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]-[ @ n $ 0 |v| a T !
05-09-2012, 12:24 PM
Hey EM7,

How do I get rid of that @#$%^ ghost note problem in by Bad Cat TremCat 30 1X12 combo? The only way I can play the amp without hearing ghost notes is in 15 watt mode with a 1X12 extension cab added and the amp set at 4 ohms.

When I am running the amp with the single 12" speaker (no extension) at 8 ohms, the ghost notes are absolutely intolerable.

What am I calling a ghost note? The deliberate note I'm playing comes through loud and clear along with another "ghost" note at around 50% of the deliberate note's volume. The ghost note is a sour discord in a different key than the deliberate note - not at all similar or complimentary.

OsirisProtocol
05-09-2012, 12:33 PM
I had that issue awhile back and all it took was lowering the bass side of the pickup a bit. Not sure if it will help you but its worth a shot.

Em7
05-09-2012, 04:33 PM
Ghost notes are often the result of speakers that have been lightly doped or had some of their doping removed. I would try a speaker swap.

The Ratchet
05-09-2012, 04:41 PM
Does it happen with all your guitars? Or just some? And if so which?

In my experience, one of the biggest culprits in ghost notes popping out is a guitar's trem system, and it seems that some amps bring it out more than others. So if it happens with your trem guitars, and not with your stoptails, it could be something guitar related, and need to dampen the springs.

Not familiar with that particular amp, but I'm pretty sure Bad Cat's are discussed somewhere or another on the web. Even peeps on TGP might now. Could be something in the amp's circuitry also producing a similar effect. I hate weird harmonic overtones like that, that are musically bizarre.

]-[ @ n $ 0 |v| a T !
05-09-2012, 04:50 PM
Thanks for the input, gents. It does this regardless of the guitar. It is only tied to volume, ohm load, and speaker configuration (one or two).

Let me experiment based on this input and get back to you.

EM7, What is a "doped" speaker???

No political jokes, please. :lol:

Em7
05-09-2012, 04:59 PM
Thanks for the input, gents. It does this regardless of the guitar. It is only tied to volume, ohm load, and speaker configuration (one or two).

Let me experiment based on this input and get back to you.

EM7, What is a "doped" speaker???

No political jokes, please. :lol:

Doping is the shiny stuff that is around the edge of a speaker cone. It helps to control unwanted speaker movement.

]-[ @ n $ 0 |v| a T !
05-09-2012, 05:42 PM
So are ghost notes the same thing as "cone cry?" After reading this thread on TGP I am left wondering if I shouldn't try adding some doping to the cone (as a first attempt to resolve the issue) rather than going for an expensive speaker change.

http://www.thegearpage.net/board/showth ... p?t=939146 (http://www.thegearpage.net/board/showthread.php?t=939146)

Thoughts?

The Ratchet
05-09-2012, 06:00 PM
When other people listen to the amp do they hear the same thing?

These strange notes, do you hear them other places, at other times? Just sayin.... :mrgreen:

LSchefman
05-09-2012, 06:26 PM
Hey EM7,

How do I get rid of that @#$%^ ghost note problem in by Bad Cat TremCat 30 1X12 combo? The only way I can play the amp without hearing ghost notes is in 15 watt mode with a 1X12 extension cab added and the amp set at 4 ohms.

When I am running the amp with the single 12" speaker (no extension) at 8 ohms, the ghost notes are absolutely intolerable.

What am I calling a ghost note? The deliberate note I'm playing comes through loud and clear along with another "ghost" note at around 50% of the deliberate note's volume. The ghost note is a sour discord in a different key than the deliberate note - not at all similar or complimentary.

Hans, there's a fairly simple way to see if it's the amp's innards or a speaker, and that's to disconnect the internal speaker and run the extension cab by itself. Try the amp with the extension speaker in all of its modes. If it doesn't happen with the extension speaker, it's the speaker. If it also happens with the extension speaker, it's probably the amp, and it would be a good idea to send the chassis to Bad Cat for a look-see.

