Ceriatone Forum

Ceriatone => Overtone => Topic started by: jgamble on September 12, 2008, 11:38:15 AM



Title: question about noise floor on the OTS
Post by: jgamble on September 12, 2008, 11:38:15 AM
I have a question and was wondering if anyone could give me some feedback to help me understand if the amp is behaving normally....  bear with the long-winded nature of my post, please...

I can easily set the amp at 8 or 9 on the volume control and 1 or 2 on the master volume, turn on the distortion channel, and have a very nice distortion sound with no background noise from the amp.  I can also turn the master volume up high and put the volume on 1 or 2 and get great cleans on the normal channel without any background noise from the amp.  No hum or anything when I'm not strumming or picking notes.  It's just dead quiet.

However, when I  turn both the master volume and volume up to say, 5, the amp starts producing noise.  It's not hum, it's more like, well, background white noise.  When I play you can't hear the noise, just if you let the amp sit there.  (Also, I can unplug the guitar input and it makes no difference on the noise).  If I turn the MV and V up to max the background noise is louder.  It's not obnoxiously loud, but it's there.

is this normal?

Thanks!


Title: Re: question about noise floor on the OTS
Post by: Pickmaster on September 12, 2008, 01:07:21 PM
Hi,
 If you are using FET input, you will have “white” noise – it is transistor hum.
On normal channel hum must be almost unnoticeable.
When you plug in to the NORMAL input, FET is automatically disconnected. But if there is some factory  soldering mistake and FET does not disconnect you will have a hum.
Hope this helps.


Title: Re: question about noise floor on the OTS
Post by: jgamble on September 12, 2008, 01:47:50 PM
Thanks, I will double check the FET wiring but what I was getting at is that it only happens at higher volumes. 

Are you saying your amp is dead quiet with nothing plugged into either input and the volume and master volume turned up all the way?  I guess what I'm asking is how much noise is reasonable. 






Title: Re: question about noise floor on the OTS
Post by: Pickmaster on September 12, 2008, 02:50:07 PM
jgamble,
My amp has only normal input! and volume on 5 and master on 5 it is VERY quiet. If you put them on 10 amp obviously will produce some noise.
I also use T.C. Electronic G major in the loop and it’s noise gate is always on! so my amp is really dead quiet (and noise gate DOES NOT affect the tone, feel or playability!!!).
Cheers


Title: Re: question about noise floor on the OTS
Post by: jgamble on September 12, 2008, 04:24:51 PM
Pickmaster,

Thanks.  Maybe I am just being uptight for no reason.  I compared it to another amp I have, an AC15, and they both make the same kind of background noise as I turn them up.  I think the OTS is just louder because, well, it is louder.




Title: Re: question about noise floor on the OTS
Post by: Mike on September 14, 2008, 05:08:27 PM
Mine is producing hum / hiss starting with Master set to 1, irrespective of what the volume is set to. That is for strictly clean channel. And that is for the amp alone - without anything plugged in. However, I am using the amp in a quite small room with a Mesa Thiele Cabinet (C90, sensitivity 99db). That contributes to the perception, too I think. However, everybody thinks that this is normal ? It may be but I am not sure. Any help is appreciated.
Mike


Title: Re: question about noise floor on the OTS
Post by: Mike on September 15, 2008, 03:06:38 PM
Just learned something:
1. Do not sit in axis with the speaker
2. Put the amp as far as can be from the guitar
3. put the speaker cabinet in a reasonable distance from your playing position (that is at least 2m)

I then put in a Kleinulator without effects, set it to 14:00 "Send", 17:00 "Return" and about 11:45 ;-) "Recovery".

If you like that you may turn down treble. I actually put it to 08:00.

I then may go Master=4 and Volume=4 with all preamp switches down and get a clean tone at bedroom level without hum/hiss at the listening distance. If you switch then the Jazz to Rock Switch hum level is not much augmentend but loudness is.

This means that I feel already much more comfortable with the OTS !  :D Seems to be all a knowhow thing (Nik helped a lot), takes time - looks like the secret is in not giving up.

Next step for me is the cabinet. A Mesa Thiele 12" closed back may be a fine thing, but might not be what is required here.