xtreme4099
Headphoneus Supremus
- Joined
- Apr 10, 2003
- Posts
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On Behalf of PPL im posting this for the DIY Community (phil doesnt like dealing with linking and hosting stuff so i pitched in for him)
From Phil :
Hello Folks, over the past year or so I have been slowly developing my tube Amp. I heavily investigated several different topologies and after a lot of digging I found something that suits my personality and something I can build upon.
The Legendary sounding 6BQ5/EL84 Output tubes are operated in push pull but unlike conventional push pull, a phase inverter is not used, as the output stage uses a unique method of driving the push pull output transformer. This method was first popularized by Melvin Leibowitz, Electronics World, June 1961 in the 6 Watt Compact Hi-Fi Amplifier
http://www.triodeel.com/compact.html
The Leibowitz circuit results in only one DC blocking Capacitor in the entire signal path and for this an Audiophile Film type of sufficient capacity to afford extended Bass response is specified in Phil’s Design. The elimination of the typical phase inverter stage removes an entire active circuit from the signal path yet still retails all the qualities of the more conventional Tube design. Our technique naturally uses the output tubes to do what normally requires an additional stage. This topology is now known as the self split configuration. This design has natural inherent balance and thus flow with Phil’s natural design concepts of operating the device under conditions most natural to the devices employed in the circuit. The Self split output stage topology operates the output tubes naturally out of phase and thus dispensing with one entire tube from the signal path while gaining improvements in symmetry as opposed to a poorly implemented phase inverter stage.
The Leibowitz circuit also popularized a now legendary small output Tube the highly praised EL84 or 6BQ5 for Americans. This tube has been extensively used in highly sought after Fender Guitar amplifiers in addition to Classic Audiophile Amplifiers of the Tube the Classic Marantz Model 5 is but one of many Audiophile applications of the EL84/6BQ5 Output tube. This topology with large value power supply capacitors and individual bypassing and filtration for each section and you has a tube amplifier of extremely good technical performance. I believe this Amp is a true work of valve artistic design and Musicality, featuring the punch and dynamics of pentode operation or the more detailed and refined Triode mode. The Output tubes screen grids are heavily bypassed and filtered with RC techniques employing large reservoir capacitors to aid stability and provide a blacker background.
Shown below are the schematic and PCB parts location at the present stage of development. This is intended to be a paint by numbers Tube amp so that the novice as well as the Tube o phile can easily assemble this. I inquired to some of my prior project Team members about doing this up al La PPA style. So rather that let my gift to the DIY Community. I am posting as an interest check to first off see if there is any interest. Then see what can be done about boards may be a group by or something, I don’t want to be involved in setting that up I leave it all up to someone else.
From Phil :
Hello Folks, over the past year or so I have been slowly developing my tube Amp. I heavily investigated several different topologies and after a lot of digging I found something that suits my personality and something I can build upon.
The Legendary sounding 6BQ5/EL84 Output tubes are operated in push pull but unlike conventional push pull, a phase inverter is not used, as the output stage uses a unique method of driving the push pull output transformer. This method was first popularized by Melvin Leibowitz, Electronics World, June 1961 in the 6 Watt Compact Hi-Fi Amplifier
http://www.triodeel.com/compact.html
The Leibowitz circuit results in only one DC blocking Capacitor in the entire signal path and for this an Audiophile Film type of sufficient capacity to afford extended Bass response is specified in Phil’s Design. The elimination of the typical phase inverter stage removes an entire active circuit from the signal path yet still retails all the qualities of the more conventional Tube design. Our technique naturally uses the output tubes to do what normally requires an additional stage. This topology is now known as the self split configuration. This design has natural inherent balance and thus flow with Phil’s natural design concepts of operating the device under conditions most natural to the devices employed in the circuit. The Self split output stage topology operates the output tubes naturally out of phase and thus dispensing with one entire tube from the signal path while gaining improvements in symmetry as opposed to a poorly implemented phase inverter stage.
The Leibowitz circuit also popularized a now legendary small output Tube the highly praised EL84 or 6BQ5 for Americans. This tube has been extensively used in highly sought after Fender Guitar amplifiers in addition to Classic Audiophile Amplifiers of the Tube the Classic Marantz Model 5 is but one of many Audiophile applications of the EL84/6BQ5 Output tube. This topology with large value power supply capacitors and individual bypassing and filtration for each section and you has a tube amplifier of extremely good technical performance. I believe this Amp is a true work of valve artistic design and Musicality, featuring the punch and dynamics of pentode operation or the more detailed and refined Triode mode. The Output tubes screen grids are heavily bypassed and filtered with RC techniques employing large reservoir capacitors to aid stability and provide a blacker background.
Shown below are the schematic and PCB parts location at the present stage of development. This is intended to be a paint by numbers Tube amp so that the novice as well as the Tube o phile can easily assemble this. I inquired to some of my prior project Team members about doing this up al La PPA style. So rather that let my gift to the DIY Community. I am posting as an interest check to first off see if there is any interest. Then see what can be done about boards may be a group by or something, I don’t want to be involved in setting that up I leave it all up to someone else.
