Αυτό που περιγράφεις είναι δεδομένο και σχετίζεται άμεσα μ' αυτό που σου έγραψα (δυστυχώς δεν έχω κρατήσει εκείνο το άρθρο)
δες εδώ http://www.geofex.com/tubeampfaq/taffram.htm
Are Tube Amps louder than solid state amps of the same power?
No. However they do SOUND louder. Let me explain.
Some excellent scientific work on tube preamplifiers and their distortion products has turned up the mechanism for this. When tubes are driven outside their linear region, for the first 12db or so of overdrive the harmonics that they produce trick the human ear into thinking that the sounds are getting louder, when in fact the sound is getting progressively more distorted.
It is this acoustic trick that can make tube amps sound up to 12db louder than they actually are compared to a perfect, undistorted amplifier. A solid state amplifier of the same power as a tube amp may distort at the same signal level as the tube amp, but the distortions are not subtle, and we hear them as distortion, not as a slightly louder sound. A solid state amplifier of much greater power would remain undistorted at higher levels, and the tube amp would sound comparably loud to the larger solid state amp.
They sound larger than they are.
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ΕΠΙΣΗΣ για πολύ μεγαλύτερη ανάλυση δες και τις σελίδες 36-49 εδώ, πιστεύω πως αυτό το υλικό το έχει αντιγράψει ο τύπος από εκείνο το άρθρο που αναφέρθηκα πριν, μου το θυμίζει πάρα πολύ
http://www.google.gr/url?q=http://www.guitaramplifierblueprinting.com/Tubeprimerandselection320-2.pdf&sa=U&ei=X7IlT6T5PMfh8AObuMHMBw&ved=0CBMQFjABOAo&sig2=SS2f8_yDsgjMmSNbgfrrlw&usg=AFQjCNFZ5FJa_-2ZIR9kLLWujfIz9r1C6Q
Ενδεικτικά:
Vacuum-tube amplifiers differ from transistor and operational amplifiers because they can be operated in the overload region without
adding objectionable distortion. The combination of the slow rising edge and the open harmonic structure of the overload characteristics form an almost ideal sound- recording compressor. Within the 15-20 dB "safe" overload range, the electrical output of the tube amplifier increases by only 2-4 dB, acting like a limiter. However, since the edge is increasing within this range, the subjective loudness remains uncompressed to the ear. This effect causes tube-amplified signals to have a high apparent level which is not indicated on a volume indicator (VU meter). Tubes sound louder and have a better signal-to-noise ratio because of this extra subjective head room that transistor amplifiers do not have.