UPS for AMP ?

[reignofchaos]

At the time i wrote my previous post, i read this differently in haste and hence my comment. Sorry bout that.

However, I still would like to know how everything sounded better with an UPS? Anyone?


This should not happen if UPS with the required KVA is used. Would like to know what devices are connected to the UPS, what are they rated at (power rating at the back panel), and the power factor of each device.
I presume you have connected UPS to the 15 amps line and not the 5 amps.

No worries! The ups is rated at 1980W/2200VA output with a peak current input of 10.2A. I tried connecting it to the exact same wall socket. The other devices connected to it were a CD player and a preamp both of which should not eat more than 100W combined. I even tried with nothing else other than the power amp connected to the wall socket.

In both the above cases, I found the sound to be slightly muffled with dynamics and bass slam lacking the impact compared to when the power amp was directly connected to the wall socket.

However when I connect the preamp and the cd player direct and compare it with them connected via the UPS, there's a very discernable difference - the sound is a lot cleaner via the UPS.

As I said these are my observations. Your mileage may vary.

Here's the UPS in question -

APC Smart-UPS 2200VA USB & Serial 230V

 

[ShaQ.Blogs]

If a UPS with insufficient ability to supply power is used, it should soon start flashing errors and even shut down. I mistakenly plugged in a laser printer to a UPS outlet: the UPS would not start, I got nothing but the overload warning light.

+1
In my older low capacity UPS, the amp used to either restart or switch off. I had suspected that it might not suffice, but since I had an UPS at hand to check if it will work out, but it didnt at high volumes when bass was played from the front towers. It was rated .5 KVA.
I then calculated and the minimum I required was 1 KVA. Got another UPS, and since then no issues.

 

[ShaQ.Blogs]

You've got me confused here

Here you mentioned dynamics were constrained,

Agreed! I have a 2 kVA APC Smart UPS and it seems to constrain the dynamics with the power amp plugged into it.

and here you say it sounds better with UPS

However when I connect the preamp and the cd player direct and compare it with them connected via the UPS, there's a very discernable difference - the sound is a lot cleaner via the UPS.

Maybe yes, maybe no. I do not know.
But, I would like to understand *technical how* it could sound better with an UPS?
Could voltage fluctuations have an impact? If yes, how? Could a drop in voltage effected a drop in the rail voltage which is seen by the load.

If someone understands and could explain would be great.

 

[2chFreak]

In both the above cases, I found the sound to be slightly muffled with dynamics and bass slam lacking the impact compared to when the power amp was directly connected to the wall socket.

However when I connect the preamp and the cd player direct and compare it with them connected via the UPS, there's a very discernable difference - the sound is a lot cleaner via the UPS.

:thumbsup: .. 100% in agreement.

Depending on the power conditions, one needs to ascertain whether is it safe to plug the Pwr amp direct or not.

Places like Gurgaon is not. You def need a high quality no-nonsense online UPS or you'd be sorry but Bangalore should be ok.

 

[saralaprasannan]

In my opinion, three things about UPS has to be taken into consideration when connecting to HI-Fi

1. Power rating - Atleast two times the AMP's rated power consumption.

2. Power factor - Improved PF is a must for power transformers in AMP. (in UPS it is between 0.8 - 0.9, where in supply line PF = 0)

3. Output Wave form - Full sine wave instead of quasi-sine wave.

 

[Kittu]

What about the noise (Fan) from UPS? Smart or online they should be making some noise , and I do not think it is advisable to keep them close to the HT setup.

People using the UPS already can share some knowledge here.

 

[Shyamtanu]

I have a multi stage protection which you may find useful. I have a surge protector right after the power meter so it takes care of low voltage, over voltage even before it hits MCB box. Then I have a almost whole house covered inverter (APC) + surge protection for all electronic/electrical items minus 15A lines heavy consumption points. For stereo, I use GM power cord with surge protection (a very nice quality indeed), finally APC 800 VA protection for CDP + Amp which I have kept under the audio rack itself. One observation, no sure how it works, I used to use a bad/normal quality power cord from the wall socket earlier, never minded anything, but the GM one has changed something as the power delivery seems to be improved, though I was not believer of such perceptive changes in sound due to power cable!

 

[Thad E Ginathom]

What about the noise (Fan) from UPS? Smart or online they should be making some noise , and I do not think it is advisable to keep them close to the HT setup.

Mine is neither smart nor online, and it only makes fan noise when actually running on battery: otherwise it is silent.

 

[Cnu]

Home Solutions | UPS - Pure Sine Wave | Fusion Series

 

[2chFreak]

If one has serious highend equipment and lives in one of those awful power zones, he should honestly consider this product. Its also certified for Highend Audio.
PurePower Audio Power Supply

However, its expensive & will only work out for those who has plonked in a good amt of money towards audio gear.

 

[Staxxx]

What about the noise (Fan) from UPS? Smart or online they should be making some noise , and I do not think it is advisable to keep them close to the HT setup.

People using the UPS already can share some knowledge here.

My APC UPS fan makes quite a buzz, loud enough for me to moved it to my balcony and make extra long power chords.

 

[Thad E Ginathom]

Probably similar to our APC inverter, where the fan runs both when the unit is running off batteries and when it is charging. It is like an uncontrolled 80mm fan on an old PC: very loud. It is not in living space, so it doesn't matter. I wouldn't want it to be.

Do the fans on all online UPSs run all the time?

 

[Staxxx]

Yes Thad. Mine is an online UPS and it is always running.

 

[Kittu]

I think all types of UPS will make some noise and generate some heat , so potential buyers better plan to keep it far away from the HT system/room and run long cables. (Tough task if the setup is already in place).

 

[baijuxavior]

My UPS fan makes noise when it is connected to mains for charging. When ups is turned on another fan starts working adding to the noise. I am planning to put the ups in another room due to this intolerable fan noise.

 

[Thad E Ginathom]

I think all types of UPS will make some noise and generate some heat

As said, except during the power cut, mine makes no noise at all as the fan does not run except when discharging. Even then, it makes less noise than a ceiling fan or AC.

Lessons have been learnt. If I ever get to wire a house again, I will make provision for all this stuff at the distribution board, out of the living space --- and also be a lot more careful about what shares the same phase. One change I could make easily was to run hifi and AC in the same room off different phases. The AC compressor startup was causing the amp to power off.