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[#15] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
My engineering knowledge is limited as that's not my profession. But I would think if you change from 50Hz to 60Hz, the energy transfer is the same, except the "iron loss" will be more. To the best of my knowledge, my middle school teacher taught me there is "copper loss" and "iron loss" for a transformer. Copper loss is due to copper wire resistance. And iron loss is due to eddy current and vibration. Bad core material will have much eddy current loss and the transformer will get hot. But since we are only talking about 50Hz to 60Hz, effect shouldn't be too high, as we are not saying 50Hz to 1Khz. Otherwise we will all have problems when bringing US equipment back to Hong Kong...:-)
yukclee
個人訊息 會員
219.xxx.xxx.34
2008-09-23 16:58
[#16] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
most of tansformer factory quote the spec. of it transformer also specify 50/60Hz primary winding, whatever the capacity from 15 to 1000VA.
http://docs-asia.electrocomponents.com/webdocs/0111/0900766b80111b4e.pdf
epic
個人訊息 正式會員
210.xxx.xxx.118
2008-09-23 17:12
[#17] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
Interesting discussion!

Now, as you guys may know, the older PS Audio powerplants allow users to raise the AC frequency up to 120Hz (or so). While PS Audio claimed that this would charge the power capacitors better, what would 120Hz AC do to the power transformer of a power amp.?

thekong
個人訊息 會員
202.xxx.xxx.81
2008-09-23 18:00
[#18] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
Thekong hing,

Good example and question, I never tried the 50Hz or 60Hz TX worked under 120Hz environment, but for me, my answer is positive but not too much gain to use high frequency for the transformer from the electrical side.

Power - from ’hetzer hing’ you get higher VA value, but due to the size of the wire still remain unchanged so you can’t get much higher

Power Loss - from “yukclee hing” Copper loss still remain unchanged but you will get higher Eddy-current loss and Hysteresis loss. They also will generate more heat, but if the grade of the iron core is high such as same material of output Tx applied, those two losses will be minimized to a very low value.

But the other side is after rectifier, you can imagine the time interval in between P to P is shorten that means you got better DC source if your cap good enough, once you got better DC source I suppose you got better sound for the same condition.

Hope some brother tried before and let us know the result.
et2
個人訊息 會員
203.xxx.xxx.63
2008-09-23 19:38
[#19] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
首先,我相信在一般的 application 內,並不雖理會 50/60 Hz 對 equipments的兼容性,很多的牛廠都說明它們的牛能正常工作在 50 or 60 Hz的。很難找到一隻牛只能工作在50 or 60Hz的,應沒有廠家做這樣的牛吧!從發燒角度看,50 , 60 , 120 Hz 的 AC supply是對聱音有影響的。120Hz 我沒試過,我只試過用 on-line UPS 轉做 60Hz,但出來郊果我不喜歡,當然,這並不能代表 60Hz 不好,相信是 UPS 的問題!所以如一定要用60Hz 去operate 你的 equipments, 你所花費在 converter 的金錢也不小。
epic
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221.xxx.xxx.84
2008-09-23 20:07
[#20] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
"""50Hz or 60Hz TX worked under 120Hz environment,"""


Would this be similar to using 3 phase electricity to power 2 phase equipments?
The result is that you would have smaller ripples after rectification. Theorectically this should be DC of better quality and therefore less demanding in respect to reservoir capacitors (as PS Audio claims).

thomasc2
個人訊息 會員
218.xxx.xxx.151
2008-09-23 21:32
[#21] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
謝謝各師兄, thx!
hkf112233
個人訊息 會員
61.xxx.xxx.70
2008-09-23 22:06
[#22] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
"Theorectically this should be DC of better quality and therefore less demanding in respect to reservoir capacitors (as PS Audio claims)."

Yes, I think so the power should be more stable due to the above reason. Power is too important for HiFi system.
et2
個人訊息 會員
124.xxx.xxx.35
2008-09-23 22:49
[#23] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
I think it should be 400Hz instead of 120Hz. 400Hz is US mil. spec. for some of their voltage supply. That's why if you buy a 變器, a lot of times they have 400Hz AC output.
Some of the late hifi equipment such as the later ML32 preamp do re-generate their power to 400Hz first before they rectify to DC. I have not follow on why it is better (perhaps Mark Levinson website have some technical paper to explain) but perhaps better for cap. charging and diode switching?? And you will have more pure DC without some switching higher freq. harmonics...dunno..
yukclee
個人訊息 會員
218.xxx.xxx.42
2008-09-24 12:28
[#24] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
In using the UPS to change the power supply to 60Hz is nothing wrong. But then most of the UPS do not put much attention on choice of components, material, layout, shielding, etc. to make it a hifi equipment. Hifi equipment has gone a long long way to iron all these things to make them of very high quality for us to enjoy. Just putting a normal class UPS will just downgrade the whole chain.
A hifi class UPS should have a full copper chassis and internal shielding. Audio grade caps, soft recovery diodes, OCC copper bars and wires, etc...!
yukclee
個人訊息 會員
218.xxx.xxx.42
2008-09-24 12:38
[#25] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
#11

Will it adversely affect sound quality?
aheung
個人訊息 會員
219.xxx.xxx.6
2018-08-31 12:31
[#26] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
60 hz 唔雖要理會
--------------------------
Now I use CSE transformer (200V => 100V) and E-100 for my Marantz Project D1, the E-100 can provide electronic power at either 50Hz or 60Hz.

Using 50Hz or 60Hz causes no problem to equipment, but makes difference to my ears.

Happy listening !

最後修改時間: 2018-08-31 13:40:07
waterman
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61.xxx.xxx.139
2018-08-31 13:38
[#27] 有冇師兄知有冇變壓器由220v/50hz轉120v/60hz,    
ups are powerline polluters unless it is equipped with high quality harmonic filters. You may say who cares about my neighbour's hifi as long as my hifi system sound good.
hotiron
個人訊息 會員
49.xxx.xxx.74
2018-08-31 13:56
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