Achieving The Oberheim Filter Growl A Comprehensive Guide
Introduction: Understanding the Oberheim Sound
The Oberheim filter growl is a distinctive sound, synonymous with the rich and powerful analog synthesizers crafted by Oberheim Electronics. This unique sonic signature has captivated musicians and producers for decades, gracing countless iconic tracks across genres ranging from progressive rock to electronic dance music. To truly understand how to achieve this coveted sound, it’s essential to delve into the core characteristics of Oberheim synthesizers and the specific filter designs that contribute to their growling character.
The essence of the Oberheim sound lies in its boldness, warmth, and a certain aggressive edge. This is largely attributed to the discrete circuitry used in their early instruments, which imparted a raw and organic quality to the sound. Unlike integrated circuits (ICs), discrete components like transistors and resistors offer a slightly imperfect signal path, resulting in subtle harmonic distortions and a complex tonal palette. These imperfections, far from being flaws, are the very essence of the Oberheim magic. The filters, in particular, play a crucial role in shaping this sonic character. Oberheim synthesizers typically employ 12dB/octave or 24dB/octave low-pass filters, often based on the legendary State Variable Filter design. This design allows for a wide range of tonal possibilities, from smooth and creamy to gritty and resonant. The resonance control, in particular, is a key element in achieving the signature Oberheim growl. When the resonance is cranked up, the filter emphasizes frequencies around the cutoff point, creating a pronounced peak that can add a vocal-like quality to the sound. This peak, when pushed to its limits, is where the growl truly comes alive.
Exploring the history of Oberheim synthesizers is also crucial to understanding their sound. Instruments like the SEM (Synthesizer Expander Module), the OB-X series (OB-X, OB-Xa, OB-8), and the Matrix series (Matrix-12, Matrix-6) are all renowned for their distinctive filter characteristics. Each of these instruments offers a slightly different flavor of the Oberheim sound, but they all share a common thread of sonic excellence. The SEM, for instance, is known for its versatile multimode filter, capable of low-pass, high-pass, band-pass, and notch filtering. This flexibility allows for a wide range of sonic textures, making it a favorite among sound designers. The OB-X series, on the other hand, is celebrated for its fat and powerful sound, particularly its resonant low-pass filter. The Matrix series takes things further with its advanced modulation capabilities, allowing for complex and evolving filter sweeps. By understanding the nuances of these different instruments, you can gain a deeper appreciation for the Oberheim sound and how to recreate it.
Ultimately, achieving the Oberheim filter growl is not just about replicating a specific filter design. It's about understanding the interplay of all the components within the synthesizer and how they contribute to the overall sound. It's about experimenting with different waveforms, modulation routings, and filter settings to find that sweet spot where the growl emerges. It's also about embracing the imperfections and quirks of analog circuitry, which are often the source of the most interesting and unique sounds. So, dive in, experiment, and let the Oberheim filter growl inspire your sonic creations.
Key Elements for Achieving the Oberheim Filter Sound
To effectively emulate the Oberheim filter growl, several key elements need careful consideration. These elements range from the fundamental building blocks of sound synthesis, such as oscillators and waveforms, to the specific characteristics of the filter itself and how it's modulated. Understanding each of these elements and how they interact is crucial for achieving that signature Oberheim sound.
First and foremost, the choice of oscillators and waveforms plays a significant role. Oberheim synthesizers are known for their rich and harmonically complex waveforms, which provide a solid foundation for the filter to sculpt. Sawtooth waves, in particular, are a favorite for achieving the growl, as their bright and harmonically rich character interacts beautifully with the resonant filter. Pulse waves, with their adjustable pulse width, can also be used to create a variety of interesting timbres, from thin and reedy to thick and throaty. Experimenting with different combinations of waveforms, such as mixing a sawtooth wave with a square wave or a pulse wave, can further enhance the sonic complexity and create a more layered sound. The detuning of oscillators, a common technique in synthesis, can also add a lush and vibrant quality to the sound, making the filter growl even more pronounced.
