hsong@bellcore.bellcore.com (g hugh song) (11/30/90)
I am sure that this topic has been thoroughly dealt with several times already. If so, please email me. What is **TECHNICAL** (proven) merit of hybrid/tube amplifiers over modern all-transistor amplifiers? If you think transistors are better, give me the reason also. Please refrain from telling me that "it simply sounds better". Please give me technical information with references (if possible) I need to update my amplifier sooner or later. (My target is QUAD ESL 63) I usually do not believe myths. But, this time, one audio fanatic, who is an EE as I, led me to dig more information about this. Thanks in advance. and followups to "rec.audio.high-end", please. -hsong- nvuxl!hsong@bellcore.bellcore.com
mikes@iuvax.cs.indiana.edu (Michael Squires) (12/04/90)
In article <7965@uwm.edu> nvuxl!hsong@bellcore.bellcore.com (g hugh song) writes: > >What is **TECHNICAL** (proven) merit of hybrid/tube amplifiers over >modern all-transistor amplifiers? If you think transistors are better, >give me the reason also. Matt Morey, who designed a power amplifer for dB Systems back in the late 70's, used some impedance data taken from my speaker system at that time, a double pair of KLH Nines. These speakers at 20Khz were a half-ohm load, mostly reactive. The amount of current required was phenomenal; a Dyna Stereo 400 connected to these speakers was quickly forced into current limiting with obvious impact on the sound. Tube amplifiers, however, have much nicer overload characteristics into weird loads like this particular ESL. Matt eventually putt enough output devices for a 200 wpc AB amp into their 40 wpc class A amp, which did sound very good. I'm not sure what kind of a load the ESL-63's are, but the Dayton-Wright XG-10's used a complicated passive filter in front of the driver transformer which also caused problems with some solid-state designs. I personally don't see any reason why a new solid-state design can't sound as good or better than a tube design, and lots of reasons why a solid-state design after six months will sound better than a tube amp after six months. On the other hand, on a budget, it is often easier to get a "good" amp that is based on a tube output stage. This is the reason for the demand for used Dyna Stereo 70's and Mark III's (I prefer the Eico HF-87/89, which use a superior driver design). -- Mike Squires (mikes@iuvax.cs.indiana.edu) 812 855 3974 (w) 812 333 6564 (h) mikes@iuvax.cs.indiana.edu 546 N Park Ridge Rd., Bloomington, IN 47408 Under construction: mikes@sir-alan@cica.indiana.edu
ncpjmw@brahms.AMD.COM (Mike Wincn) (12/18/90)
In article <8032@uwm.edu> mikes@iuvax.cs.indiana.edu (Michael Squires) writes: >In article <7965@uwm.edu> nvuxl!hsong@bellcore.bellcore.com (g hugh song) writes: >> >>What is **TECHNICAL** (proven) merit of hybrid/tube amplifiers over >>modern all-transistor amplifiers? If you think transistors are better, >>give me the reason also. [...] >I personally don't see any reason why a new solid-state design can't sound >as good or better than a tube design, and lots of reasons why a solid-state >design after six months will sound better than a tube amp after six months. [...] >Mike Squires (mikes@iuvax.cs.indiana.edu) 812 855 3974 (w) 812 333 6564 (h) I don't have much direct experience with tube amps, so the most I can relate is anecdotal. I've been told, and have reason to believe, that the biggest difference between tube and transistor amps is that tube amps go into "soft" clipping when over-driven and transistor amps go into "hard" clipping under those conditions. And that the "hard" clipping sounds more harsh than does "soft" clipping. I've not heard any comments as to performance at levels which do not over drive the amp, so I don't know what difference to expect there, if any. I expect that the biggest difference between "hard" and "soft" clipping is the presence or absence of higher-ordered harmonics of the program material, and higher-ordered components are what make the music harsh. MOS and Junction FETs exhibit characteristics that are similar to tubes, so you might expect that amps deisgned with FETs will show similar "soft" degradation. Otherwise, I expect that the only difference you could detect would depend on your own audio acuity, experience, and the various types of equipment you buy. (i.e. - there is little detectable difference between components that are carefully designed, and correctly used in the first place.) -- Mike Wincn ncpjmw@brahms.AMD.COM (408) 749-3156 DISCLAIMER: I speak for myself unless noted otherwise.