Elekit-TU8600R-pwr-电气原理图手册

300B SE Tube Amplifier Kit TU-8600RLimited production model *ATTENTION!TUBES NOT INCLUDED!TU-8600,a 300B single-ended tube amp kit released as a limited production model for 2017ran out so quickly that we received many requests for reproduction from both domestic andoversea markets.Upon such request,we reproduced TU-8600 as a revised version TU-8600Rthis September,with minimal modification from TU-8600.Limited production,without tubes.Power circuit enhancementA high efficiency,low magnetic flux leakage R-core is used.The rectifierconsists of schottky barrier diodes that require shorter recovery time.This results in a reduction in even negligible noise spikes.The windings of the power transformer include individual windings for thefilament heater(A Power),high voltage (B-power),and bias to stabilize theNegative Feedback (NFB)circuitry(C-Power).In addition,all power is stabilized to reduce residual noise as much aspossible.This results in the noise level as low as less than 1/10 of that ofTU-8300RStable NFB circuit for great audio qualityTo make the most of the 300B tubes,the characteristics of various parts andcircuits,including OPT have been improved.The NFB is applied to thecathode of the 300B by the third winding of the OPT as well as to the voltageamplifying stage.Consequently,the overall NFB is minimized as well as thechance for the transient response.New active automatic bias adjustment systemFor the 300B tube bias,the power supply is equipped separately,and a"New active automatic bias"is used where the amp detects plate currentand automatically adjust the grid voltage.This design earns TU-8600R thepriviledges of both selfbias and fixed bias.In addition,current detectingcircuit is moved from the cathode side to the Bpower side resulting ineven better sound quality.Driving 300B tubes to full power万.6A very orthodox design is used for the voltage amplifying stage tobring out the outstanding characteristics of the famed 300B tubes.Ofspecial note is that 12AU7(ECC82)is used in parallel for the 2nd stageto drive the 300B tubes to full power-resulting in 200Vp-p withoutWith the tube eoverclipping.Tube-friendly designWarm-up time for directlyheated and indirectly-heated tubes largely differIn most designs,amp power-up starts heating both the directly heated 300BAtsAtubes (fast warm-up)as well as the indirectly-heated 12AU7 and 12AX7(slower warm-up).In TU-8600R,the 300B tubes are heated after theindirectly-heated tubes have warmed up.A very tube-friendly design thatwill not overload tubes that have not fully warmed up.Ample space for larger coupling capacitorsCapacitors can have a big effect on sound.TU-8600R uese highquality conductive polymer hybrid electrolytic caps andpolypropylene film caps.For those who wish to use other higherquality caps,there is ample space provided on the PCB for mountinglarger caps.Output level selection for headphonesFor the headphone,you have 4 selections of output level to matchyour headphone.Safety tube cover included