[fl00r]

To make a long story short: I rolled tubes on my newly acquired DV336i, switched the amp on with my K701 plugged in and there was a very nasty noise coming from the left cup. Now the sound of left channel is very soft. The right driver is functioning OK.
I guess there was some sort of peak voltage that ruined the driver?

 

[NiceCans]

first try to isolate the problem, perhaps try another source to see if the amp is off-balance

 

[Capunk]

Happens to my old PK-1 & Xin SM3 v6 amp, my left driver volume become softer, and right one still normal.

 

[Blackmore]

Check the tube, can be dead. Otherwise check FS forum for my Aspen.

Quote:

Originally Posted by fl00r /img/forum/go_quote.gif To make a long story short: I rolled tubes on my newly acquired DV336i, switched the amp on with my K701 plugged in and there was a very nasty noise coming from the left cup. Now the sound of left channel is very soft. The right driver is functioning OK. I guess there was some sort of peak voltage that ruined the driver?

 

[fl00r]

Quote:

Originally Posted by NiceCans /img/forum/go_quote.gif first try to isolate the problem, perhaps try another source to see if the amp is off-balance

Apparently there's nothing wrong with the amp because I tried another headphone and inears without a flaw, same source, same tube.


Quote:

Happens to my old PK-1 & Xin SM3 v6 amp, my left driver volume become softer, and right one still normal.

What happend after? I hope they can reanimate my K701's......

 

[Tech2]

Quote:

Originally Posted by fl00r /img/forum/go_quote.gif Apparently there's nothing wrong with the amp because I tried another headphone and inears without a flaw, same source, same tube...

I would roll back to the old tubes anyway, and try again. The 701s are pretty demanding headphones. I'm thinking that another headphone might work fine with a 'marginal' tube but the more hungry 701s might bring out the worst in such a tube. Worth a shot, IMO.

 

[tf1216]

Yes, sounds like an amplifier problem. Don't lose faith.

 

[dcstep]

Read what he said, it's not the amp. The 701s may be slightly hard to drive, but one side will not sound different from the other side in a working pair. Apparently a surge ruined them.

Dave

 

[fl00r]

How can you tell a faulty tube from a good one?

I notice the 'killer-tube' (a 6080) giving some sparkles for a moment (in the bottom of the tube) when I power up the amp. I am just a beginner when it comes to tube-amps and don't know whether this is normal behavior.

Thanks for your concerns.

Ben

 

[Blackmore]

To much noise, one chanel weaker or cracking...


Quote:

Originally Posted by fl00r /img/forum/go_quote.gif How can you tell a faulty tube from a good one? I notice the 'killer-tube' (a 6080) giving some sparkles for a moment (in the bottom of the tube) when I power up the amp. I am just a beginner when it comes to tube-amps and don't know whether this is normal behavior. Thanks for your concerns. Ben

 

[fl00r]

Quote:

Originally Posted by Blackmore /img/forum/go_quote.gif To much noise, one chanel weaker or cracking...

Well the left channel was definitely cracking.
I find it surprising that there is no such thing as a fuse to protect from a surge.

Nothing left to do than cross my fingers and hope for a good customer service from AKG.

 

[Happy Camper]

Quote:

Originally Posted by fl00r /img/forum/go_quote.gif Well the left channel was definitely cracking. I find it surprising that there is no such thing as a fuse to protect from a surge. Nothing left to do than cross my fingers and hope for a good customer service from AKG.

Sparkling tubes are not a good sign. Change tubes before sending your hps out.

In the future, turn your volume knob off when powering up/down an amp.

 

[jona.p]

Heh, yeah first thing I would try is swap the tubes back. I had a crackling problem with my power tube, also thought it had a slight volume balance problem. Put in a new good one and it works great !

I don't think your supposed to see sparkles inside your tube.

 

[Roam]

Quote:

Originally Posted by fl00r /img/forum/go_quote.gif I notice the 'killer-tube' (a 6080) giving some sparkles for a moment (in the bottom of the tube) when I power up the amp. I am just a beginner when it comes to tube-amps and don't know whether this is normal behavior.

The sparks are caused by the tube arcing over, in other words, the tube is a goner. Replace it before it has a chance to damage your amp or your other headphones.

 

[dgbiker1]

I hate to be captain obvious here, but have you tried plugging the K701s into another source to be sure it's the K701s that are damaged?