[bkling]

Dear Forumers

Whenever I turn on my tube Headphone Amp, I notice there is quite a big "Hummm" sound in my AKG K701 which last for 2 seconds then gradually dissapeared. As I worry this humm sound would damage my AKG K701, I normally plug into the jack after turning on the Amp and then plug out before tuning off the Amp. But then, it is kind of inconvenient to me to repeat these steps everyday.

Any brothers here have experienced this in their setup or can share the solution to solve this?

 

[ZephyrSapphire]

I read somewhere about tube amps that you're suppose to plug your headphones in first before turning them on and switch the amp off before taking them out?

 

[Sovkiller]

IIRc you are doing the opposite, the heapdhone should be plugged in while turning the amp on, and removing it after a few seconds it is off...I leave mine always plugged...

It could be a noise from the PSU while caps are charging, but in any case you should check that with the manufacturer or other owners, to see if this is normal...

 

[bkling]

Quote:

Originally Posted by Sovkiller /img/forum/go_quote.gif IIRc you are doing the opposite, the heapdhone should be plugged in while turning the amp on, and removing it after a few seconds it is off...I leave mine always plugged... It could be a noise from the PSU while caps are charging, but in any case you should check that with the manufacturer or other owners, to see if this is normal...

If it is charging issue, we should plug in the jack after the PSU turn on for 10 sec (Charging) and plug it out before it is turned off (De-charge) to avoid damanging on the HP.

 

[Sovkiller]

Quote:

Originally Posted by bkling /img/forum/go_quote.gif If it is charging issue, we should plug in the jack after the PSU turn on for 10 sec (Charging) and plug it out before it is turned off (De-charge) to avoid damanging on the HP.

Again as a general rule and to avoid some noises, you should plug the heapdhone in before turning the amp on, and removing them after it is off...if you are convinced that you should do in the opposite way, why asking here...then???

Now you should check if this is normal or not in your amp with the manufacturer...IMO it is not, and if it is a charging/dischaging issue, you should fix it, as you should not hear any hum while the caps are charging or discharging, usually they make a noise but in the majority of the cases it is not a hum...

 

[digismurf]

I thought you could blow an amp unplugging your headphones before turning it off first...or maybe that's urban legend?

 

[squall343]

Quote:

Originally Posted by digismurf /img/forum/go_quote.gif I thought you could blow an amp unplugging your headphones before turning it off first...or maybe that's urban legend?

not really true...mine darkvoice is still not blown yet

but i try not to do that...

 

[Thermofreak]

ya, I have read from somewhere that it is always turn on the source first, then your amp....to avoid the noise from the source being amplify by the amplifier and resulting damage to the HP/speaker.

Then, I have also read from somewhere stated that(should be from tangentsoft), you could blow your amp if you happen to short the ground while plugging or unplugging the HP from the amp WHILE it is ON

 

[oicdn]

I would think that while the freak possibly may be there for you to blow an amp from that happening, it's unlikely.

Why? Because people at a whole are careless and/or stupid. You could specifically tell somebody not to do something and they'll end up doing it sooner or later.

If that were the case, there would be many blown amps and warranty returns under "I dunno What happenned, I just unplugged my headphones and now it doesn't work" claims. Talk about losing alot of money....

Then again...it really could be the possibility, but between me A/Bing alot of stuff, it's never happened to me.

 

[Sovkiller]

Quote:

Originally Posted by Thermofreak /img/forum/go_quote.gif ya, I have read from somewhere that it is always turn on the source first, then your amp....to avoid the noise from the source being amplify by the amplifier and resulting damage to the HP/speaker. Then, I have also read from somewhere stated that(should be from tangentsoft), you could blow your amp if you happen to short the ground while plugging or unplugging the HP from the amp WHILE it is ON

That is why isa common practice to place an small resistor value at the output, to avoid it to be shot...if you short the output, you will have the resistor as load, so it will serve as an small load, but not 0...