Mini Rec Ghost Note?

[soundchaser59]

I was tweaking my mini rec last night, no pedals, just guitar > amp > Weber Texas 10 speaker in a ported cab.

I was fine until I switched to modern mode, then every time I hit the low D note (5th fret A string, or 10th fret E string) I would get a very loud ghost note 1 octave down.

The tone knobs have no effect, turning the volume down has no effect (unless it's all the way off). It stops if I switch to any other mode. It's strange cuz I'm sure I've played this way before in modern mode, and had no problems, it just started first time last night.

Could a tube problem cause this? I hate to think I'm getting a resonance in the speaker. That low D would be about what......150hz? So a 75 hz resonance?

Any ideas?

 

[sparkle**]

Embrace it and make it your signature sound...It will catch on and you will be a hero...

 

[glip22]

I was tweaking my mini rec last night, no pedals, just guitar > amp > Weber Texas 10 speaker in a ported cab.

I was fine until I switched to modern mode, then every time I hit the low D note (5th fret A string, or 10th fret E string) I would get a very loud ghost note 1 octave down.

The tone knobs have no effect, turning the volume down has no effect (unless it's all the way off). It stops if I switch to any other mode. It's strange cuz I'm sure I've played this way before in modern mode, and had no problems, it just started first time last night.

Could a tube problem cause this? I hate to think I'm getting a resonance in the speaker. That low D would be about what......150hz? So a 75 hz resonance?

Any ideas?

I hate ghost notes. People tell me its my power or speakers or cab or one tiny thing vibrating in the room If its not the amp then why can I usually make them go away by working on the amp. Grounding, caps, lead dress, etc. My amps have zero ghosting. Not one bit at high volume and gain. Just clear articulate tone.

 

[soundchaser59]

I hate ghost notes. People tell me its my power or speakers or cab or one tiny thing vibrating in the room If its not the amp then why can I usually make them go away by working on the amp. Grounding, caps, lead dress, etc. My amps have zero ghosting. Not one bit at high volume and gain. Just clear articulate tone.

So, is there a suggestion somewhere in there? I suppose I can start by switching out tubes one at a time and see if that stops it. I'll try a different cab also, just be sure it isn't the speaker.

 

[glip22]

I hate ghost notes. People tell me its my power or speakers or cab or one tiny thing vibrating in the room If its not the amp then why can I usually make them go away by working on the amp. Grounding, caps, lead dress, etc. My amps have zero ghosting. Not one bit at high volume and gain. Just clear articulate tone.

So, is there a suggestion somewhere in there? I suppose I can start by switching out tubes one at a time and see if that stops it. I'll try a different cab also, just be sure it isn't the speaker.

Tubes have never fixed it for me but you can try by making sure your PI is balanced and your power tubes as well. If the amp is the cuprit ghosting can be caused by several issues. Poor grounding or a poor ground. Too much bass hitting the phase inverter. Poor lead dress, although I believe your amp is pcb mounted tube sockets. Signal wires such as preamp tube grids should be kept away from ac heater wires. Screen grid leads should be kept away from ac wires as well. Poor filtering is common. Most Marshalls will ghost at high volume. I usually up my mains filtering to 100/100 cans. Doesn't affect the feel much compared to upping the screen filtering. The screens are usually the culprit if non of the other things solve it. All push pull amps should have a certain amount of imbalance in the phase inverter. This gives the amp second order harmonics which is what you want. This is why Marshalls use a 100k and an 82k grid resistors I believe at the phase inverter. When this imbalance tilts too far in one direction you have ghosting. This is when it is most hardest to solve. Thats when you have to try lowering the coupling cap values, and some other resistors in the PI circuitry. Very rarely it can be the power transformer sagging too much under power. Its hard to tell this. Usually if the transformer has been stressed or is very old.

 

[glip22]

I was tweaking my mini rec last night, no pedals, just guitar > amp > Weber Texas 10 speaker in a ported cab.

I was fine until I switched to modern mode, then every time I hit the low D note (5th fret A string, or 10th fret E string) I would get a very loud ghost note 1 octave down.

The tone knobs have no effect, turning the volume down has no effect (unless it's all the way off). It stops if I switch to any other mode. It's strange cuz I'm sure I've played this way before in modern mode, and had no problems, it just started first time last night.

Could a tube problem cause this? I hate to think I'm getting a resonance in the speaker. That low D would be about what......150hz? So a 75 hz resonance?

Any ideas?

Ghost notes will not present themselves this way. You should have them on more than just two frets. It may be a resonant freq in your speaker. Try a different speaker. I don't think its your amp.

 

[soundchaser59]

The amp is basically new, less than 1 year old, manufacture date is January 2012 according to Mesa tech. All original Mesa tubes, which (in my experience) are notorious for having problems almost out of the starting gate. Anyway, all the caps and transformers, etc. are good as new, but doesn't mean there isn't some defect in there somewhere.

I'll try a different speaker cab here in a bit. Then I'll try swapping out tubes.

There is some small rumor of the Weber Texas having cone cry issues, but that's always been the high notes, not the low ones. I only mentioned two different frets just to point out that it happens on the same pitch no matter where I play that note on the guitar.

 

[Stramm8]

Is the cabinet sitting directly on the floor? Could also be something out of whack with the set up on the guitar.

 

[soundchaser59]

Cab is on a stand. Had the guitar for 15 years, never had any issues with it, same pro luthier setup it's always been.

 

[Stramm8]

Cab is on a stand. Had the guitar for 15 years, never had any issues with it, same pro luthier setup it's always been.

Ok, I'm out

 

[soundchaser59]

Well, now I'm suspecting a speaker issue.

I plug into the bigger cab with Michigan speakers in it and there is no ghost note at all.

If I plug the 8 ohm Texas 10 into the amp's 4 ohm jack, the ghost note does not happen.

I was wrong above.......if I turn the bass knob all the way off the ghost note stops. Or turn the gain down to a soft twang, it stops. If I switch to 10 watt setting it stops. But changing to the mismatched 4 ohm jack stopped it, and that (to me and my limited understanding) points to a speaker issue.

 

[soundchaser59]

Stuffing the void space inside the cab with batting stopped it.

 

[glip22]

Stuffing the void space inside the cab with batting stopped it.

All I saw at first was ghost notes and I hate them. Sorry for the lengthy post. Speakers/cab are the first things to rule out. I had a ghost in am amp and I immediately changed speakers which solved that one. Just because one amp doesn't ghost through the cab, doesn't mean another will not. Its all about the frequencies. Glad you solved it.

 

[soundchaser59]

It may be a resonant freq in your speaker. Try a different speaker. I don't think its your amp.

WINNER!

Turned out to be "cone cry" in the Weber Texas. The straight smooth cone is apparently the type of cone that is most susceptible to cone cry, and (in this case) no amount of doping fixed it. Got a different speaker and no more ghost notes. Didn't have anything to do with the amp or the guitar.