The Barge Concepts BP-1 is an enhanced implementation of a vintage Interfax HP-1 Harmonic Percolator® - reverse engineered from photos of a vintage unit posted on various music/gear forums in 2005. The HP-1 is a legendary fuzz/overdrive effect that was designed to enhance pleasing harmonics while suppressing the less pleasing ones. Vintage versions of the HP-1 are nearly impossible to find, and the modern-era copies just aren't the same.
To the original HP-1 design we've added a high impedance, 0-20 dB gain input buffer with footswitch-operated true bypass, and a low impedance output buffer with dual internal micro slide-switches for true bypass. An overall 3PDT true bypass footswitch is also provided, and dual color, Blue/Red LEDs indicate all foot switch states.
The BP-1 with its input and output buffers disabled is a highly accurate replica of the original Interfax HP-1, including some recently-discovered circuit specifics. In this ‘stock' configuration, the BP-1 offers input level (Harmonics) and output volume (Balance) controls, exactly duplicating the function of the originals.
With the input buffer active and the gain (Drive) turned up, the unit takes on a new character, while retaining the touch-sensitivity of the un-amped setup. Dial up the gain and use the Harmonics control to get everything from a mild boost to outrageous grit. The wide dynamic range of effect makes a wealth of sounds available from your volume control.
The output buffer is provided for those situations when you're driving difficult loads; low impedance inputs on amplifiers or vintage effects, high capacitance cables, long cable runs, etc. The buffer is extremely accurate, and for the majority of situations, we recommend leaving it on. But if you're looking for a specific interaction with another effect that depends on the straight passive output character of the HP-1, a flick of the internal switches is all you need.
For those who want or need more output level than an HP-1 normally provides, custom modifications to the BP-1 (new in v2) now allows the output buffer of the unit to be built with a fixed gain of +5, +10, or +15 dB, and for those who believe everything should be adjustable, a fourth pot can be added to the front panel to allow the full +15 dB range of adjustment. The output gain is intentionally limited to no more than +15 dB so that the output buffer remains in a highly linear mode, and never goes into hard clipping. That means that what you see at the output is just a higher-amplitude version of what you'd get without the gain - the same tonal characteristics, just louder.
Even though it costs more, we generally recommend that, if you feel you need more gain, make it variable. If you choose a fixed gain, you also increase the noise level by about the same amount without the ability to turn it down (except by going into output bypass mode). It's an unfortunate byproduct of gain, but being able to turn it down when you don't need it will definitely reduce the overall noise in your system. Also, be aware that under most circumstances the HP-1 produces a pretty respectable output level, definitely on a par with the rest of the effect world. It therefore makes sense to be reasonably sure you need the additional output level before ordering a unit with the extra gain. Of course, there's no harm (and no noise problem) in having a variable-gain unit and leaving it set to unity gain - you never know when a few more dB of level might come in handy.
The BP-1 contains all of the usual Barge Concepts features; 3PDT true bypass, dual color LEDs, 4 layer silkscreened and solder-masked circuit board, quality components throughout, and a price tag that's a lot easier on your budget.
Now's the time to add a legendary unit to your pedalboard.
- (2010-06-14) Barge Concepts BP-1 Test And Comparison With Shellac's Steve Albini by GearWire
- (2010-06-14) Barge Concepts BP-1: The Gearwire Stombox Walkthrough by GearWire
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