Heart Muller (bass & lead OD) with demo


SS.org Regular
Feb 14, 2018
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Heart Müller, a true bypass pedal, originally was developed to be a bass overdrive. However, this latest version was tweaked in order to be used by a six-string as well. The accompany demo video focuses on the bass in the first half, with a rhythm/lead/bass composition to showcase the results of Heart Müller in a mix.

I would consider this a low to moderate gain pedal, which is more than sufficient for bass or crunch/hi-gain rhythm/lead guitar. For a very clean rhythm channel, it adds some aggression, but nothing excessive. For rhythm/lead, it is easier to dial into the right amount of drive, since there seems to be a sweet spot (at least with my gear). For bass, however, the range of tone seems to be far more expressive and broader. I’m able to achieve tones that resemble a fretless bass, a classic rock bass, a jazz bass, a metal bass, etc. And although the Heart Müller does make rhythm/lead stand out better in a mix, it really makes a bass pop with clarity.

Heart Müller has the basic VOLUME and DRIVE controls, both of which need to be balanced for proper output levels, viz., the more DRIVE you have, the more the VOLUME needs to be toned down (unless looking to use it as a boost). The KLANG control provides either high or low-cut of the frequency. At 12-noon the EQ is flat (although with DRIVE all the way down and MIX all the way up, the tone is livelier and clearer, even with KLANG set at 12-noon). If you turn the KLANG toward to the left, you cut the highs, thereby increasing bass response. Conversely, turning the knob to the right increases highs and decreases lows. This allows for a very deep (yet clear) thunderous bass, or one that is very bright and punchy.

Now, the signal is buffered and split into two signals, one wet and one dry. This is controlled by the MIX knob, and when turned all the way left, the signal is hardly affected by Heart Müller (a touch more clarity due to the buffering). As you turn the knob to the right, you integrate more of Heart Müller into your original signal. This increases Heart Müller’s diversity significantly, and so, the demo video does go through various settings at full MIX, but also varying combinations of the settings (including low to moderate MIX) as I present my favorite settings.

Heart Müller is a very impressive pedal. Yes, I like it with rhythm/lead, but love it for bass. Hand-built in Sweden, at an approximate price of $200 USD, if you want your instruments to cut through the mix better, while being able to customize your tone in subtle to broad sweeps, Heart Müller should be a serious consideration. For some time, I’ve relied on pre-created bass lines in my backing track program, but always found the lines a touch boring, not very melodic and they tend to blend and get lost in the mix. Recently, since acquiring a Busuyi bass, I’ve been composing my own bass lines, and do they ever cut through with the Heart Müller. Listen to the second composition on the demo video, and you will hear lucidly what I mean.