Ceriatone Forum

Ceriatone => Overtone => Topic started by: max on March 27, 2008, 02:41:12 PM



Title: Noise
Post by: max on March 27, 2008, 02:41:12 PM
Hey All,
My amp seems really loud, When I got it it sounded wonderful but something is wrong now I think. I am not a tech but if I turn the amp up to say 6 on volume and 6 on master it is way too loud, I am talking about hum, it wasnt'nt there when I got it. The mid adjust doesn't seem to be ineffective and sound is buzzy when I overdrive it. I have 6l6's in biased to 38 mv.  I haven't done any mods it is stock and I am freaked out. Any thoughts. This is with all my guitars straight in no pedals. Help!!


Title: Re: Noise
Post by: Mitch on March 27, 2008, 03:47:50 PM
It's probably a loose tube in its socket- up-plug the amp from the mains & gently remove all tubes & look for any signs of stress- maybe scorching etc... carefully replace all making sure you replace the driver tube nearest the 6L6 power tubes with the same one you removed from that socket.  If that doesn't fix it- you may have a simple dry joint somewhere in the circuit but DO NOT ATTEMPT to fix unless you REALLY know what your doing- LETHAL voltages inside!  Get it checked over by a proper amp tech ...

Mitch


Title: Re: Noise
Post by: max on April 01, 2008, 02:10:05 AM
I just watched a power tube die right before my eyes, something is amiss the noise level is way beyond what it should be and I am giving up. This baby needs a doctor.  :'(

This is still one cool amp, and this problem will be cured, just frustrated

Doctor!!!


Title: Re: Noise
Post by: mcinku on April 01, 2008, 05:50:02 AM
Did you measured all the plate voltages?
If you did what are the values?

Mine looks like this:
6L6      452V
V1a      195V
V1b      204V
V2a      210V
V2b      213V
PIa      318V
PIb      301V


Title: Re: Noise
Post by: mcinku on April 01, 2008, 05:52:27 AM
BTW
... did you notify Nik about your problem?

He should have a few ideas about this.


Title: Re: Noise
Post by: max on April 01, 2008, 06:46:01 AM
Hey mcinku
Plate voltage 462 and using 6l6
this puppy is sick and needs to go to the doc, I can''t fix it, I contacted Nik but haven't heard back yet.
It will all work out in the end. Take care, It is late and I have to work tomorrow.
B


Title: Re: Noise
Post by: mcinku on April 01, 2008, 07:10:03 AM
Good night and let us know what happened to your amp once is fixed.

 ;)


Title: Re: Noise
Post by: ChrisL on April 02, 2008, 12:01:52 AM
Wbfree,

Bummer, but it happens.  My D'Lite is acting up right now and tracking down the elusive culprit is proving a challenge. 

 
Your OT,,

There are a myriad of possibilites but.....hum is usually indicative of a grounding issue so..

 pull your chassis,  discharge the caps, inspect every solder joint and reflow any joints that look suspect,  plug in some tubes you're not emotionally attached to for testing, do a rough bias, and get the measured voltages on all tubes and post them here.  If your voltages are ballpark correct we can then move on to the next step. 
Again, if you're not up to it, get a tech to do it.  But, really as long as you are safe and fully aware that the OT can "bite" it's a good chance to learn to do a little troubleshooting.


Title: Re: Noise
Post by: max on April 02, 2008, 03:04:36 AM
Chris,
Thanks for the reply. I don't feel comfortable doing this right now and it is covered under warranty. What I will do though is get with the tech who is going to fix it and find out what is wrong and when I get it back follow the circuit the way he did, if that makes sense. I really need to learn more before I stick probes in this puppy.  But I did look it over real good last night and saw no bad solder joints. 


Title: Re: Noise
Post by: jake on April 06, 2008, 07:34:46 PM
how are things going?


Title: Re: Noise
Post by: max on April 07, 2008, 12:56:39 AM
how are things going?
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Good jake, I sent it to Nashville to be looked at. Nik has been great, stuff happens and the problem if there is one will be fixed-no worries.
Burnie 8) :)