Topic: Brickwall? Overload? Bad 9V?

[greenone]

Hey all - went to stealth Guster/Ben Folds/Rufus Wainwright last night in NH. Stealth rig is SP-BMC-6 (the AT803b's)>SP battery box>D8. My first time stealthing (or using that rig) in a while, and listening to it this afternoon, it sounds "blatty", like a broken cone on a speaker (which it's not - other shows sound fine). At first I thought it might be brickwalling because I had my levels at around 4 or 5, but then I realized I was running line in...it's not possible to brickwall on line in, right, because there's no preamp to overload?

Then I thought maybe I was over the rated SPL for the mics, but I was at the back of the first section, dead center, not with my head in the stacks, and it's not like these guys play particularly loud music. I checked my levels on the transferred file and some of the peaks are hitting close to 0, but even some that don't go that high still have the same sound. I also used these mics from late 2002 through early 2003 and for the occasional stealth job late last year with zero problems.

Any ideas what could be going wrong? I'm thinking *maybe* the 9V battery in the box is running out, but I've got another show next week and don't want to screw another one up if that's not the case... Thanks for any help!

--Dave

[nickgregory]

this is the same problem I had with those mics.  I dont think it is necessarily volume that causes the distortion, but more of the frequency of the sound.  For a show like Springsteen, the tape turned out great, except for a tiny bit of distortion on the opening for Born in the USA, for the Peppers or Kid Rock, it seemed every bass drum pop or bass string caused distortion....

Since I have gotten the 853Rx's and power them with a full 48 Volts, I have not had any problems...leading to my belief that is must be the mics...

ymmv, but that is my experience....

[greenone]

Thanks, Nick. I should mention that the lion's share of the tapes made with these mics is also Guster, when they play non-taper-friendly gigs. So I've successfully taped the same band playing the same songs before and not run into problems - both on a stand and in hat/lapels. I may try replacing the 9V and if that doesn't work, perhaps an upgrade is in order. But isn't it always...

[Sean Gallemore]

does the wav look like this?

[greenone]

I didn't get a chance to zoom in that close yet...I'll see if I can grab a screenshot tonight...

[Sean Gallemore]

well, it'll probably be milder than that

[jk labs]

do you have multi-meter? handy taper tool.

get a new battery, and give it a go. check the voltage of the new battery, and log it for later comparison.

And, for educational purposes (:-)): check the voltage on the battery you are removing
while this battery is under load (i.e. measure the voltage across the battery terminals with
the mics connected and after the voltage has become stable). And be sure to post the results!

I don't know these mics first hand but if they do struggle when powered with a slightly
discharged 9V battery you could do two things to counteract:
a) switch to a 9.6V rechargeable 
b) reduce the two gain resistors inside the batterybox (=more voltage on the caps
but obs! less output signal as well).

Jon
it's possible to qyou have two quick to implement
remedies. f voltage is a 

[dklein]

do you have multi-meter?.

9v batteries - do you have a tongue? 

Whaddya think Jon - is saliva sufficient load? 

[Sean Gallemore]

buzzzzzz!

[jk labs]

do you have multi-meter?.

9v batteries - do you have a tongue? 

Whaddya think Jon - is saliva sufficient load? 

No gold fillings? :-)

 - J


 -- J 

[greenone]

I don't have a multi-meter but I may pick one up. Never worked with one before...or at least, not since college sophomore physics. Anything in particular I should look for?

In the meantime I grabbed a new 9v, we'll see if that works.

--Dave

[Humbug]

Could somebody confirm - this is brickwalling, right?

[Sean Gallemore]

depends

[AT853rxwh]

depends

Those are diapers for adults

[Sean Gallemore]

well, it could be a lot of things

could be brickwall, could be hyper-compression from FOH, could be post-production compression. could be...