. The best way to tell whether your guitar has active pickups or not is to see if your guitar takes a battery. If there is a slot of a 9-volt battery, odds are there are some active electronics in there that will mean you do not need a buffer at the start of your signal path.
There is such a thing as ‘too many buffers’ in your chain. If you have too many buffers on your pedal you will lose some of your level (volume). Brian Wampler did a video here on what a pedalboard with 17 buffered bypass pedals sounds like:
In here, he shouts out Jack Orman, one of the original DIY pedal builders and the experiment he did into this very thing. Jack found that for every buffer, you lost around 0.6dB of volume. This may not seem like much, but if you start adding this up across your pedalboard, you can start to see why it may become a problem. This loss of volume is why you may sometimes find buffers combined with boosters to help combat this loss in volume.
When it comes to buffers, there are some pedals that really do not play well with them. Any pedals with a low input impedance would ideally be in the signal chain before your buffer. A prime example of this would be fuzz pedals. If the input impedance of your fuzz pedal is above 500K Ohms, then you should be fine. Otherwise, place your buffer after the fuzz. The main reason we don’t want a buffer in front of these pedals is that it won’t allow them to clean up when you roll down the volume pot on your guitar. These pedals need to see the raw guitar signal whenever possible to achieve those magic and sought after tones.
There we have it. As you can see, buffers can be the unsung hero of a large pedalboard but knowing where to place them and what type to use really comes down to personal preference. There’s very rarely a right and wrong way to use a buffer. If that’s the sound that you’re after then who are we to say any different. Whilst a buffer won’t be the most exciting pedal on your board, it can definitely help you (in some cases) achieve the natural tones that you’re after.
As always, if you have any questions on anything in here, please do let me know.