Author Topic: crackling during guitar parts! wtf! (Read 4917 times)

zhianosatch · « **on:** January 16, 2005, 06:00:31 PM »

hey, all. wondering if i'm fucked.
i blamed the extremely faint, distant, non-musical crackling during the guitar-heavy parts of one slayer and two manson shows on a pair of radio shack RCAs. schoeps mk4s > rmod box > my modsbm-1 > my d8. i'll try to post samples soon. Alex told me i was high when i told him about the problem as we listened together, but, alas, i was more than sober.
now, after recording a local show last night with my rig (dpa 4061s > modmps-6010 > modsbm-1 > d8), i hear the same crackling, but only during the guitar parts again!
my levels in all cases were hovering certainly below 0 and i can hear the crackling during a guitar fade-ins and -outs when the overall levels are far below 0. this problem has now happened with two rigs, so the problem has to be either:

-modsbm-1
-d8
-playback

-modsbm-1

i have no idea what could be wrong with it.

-d8

i ran a cleaning tape before the three-show slayer/2x manson run and immediately before last night's show. any other ideas?

-playback

i'd be happy to blame the problem on plaback problems, but nothing adds up! why would the crackling only be audible during guitar parts? could three vastly different PA systems (slayer/manson/local dive) have the same flaw? shoot, last night, the guitars weren't even run through the PA, just their amps.
i'm using either:

waveterminal 2496 (set to either -10 dBu or +4 dBv, with varying ouput gain) > canare interconnects > denon avr-1603 > canare speaker cable > b&w dm302s
waveterminal 2496 (set to either -10 dBu or +4 dBv, with varying ouput gain) > canare interconnects > denon avr-1603 > sony mdr-7506s
alex's home setup
old-ass rotel cd player > rotel amp > linn keilidhs (crackling lessened or eliminated)
d8 > sony mdr-7506s (crackling lessened or eliminated)

why in the world would i only get crackling during guitar parts only?
argh, i don't want all future shows ruined! any ideas?
armen

macdaddy · « **Reply #1 on:** January 16, 2005, 09:36:15 PM »

could it be coming from the PA - were these all recorded at the same gig/PA..?

were you running levels hot? (remember my theory on headroom

)

post some samples, amigo - i will give a listen for ya

edit:

ok so if it is the sbm1, it might be the rca males you have are too loose..? twisting can sometimes result in crackles...

have you listened to the dats played back on a different deck/system..? that would answer your question about palyback...

nickgregory · « **Reply #2 on:** January 16, 2005, 10:17:44 PM »

definitely post samples....I had a case when I thought I heard something strange coming from my rig, but when I compared it to Scott Browns tape (who was there also...well obviously if he had a tape), I heard the same thing...turned out something a little funky happened in the PA I did not remember...this could be a case of that...especially with a manson show...you were probably on sensory overload and I would not be surprised if you missed something

zhianosatch · « **Reply #3 on:** January 16, 2005, 10:30:18 PM »

samples on the way...
i just can't believe that i'd hear the exact same sound at four different shows. i listened with and without ear plugs at different points in each show and heard nothing like it from the pa, but we'll see.
p.s. manson this time around was impeccable. incredible show. i eargasmed out of my mind during "the fight song" in LA.

zhianosatch · « **Reply #4 on:** January 16, 2005, 11:00:09 PM »

http://www.calpoly.edu/~amenendi

try those, then i'll UL some more. let me know when you're done fetchin'.

Brian · « **Reply #5 on:** January 16, 2005, 11:27:03 PM »

i've listened to each twice and i can't hear what you are talking about. sounds perfectly fine to me.

i'll listen again, but my ears aren't hearing anything. i'm tired though so i could not be hearing right at this point in time.

edit: maybe your playback system can't handle those high-mid range frequencies due to a blown tweeter? just pray it's anything BUT physical damage to your ears. I know an engineer here in St. Louis that exclusively works with metal bands. if he moniters too loud the 6-10k freequencies start "crackling" because of hearing damage from those powerful guitars on a regular basis. but if you have always been using earplugs you should be fine. not trying to scare you or anything.

Brian · « **Reply #6 on:** January 16, 2005, 11:46:04 PM »

damn. tinnitis is a BITCH! one of my teachers, Bill Porter(engineered elvis, roy orbison, the everly brothers), can;t hear past 8k because he was a pilot

i consider myself lucky that i can still hear up to 19k! i still forget my earplugs waaaayyyyy too much. i need to keep a box of them in the car

Brian Skalinder · « **Reply #7 on:** January 16, 2005, 11:59:44 PM »

I definitely hear the crackling your reference, Armen (no, your brain is not turning to jello - at least not yet!). Easier to hear on clip 1 than 2, though I hear it through most of 2 as well, just not as pronounced with the percussion covering it up.

