Author Topic: D100/M1 brickwalling problem (Read 8165 times)

Sean Gallemore · « **on:** March 15, 2004, 06:34:09 AM »

I'm under the impression that my recording shouldn't look like this.
Very disappointing...

AT853Rx > mp-2 > m1

not sure what could be going wrong. Armen got the same thing at Ras Michael with the mp-2, though not as bad, which isolates the mp-2 as the culprit. Thoughts?

thanx
~schwill

BCostigan · « **Reply #1 on:** March 15, 2004, 07:02:01 AM »

No clue what could be happening but that is a weird looking wave. $:-\$

Sean Gallemore · « **Reply #2 on:** March 15, 2004, 07:05:22 AM »

I'm told it is "brickwalling," but why/how is it happening with my mp-2?

Sean Gallemore · « **Reply #3 on:** March 15, 2004, 07:11:11 AM »

dfhgjkadfhgkl;jhadfkjgxcb nmadfhgkhvkjxfnh!!!!

BCostigan · « **Reply #4 on:** March 15, 2004, 07:20:20 AM »

I don't understand why it would be brickwalling. To me it looks like some kind of power issue because the wave form is cycleing.

I'm sure someone more qualified will be along shortly to help out!

sickrick43 · « **Reply #5 on:** March 15, 2004, 07:26:29 AM »

Could be brickwalling because the top of the waveform is squared off (clipping) but the other noise is weird. I'd look at power/cabling first.

SPL did not exceed the rating of the microphone, did it? Too loud an input signal would saturate the front end of the mic, and cause brickwalling at that stage (hence attenuators on mics).

Does this happen consistantly, or was this a one time, non-duplicatable, freak occurance Schwilly (and did you wash those SHEETS yet?)

Rick

Sean Gallemore · « **Reply #6 on:** March 15, 2004, 07:37:15 AM »

Quote

but the other noise is weird

what other noise?

This was during metallica tonight (last night).

Happened consistantly throughout the show.

Mics powered 48V. Never had a problem in the past. (well, I haven't)

the bass might be overloading the mics, but I don't think that is the problem because this happened last week with different mics at a much more mellow show.

Anyone heard of an mp-2 brickwalling?

I just need some sleep

muj · « **Reply #7 on:** March 15, 2004, 07:40:08 AM »

might be the transformers on the input,dying..and can not handle as much input signal any longer.

Sean Gallemore · « **Reply #8 on:** March 15, 2004, 07:42:53 AM »

hmm, seems very possible.
first, I want to thank everyone for responding so quickly, big + all around

second, I'm gonna contact SD and get their thoughts, see what they can do.

zhianosatch · « **Reply #9 on:** March 15, 2004, 07:47:58 AM »

I don't know, man - something is certainly fucked.
For Ras Michael, I ran DPA 4061s > modMPS-6010 (no HPF) > MP-2 (HPF @ "80") > M1 and there was definitely some brickwalling action, just like the HPF wasn't working and there was too much low end for the MP-2 to handle. I thought it'd be an isolated incident... but now, I'm starting to think that something might be wrong with the MP-2. But what?
asdfjkjkldfakldfjasldkfjlsdfkj is right.
A

muj · « **Reply #10 on:** March 15, 2004, 07:48:30 AM »

i know it's frustrating..trust me.

zhianosatch · « **Reply #11 on:** March 15, 2004, 07:53:25 AM »

I had to deal with this shit all the time with my 4061s and AD-20, sometimes even after I padded the inputs... this has to be fixable!

1st set only · « **Reply #12 on:** March 15, 2004, 09:00:04 AM »

how bad does this sound? Looks like an interesting problem, hope you get it figured out. when I just glanced at the wav i first thought DC offset but nope.... hmmmm

hoobash · « **Reply #13 on:** March 15, 2004, 09:47:38 AM »

How offen where the red overload lights going on???