I had this problem with a Tremoverb, exactly as you describe. A speaker swap fixed it in my case.

]-[ @ n $ 0 |v| a T !
05-09-2012, 07:23 PM
When other people listen to the amp do they hear the same thing?

These strange notes, do you hear them other places, at other times? Just sayin.... :mrgreen:
Strange that you should mention it... I'm responding to a strange note right now!

s.fitzsimmons
05-09-2012, 11:03 PM
I remember this being a problem being discussed on the MetroAmp forums and often tied back to power filtering (not enough) or an incorrectly rated choke for the design of the amp. Not sure if it applies to a Bad Cat or not, but might be somewhere to start.

vchizzle
05-10-2012, 11:19 AM
Hans, have you called/contacted Bad Cat at all? They've been pretty helpful when I've had questions/issues.

]-[ @ n $ 0 |v| a T !
05-10-2012, 11:46 AM
Hans, have you called/contacted Bad Cat at all? They've been pretty helpful when I've had questions/issues.
Vaughn,
I agree, James is a good man and has done lots of custom work and repairs for me in the past. But I have learned (the hard way) to get an understanding of the problem before I request (and fund) repairs. Many times the "fix" can be accomplished in my own shop - which is my preference. This seems like a problem that is either inherent in the design of the amp or a part that needs to be replaced or tweaked - something I can do myself. If it's a design issue and their is a fix, I'll send it back to James (or whoever owns Bad Cat now).

If I can't hack it, I don't own it! ;)

I still need to experiment with different speakers, as suggested by EM7 and Les but I still want to know:
1) If ADDING doping to a speaker could resolve the issue, and
2) If "cone cry" and "ghost notes" are the same thing.

Em7
05-10-2012, 12:03 PM
So are ghost notes the same thing as "cone cry?" After reading this thread on TGP I am left wondering if I shouldn't try adding some doping to the cone (as a first attempt to resolve the issue) rather than going for an expensive speaker change.

http://www.thegearpage.net/board/showth ... p?t=939146 (http://www.thegearpage.net/board/showthread.php?t=939146)

Thoughts?

Do you own another amp or cabinet that uses the same size speaker? The goal here is to rule out the speaker as the cause of the problem. Identifying an amp problem is just like troubleshooting any other type of system problem. One needs to change one variable at time until the cause is found. The usual suspects should be tried first. In this case, the first thing to try is a simple speaker swap.

You also need to look for cabinet resonances. Not all birch plywood is completely void free.

]-[ @ n $ 0 |v| a T !
05-10-2012, 12:08 PM
You can rest assured, I am going to try a speaker swap - as suggested - this weekend.

I'd still like to know, if you can shed some more light on the issue:
1) If I confirm that the problem is being caused by the speaker, is it a reasonable next step to add doping to the speaker to try and resolve the issue? I don't want to buy another speaker unless I have to.
2) are "cone cry" and "ghost notes" the same thing.

vchizzle
05-10-2012, 12:25 PM
Hans, have you called/contacted Bad Cat at all? They've been pretty helpful when I've had questions/issues.
Vaughn,
I agree, James is a good man and has done lots of custom work and repairs for me in the past. But I have learned (the hard way) to get an understanding of the problem before I request (and fund) repairs. Many times the "fix" can be accomplished in my own shop - which is my preference. This seems like a problem that is either inherent in the design of the amp or a part that needs to be replaced or tweaked - something I can do myself. If it's a design issue and their is a fix, I'll send it back to James (or whoever owns Bad Cat now).

If I can't hack it, I don't own it! ;)

I still need to experiment with different speakers, as suggested by EM7 and Les but I still want to know:
1) If ADDING doping to a speaker could resolve the issue, and
2) If "cone cry" and "ghost notes" are the same thing.
Yes, very true. I believe the owner's name is John now...I'd have to dig through my emails. He seems like a solid guy by the 1 interaction I've had. I've gotten suggestions from them in the past of what COULD have been causing the issue. Speaker swap, as suggested seems like a good place to start.

