Wolf notes and feedback

[kedo]

Hi, I have posted on this topic before on this forum , but have not yet resolved my problem.

I have a Stentor 'Elysia' DB with a Shadow SH950 pickup and play through a Markbass CMD 121P combo with 121 New York extension speaker. My problem is terrible 'booming' and 'swelling ' on notes, specifically on the G string (only when amplified). I have noticed that when I play on the G string whilst damping the other 3, it improves. The sound is like a 'strobe' so maybe it's a phase issue, but I'm not really sure what that means. Members have advised me to get a Fishman 'Platinum Pro' bass preamp which I would buy if I thought it would improve the situation, but would prefer not to have to use electronics if possible.

I have tried the following with limited success:
Removing the extension cabinet. This improves the situation slightly but I lose power obviously, and the sound is too thin for me, especially in larger venues.
Flattening all the preamp controls. This helps but the sound again is thin.
Positioning the amp away from the DB and walls etc. This has probably resulted in the most profound improvement, but every venu is different.
Dampening the after-strings and blocking the 'F' holes doesn't do much, but having someone to hold the bridge tightly on the treble side improves things. I can't think how I could simulate this in practice.
Separating the amp and cab. This doesn't help much.
Removing one side of the pickup helps, but unbalances the volume from string to string.
I am in contact with a good tech who specialises in DBs. He thinks he could help by maybe moving the sound post and other stuff, but he's not well at present.

I played acoustic DB for years without amplification and didn't realise that this is such an issue. Maybe I have the wrong pickup. Perhaps one which sits under the feet of the bridge would be better than the Shadow which fits into the scrolls. Any ideas would be extremely welcome.

[Bilbo]

You need a phase switch like the one on the Fishman. They also have them on Acoustic Image mics. I have no real idea how they work but they stop the problem you are describing, which is actually very common. You can usually pick up a Fishman for less than £100.

[TPJ]

The Art Tube MP also has a phase switch. It's more of a mic preamp with no eq but it works well with DB. Much cheaper 2nd hand too.