The filter itself is, of course, the heart of the Oberheim growl. As mentioned earlier, Oberheim synthesizers typically employ 12dB/octave or 24dB/octave low-pass filters, often based on the State Variable Filter design. The key to the growl lies in the filter's resonance control. Resonance, also known as feedback or emphasis, boosts the frequencies around the filter's cutoff point. When the resonance is set high, the filter begins to self-oscillate, creating a pronounced peak that can sound almost vocal-like. This peak is what gives the Oberheim filter its signature growl. The cutoff frequency, which determines the point at which the filter begins to attenuate frequencies, is another crucial parameter. By sweeping the cutoff frequency, either manually or with a modulation source, you can create dynamic and expressive filter effects.
Modulation is the third key element in achieving the Oberheim filter growl. Modulating the filter cutoff frequency with an LFO (Low-Frequency Oscillator) or an envelope can create rhythmic pulsations, sweeping textures, and other dynamic effects. An LFO can be used to create a constant, repeating modulation, while an envelope can be used to create a more transient modulation, such as a filter sweep that follows the amplitude of the note. Experimenting with different modulation sources and routings can lead to a wide range of interesting sounds. For example, using a sawtooth LFO waveform to modulate the filter cutoff can create a distinctive ripping sound, while using an envelope with a slow attack and decay can create a smooth and evolving filter sweep. Additionally, modulating the resonance can also add another layer of expressiveness to the sound. Subtle modulations of the resonance can add a subtle warmth and character, while more extreme modulations can create dramatic and unpredictable effects.
In summary, achieving the Oberheim filter growl requires a careful consideration of oscillators, waveforms, the filter itself, and modulation techniques. By understanding how these elements interact, you can unlock the full potential of your synthesizer and create sounds that are both powerful and expressive. The key is to experiment, explore, and let your ears guide you.
Step-by-Step Guide to Programming the Growl
Programming the Oberheim filter growl is an art form, a delicate balance between oscillator selection, filter manipulation, and modulation mastery. This step-by-step guide will walk you through the process, providing practical tips and techniques to help you achieve that coveted Oberheim sound. Whether you're using a vintage Oberheim synthesizer, a modern analog recreation, or a software emulation, the principles remain the same. Let's embark on this sonic journey and unlock the secrets of the growl.
Step 1: Oscillator Selection and Waveform Shaping. Start by selecting your oscillators and waveforms. As mentioned earlier, sawtooth waves are an excellent starting point for the Oberheim growl due to their rich harmonic content. However, don't be afraid to experiment with other waveforms, such as square waves or pulse waves, to add different textures and timbres to your sound. If your synthesizer has multiple oscillators, try layering them together, detuning them slightly to create a thicker, more vibrant sound. This detuning adds a subtle beating effect that can enhance the growl. Adjust the levels of the oscillators to find the right balance. A good starting point is to have the oscillators at roughly equal levels, but you can experiment with boosting or cutting certain oscillators to shape the overall tone.
Step 2: Filter Configuration and Resonance. Next, focus on the filter. Select a low-pass filter with a slope of either 12dB/octave or 24dB/octave, depending on your preference and the capabilities of your synthesizer. The 24dB/octave filter will typically provide a steeper cutoff and a more pronounced resonance peak, while the 12dB/octave filter will offer a smoother, more subtle effect. Now, the crucial step: adjust the resonance. Start by setting the resonance to a moderate level, around 50-70%, and then gradually increase it while playing a note. You'll hear the filter start to emphasize frequencies around the cutoff point, creating a peak that adds a vocal-like quality to the sound. As you increase the resonance further, the filter will begin to self-oscillate, producing a pure sine wave tone at the cutoff frequency. This is where the growl truly comes alive. Be careful not to push the resonance too high, as it can result in an overly harsh or piercing sound. The key is to find the sweet spot where the growl is present but not overwhelming.
Step 3: Cutoff Frequency and Modulation. The next step is to adjust the cutoff frequency and explore modulation options. The cutoff frequency determines the point at which the filter begins to attenuate frequencies. By sweeping the cutoff frequency, you can create dynamic and expressive filter effects. Start by setting the cutoff frequency relatively low, so that the sound is muffled and bassy. Then, slowly increase the cutoff frequency while playing a note. You'll hear the sound gradually brighten up as more high frequencies pass through the filter. Now, it's time to add modulation. Use an LFO (Low-Frequency Oscillator) or an envelope to modulate the filter cutoff frequency. An LFO can create rhythmic pulsations and sweeping textures, while an envelope can create a more transient modulation, such as a filter sweep that follows the amplitude of the note. Experiment with different LFO waveforms (sine, triangle, square, sawtooth) and different envelope shapes (attack, decay, sustain, release) to achieve a variety of effects. For a classic Oberheim growl, try using a sawtooth LFO waveform with a moderate rate to create a ripping sound. Alternatively, use an envelope with a slow attack and decay to create a smooth and evolving filter sweep. You can also modulate the resonance to add another layer of expressiveness to the sound. Subtle modulations of the resonance can add a subtle warmth and character, while more extreme modulations can create dramatic and unpredictable effects.