Woundtight
05-10-2012, 10:55 PM
I have the same problem with my Bad Cat when playing a guitar with a humbucker in the neck. I get the most pronounced ghosting when playing my Willcutt DGT in the neck position. Yeah, you can lower the pickup height, but should the pickup really be below the mounting ring!? It still doesn't solve the problem... The other thing you did not mention is that most awful reedy, warbling sound you get when trying to fret a B note on the first string, 19th fret.
As I ask around, I believe the majority of the problem is due to the filtering on a cathode biased amp like a Vox ACxx, Bad Cat, Matchless, Morgan, etc. However, I have experienced it with certain Marshall and Fender amps. I have also been told its not really ghosting but it could be 'blocking distortion'...I don't know what that means really..
I think a single speaker exacerbates the situation, specifically a V30, for some reason. The moment you employ two speakers, or more, the problem is not as bad. It is still there, just not as bad.
One my techs, a Vox 'authority', said the original circuit design wasn't intended to be dimed or pushed to the edge and that some additional filtering might be required to prevent the problem from happening. So driving a 30 or 50W cathode biased amp into a single V30 ain't gonna work.
Bad Cat Hot Cat 15 into a single V30- pretty damn good design and match, it's my go to amp. Bad Cat Lynx (50W),Gain Channel into a 4X12 is killer. The Clean channel is unbelievable, but try to solo in the upper registers and that warbling just drives me @#@$% crazy. I asked Bad Cat to build me a Lynx 50W in a 1x12 combo with their V30 speaker. It was a disaster. I sent the amp back, I flew out to the shop with my Les Paul and DGT. He could not fix the problem with ghosting, warbling, howling, blocking distortion, whatever. I left with a killer Bad Cat CubX- 15W and 1X12.
Just last week I bought a Morgan AC20 Deluxe head and I got a matching 1X12 cab with a 100W Fane Alnico speaker. I'll be damned, that amp ghosts ( and warbles in the upper registers) more than my Bad Cats. That cabinet and speaker is awesome, the problem is clearly with the amp. I am sending it back to Joe, he's gonna try to fix it. Stay tuned, I'll let you know the outcome.

]-[ @ n $ 0 |v| a T !
05-11-2012, 10:19 AM
The other thing you did not mention is that most awful reedy, warbling sound you get when trying to fret a B note on the first string, 19th fret.
Awe man... I thought that was my strings getting old.

I, too, have read that this was a power transformer and/or filtering issue - which is why I asked EM7 to jump in. I figured there was a component that could be added, removed, and/or replaced in the circuit to resolve the issue.

Oi... one thing at a time. I am going to do replicate the problem, tomorrow, and replace the speaker (as suggested). I have several speaker/cab options that I can try. I'll report back with my findings.

]-[ @ n $ 0 |v| a T !
05-15-2012, 04:29 PM
Ok - did more looking into this. It appears as though "Cone Cry" and "Ghost Notes" are the same thing. I have updated the title of this thread to make it easier to find with a search.

There are MANY different opinions on this subject - as posted on the web. Some people claim that Cone Cry can be cured by flipping the speaker 180 degrees. Others claim you need to break in speaker(s) by blasting them for several days one end. Some people suggest the cab needs to be suspended and pointing down while doing that. Others, still, just add doping to the edges of the speaker cone and deal with the alteration in tone. But no one has posted (at least not that I have found) and a definitive and well documented "solution" to the problem.

If you're like me, dropping $100 or more for a new speaker when there may be other (cheaper) options, isn't an easy sell. Especially because new speakers can have the problem. Then what? There is no doubt that I need the cone-cry problem to go away. It's quite anoying. But I want to try some of these home remedies after I isolate the problem speaker and confirm (by swapping it out) that the issue is, in fact, the speaker (and not the amp).

More info as I have it.

LSchefman
05-15-2012, 04:57 PM
Hans, just out of curiosity, were you able to try disconnecting the internal speaker and connecting the amp to a different cab, to verify that it's in fact the speaker?

Let me know!

