As guitar players we are always searching for the ultimate tone!
One of the basic issues that everyone using a pedalboard is struggling with, is impedance mismatch.
A general rule of thumb: A high impedance signal is very sensitive to resistance or to what load it sees. A low impedance signal is not. Most guitars and basses typically have a high impedance output.
Whenever you want to do an A/B test it’s important to know your reference point.
In this case, the reference point is your guitar connected directly to your amp, using a 6m cable.
Most amplifiers have a 1Mohm (1 million ohm) input impedance.
The first thing we want to be sure of is that the guitar sees an input impedance of 1Mohm.
In the perfect world, all Stomp Boxes would have an input impedance of 1Mohm, but that is not the case.
If the first pedal in line has an input impedance of 100kohm (100.000 ohm) instead of 1Mohm, the guitar will sound different – typically you will lose high end frequencies/harmonics and volume. – All the fun stuff.
Equally important is the output impedance of the last pedal. Often it is way too high to drive a long cable back to the amp. The output impedance should not be more than 100ohm.
How can we solve this?
The solution is using a Buffer as the first and last unit. A Buffer is a small amplifier circuit that converts your high impedance input to a low impedance output. It has the same input impedance as an amplifier, which means the guitar will sound the way it should.The output is low impedance, which means it’s less sensitive to what load it sees or the length of the cable from your pedalboard to your amp.
Choose the right Buffer
There are different Buffers on the market and they don’t sound the same. Due to the Buffer being a small amplifier circuit, it will have a sound of its own. Make sure you choose a Buffer, that doesn’t color your sound noticeably.
At Caveman Audio we’ve developed a Dual Buffer called BUF1.
Beside the input Buffer we added a second Buffer to help you drive very long cables from your pedalboard back to the amp, without any tonal loss. Adding this pedal to your pedalboard will really improve your tone.
The ultimate solution
Is this the ultimate solution? – No, it’s not.We can improve your setup even more.
We have two solutions that offer what we believe is the ultimate solution. -The MR5 and the MR10 Loop Systems.
The MR5 supports five pedals, whereas the MR10 supports 10 pedals.
Using one of the MR Loop Systems will make you experience the real sound of your Stomp Boxes, without the impedance mismatch that you normally have in conventional loop systems.
The MR-system features impedance correction on every loop both on the input and the output side.
The result is that each Stomp Box sounds as if it was the only unit in your system, regardless of the combination you select.
The MR-series is without a doubt the most noiseless and silent switching loop system available.
Even in high gain and very high volume applications and of course, they support both Midi program- and control change commands.
Some would probably think “Is this really needed, when my pedals have True Bypass?”
I’m sorry to say that True Bypass is more a marketing gimmick than an asset to your sound.
It makes things a lot more complex as the impedance misalignments gets even more random depending on the combination of Stomp Boxes being on and off. So don’t be fooled by this True Bypass thing. – I’ll explain this issue in depth in another blog post.
I highly recommend you to have a look at your pedalboard. If you don’t already have a Buffer then get one and be sure to choose the right one.