By following these steps and experimenting with different settings, you'll be well on your way to programming the signature Oberheim filter growl. Remember, the key is to listen carefully and let your ears guide you. Don't be afraid to try new things and explore the sonic possibilities of your synthesizer.
Advanced Techniques and Tips for a Unique Growl
Once you've mastered the basics of programming the Oberheim filter growl, it's time to delve into advanced techniques and tips to create a truly unique and captivating sound. These techniques involve exploring unconventional modulation routings, utilizing effects processing, and embracing the quirks and imperfections of analog circuitry. By pushing the boundaries of traditional synthesis methods, you can unlock a whole new world of sonic possibilities and craft a growl that is distinctly your own.
One advanced technique is to experiment with complex modulation routings. Instead of simply modulating the filter cutoff with a single LFO or envelope, try using multiple modulation sources simultaneously. For example, you could use an LFO to modulate the filter cutoff, an envelope to modulate the resonance, and a second LFO to modulate the first LFO's rate. This creates a complex and evolving modulation pattern that can add a lot of interest and depth to the sound. Another powerful technique is to use the keyboard tracking feature of your synthesizer to modulate the filter cutoff. This means that the cutoff frequency will change depending on the note you play, allowing you to create sounds that are brighter in the higher registers and darker in the lower registers. You can also use velocity sensitivity to modulate the filter cutoff, so that playing the keys harder will result in a brighter sound.
Effects processing can also play a crucial role in shaping the Oberheim filter growl. Adding a touch of distortion or overdrive can enhance the harmonic content and make the growl more aggressive and biting. Experiment with different types of distortion, from subtle tube saturation to crunchy overdrive, to find the sound that works best for your needs. Reverb and delay can also be used to add space and depth to the sound, making the growl sound more expansive and atmospheric. Try using a short, subtle reverb to add a touch of warmth and character, or a longer delay to create rhythmic echoes and textures. Chorus and phaser effects can also be used to add movement and animation to the sound. A subtle chorus can add a lush and shimmering quality, while a phaser can create a swirling and psychedelic effect.
Finally, embracing the quirks and imperfections of analog circuitry is essential for achieving a truly authentic Oberheim growl. Analog synthesizers are not perfect machines; they have their own unique quirks and characteristics that contribute to their sound. These imperfections, far from being flaws, are often the source of the most interesting and unique sounds. For example, the slight instability of analog oscillators can add a subtle detuning effect that makes the sound more vibrant and alive. The non-linear response of analog filters can create subtle harmonic distortions that add character and warmth. By embracing these imperfections, you can create a growl that is full of character and personality.
In conclusion, achieving a truly unique Oberheim filter growl requires a combination of technical skill, creative experimentation, and a willingness to embrace the unexpected. By exploring advanced modulation techniques, utilizing effects processing, and embracing the quirks of analog circuitry, you can unlock a world of sonic possibilities and create a growl that is distinctly your own. So, don't be afraid to push the boundaries, experiment with new ideas, and let your ears guide you on your sonic journey.
Emulating the Oberheim Sound in Software
While vintage Oberheim synthesizers are highly sought after for their iconic sound, they can be expensive and difficult to maintain. Fortunately, numerous software emulations are available that capture the essence of the Oberheim filter growl with remarkable accuracy. These virtual instruments offer a cost-effective and convenient way to access the Oberheim sound, allowing you to create growling basses, searing leads, and lush pads without the need for vintage hardware. In this section, we'll explore some of the best software emulations and discuss techniques for achieving the Oberheim growl in the digital realm.
Several software developers have created excellent emulations of classic Oberheim synthesizers. Arturia's SEM V, for example, is a faithful recreation of the legendary Oberheim SEM (Synthesizer Expander Module), known for its versatile multimode filter and rich sound. GForce Software's OB-E is another highly regarded emulation, capturing the essence of the iconic Oberheim OB-X series synthesizers. These virtual instruments meticulously model the circuitry of the original hardware, replicating the nuances and imperfections that contribute to the Oberheim sound. They often include additional features and enhancements, such as expanded modulation options, effects processing, and polyphony, making them even more powerful than the originals.
