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.

MID phone

MID phone all special parts.

x86 PC part PCB Top and bottom views.
CPU VIA C7M Nano 500MHz and Vx875 chip set.
DDRII 512M.

Smart phone PCB Top view.

ID outline view 1.

ID outline view 2.

Platform under develop in Windows mode and verify Keyboard driver.

Platform under develop in Graphic mode and tuning display location.

Platform under develop in BIOS text mode.

After check window mode then waiting to confirm rotate display driver.

Display debug flow in two operation system because display is phone type LCD module.

Platform under kernel booting test and successful into  Android operation system.
Just waiting modify power on sequence.

Original Android small GUI.

Migration to big GUI.
Into SmartPhone Android system.

Switching into Windows operation system just one key.

Either could turn-off each system any time.

Toy12 Plasma tweeter Diy-9 Check sound color

Plasma Tweeter xover High-Pass filter >7Khz.
Benchmark Jensen Tweeter RP-302 7Khz~10Khz


Left side tub is ECL82 and right side is 6C45π.
ECL82 三極管 Triode 是調變器modulation , 五極管 Pentode 是調變Level control.


德國TFK 德律風根 ECL82,  音像較淺 audio shallow ,  7Khz~10Khz 較凸出 Vigorous tone,10Khz~15Khz Level  響應就弱 response week, 音色渾厚 ,最像 just like Jensen Rp-302 performance.


德國VALVO ECL82  audio shallow 音像較淺, 7Khz~10Khz 較凸出,音色線條清楚些 soind clear line ,10Khz~15Khz Level  response week 響應就弱.


蘇聯 Svetlana ECL82 (6Φ3π)   7Khz~15Khz 響應平合 response normal ,但音色線條清瘦 ,空洞, 音色偏冷 sound  clear line , cool & thin.


德國LORENZ ECL82 在Plasma tweeter modulation 應用較適合 7Khz~15Khz 響應較佳 response pretty good ,音像較深, 音色線條清楚 sound filed of the deep carved .


德國SIEMENSECL82   7Khz~15Khz 響應較佳 response pretty good ,音像刻化較深, 音色線條深刻化清楚, 且深動自然.sound filed of the deep carved  and sound natural.



OTK 6C45Π 大鈴鐺, 音像最淺 audio shallow ,  7Khz~10Khz 較凸出,10Khz~15Khz Level  響應就弱 response week ,
音色渾厚. 較 Jensen Rp-302 表現弱 more week than Jensen.



Sovtek 6C45Π 7Khz~15Khz 響應平合,音色線條清瘦 , 音色偏冷 sound  clear line , cool & thin.

EH 6C45Π ,7Khz~15Khz 響應較佳 response pretty good  ,音像刻化較深, 音色線條深刻化清楚, 自然.

sound filed of the deep carved  and sound natural.

BMS Charge and Dis-charge Autotesting system

Cell module Charge ,Dis-charge Autotesting system.
In dis-charge mode Cascade 2 module to 48V usage 1A to dis-charge meanwhile continue monitor voltage.
Do Low voltage protection and record parameter.



In Charge mode monitor each cell charge voltage.

fully cells of charge and discharge  autotesting.