ToyX project EQ Linearizer study ....Add Output transformer

Attach modify schematic drawing.
Fix impedance for better audio matching.

Modify R channel wire connection and add OTP.


Modify L channel wire connection and add OTP.



First time just modify one channel and after A-B test decide to replace two channel together.
響應較佳 ,音像刻化, 音場,音色線條深刻都有更進一步, 自然.

Toy12 Plasma tweeter 離子高音 Diy-10 RF power amplifier PL519 check sound color

PL519 Power amplifier for plasma tweeter RF radiation and Heater  40V.



Under testing picture and test plasma radiation.
Modify PL519  plate current about 150mA for A,B test.


德國 VALVO PL519    音場淺且後場有些交代不清,音像較凸出, 音色較厚些且硬一點. 
PL519 plate current over 220mA tuning to 150mA.


德國 SIEMENS PL519   7Khz~15Khz 響應較佳 ,音像刻化較深, 音場深,音色線條深刻化清楚, 且深動自然.
PL519 plate current over 200mA tuning to 150mA.


法國 MAZDA PL519  音場刻化較深, 但音色線條清瘦 ,空洞, 音色偏冷.
PL519 plate current about 150mA.

Pasted visit detail  .... from Acapella boss Herman Winters
...離子高音
Acapella另一項特點就是離子高音（ION Tweeter），所謂離子高音是利用真空管昇壓放電產生電離發聲，由於沒有振膜，所以質量為零，高頻發聲完全沒有延遲，是非常理想的高音（或稱超高音）設計。雖然離子高音的設計原理近乎完美，可是怎麼沒有大量應用？道理不難理解：太貴了。Winters說Acapella的離子高音以西門子 PL519真空管震盪，裡面還有石英管做阻尼，大部分玩家都知道真空管有壽命，時間到了之帶該換，但可能很多人不知道，這根石英管也有壽命，使用年限大約十年，時間到了應該更換，以國內銷售Acapella的歷史來看，可能有些發燒友自家的離子高音應該換石英管了，如果有需求不妨與代理商洽詢，尋求正廠零件更新。
...after test some concept come out
1.There design audio system concern harmonic distortion of amplifier.
2.There concern components affect sound color.
So there choice SIEMENS PL519 too.

My final system combination is 5U4g+EH 6C45Π+SIEMENS ECL82+SIEMENS PL519.

Toy13 300B Amplifier DIY Record....2

Insist 6C45Pi and 300B is AC heater.
Finish signal tube B+ voltage connect and 300B cathode voltage setup.


Finish signal tube B+ connect and finish coupled 300B grid C-R connection.


Finish stand alone high voltage power.

Pretest whole 300B amplifier.

Toy13 300B Amplifier DIY Record....1

Design & drawing 300B high voltage  circuit with delay on function.
Main power switch setup in 300B case.
High voltage will be remote turn-on and through Jump wire supply to 300B case.


Design & drawing 300b signal amplifier & 300B bias circuit.
Calculate 6C45pi & 300B plate voltage.


Prepare all components  & 300B tubs.


Do placement & hand drill hole for Mount 5U4G & delay on Relay.
High voltage & chock transformer will mount on this box too and  separate circuit with 300B case.


Do placement & hand drill hole for mount 6C45Pi & 300B platform.
6C45Pi & 300B  high voltage & bias circuit will fix in the case.



Mount 6C45Pi & 300B platform structure picture.

Toy3 D/A couple capacitor of Balance output estimate -2 more cap. & different value

D/A couple  capacitor of Balance output estimate -2 more cap. & different value


Unknown PP couple capacitor.
Audio shallow, Sounds too rough.


Bennic PP couple capacitor.
Sounds not rich.


Old CDET 2.2uf/200v  PP couple capacitor
Clear body line sound cool & thin.
.

New CDET 5uF/100V PP couple capacitor.
Clear body line sound better than before.


ROE 10uf/68V pole couple capacitor
Clear body line sound got a little lite mean sound density not enough.



ERO 4.7uf/100V PP couple capacitor
More sound detail ,sound density enough but Low frequency responce not good feel empty.


ERO 6.8uf/100V PP couple capacitor
More sound detail ,sound density enough Low frequency responce  feel better now.


ERO 10uf/250vV PP couple capacitor.
Better response ,sound field of the deep carved ,Low freq. got vigorous tone.
All benchmark base on WM8741+PWM Filter OP AD827AQ+ Differential combiner OP AD797AN.
Sonic Frontiers Corp. have a research paper mention one type D/A usage same value 10uf cap. is better too .
For your reference.

Toy11 VT4C 211AMP -5 ..... verify 211 AC heater capacitors sound color

I like sound of AC heater for VT4C so I do some circuit modify as drawing.
Old connect as below and no 62ohm/50W resistors & no capacitors shunt to GND.


Original connection picture.
No resistors & capacitors. Sound not good and too rough.


Connect  capacitors & mount resistors on water cooling heat sink.


Sounder 10uf/250V sound have clear line,sound not rich, rough and nothing special.
VT4c cathod RIFA capacitor sound color feel not good and change into Spraque 100uf/150V.


CDE 8uf/400V 音色較渾厚 Vigorous tone,音像較淺 audio shallow ,低頻轟轟,悶悶的打不出線條聲音 Low-freq humming.


Old CDE 4uf/200V  低頻聲音線條較清楚有形體 Low freq. have clear body line ,但音色線條清楚偏冷,清瘦 but clear line sound cool & thin.


ERO 4.7uf/250V 響應較佳 better response ,音像(音場)刻化較深 sound filed of the deep carved , 音色線條深刻化清楚, 沒啥毛邊,低頻聲音較有梗的清楚形體 Low freq. have clear body line ,較自然,是以布懸邊為參考.因較不喜歡rubber懸邊低音聲底,軟軟的低音轟聲.

GE-211 plat voltage .

300B tubes

Just receive 300b tubes shipping from China.


曙光白底座茄子型.


300B testing specification.
Plate current 45mA.


Old 曙光 300B-98 close view.



曙光白底座茄子型 300B close view.