Frying JBL K2 S9800 with Parasound JC1

[Loffen]

Hei

I am a Norwegian guy running a Parasound/JBL set up.

Last weekend we had a AVforum meeting at my place,we are a bounch of guys serius about sound,but we also like to have a high "Fun factor".

My set up was Parasound C2,D3 and a pair of JC1 together with a pair of JBL K2 S9800.

This was run as a stereo set up run in the bypass mode through the C2 and the speaker gain (in the sub menues) was set to 0 db.

Anways after some listning playing on -10 t0 -5 db on the volume ( it goes to + 15 db) we pushed it up to 0 db.

Everything went fine for about 20 seconds with out any clipping or distorsion then we could smell that something was not right and smoke started to come out of the crossovers in the K2s

The result was two burnt resistors ( 33 ohm 5 w) in the HF board on both speakers ( in the picture if it uploades)

My question is why this happend ?

This is a topic in another forum,but I am not shure if I can post a link here without braking any rules (and I will not brake any rules in my first posting)
I could answer most on the posts there in Norwegian but my English is not so good...

Anyways my hope was that Mr Curl could take a look at the tread and maybe fill in on some of the questions since the amps and the Parasound system is taking some beating

 

[SY]

Feel free to post the links, that's not a problem. Neither is your English, which looks fine to me.

If the amp survived this, it did its job. I think your complaint might be with the speaker manufacturer. But maybe not even there- I'd rather a cheap crossover component fail before the expensive (and perhaps irreplaceable) drivers.

 

[Loffen]

Thanks Sy

Here is the link : http://www.audioheritage.org/vbulletin/showthread.php?t=21389

Any ideas would be great.

The set up was used after this happend for several hours with other speakers no problems at all

 

[john curl]

You apparently 'smoked' your crossover with too much input level.

 

[Loffen]

Thank you for your answer Mr Curl.

So you do not think that it is due to signal distorsion,"clipping" or driving the JC1 out of it 's range ?

Would this have made any damage to the amps ?

And last,how does the protection circut work ?
I have been thrugh the manual and the Parasound pages and I am not able to find any information,except that the circut is there.

Best regards

Espen

 

[john curl]

You ask many questions that I can not answer. The JC-1 is a very powerful amplifier (800W into 4 ohms) rated and will burn resistors or even loudspeakers, if they are not able to stand the power. It is difficult to 'clip' the JC-1 because it has such large output swing, AND it has almost unlimited peak current. Just look at the peak power rating in the 'Stereophile' JC-1 review.
I do not use the JC-1 to drive my WATTS, because it is too powerful for them, and I cannot afford to break them accidently. They are primarily designed for powerful home theater systems and large electrostatic speakers and they do well in this mode.
You might do better with a Halcro, in that it is limited to 15A PEAK output current.

 

[Loffen]

Thank you Mr Curl

Mr G. Timber did answer in the other post and had the same conclusion as you,he did also offer to send me some new resistors that will handle the power better (Not that I am going to play at the same level again).

I truly love the JC1's for it's sound and not at least it's power and I do not belive that there is any amps out there that is even close to it in it's price segment.

And last thank you for giving me a smile on my face every time I turn my system on

Have a nice weekend !

Best regards from Norway

Espen Heitmann