So nice....


下一步嘅你可以 嘗試令這個SUT 內部, 做一些防幹擾的行為

有效的, 明顯聽得出事前 事後 嘅結果

Have fun


有一啲音樂 do need active Mc pre pre


最後修改時間: 2024-04-29 18:33:46

參考師兄同網上資料，我先將SUT ground 用wire 駁去
phonostage ground, 大部分hum 冇咗
跟住我再將tonearm 條ground駁埋去SUT hum 又细咗
依家只剩下微量hum要好埋先聽到，往後先再研究下點改善
在此又感謝各師兄前輩的寶貴意見

**用外置MC牛啲聲真係好好多

Mc tranformer 其實有at least 四個部分

Such as

input side

Output side

Insulation

Shielding cage..

你的問題 有少少不夠仔細

簡單而言 你敘述的情況 is having hum or those so called ground loop and it is from the SUT

不是完全簡單的

但係逐步逐步去試做錯又唔會有傷害的, 花的時間都係十幾分鐘

很快會 移除 those hum

First step, u can connect your cartridge input ground point to phono stage chassis ground
希望就可以解決最顯著嘅hum noise ( guess 仲有微量 淨返嘅.. Let's see later)


最後修改時間: 2024-04-28 20:52:59

其實係咪應該有條線由MC transformer 去chassis ground

試下喺唱盤金屬部分搭條地線去前級 機殼金屬部分, or the phono stage 電源接地的充電地方試一試?

唱盤的金屬部分 etc 和arm唱頭的組件有冇 在地線連接起來?

現在的問題希望可以在十分鐘內解決

亦可能將要面對更多的有趣問題

最後修改時間: 2024-04-27 20:29:33

依家每逢開Turntable 供電啲Hum就出現，隨volume 增加/減少，off 咗Turntable hum 就消失

MM phono 開(沒連接MC SUT)， Preamp 開， power amp 開
冇hum

Turntable 個地係接MC SUT 個ground

排好位，度掂D線點行，盡量短而直接，有長就剪咗佢!

我有2朋友都做過這個diy kit

他們說他們都花了一段時間去解決這些噪音問題


Any photo? Seem fun

得到各師兄指點，SUT已順利出聲

不過好多noise, hum

可能機殼太細，啲線交錯互叠、2個牛太近…..

#10,

suggest you stick to original wirings for better shielding. if you decide to disconnect the chassis from input/output grounds, please take care of the blue & black wires as well (and, also the load resistor if any).




最後修改時間: 2024-04-24 17:46:58

I made similar...

I have a ground lift from input to output, some time.. Not sure why, not yet try to understand why.. With some table and some cartridge.
It has excess hum.. Then I remove this link (input to output ground link) for that combination

感謝師兄們指導

最後請教重有冇需要用條線 連接input 同 output ground 落chassis ground?

唔該晒吖

最後修改時間: 2024-04-24 11:52:47

based on the diagrams in #1&7, the color scheme of your SUT leads should be like this .....



To complete the wirings, the upper 2 pins of the switch should be shorted as shown below (circled in pink)



Of course, you can bypass the switch and connect your SUT at a fixed ratio of 10x or 20x

10X ratio:
- connect Red & Green wires together
- Brown wire connected to Input Live
- Black wire connected to Input GND

20X ratio;
- connect Red & Brown wires together at Input Live
- connect Green & Black wires together at Input GND




最後修改時間: 2024-04-24 09:46:13

除咗係放大率之外

1:10 if the mm stage is (usually) 47kohm, the Mc is loading at about 470ohm

At 1:20 the loading is about 117ohm


Is about matching too

Is good to have that option

And u can play. Around the loading resistance value too



最後修改時間: 2024-04-24 05:21:11

呢個官方接駁圖，不過係有1:10 or 1:20 放大選擇製

我係想fix 1:10

Blue 同 Yellow 度個Ohm 值又上又落，又上又落 （0.xx 至4.xx)

之前唔同顏色wires 逐pair 去測個電阻值

如相中

分到初次級，仲有相位未知，問返賣呢件野俾您個位，叫佢提供份規格書，唔使靠估

You can diy and going to diy = 你應該有個他錶,

Use the ohm meter to check

應該幾分鐘內你就會搵到你要嘅答案

2nd 這兩條線度出嚟當然係高 a lot VS Pri

PRI 四條線有兩組, each pair 應該係差不多的ohm

之後你可能還有其他疑問的


Good luck

加相

Manual 有 Red, Pink
MC牛有 Brown 同 White

其他顏色大家都有