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Are there any tutorials online about tube amps? I have to admit I am at a total loss when you guys start talking about 300B, SET, EL84, triode, et al.I'm a newbie, any assistance will be greatly appreciated. I am using Tekton Lore 98db @1w 8 Ohms
SIGNIFICANCE OF MUSICAL HARMONICSHaving divided amplifiers into three groups of distortion characteristics,the next step is to determine how the harmonics relate to hearing. There is a close parallel here between electronic distortion and musical tone coloration that is the real key to why tubes and transistors sound different. Perhaps the most knowledgeable authorities in this area are the craftsmen who build organs and musical instruments [8] [9]. Through many years of careful experimentation these artisans have determined how various harmonics relate to the coloration of an instrument's tonal quality.The primary color characteristic of an instrument is determined by the strength of the first few harmonics. Each of the lower harmonics produces its own characteristic effect when it is dominant or it can modify the effect of another dominant harmonic if it is prominent. In the simplest classification, the lower harmonics are divided into two tonal groups. The odd harmonics (third and fifth) produce a "stopped" or "covered" sound. The even harmonics (second, fourth, and sixth) produce "choral" or "singing"sounds.The second and third harmonics are the most important from the viewpoint of the electronic distortion graphs in the previous section. Musically the second is an octave above the fundamental and is almost inaudible; yet it adds body to the sound, making it fuller. The third is termed a quint or musical twelfth. It produces a sound many musicians refer to as"blanketed." Instead of making the tone fuller, a strong third actually makes the tone softer. Adding a fifth to a strong third gives the sound a metallic quality that gets annoying in character as its amplitude increases. A strong second with a strong third tends to open the "covered"effect. Adding the fourth and the fifth to this changes the sound to an"open horn" like character.The higher harmonics, above the seventh, give the tone "edge" or "bite."Provided the edge is balanced to the basic musical tone, it tends to reinforce the fundamental, giving the sound a sharp attack quality. Many of the edge harmonics are musically unrelated pitches such as the seventh,ninth, and eleventh. Therefore. too much edge can produce a raspy dissonant quality. Since the ear seems very sensitive to the edge harmonics,controlling their amplitude is of paramount importance. The previously mentioned study of the trumpet tone [6] shows that the edge effect is directly related to the loudness of the tone. Playing the same trumpet note loud or soft makes little difference in the amplitude of the fundamental and the lower harmonics. However. harmonics above the sixth increase and decrease in amplitude in a1most direct proportion to the loudness. This edge balance is a critically important loudness signal for the human ear.
