Power amplifier on/off

[raj_krish]

When I switch of/on my power amp, getting sound from speakers (drivers are moving in and out)
Will this damage the speakers

Sound produced is audible (doob) sound

 

[Audio_Freek]

Sir, Yes.Please check the Earthing there would be some issues.

I would get scared if i come across such situation (I have experience though).So How long you observing this issue? Is it sudden or prolonging for sometime now?

For best option, First Power on the Power ON the Power Amp later the Preamp and finally Source HTPC (I understand you use the same as Source)

 

[Danieljohn]

Raj no power thumps wont damage speakers infact we use to enjoy watching Cones move back & forth :lol: & I'm sure your speakers senstivity is more than 90 dB.

 

[raj_krish]

Yes they are 91db

 

[raj_krish]

Yes am using the same way as 1st switching on the power amp and after dac
It's from long time

 

[Audio_Freek]

So frequency is pushed into the Speaker via Amp,So it should be some noise for sure or cracking of the volume\Button in the amp or even there could be issue with the Spike in which you have connected the Power Amp.

For example if you just adjust the Plug when the amp is ON then you could feel the same noise. As per my observation its not really good sign but might be this affect only the High sensitive speaker.
There can be below reasons

1. Power supply issue in the Spike in which the amp is connected- So when a power supply is cut down in on of the plugs there could be some fluctuations in Line.

2. Bad Cable or damaged cable, If the Cable has any damage (could be very minimal) and when it get shaken or moved to touch any solid body the noise could be carried to power amp and reach speaker.

3.High sensitivity of the speaker might be an issue

So just try lending a speaker (with normal sensitivity) and try testing to observe the exact issue.

Have a separate power supply for power amp(in case you connect the amp and HTPC etc in same Spike)

Just my 2 Cents

 

[wucelope]

Yes am using the same way as 1st switching on the power amp and after dac
It's from long time

 

[raj_krish]

Tried by changing the cable and by connecting directly to the power port instead of spike.
But still find the same behaviour
Changed the speakers too..

 

[Soundstage]

Although I am no electronics expert, I do not believe that power thumps can be healthy for speakers!

I always switch on the source first, followed by the pre amp, then the power amp and last the speakers (if they happen to be powered). Switching off is in the reverse order. I understand this method is advocated by most of the reviewers too.

Moreover, it has been my 3 decade old custom to bring the volume down to zero prior to switching off my amp. This seems to be borne out by the ARC VSI 60 that I now own; whenever the amp is switched on, it is designed to automatically go into the 'Mute' mode for about 30 seconds before powering on. I am sure there must be a good reason for that!

Cheers

 

[Audio_Freek]

Although I am no electronics expert, I do not believe that power thumps can be healthy for speakers!

I always switch on the source first, followed by the pre amp, then the power amp and last the speakers (if they happen to be powered). Switching off is in the reverse order. I understand this method is advocated by most of the reviewers too.

Moreover, it has been my 3 decade old custom to bring the volume down to zero prior to switching off my amp. This seems to be borne out by the ARC VSI 60 that I now own; whenever the amp is switched on, it is designed to automatically go into the 'Mute' mode for about 30 seconds before powering on. I am sure there must be a good reason for that!

Cheers

+1 To that Source come in Power On and last in Power OFF in the chain.

Yes, Bringing the Volume to 0 is advice given when i was 4 Years i think. So Issue is, When some one power off the Amp when without bringing it to Zero then i cant control the Animal which is hiding inside Me. hyeah:

Coming to the original issues,

Since no change in the noise sent to Speaker ,It clear that no issues with the Speaker or the Speaker sensitivity.

So better check with a local electrician for the Earthing, I case you connect your amp in normal Plug ( Positive +Negative) then its time to move to the Plug with Earth too.

All the best, But keep these things serious , I have seen one of the Amp got to grave when the volume pot was full (Hope while cleaning it was turned by mistake) and when it was powered, due to the fluctuation in the Spike Left Channel was down completely.

Am Not scarring you, For me the Amps and Speakers are like Lovable pets, so they need some care and some time

 

[raj_krish]

My setup chain is Source is PC -> DAC -> PowerAmp

Even if i just switch on the amp and switch off, i can able to see the behaviour
Might be it is the behaviour of the amp

 

[Shivam]

Nothing to worry. It is a common behavior.

If you are into DIY and are not comfortable with the thump, there are multiple options available. some options -
Removing the DC Thump in Audio Circuits
http://sound.westhost.com/project33.htm

(It is always a good practice to switch the amps 'on' as the last in the equipment chain and switch them off first.)

 

[raj_krish]

Am not a DIY guy
I always switch off the amp first and switch on the amp last
So don't I need to worry with the behavior of the speakers?

 

[Danieljohn]

Raj Dont worry its just that your Amp is bit old type which I like such Amps sound fantastic so have fun & ther is no special earthing connection in your Amplifier but I hope your Amp has a 3 pin plug & proper ground is ther in plug points.

Hey Curious Audio Freak dont complicate & Scare Raj

You Truly are capable of Freaking us out:lol:

Chill Man

 

[raj_krish]

John
Yes the amp is not having the earth
Am using the three pin plug, but not sure about the ground as am using the spike

 

[Danieljohn]

Raj
I know for sure nothing will happen to your speakers.
But for your satisfaction just make sure the ground in amp "3 Pin Plug" is reaching properly to wall plug point ground.
PM Me your System details.

 

[cpt blood]

Hi.. the issue is commonly known as switch on ( off) thump. And it is one of the most difficult problems in a amplifier design. I don't think your lowering the volume will effect it. The only way to safeguard your speakers in inserting a relay ( solenoid) based delay circuit which connects the speakers 3 seconds AFTER you switch the main amp power supply. The same circuit disconnects the speakers INSTANTLY when you switch off the main amp power supply. And it is not a ''frequency'' but a stray DC voltage that is why in some cases you hear a WHOOMP or THUMP. if it is only moving the woofer diaphram and not producing any sound at all, then you can ignore it but if it is making the woofer sound coils hit the back end of it's assembly then you should look into it.
In a good amp this is one of the reasons they give a speaker disconnect switch on the front panel.See if yours has it.

 

[cpt blood]

And grounding will not work. This is the secondary side of the power transformer ( DC side) so kindly note that grounding will only add safety for yourselves.

 

[raj_krish]

Will adding a rely degrades the sound quality

 

[Danieljohn]

Raj No it wont if you are really :annoyed: with power thumps then go ahead with adding a relay delay circuit but make sure its done without nailing other areas.

I dont suggest such modifications something may go wrong So use a Power Conditioner with Sequencer feature or just an external Power sequence controller.