For guitarists diving into the world of amp modeling and profiling, the question of speaker cabinets often leads to a fork in the road: FRFR or GRFR? If you’re considering a Kemper Profiler, Fractal Axe-Fx, or similar modeler, understanding the nuances between these cabinet types is crucial to unlocking the full potential of your gear. Let’s explore why a Full Range Flat Response (FRFR) Guitar Amp Cabinet might be more essential than you think, especially when it comes to faithfully reproducing the sound of your meticulously crafted amp and cabinet profiles.
Understanding FRFR vs. GRFR: What’s the Real Difference?
You’ve likely encountered the terms FRFR (Full Range Flat Response) and GRFR (Guitar Range Flat Response). The core distinction lies in the frequency range each type of cabinet is designed to reproduce accurately. FRFR systems, as the name suggests, aim for a flat response across a broad frequency spectrum, ideally mirroring the entire range of human hearing (20Hz – 20kHz). In practical terms for audio equipment, this often translates to a more realistic range of 40Hz – 15kHz.
GRFR cabinets, on the other hand, are designed with a more limited frequency range, tailored to the typical frequency range of a guitar speaker. Some manufacturers offer GRFR options by modifying FRFR cabinets, like bypassing the tweeter in a standard FRFR or using DSP to limit the frequency response.
The crucial point is that traditional guitar amp cabinets and speakers are not flat response. They have a limited frequency range, particularly in the high end, with a significant roll-off typically starting around 5-6kHz.
Why FRFR Matters for Guitar Amp Modeling and Cabinet Profiles
If amp modelers and profilers are designed to replicate guitar amps and cabinets – which inherently use non-flat, guitar-range speakers – why is FRFR even in the conversation? This is a valid question, and the answer lies in maximizing the capabilities of your amp modeler, especially regarding cabinet profiles.
Think about the tonal equation: a significant portion of a guitar amplifier’s overall sound, estimated around 75%, comes from the speaker cabinet. This becomes clear when you experiment by playing different amp heads through the same guitar cabinet – they will sound surprisingly similar. Conversely, using one amp head with various cabinets reveals dramatically different tonal characteristics.
This is where FRFR systems truly shine. An FRFR monitor is engineered to reproduce the input signal as accurately as possible. This means it can faithfully reproduce the unique frequency response captured in your Kemper or modeler’s cabinet profiles. By using an FRFR cabinet, you are leveraging the modeler’s ability to recreate the sonic fingerprint of specific guitar speaker cabinets, without the limitations of a traditional guitar speaker.
There’s a common misconception, sometimes fueled by misguided online demonstrations, that you can simply EQ a guitar speaker to make it FRFR. One example often cited involves using an external EQ to flatten the frequency response of a guitar speaker. However, this approach is fundamentally flawed. While EQ can attenuate peaks in the frequency response, it cannot magically create frequencies that a guitar speaker is incapable of reproducing. Boosting “valleys” in the frequency response curve to approximate flatness introduces artificial artifacts and distortions. You are not transforming a guitar speaker into a full-range system; you are merely applying a limited EQ correction within its restricted frequency range.
The Unsung Importance of High Frequencies in Guitar Tone
While “flatness” and neutral reproduction are important aspects of an FRFR system, they are not the only considerations. A significant portion of the unique tonal characteristics and harmonic content of any amp-guitar speaker combination exists above 5kHz – frequencies that traditional guitar speakers struggle to reproduce accurately. These higher frequencies contribute significantly to the “fingerprint” of a particular amp-cabinet setup. The ability of an FRFR system to reproduce these higher frequencies accurately is just as crucial as its overall neutrality.
This becomes even more apparent with cleaner guitar tones. Clean tones are typically less compressed and possess a wider frequency response than high-gain tones. If you aim to reproduce pristine clean tones or even venture into acoustic guitar modeling with your Kemper or similar device, an FRFR system becomes not just preferable, but essential.
FRFR: Unlocking Versatility and Accuracy
In conclusion, while GRFR cabinets might seem like a bridge between traditional guitar cabinets and FRFR, they ultimately represent a compromise. For guitarists committed to harnessing the full potential of amp modeling and cabinet profiling, particularly with devices like the Kemper Profiler, a true FRFR system offers unparalleled flexibility and accuracy. It allows you to experience the nuances of your carefully crafted profiles, from the deepest lows to the shimmering highs, ensuring that you hear exactly what your modeler is designed to deliver. For maximum versatility across various tones and genres, and to truly unlock the power of cabinet profiles, FRFR is the clear choice.
