The Vein-Tap.com Leech is a small passive volume attenuator pedal from Vein-Tap.com. The maker describes it as "essentially an external volume control for your guitar", a way to turn your amp down without losing the character of a driven lead tone. Vein-Tap.com says it can "bleed a range beautiful crunchy or clean tones out of a lead tone", giving an amp what the maker calls a whole new dimension at lower volume.1
Placement: effects loop only
The Leech is strictly an effects loop device. Vein-Tap.com states in capitals on the product page: "THE LEECH IS NOT A POWER ATTENUATOR. It is not designed for use between your amp and cab, so please never use it there."1 Ben from Vein-Tap.com puts the same warning more bluntly in the company's support article: "NEVER put a Leech between your amp and speaker cabinet. You'll destroy your Leech, and could even damage your amp."2
The reason is the difference between a line-level volume control and a power attenuator. The Leech sits in the low-level signal path after your amp's preamp, where it acts as a master volume. Put it in the loop, right at the end of the effects chain, and it gives you a master volume control for the whole amp.2
A Leech works as a master volume control only with series effects loops. Parallel effects loops will not work.2
For amps with only a parallel loop, Ben from Vein-Tap.com offers one exception: a Leech "can be placed in front of the amp when used with a parallel loop", where he says "a Leech still makes your tone awesome put in front of the amp!"2
Power and bypass
Because the circuit is passive, the Leech needs no power supply and no battery. Vein-Tap.com says there is no room inside for a battery, and that the pedal is "totally passive just like any kind of high quality volume potentiometer". It is true bypass, "so it doesn't color the sound when it's off."1 An LED indicator is built in.1
Treble bleed capacitors
Turning a passive volume control down usually dulls the top end. The Leech addresses this directly: treble bleed capacitors are installed as standard in every Leech, so the high frequencies hold up as you dial the level down.1
Passive attenuator versus Power Soak
A passive volume attenuator and a Power Soak solve the same problem, playing a cranked amp quietly, in different ways. The Leech is a passive line-level control for the effects loop; a Power Soak works at the amp's output. Ben from Vein-Tap.com frames the trade-off in cost terms: "When done right, this can be as good a solution as a Power Soak, for a fraction of the cost." His summary of the goal: "juiced tone at bedroom levels, for less than the price of a round of drinks!"2
Specifications
| Specification | Value |
|---|---|
| Type | Passive Volume Guitar Attenuator with LED Indicator |
| Circuit | Totally passive, like a high quality volume potentiometer |
| Bypass | True bypass |
| Power | None required; no room inside for a battery |
| Size | 92 × 38 × 32 mm |
| Weight | 0.25 kg |
| Price | £26.95 GBP (as listed 1 September 2026) |
What the maker says it does
- Acts as "essentially an external volume control for your guitar"1
- Can "bleed a range beautiful crunchy or clean tones out of a lead tone"1
- Gives an amp "a whole new dimension at lower volume"1
- Treble bleed capacitors fitted as standard in every unit1
- Works as a master volume in a series effects loop2
Videos
Vein-Tap.com
Isurus
Light Audio Recording
Questions
Does the Vein-Tap Leech need a battery or power supply?
No. The Leech is totally passive, working like a high quality volume potentiometer, so it needs no power at all. Vein-Tap.com notes there is no room inside for a battery, and the pedal is true bypass, so it does not color the sound when it is off.
Is the Vein-Tap Leech true bypass?
Yes. Vein-Tap.com states the Leech is true bypass, so it does not color the sound when it is off. Because the circuit is passive, it also runs without any battery or power supply.
Can you put the Vein-Tap Leech between the amp and the cab?
No. Vein-Tap.com is explicit that the Leech is not a power attenuator and is not designed for use between your amp and cab. The maker warns that putting it there will destroy the Leech and could even damage your amp. It belongs in the effects loop only.
Can the Leech go in front of the amp?
Only in a limited case. A Leech works as a master volume control only with series effects loops, and parallel loops will not work. Ben from Vein-Tap.com says a Leech can be placed in front of the amp when used with a parallel loop, which is the workaround for amps without a series loop.
What does a treble bleed capacitor do in a passive attenuator?
Turning a passive volume control down tends to dull the high frequencies. A treble bleed capacitor lets treble pass around the volume control as it is turned down, keeping the tone from going muddy. Vein-Tap.com installs treble bleed capacitors as standard in every Leech.
How is a passive volume attenuator different from a Power Soak?
A passive volume attenuator like the Leech is essentially an external volume control for your guitar signal, with no electronics or power. A Power Soak handles the amp's output power. Ben from Vein-Tap.com says a passive attenuator done right can be as good a solution as a Power Soak, for a fraction of the cost.
Sources (2)
- The Leech Passive Volume Guitar Attenuator, Vein-Tap.com, 2026-09-01
- Can I Use a Volume Attenuator in My Effects Loop?, Vein-Tap.com, 2012-06-10