MattD · « **Reply #14 on:** March 15, 2004, 09:48:11 AM »

I can't read the pic well enough, but what is the frequency of the largest waveform (the one all the others are riding on)?

zhianosatch · « **Reply #15 on:** March 15, 2004, 09:53:05 AM »

The MP-2's meters were off, I'd imagine, at Metallica. The M1 levels never hit 0, though.

MattD · « **Reply #16 on:** March 15, 2004, 09:57:38 AM »

Armen, that description sounds like the limiter was on. Perhaps it was set too low and limited just about everything it was passing? The MP-2's (or any) limiter makes it possible for you to take a signal however hot and still not clip the deck. It's a GREAT thing for stealthing if it kicks in only once in a while.

zhianosatch · « **Reply #17 on:** March 15, 2004, 10:11:54 AM »

Matt,
Good point. I don't want to second-guess myself, but I could have sworn that I had everything off when I ran it, including the limiter. Maybe the switch is fucked up? We'll ask Schwill when he wakes up.

nickgregory · « **Reply #18 on:** March 15, 2004, 11:05:49 AM »

those mp-2 switches can get switched sometimes and you dont notice it til too late. Mine got switched to phantom off the other night and it took me 15 minutes to figure what caused the problem...but yes it sounds like a limiter issue...

L Ron Hoover · « **Reply #19 on:** March 15, 2004, 02:17:24 PM »

I'm thinking limiter as well all though I've never used mine.
Fortunatley those little switches have stayed put on my MP2.

Sean Gallemore · « **Reply #20 on:** March 15, 2004, 02:43:50 PM »

the limiter wasn't on, or atleast the switch wasn't on. Maybe the switch is broken?

Yes, that is a picture of the bass with other frequencies on it. You can see how it is being clipped in a sloping fashion, not straight across like a clip would. They are definitely not clips from the M1

scb · « **Reply #21 on:** March 15, 2004, 03:07:24 PM »

what does it sound like?

Sean Gallemore · « **Reply #22 on:** March 15, 2004, 03:18:56 PM »

it sounds like brickwall. This noise isn't riding on the bass. I cut the bass all the way from 225 down and it's still there. I isolate the bass and the sound is not there.

here's a zoomed in shot AFTER I CUT the bass away. The weird shit is still there visually and audibly.

scb · « **Reply #23 on:** March 15, 2004, 03:45:49 PM »

can the 853s you have handle a full 48 volts?

Sean Gallemore · « **Reply #24 on:** March 15, 2004, 03:53:42 PM »

they have the power adapters on them, specs say they can take 9-52V with them. I've used 48V with pristine results in the past.

thanx again all

scb · « **Reply #25 on:** March 15, 2004, 04:04:27 PM »

are they putting out a hot signal to the mp2?

Sean Gallemore · « **Reply #26 on:** March 15, 2004, 06:44:39 PM »

dunno, is this hot?

MattD · « **Reply #27 on:** March 15, 2004, 06:47:16 PM »

7 mV/Pa is pretty standard for non-high sensitivity mics.

Sean Gallemore · « **Reply #28 on:** March 15, 2004, 06:56:48 PM »

like I said, I've been problem free save for the mp-2's last 2 outings.

Sean Gallemore · « **Reply #29 on:** March 15, 2004, 10:27:37 PM »

fwiw, it's on the godsmack tape too, but to a lesser degree. Maybe it gets worse throughout the night implying that something is dying?

in fact, I just checked the end of the Metalica tape and it is worse than the beginning, which is worse than Godsmack...

muj · « **Reply #30 on:** March 16, 2004, 01:06:52 AM »

post mp3 or wav file please

Sean Gallemore · « **Reply #31 on:** March 16, 2004, 02:40:28 AM »

F.O.Bean · « **Reply #32 on:** March 16, 2004, 09:20:06 AM »

since i dont have high speed schwill, i cannot listen, but good luck in yer taping adventures and everything will pan out

maybe a bass filter issue w/ the mp-2, THAT was engaged at all shows too right??

Sean Gallemore · « **Reply #33 on:** March 16, 2004, 10:22:23 AM »

no bass filter for me.

