"Vacuum Tube Current Sink Drive"
Hello,
I was just wondering if anybody has herd of this type of a design of amplifier circuitry before? I am new to the DIY seen and I'm learning alot (slowly), but the important part is I'm having FUN! So if anyone could shed some light on this or tell me if it is "SNAKE OIL"!
Here is the info about it and a link to a picture of the internals.
"Our Vacuum Tube amplifiers are the first to incorporate U.S.Amps proprietary "VTCSD" (Vacuum Tube Current Sink Drive) output circuitry. VTCSD "follows" the high voltage tube signal STRAIGHT INTO THE SPEAKERS, adding only current in a form of "amplifier power steering" - free from voltage gain or negative amplifier feedback! Vacuum tubes are renowned for their high dynamic range and smooth emphasis of even-order harmonics. The transformer-less VTCSD circuit brings out hidden qualities of the vacuum tubes, including excellent frequency response, smooth "clipping" and high signal-to-noise ratios. VTCSD divides audio signal amplification in two separate areas, voltage and current. By starting with the vacuum tube as a source of high voltage (vacuum tubes operate at four times the voltage of transistors) VTCSD adds a second solid-state "amperage amplifier". The "amperage amplifier" is a null-gain circuit driven by "current syncs" that mirror the voltage signal and provide "torque" to the speakers in perfect synchronization with the voltage content, that neither distorts or colors the original tube sound! The results are astonishing. All of the intensity, transience, and frequency response of the vacuum tube, which can operate at MUCH higher output voltages than audio transistors. TU-4360 Conventional amplifiers use the same component(s) to amplify voltage and current from a "line" or preamp level to an audible "speaker" level. This includes the introduction of part of the signal slightly out of "time alignment" for the purpose of retarding high frequency response, thus stabilizing the overall circuit. These "Negative Feedback" loops can be local (contained to one critical part of the circuit), or global (pertaining to the audio output as a whole). The introduction of negative feedback is detrimental to sound quality as it introduces a certain "harshness" into the character of the sound. This is particularly true in fast-switching transistor circuits that already contend with the emphases of odd-order harmonics that are a product of their design. Tube circuits generally fare somewhat better in the presence of negative feedback. The higher voltage and slower operating speed of a tube naturally emphasizes pleasing even-order harmonics. Traditional tube amplifiers produce high voltage which is excellent for transience, attack, transparency, and staging, but are severely limited by the amount of current available to drive speakers. The final stage of a traditional tube amplifier is an "output transformer" which transforms some of the voltage energy into current. The resultant signal is better suited to drive an audio loudspeaker, but a great deal of the original tube dynamics and frequency response are lost forever. With our VTCSD (Vacuum Tube Current Sync Drive) input signal is fed DIRECTLY into the tube. There are no solid state gain stages or processors in the signal path. The original high voltage tube signal is joined by a null-gain current "following" circuit that is pulled to the voltage rails by an opposing pair of "current syncs", providing a sort of "amplifier power steering" to deliver speaker-driving power without taxing the character of the original tube voltage content. TU-4360 Four Channel Class A Amplifier Direct Tube Input Oversized MOSFET Power Supply Total Power Output: 360 Watts RMS THD at Rated Power: <0.05% Signal/Noise Ratio: >100dBA Frequency Response: 15Hz-50KHz +/-0dB Fuse Rating: 40 Amps Dimensions: (Including Terminals) 62mm / 2.44in High 229mm / 9.0in Wide 368mm / 14.50in Long Weight: 3.63kg / 8.00lb Two Ohm Stable 75 Watts x 4 into 4 Ohms 90 Watts x 4 into 2 Ohms"
Link (picture) http://www.usamps.com/products/inv/tu-4360_bottom_01.jpg
Hello,
I was just wondering if anybody has herd of this type of a design of amplifier circuitry before? I am new to the DIY seen and I'm learning alot (slowly), but the important part is I'm having FUN! So if anyone could shed some light on this or tell me if it is "SNAKE OIL"!
Here is the info about it and a link to a picture of the internals.
