Electric Guitar Distortion


	Contents:
	Audio sheet
	Exercise sheet
	Explanation

Electric guitar distortion is a traditional field of audio effects. In its simple form it means hard or soft clipping the signal. Clipping a signal is a form of signal distortion, in the context of audio effects sometimes also called overdrive. Overdrive or distortion will produce many strong harmonics. The distortion may be generated already before power amplification from an external effect pedal or inside the power amplifier (esp. with tube amplifier). Finally the already distorted and amplified signal is fed into loudspeakers installed in a cabinet. The loudspeaker(s) (incl. cabinet) may again distort the signal and also will introduce linear frequency range limitations and resonances (linear filtering). Resonances may result from guitar speaker itself and/or from the cabinet (open backside). More details can be found here.

Special Thanks

Special thanks go to Dr. Philipp Bulling. He played the guitar and allowed to use the audio example for manipulations purposes.

Playback Type

Both, standard loudspeaker and headphone playback is possible.

Audio Examples

We are delighted to announce that Marten Finck has been awarded the GaS prize for his Master's thesis on "Evaluation of Speech Quality Using Machine Learning".

In his work, he investigated possible side effects of magnetic resonance-guided focussed ultrasound treatment (MRgFUS) on speech quality in patients with neurological diseases such as Parkinson's disease and essential tremor. This innovative and non-invasive treatment method is used to reduce tremor, i.e. the shaking of limbs.

To evaluate the effects on speech, pre- and post-operative speech recordings of 56 patients were analysed: Speech quality was assessed in five categories (monotony, clarity, fluency, auditory effort and vocal tremor) through a survey with 21 participants and used to create a convolutional neural network (CNN). This generates an objective assessment of speech quality using mel frequency cepstral coefficients (MFCCs), fundamental frequency and loudness. A mean absolute error (MAE) of 0.81 on a scale of 0 to 10 was achieved, compared to a standard deviation of 0.67 for the survey participants compared to a reference assessment. The evaluation of the survey revealed minor positive and negative changes in speech quality, which were balanced overall and tended to indicate natural speech variations in connection with the patients' underlying illnesses.

Congratulations on this well-deserved honour!