China made tube amp

Dear Forumer,

Is it safe using a China made tube amp with input 220v in Malaysia ? Would it burn the transformer due to our voltage is 240v ? Any suggestions ?

yes can use. i dont think it will burn the transformer.. usually 220-240v can be use interchangeably. but not 110v, u will blow the equipment

Buy a power regulator that stabilize power to a contast 220V from unstable 220V-250V .

Jalan Pasar has plenty of it. In addition you'll hear better sound coming out from your amp

what if its 230v?

+/- 10% should be fine on mains voltage should be fine, unless the makes really pushes the limit of the tubes.

- br@d - wrote:Buy a power regulator that stabilize power to a contast 220V from unstable 220V-250V .

Jalan Pasar has plenty of it. In addition you'll hear better sound coming out from your amp

By adding those AVR, I think will down grade the sound. Isn't it ?

Opera,
AVR, i believe its suppose to improve the sound by regulating the voltage. How can this downgrade the sound? Isn't a stable voltage better?

luxman,

I'm also not sure...but heard some SIFU said it will down grade the sound. They recommend to get the isolation transformer. really no idea about this. not familiar with electrical.

Opera,

I am using it for my TV and it did improve visually. As for audio, i did not detect any degrade in sound when used with my preamp and cdp.

As usual, just like cables there will always be different opinions. For myself, at least i have the comfort to know my equipments are fed with stable voltage and free from spikes!

I am an electronic repairman, by right china rating of 220Vac is not suitable for our usage.. You can get away from it, if you are lucky that your equipment able to take the overvoltage from the transformer. Some will fail prematurely...i have seen many and measure many equipment from china that measure way above the the designed voltage.

There are two type of avrs- linear and switching( relay). The linears are very expansive and the switching type is the most cheapest(jalan pasar) The switching type is recommended if your mains runs on generator where the mains fluctuates a lot. The witching type will switch to afew states depend on manufacturer. Say volytage is low from 165-220, the avr will step up to compensate or if the mains is high say 250 to 280V the avr will step down to compensate. therefore you can see that the regulation is no better than the specified 6% by TNB. Worst it generate surge or sparking when switches one state to one state...

Isolation transformer is best used if your equipement is not isolated from the mains i.e your tv set, to reduce cost and weight the tv set does not employ transformer to step down the voltage but rather use the FBT trans to provide power. zTherfore if you touch any expose part of tv or connected part like your vcr and dvd player. you will get tingling sensation, some are painful if your feet is wet...Therefore isolation transformer is employ to reduce this shock hazard.
It is also used for servicing station or electronic workshp to reduce shock hazard.

Back to your question, your tube comes with atransformer that isolate the mains to the rest of your amplifier circuit(but make sure it is grounded) You no need the isolation transformer. You have to measure the B+ whether the B+ is in the safe limit voltage of reservoir cap. Best is to make a step down tarsnformer from 240V to 220Vac

Most of the importer assure us that the China manufacturer says it is ok to use for our 240V ac....Do you belive them??? i have seen many failures and fabricated a few transformer to repair prosound equipment...Some even my personal electrical items i throw away, like the mist maker, to my horror when i open the unit, the caps is bulging and nearing to explode. Upon measuring the volt, it is above the caps rating..

Another thing i realise, the china people like to copy. Say if the circuit states require Vcc of 36Vdc....They will manufacture transformer ac rating of 36Vac. After rectification and filtering how much you get 51 Volts dc..

Sorry for boring you...

hoyhoysum,

not boring at all. Indeed you're giving a good explaination. I still believe, MIC still have their quality and also depends on the brand. Brand like Cayin, Audio Space , Consonance are reputable brand.


By the way, what do you mean by measuring B+ ?

hoyhoysum wrote:Best is to make a step down tarsnformer from 240V to 220Vac
>

Guys! You're in luck... I just found the invoice and the user manual for the single phase 3 wire system servo power regulator (Can be use to as step down transformer to 220V or if you are using US component 110V) I bought last year . INPUT 160 -270V - OUTPUT 220V or 110V(Manual wire transfer)

Confirm output is at 220V single phase. Construction is good. Jalan Pasar "STANDWELL TRADING" is selling this.The Regulator is from the same factory that produce "PowerBright" that is sold in US or UK.

Standwell the shop just rebrands it to SUNMAX I was told.
Its a Single phase 3000VA haevy duty toroidal regulator. More info at http://www.zonzen.com/svc-3000va-ac-automatic-voltage-regulator-avr.html



Its Priced at RM870 without any cables connected to it with 1 year shop warranty. You can Diy yourself on what power cable you want to use. I had some loose Oyaide and Supra cables with me and used it for this 220V regulator.

Tested it and output is a constant 220V with the volt meter. Once home, tried for a few hours and tried it with and without the regulator . There is a diffrence in improved sound stage, better layering and overall sound. Change the cable to oyaide and supra lorad for inout and output. So far, never regret. (oh yea, having a shunyata hydra connected to it).

Hope this helps.

hi, Opera,

may i know where to buy cayin and audio space in KL? i would like to get one.

thanks

mebbe some shops in AMCorp mall got sell...

i remember seeing alot of China hifi brands there.

Well said but what is missing is the filament voltage. This is the most critical part. Most tubes can take in higher B+. If u find your tube like red hot chili peper (that's too much), be careful.

My mains voltage can be as high as 247V. Our mains voltage is 240V / 50Hz, not 230V. It is only when loaded that 230V or lower appear (e.g u are at the far rec end)

Depending on what amp u buy, it will normally provide the tapping inside the amp and corrective is as easy as swapping it. U can take it to diy shop or our Electronic repair guy to do it.

My experience is even commercial amp requires some tweaking to get the optimum performance. Yes, no.

who knows XiangSheng Amp :

http://www.xshn.com/en/

Hi, I'm using a China made amp and I have open up to measure the voltages and find that its fit to use (for me atleast). The filament voltage is steady at 6V (if I remember well).

I am using a China amp & tube buffer too, both rated at 220V +- 10V but I still use a voltage regulater to step down the voltage to 225v+- as the output from my house outlet is at around 248v.

A good one like the AVIA PowerTrans Junior with Balanced transformer is very good, outlet voltage can be selected. Check it out from Audio Image. This is what I am using now.

ngheong wrote:hi, Opera,

may i know where to buy cayin and audio space in KL? i would like to get one.

thanks

Cayin is available at Ban Leong (Kepong) and the dealer for audio space is from Kedah (Superior HIFI Soundtech).

Opera wrote:

ngheong wrote:hi, Opera,

may i know where to buy cayin and audio space in KL? i would like to get one.

thanks

Cayin is available at Ban Leong (Kepong) and the dealer for audio space is from Kedah (Superior HIFI Soundtech).

thanks opera. i have found the contact for superior hifi soundtech, in sungai petani, and ban leong.