]-[ @ n $ 0 |v| a T !
05-15-2012, 05:04 PM
Hans, just out of curiosity, were you able to try disconnecting the internal speaker and connecting the amp to a different cab, to verify that it's in fact the speaker?

Let me know!
Not yet - but I will soon. Didn't get to it this weekend.

Audiowonderland
05-16-2012, 10:12 AM
Hey EM7,

How do I get rid of that @#$%^ ghost note problem in by Bad Cat TremCat 30 1X12 combo? The only way I can play the amp without hearing ghost notes is in 15 watt mode with a 1X12 extension cab added and the amp set at 4 ohms.

When I am running the amp with the single 12" speaker (no extension) at 8 ohms, the ghost notes are absolutely intolerable.

What am I calling a ghost note? The deliberate note I'm playing comes through loud and clear along with another "ghost" note at around 50% of the deliberate note's volume. The ghost note is a sour discord in a different key than the deliberate note - not at all similar or complimentary.

Hans, there's a fairly simple way to see if it's the amp's innards or a speaker, and that's to disconnect the internal speaker and run the extension cab by itself. Try the amp with the extension speaker in all of its modes. If it doesn't happen with the extension speaker, it's the speaker. If it also happens with the extension speaker, it's probably the amp, and it would be a good idea to send the chassis to Bad Cat for a look-see.

I had this problem with a Tremoverb, exactly as you describe. A speaker swap fixed it in my case.

Not necessarily. If they have the same speaker its possible that one speaker alone simply cannot handle the power of the amp. If you use two, they each receive only half the power which they may be able to handle.

Shawn@PRS
05-16-2012, 10:38 AM
No cone, no cry - Bob Marley

]-[ @ n $ 0 |v| a T !
05-20-2012, 02:41 PM
No cone, no cry - Bob Marley
But... I like cones.

]-[ @ n $ 0 |v| a T !
06-26-2012, 05:39 PM
More info on this topic... this info was passed to me by a fellow member. Em7, you out there? What's your take on this?

Many amplifiers are prone to "ghost notes." It helps to know what kind of amp we're talking about.

Certain capacitor brands, like F+T, LCR have high leakage current. Other capacitors for coupling have ESR problems, sometimes caused by the physical construction, and lead type. Pure copper leads reduce this, and tubular capacitors are less prone. This is because they do not have any flat sides for the signal to bounce off of.

Some amplifiers like F-type Black/Silverface models that have the ghost note issue can be reduced by cutting the phase inverter "output" coupling capacitor values in half.

Others generally are just suffering from old, or leaky filters. Vintage amplifiers like V-type AC30s have very low filtering, I believe this was not because of design, but more as an economical approach to save money. The same is true with many amplifiers designed in the 1950s. Increasing the filtering can cure the ghost note problem.

With M-type amps there are two ways to help cancel this out:
1) Install a luf 600-1000V non-polar plastic capacitor across the last decoupling electrolytic in the line. This is the last filter, which filters the supply for the preamp. The capacitor will be wired to "by-pass" this filter, one lead to ground, the other to the capacitor lead.
2) Increase the filtering. On 50 watt models, it seems to take another 50mf across the main B+, and another 50mf for the screen supply.

For 100 watt M amps, expect to add another 100-150mf across the main B+, and at least another 100mf for the screen supply. Now, the amp will be stiffer on bass notes, if not acceptable, you can add anywhere from a 100-200 ohm 209 watt resistor in series with the output transformer center tap, this will give back a looser feel.

Boogie
06-26-2012, 08:58 PM
That's a really interesting read but points to an inherent flaw in component call-out. Ultimately, it's a design flaw, regardless of manufacture. Ouch!

In a probably unrelated note, I've had a bit of ghosting or possibly post note resonance on my old Boogie recently. It drove me nuts. After tearing that amp apart and contemplated swapping what I thought was a bad EL34, I turned my screw driver toward the cabinet grill. Since I had recently swapped the old C90s for WGS stuff, the grill could have been over/under torqued back into place. Sure enough, after releasing and retightening all screws, the resonance disappeared. :s It cost me two fists-full of ripped out hair, but no $$.