F6 Amplifier

They make some really nice distortion free amps over in SS forum, containing 200 transitors, OLG of 4 million, DF of 800. Funny thing is, while people have hard time paying 20$ for best available Jfets like R100 and their possible uber low distortion, numerous folks are regularly paying hundreds of dollars for those distorted glow plug thingies. Perhaps evryone who likes tubes is simply suffering from Nostalgia. Like it or not, low distortion is not the complete answer and graphs don't play music, they simply helps us understand whats going on. If i were to put a "wannabe SiT" switch on the front, it seems logical to have it set for 2-3 settings. Any more and you are getting into diminishing returns. What I am talking about. I passed diminishing returns in audio October of last year.
 
Trying to get there. Still got this prooving somrthing bug I gotta grow out of. Stupid kid. Here is THD spectrum of 6V6 Pre. B1 is clean and neutral. THis thing of course adds something. I like both. Its like picking vanilla or chocolate.
 

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They make some really nice distortion free amps over in SS forum, containing 200 transitors, OLG of 4 million, DF of 800. Funny thing is, while people have hard time paying 20$ for best available Jfets like R100 and their possible uber low distortion, numerous folks are regularly paying hundreds of dollars for those distorted glow plug thingies. Perhaps evryone who likes tubes is simply suffering from Nostalgia. Like it or not, low distortion is not the complete answer and graphs don't play music, they simply helps us understand whats going on. If i were to put a "wannabe SiT" switch on the front, it seems logical to have it set for 2-3 settings. Any more and you are getting into diminishing returns. What I am talking about. I passed diminishing returns in audio October of last year.
In post#374, Mr. Pass responded to lhquam saying that he is not trying to go below 0.1% THD.
 
Try 60,000 tubes!

IBM AN/FSQ-7
IBM-SAGE-computer

Technical Description
Size: CPU (50 x 150 feet, each); consoles area (25 x 50 feet) (total system=20,000 square feet)
Weight: 250 tons (500,000 lbs)
Architecture: duplex CPU, no interrupts, 4 index registers, Real Time Clock
Word Length: 32 bits
Memory: magnetic core (4 x 64K word); Magnetic Drum (150K word); 4 IBM Model 729 Magnetic Tape Drives (~100K words ea.); all systems with parity checking
Memory Cycle Time: 6us
I/O: CRT display, keyboard, light gun, realtime serial data (teletype, 1300 bps modem, voice line)
Performance: 75KIPS (single-address)
Technology: vacuum tubes (60,000); diodes (175,000); transistors (13,000)
Power Consumption: about 3 Megawatts


 

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be my guest :clown:

I just couldn't resist ........ :rofl:


Got Turkish coffee for this guest; semi-sweet pls? Back to IGBT. It expands the universal scope of Conceptual F6, and more importantly may simplify its assembly because of the integration of multiple IGBTs in one package.
  • IGBT has the high input resistance of MOSFET [no DC through transformer] and the high transconductance of BJT which may give a higher OLG [and benefits or ills ] than attained with JFET.
  • The attached file shows the diagrams of packaged IGBTs [K, L, M] from a catalog of International Rectifier. Package M has the output stage of a clone of Conceptual F6. Most probably this pair has matched characteristics if cut from the same fabrication die. Packages K and L have multiple IGBT pairs.
Rush is interested in using MOSFETs in his clone of F6. This file also shows packages with multiples of MOSFETs which may have matched characteristics.
 

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