Double Bass HELP! I HAVE SOME PROBLEMS WITH MY AMT SP25B MIC!

[pao_bass]

By the way, I use the AMT mic solely without any accompanying pickup. But of now, i'm really having some problems with my recently purchased SP25B microphone... first, the gooseneck has a tendency to move (it moves very easily out of its desired position) towards the bridge too much up to the point of really touching the bridge which results in a very undesirable growl. second and more importantly, I'm having some problems with excessive, really annoying feedback (I'm using the 1/4 line driver switched to the amp, and then the XLR input of the super preamp for the house). As a result, I can't reach my desired volume in order to cut through through the sound of the band. Is this common among AMT mics? Everytime I turn up the volume, There is a very loud feedback. Why is this so? It keeps on coming back even if I turn the amplifier behind me away from my direction.

Another problem also is when i turn up the volume, I also get too much reverb. the sound just sometimes fails to decay.


Right now, I'm getting a bit frustrated and I'm thinking of buying a david gage realist and use it as my pickup instead. Is there a solution for my present situation? or do I really need to replace it with a transducer? please help! I will be greatful for any response, opinions. Thanks and good day to you all. [/B]

 

[bolo]

pao_bass, as far as the gooseneck drooping out of position, I would start by making sure the clamp on the side of your bass is tightened securely.

The gooseneck also seems to hold its shape better if it has a mild bend and/or twist in it. You may have to adjust the position of the clamp on the side of your bass to get the head of the mic back where you want it.

What kind of feedback are you getting? The whining electronic kind, or the boomy bass kind?

When you say "reverb", do you have the mic near the f-hole perhaps? That location can be somewhat boomy.

Do you have any prior experience w/ other mics or pickups/transducers that you could elaborate on, particularly if it seemed to work well for you?

Sorry for anwering some of your questions w/ more questions.

 

[pao_bass]

i actually get two kinds of feedback. When I turn up the volume knob from the preamp, I get the whining kind. When I turn up the volume knob of the amplifier, I get the boomy bass kind.


I position the gooseneck in a place right above the left foot of the bridge with the bass in front of me facing the audience. Is that an Ideal location? Before, I used to place the gooseneck very near the left f-hole.

Prior to this, I've only had experience using a boomstand mic with my DB. I've never had the chance to use another kind of transducer with a real DB. I've only had an experience with a transducer but it's with a stick EUB kind. (another story)

What is your opinion on transducers? do I need a transducer for my situation? or do you think I can get by using the AMT solely?

 

[Chris Fitzgerald]

I think that most mics are best coupled with a pickup for live sound purposes that involve a drummer. I almost always use a combination of a mic and a pickup. The mic gives the sound the "warmth" and "air", but will often sound a bit hollow in terms of cutting through the mix. The pickup gives the sound its center, and if you've taken care of some details and the acoustics aren't too bad where you're playing, the idea is that the sound of the pickup will be disguised and enveloped by the sound of the mic. A couple of things I do when using a mic:

1) Raise the amp up over the body of the bass. This gets the amplified sound out of the direct line with both the mic itself and the body of the bass. This can be done a variety of ways, but here's two pictures of my solution:

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2) Position the mic in a place that doesn't get too boomy - I put mine between the bridge feet, as the sound near the f-holes creates feedback much earlier than the sound at the middle of the top.

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3) Mute the afterlength of the strings when playing at or above moderate volumes. I use foam for this, but anything that absorbs the vibration of the afterlength will do:

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Last, experiment often and take notes. Good luck!

 

[bolo]

Echo everything Chris said. All of it. (Or +1 if you're more math oriented).

Here's my view - If you have been playing upright a while and can generate plenty of volume acoustically, then the mic only solution might be fine. But I tend to rely on a pickup too like Chris described. Big rooms full of noisy unattentive people is the main reason I blend a p/u w/ a mic, or sometimes just use the pickup.

FWIW, this creates a contradiction of sorts for me. The mic sounds best when I really dig in and try to generate a big acoustic sound. But when I do that, my pickup just seems to get "overloaded" in a sense, and starts to sound pretty harsh and overexcited. The pickup sounds best (to me) when I really lay back and use a much more gentle, sweet right hand approach. But that in turn means I'm not generating a lot of oomph from the bass acoustically, and the mic signal gets weak ... Make any sense?

I never practice with an amp, unless I've got a brand new piece of gear. So I strive for a big acoustic tone. Great for the mic. But then on a gig, the pickup sounds less than ideal when I do this, so I back off with my right hand. Recently I realized I'm actually using two different techniques - one for acoustic tone when I practice, and a different one on gigs for amplified pickup tone (much lighter - let the p/u and the amp do the work).

I guess this is a long way of saying you gotta find what works for you, given your preferences, gear, playing situations, instrument, and ability. If you play in without a PA in high volume situations or rooms that are rather large, you may want to consider looking at pickups at some point.

If you find a p/u that works for you, you can always blend it w/ your mic, and favor one or the other depending on the situation.

P.S. If you send me an email, I will email you back a Word document with a whole bunch of different people's takes on mic placement.

P.S.S. In addition to adjusting where you stand relative to your amp, you may have to fiddle with the EQ on your amp to tame the whining high-pitched electronic feedback. I've found that the mid (not the treble) EQ band on my Solstice is very effective at taming this kind of feedback.