As to what it is...I haven't the foggiest idea. When my modSBM-1 op amps starting biting the dust, it resulted in a slight squaring off of the wavform well below 0dB - but the audible result more fuzz than crackling.

Can you replicate the problem at home?

Crank up a known non-crackly recording on your playback. If the playback is the culprit, you'll hear the crackle. If it isn't, then try to replicate the problem. If you can replicate it, take the modSBM-1 out of the mix. Obviously, if the crackle goes away, the modSBM-1 is the culprit. If it doesn't, then...well, I'd say swap out the D8, but you're feeding it a digital signal so I'm not sure why the D8 would be the culprit.

Brian · « **Reply #8 on:** January 17, 2005, 12:01:52 AM »

damn my ears.....i'm going back to listen again

Brian · « **Reply #9 on:** January 17, 2005, 12:05:59 AM »

i just wasn't listening loud enough. i can definitely hear it now too. definitely some harmonic distortion/crackling going on with the guitars. the guitars are the loudest instruments so i can't tell if it was the PA or your recording.

zhianosatch · « **Reply #10 on:** January 17, 2005, 12:46:34 AM »

ok, lemme take those down and put up the others.
thanks for all o' your help!
p.s. brian, i've tried the known-good recording scheme and neither the B&Ws nor the mdr-7506s crackle, except with those new albums that i KNOW are truly clipped!
i'll try it when i get home, but i don't think i have playback loud enough to give the modsbm a loud enough source. then again, i might be talking out of my ass; i haven't tried it yet. i will do asap.

zhianosatch · « **Reply #11 on:** January 17, 2005, 12:49:32 AM »

ok, try those new manson phlacs. another manson and one slayer are up next.
i'll post mp3s instead if you want.
p.s. once you hear the whole version of manson 12-20, you'll know why this problem breaks my heart! what an incredible tape! god damn it!
p.p.s. you can also hear the cracklin' during audience-only parts of manson 12-20, and it's not applause.

KingReptile · « **Reply #12 on:** January 17, 2005, 01:04:19 AM »

I cant wait to hear the whole thing ,my ears must be screwd will have to crank it up tommorow sounds dam good 11 secs wasnt enough

zhianosatch · « **Reply #13 on:** January 17, 2005, 01:10:20 AM »

yeah, and the other one is infinitely better, man. :-/

F.O.Bean · « **Reply #14 on:** January 17, 2005, 09:04:01 PM »

Quote from: Moke on January 17, 2005, 08:45:22 PM

Here is a + for you Alex.

Armen,

Were your power supplies up to snuff? low power can cause weird issues. just a thought. I haven't been following this thread real closely, so,.... if this has been covered, never mind.

thats def a possibility mok3st3r, also, maybe dat related?

record a test at home and see if the crackles are in there, maybe its bad heads

F.O.Bean · « **Reply #15 on:** January 17, 2005, 09:09:21 PM »

sounds maybe like a power/clipping issue

macdaddy · « **Reply #16 on:** January 18, 2005, 10:04:47 AM »

Quote from: Bean on January 17, 2005, 09:09:21 PM

sounds maybe like a power/clipping issue

qft

armen - try running your cd player rca outs into the sbm1 > dat... see what happens . just use a disc that you know has no crackling issues of its own...

zhianosatch · « **Reply #17 on:** January 18, 2005, 11:30:49 AM »

good calls. thanks for your help, everyone. a lot.
moke - both d8 and sbm were powered by lenmar 2450 mAH AAs and the occasional set of alkalines.
mark - my cd player's RCA outs are fucked. i'll find another source.

macdaddy · « **Reply #18 on:** January 18, 2005, 11:53:39 AM »

Quote

my cd player's RCA outs are fucked. i'll find another source.

ok - the how about a tape output (cassette). anything other than a phono out (which typically requires a preamp stage) will send a signal loud enough for you to test the sbm1...

zhianosatch · « **Reply #19 on:** January 18, 2005, 02:05:16 PM »

Quote from: macdaddy on January 18, 2005, 11:53:39 AM

Quote
my cd player's RCA outs are fucked. i'll find another source.

ok - the how about a tape output (cassette). anything other than a phono out (which typically requires a preamp stage) will send a signal loud enough for you to test the sbm1...

right-o. i just felt like telling y'all that my cd player is fucked up.

wboswell · « **Reply #20 on:** January 18, 2005, 02:20:03 PM »

I've had some similar issues recently: The right channel is producing an audible HF hum. The high pitched hum is only in the right channel and not in the left. I was told to clean the active cables but I'm not sure what's the best way... any suggestions?

macdaddy · « **Reply #21 on:** January 18, 2005, 05:32:14 PM »

to this end - i had problems with the miniplug that came with the HEB mics (which is why i had leegeddy mod the cables, so now i have dual rca male terminated cables coming out of the miniXLR...

my point is - do not rule out the cables as the source of your problems...