Jump to content

"Ghost notes" in my amp


dobermandan

Recommended Posts

  • Members
Posted

Hi Everybody,

 

This forum has really been helping my motivation to practice and learn more lately. Thanks!

 

I hope someone can help me with a gear problem.

 

I bought a 1965 Pre-CBS Fender Bassman head off eBay. I have no idea how old the tubes, transformers or filter caps are but the thing sound killer.

 

Problem is I can hear "ghost notes" on certain strings/notes. It's mainly when I play certain notes on the low E and A it sounds as if the amp generates an octave below on certain notes.

 

Any ideas what that could be and how to fix it?

 

Also,I amrunning the bassman head into a 16 ohm 2x12 cabinet. Is that the correct ohm match for that head?

 

Thanks a lot!

 

All the best,

Dan

www.dangallapoo.com

  • Members
Posted

It could just be the acoustics of the room. If you play a note centered on a frequency that your room has a mode at, it will do what I think you're describing. Try it in rooms with completely different designs and see if it does exactly the same thing in each one.

  • Members
Posted

 

Originally posted by clay_finley

You need new filter caps.

 

 

+1. Ghost notes are almost always the result of the amp acting like a mixer, and creating sum and difference frequencies of the input signal and 120 Hz hum from the power supply. New filter caps ought to take care of them.

  • Members
Posted

 

Originally posted by clay_finley

You need new filter caps.

 

 

+2, I had a very similar thing on a Bassman several years ago. Have a tech go through the entire amp while it's apart.

  • Members
Posted

Originally posted by dobermandan

Hi Everybody,


This forum has really been helping my motivation to practice and learn more lately. Thanks!


I hope someone can help me with a gear problem.


I bought a 1965 Pre-CBS Fender Bassman head off eBay. I have no idea how old the tubes, transformers or filter caps are but the thing sound killer.


Problem is I can hear "ghost notes" on certain strings/notes. It's mainly when I play certain notes on the low E and A it sounds as if the amp generates an octave below on certain notes.


Any ideas what that could be and how to fix it?


Also,I amrunning the bassman head into a 16 ohm 2x12 cabinet. Is that the correct ohm match for that head?


Thanks a lot!


All the best,

Dan

www.dangallapoo.com

 

It can also be your guitar. Have you played it through a different amp to make sure it isn't the guitar? I bought a usd American Fat Strat TS and it had that problem. Wierd overtones on the upper frets and dead spots in the middle frets. I took it to have the intonation set and neck adjusted and it's all better now. The truss rod was too tight. Thing sounds and plays great now. NOt saying it's definately your guitar, but you proably want to rule that out before you have the amp re-capped.

  • Members
Posted

Other than filter caps......

 

If you are using Celestion V30's or Greenback speakers, it is very common to get ghost notes with these speakers.

If you are not, I'd say you need a cap job.

Steve

  • Members
Posted

The first thing to look at is the filter caps. Many old Fender amps are out there with original caps. The earlier amps had less filtering than the later models which also contributes to ghost notes. You can have the filtering increased when the caps are changed.

Jerry

  • Members
Posted

The problem with not worrying about it is you'll go from playing ghost notes to playing smoke on the water as you watch your vintage power transformer and choke go up in smoke if a cap shorts. A cap job costs a few bucks, but a transformer costs more.

Jerry

  • Members
Posted

Thanks everybody for the info. Man, this place is a great resource!

 

Looks like I gotta dip into my measly savings account again and get a cap job. Oh well... I got a good deal on this head and it sounds killer so what the heck... it's only money.

 

Thanks again, everybody.

 

Best,

Dan

  • Members
Posted

Originally posted by clay_finley

You need new filter caps.

 

+3

 

I guess You need new filter caps. These are more or less drying up during some 10 years "generally" speaking, but they can last much longer.

I would bring the amp to a tech and have everything checked out.

Btw, some amps really have "ghost notes" no matter what, like some "Class A" amps (no brands to name... :cool: ).

 

Good luck with Your amp!

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...