Armen used it at Ras Michael with the DPAs, and we thoguht that might be the problem. Appearantly not

nickgregory · « **Reply #34 on:** March 16, 2004, 10:29:46 AM »

run it in front of your stereo and see if you can recreate it....I will listen to the clip tonight, but it may not hurt to see if it is a constant problem or just a loud SPL problem

muj · « **Reply #35 on:** March 16, 2004, 12:17:29 PM »

can't play the file..damn!

Sean Gallemore · « **Reply #36 on:** April 01, 2004, 03:33:49 PM »

"I have an M1, but it's basically the same deal.. if you set the trim knob lower than 4 it will overload the preamp (line-in will do the same) and the peaks in your recording will sound very distorted... almost fuzzy. if you go over to the old oade board and search on brickwall i'm sure there's a lot more information.... "

got this in an IM from cooker! Sounds exactly what happened to me, especially since I was at a loud concert and the gain on the mp-2 had been higher than I normally have it. Just thought I'd share this update and information.

Todd R · « **Reply #37 on:** April 01, 2004, 04:19:46 PM »

I'm still not sure Kyle is right on this one. See my post in this thread:

http://www.taperssection.com/yabbse/index.php?board=23;action=display;threadid=16458;start=15

I'd like to have some verification of brickwalling problems into a D100/M1 when run line-in. Especially when run line-in that doesn't involve the use of an MV100 which I know from experience has its own issues with brickwalling.

I'm not saying that an M1/D100 can't be having problems with brickwalling. But I never had issues with my D100 brickwalling when run line-in, and I did have problems with the MV100 brickwalling, which I solved by modifying the MV100.

Cooker · « **Reply #38 on:** April 01, 2004, 06:18:50 PM »

i have two shows with brickwall issues running line in to the M1 without my MV-100 in the chain. one was NMAS where i patched out of Justin Carlson's KM184>V3, and another was when i patched out of a 4011>V2>AD2K >DA-P1 rig (not sure of which show that was - maybe Galactic)
i may still have one of the NMAS tapes handy, i know i recorded over one of 'em for the Bridge.... if so i will transfer a sample.

leegeddy · « **Reply #39 on:** April 01, 2004, 10:15:57 PM »

Quote from: cooker on April 01, 2004, 06:18:50 PM

i have two shows with brickwall issues running line in to the M1 without my MV-100 in the chain. one was NMAS where i patched out of Justin Carlson's KM184>V3, and another was when i patched out of a 4011>V2>AD2K >DA-P1 rig (not sure of which show that was - maybe Galactic)
i may still have one of the NMAS tapes handy, i know i recorded over one of 'em for the Bridge.... if so i will transfer a sample.

>>one was NMAS where i patched out of Justin Carlson's KM184>V3,
>>4011>V2>AD2K >DA-P1 rig

a quick ? for ya: why (and where) would a MV-100 be in these signal chains?

are you saying that you were amplifying the patch signals through your MV-100? that may explain the brickwalling. you'll be sending a very hot signal to your M1.

marc

zhianosatch · « **Reply #40 on:** April 01, 2004, 10:36:24 PM »

BOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOM

Sean Gallemore · « **Reply #41 on:** April 02, 2004, 12:21:32 AM »

marc, he said "without the mv-100 in the chain"

leegeddy · « **Reply #42 on:** April 02, 2004, 12:29:37 AM »

Quote from: Schwillster on April 02, 2004, 12:21:32 AM

marc, he said "without the mv-100 in the chain"

oppps. can't read tonight. thanks, schwillster.

marc

Sean Gallemore · « **Reply #43 on:** April 02, 2004, 12:41:58 AM »

Quote from: leegeddy on April 02, 2004, 12:29:37 AM

Quote from: Schwillster on April 02, 2004, 12:21:32 AM
marc, he said "without the mv-100 in the chain"

oppps. can't read tonight. thanks, schwillster.

marc

no problem, I'd like to get this issue solved for sure. The only way I'll truely know is to run it in the field. Thanx for everyone's input, once again.