When using software emulations to achieve the Oberheim filter growl, the same principles apply as with hardware synthesizers. Start by selecting the appropriate waveforms, such as sawtooth waves or pulse waves, and layering them together to create a rich and harmonically complex sound. Then, focus on the filter. Most software emulations offer a variety of filter types, but the key to the Oberheim growl is the resonant low-pass filter. Adjust the resonance to create a pronounced peak around the cutoff frequency, and then sweep the cutoff frequency with an LFO or an envelope to create dynamic and expressive filter effects. Don't be afraid to push the resonance to its limits to achieve that signature growl. Experiment with different modulation routings and effects processing to further shape the sound. Software emulations often offer a wider range of modulation options than their hardware counterparts, allowing you to create complex and evolving textures. You can also use built-in effects, such as distortion, reverb, and chorus, to add warmth, space, and character to the sound.
One advantage of using software emulations is the ability to save and recall your patches, making it easy to recreate your favorite sounds. You can also use software sequencers and DAWs (Digital Audio Workstations) to create complex arrangements and automate parameters, such as filter cutoff and resonance, in real-time. This allows you to create dynamic and evolving soundscapes that would be difficult to achieve with hardware synthesizers alone.
In addition to dedicated Oberheim emulations, many general-purpose software synthesizers offer the necessary tools to create the Oberheim filter growl. Synthesizers like Native Instruments Massive, Xfer Records Serum, and Spectrasonics Omnisphere have powerful filters and modulation options that can be used to emulate the Oberheim sound. The key is to understand the principles of subtractive synthesis and how the filter interacts with the oscillators and modulation sources. By experimenting with different settings and techniques, you can achieve a wide range of sounds, including the coveted Oberheim growl.
In conclusion, software emulations provide an excellent way to access the Oberheim sound without the expense and hassle of vintage hardware. By using dedicated Oberheim emulations or general-purpose software synthesizers, you can create growling basses, searing leads, and lush pads that capture the essence of the Oberheim filter growl. Remember to experiment with different settings, modulation routings, and effects processing to find your own unique voice. The possibilities are endless.
Conclusion: Mastering the Oberheim Growl
In conclusion, mastering the Oberheim filter growl is a journey that combines technical understanding, creative exploration, and a deep appreciation for the unique sonic characteristics of Oberheim synthesizers. From understanding the core elements of the sound, such as oscillator selection, filter configuration, and modulation techniques, to exploring advanced techniques and utilizing software emulations, there are many avenues to pursue in your quest for the perfect growl. By following the steps outlined in this guide and experimenting with your own unique ideas, you can unlock the full potential of your synthesizers and create sounds that are both powerful and expressive.
The key to achieving the Oberheim filter growl lies in understanding the interplay between the different components of the synthesizer. The oscillators provide the raw material, the filter shapes the sound, and the modulation adds movement and expression. By carefully balancing these elements, you can create a sound that is both rich and dynamic. Remember to experiment with different waveforms, filter settings, and modulation routings to find the sweet spot where the growl truly comes alive. Don't be afraid to push the resonance to its limits, but be mindful of the overall balance of the sound. A well-crafted growl should be both aggressive and musical, with a character that is both distinctive and pleasing.
Software emulations offer a convenient and cost-effective way to access the Oberheim sound, allowing you to create growling basses, searing leads, and lush pads without the need for vintage hardware. Many excellent emulations are available that capture the essence of classic Oberheim synthesizers with remarkable accuracy. However, it's important to remember that software emulations are just tools. The ultimate key to achieving the Oberheim filter growl is your own creativity and skill. By understanding the principles of synthesis and experimenting with different techniques, you can create a sound that is uniquely your own, regardless of the tools you use.
Ultimately, the Oberheim filter growl is more than just a sound; it's a sonic signature, a testament to the ingenuity and craftsmanship of Oberheim Electronics. By mastering this iconic sound, you're not just learning how to program a synthesizer; you're connecting with a rich musical heritage and becoming part of a legacy of sonic innovation. So, dive in, experiment, and let the Oberheim filter growl inspire your musical journey. The possibilities are endless, and the only limit is your imagination.