"Our Vacuum Tube amplifiers are the first to incorporate U.S.Amps proprietary "VTCSD" (Vacuum Tube Current Sink Drive) output circuitry. VTCSD "follows" the high voltage tube signal STRAIGHT INTO THE SPEAKERS, adding only current in a form of "amplifier power steering" - free from voltage gain or negative amplifier feedback! Vacuum tubes are renowned for their high dynamic range and smooth emphasis of even-order harmonics. The transformer-less VTCSD circuit brings out hidden qualities of the vacuum tubes, including excellent frequency response, smooth "clipping" and high signal-to-noise ratios. VTCSD divides audio signal amplification in two separate areas, voltage and current. By starting with the vacuum tube as a source of high voltage (vacuum tubes operate at four times the voltage of transistors) VTCSD adds a second solid-state "amperage amplifier". The "amperage amplifier" is a null-gain circuit driven by "current syncs" that mirror the voltage signal and provide "torque" to the speakers in perfect synchronization with the voltage content, that neither distorts or colors the original tube sound! The results are astonishing. All of the intensity, transience, and frequency response of the vacuum tube, which can operate at MUCH higher output voltages than audio transistors. TU-4360 Conventional amplifiers use the same component(s) to amplify voltage and current from a "line" or preamp level to an audible "speaker" level. This includes the introduction of part of the signal slightly out of "time alignment" for the purpose of retarding high frequency response, thus stabilizing the overall circuit. These "Negative Feedback" loops can be local (contained to one critical part of the circuit), or global (pertaining to the audio output as a whole). The introduction of negative feedback is detrimental to sound quality as it introduces a certain "harshness" into the character of the sound. This is particularly true in fast-switching transistor circuits that already contend with the emphases of odd-order harmonics that are a product of their design. Tube circuits generally fare somewhat better in the presence of negative feedback. The higher voltage and slower operating speed of a tube naturally emphasizes pleasing even-order harmonics. Traditional tube amplifiers produce high voltage which is excellent for transience, attack, transparency, and staging, but are severely limited by the amount of current available to drive speakers. The final stage of a traditional tube amplifier is an "output transformer" which transforms some of the voltage energy into current. The resultant signal is better suited to drive an audio loudspeaker, but a great deal of the original tube dynamics and frequency response are lost forever. With our VTCSD (Vacuum Tube Current Sync Drive) input signal is fed DIRECTLY into the tube. There are no solid state gain stages or processors in the signal path. The original high voltage tube signal is joined by a null-gain current "following" circuit that is pulled to the voltage rails by an opposing pair of "current syncs", providing a sort of "amplifier power steering" to deliver speaker-driving power without taxing the character of the original tube voltage content. TU-4360 Four Channel Class A Amplifier Direct Tube Input Oversized MOSFET Power Supply Total Power Output: 360 Watts RMS THD at Rated Power: <0.05% Signal/Noise Ratio: >100dBA Frequency Response: 15Hz-50KHz +/-0dB Fuse Rating: 40 Amps Dimensions: (Including Terminals) 62mm / 2.44in High 229mm / 9.0in Wide 368mm / 14.50in Long Weight: 3.63kg / 8.00lb Two Ohm Stable 75 Watts x 4 into 4 Ohms 90 Watts x 4 into 2 Ohms"
Link (picture) http://www.usamps.com/products/inv/tu-4360_bottom_01.jpg
Just from this description, it's difficult to say what they've got beyond hype. This COULD describe the well-known topology of a tube voltage amp driving a transistor (BJT or MOSFET) follower. Or it could describe something else. Strip away the analogies and Carver-like puff, and you've got about two sentences of substantive description.
Co_Driver said:
I'll suggest this is a cheap Chinese-made amp with cheap Chinese made valves to appeal to the gimmick / gadget in-car audio crowd . In other words an SRPP/mu input stage with a nasty class B output stage , same thing but more expensive than something without valves , built to a price but hyping with gimmicks to increase the sale value . Any 'improvement' by using valves would surely be offset by vibration-induced microphony would it not ?
316a
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