Crosspost from
http://www.hifivision.com/audio-video-accessories/15235-power-games-servo-stabilizer-cvt-online-ups-38.html#post300622
I have a Yamaha DSP A1 (500 W) and a Hsu Subwoofer Amp (1100 W) both requiring 120v power supply. I wanted to buy a solution that would condition the power, have surge protection and also step down to 120V. After some research I located a small company called MAKSON ENGINEERS in Borivilli, Mumbai. (Pls PM me for contact details). It is a small but very professional setup. I visited their shop floor. It was very clean and dust free, open chassis showed well laid out components and interacting with their engineers I felt confident they knew their job well.
I initially wanted to buy a CVT, but after describing my requirements and taking their advice, I finally got a 3 KVA online UPS and a separate isolation transformer (step down). Since I did not go in for frequency conversion (they could do it too, but too costly), I made them give me 3 tappings for the step down transformer, at 110, 115 and 120V. This is because I read that if your amps run hot in 50hz, then reducing the voltage a bit helps.
The key thing for me is that, I found a company that was willing to produce a custom built solution for me based on my requirements, with good components and good quality. The final body finish is not as shiny as some branded products, but I'm very happy to know the insides are well designed and that I can call them any time I have a problem or needed modifications. For eg: they can change the UPS parameters (output voltage etc) by simply tuning it with a software from a PC.
I've used the product for a month now and so far it works very well. The step down transformer is absolutely silent, no hum at all. The UPS is silent, but the fan is quite busy. Every time the load goes up, the fan goes into overdrive. So its not good to keep in the same room as the AV equipment. I installed it near the mains in the line that goes to the AV room.
The total cost came to Rs 29,500, which I thought was not bad considering both UPS and the Isolation step-down transformer are rated 3 KVA each.
If you are in mumbai and looking for a custom solution for UPS, sbatilizer, step down transformer etc, I would strongly recommend that you talk to MAKSON too.
regards,
Dovin
ps: Both my amps have no issue at all with 120v/50Hz - Absolutely no hum or running hot, so the 3 tappings were not needed in the end.
....waiting to be cleared. Got my AVR on time.
1kva