What is a treble bleed on your guitar? Do you need one? Is it expensive?
These are great questions and we get asked them quite a bit. Let's start by defining what a treble bleed is, types of treble bleeds, and how they work. They are a solution to a problem that has been around since the earliest electric guitars.
The Problem: As you turn the volume down on your guitar, the treble reduces at a greater rate than the overall volume. The tone gets darker as you turn your volume down. If you want a uniform tone as you roll off your volume, this is a big issue. Many players do not mind the treble loss, but it can be very frustrating for others
The Solution: A treble bleed circuit allows you to compensate the treble loss by filtering bass frequencies out. This gives the perception that the tone is more even as you roll down. This is a totally passive system and does not add anything, but takes away lower frequencies. There is no change at all when the volume is all the way up.
A treble bleed is a circuit that goes on the volume potentiometer(s) of your guitar between the input and output lugs. On a volume potentiometer, one lug is grounded and the other two serve as an input and output. There are a few different approaches to the treble bleed circuit, but all are inexpensive and relatively easy to install.
The 3 types of treble bleed circuits are as follows:
1. Capacitor only: This is a classic and does have its flaws. In this circuit, you simply install a capacitor between the in and out lugs of the volume potentiometer. The capacitor will filter some bass frequencies. The only drawback is it may be too extreme and make the guitar sound "thin" in some cases. A value of between 160pf and 200pf is best in most cases.
2. Capacitor and resistor in parallel: Big improvement here as the resistor helps keep the treble in check so it does not become overpowering. Unfortunately, this setup does affect the taper of the volume potentiometer, so it may not be a useful to you. Since the resistor determines the treble roll off to counter the bass filtering by the cap, the values need to be correct to function properly. A resistor with the values 100k, 150k, 220k, or 300k should mate to a capacitor valued at 1000pf, 2000pf, 470pf, or 560pf respectively. These will yeild acceptable results, but tweak away! You cannot damage anything other than by overheating components.
3. Capacitor and resistor in series: This is the best version as far as I am concerned. It addresses the over bright cap only method and the taper issue with the parallel method. The values do need to be correct, but you can pretty well use a 1000pf cap with a 150k resistor on most guitars and get a great result.
All of these are less than a few dollars in components and you do not need any special brand or type. They won't impact your tone. You only need the right values.
Now you know what it is, how it works, and that the cost is just a few dollars. So, do you need one? Why not just try it and see? This very well may be the least expensive mod you ban do to your electric guitar and it is completely reversible.