what would cause HF rolloff in an audio circuit?

[Svart]

ok i've posted an mp3 of a song i'm currently working on. I've EQ'd this and compressed with GSSLs so you don't hear much of the problem I am talking about. nothing else was done

beyer M201 snare
SP B1's overheads
CAD cheapo Kick

guitar FET DI from ibanez floor pedals

no bass yet, no vocals yet, maybe more or less riffs, again this is just to get an idea where i'm at, I know guitars are a little loud and off center too. I'll post this in the brewery too since it really needs to be there.

http://www.geocities.com/noireclipse/Track01.mp3

let's see how long before geocities shuts it down.. :green:

 

[PRR]

> let's see how long before geocities shuts it down..

They didn't want to give it to me, one minute after your post. But I got it. Here's a mirror: Svart's Track01, 4 Meg MP3

Personally, I can't hear a thing in that wall-of-sound. Drums sound like filtered gated pink-noise, what I can hear in the whole moosh. Doncha have some clean drum riffs where we can hear what you are talking about?

 

[Svart]

hee hee, sure but i'll have to get them from the studio later this week.i don't know to take that as an insult or a compliment.. :green:

they got me for data transfer allocation violation.. i guess i'll be finding another host.

thanks PRR for the mirror!

:guinness:

EDIT: what I'll do is mixdown a non EQ'd version of the drums and a EQ'd to taste version if that will help.

 

[Svart]

OK..

I learned a valuable lesson from the advice of many of you here in this thread and others over the last week.

LESS IS MORE

suggestions from many of you urged me to rethink how i work and mix and here is what i came up with:

i went back and unpatched all my compression and effects and started with the raw track straight from the recorder( i only track the raw signals, no compression/effects until mixdown). I then noticed something interesting.. but we'll get to that later... I pulled the overheads up, then the bass drum, and finally the snare to fill in. I left the overheads as they were and patched compression to the snare/kick. sounded really good and actually much nicer.

now for the later part.. i figured out what was causing my mid range bump, however part of it is highly embarrasing

even though i tracked straight to the recorder and the tracks were raw straight from my mic pres, I always bussed the drums to one stereo buss. I always used compression on the drums to keep everything tidy.. I know you see where this is going..

having the overheads bussed through the compressor, even with little compression happening seemed to roll off their high end. (These compressors have polypro/FC caps. I took two of them and switched out the 5532s for opa2604s and the 5534s for opa627s. the problem gets worse with more compression unless I set the attack to the last two clicks(clockwise) which it then starts to get better. this tells me that the compression happening on the drums is killing the overheads, which i learned from advice and trial n' error, really doesn't need compression, or at least needs compression on it's own.

Truthfully i didn't really notice this problem until i started "upgrading my console and started to notice life beyond mud. upgrading caps didn't do as much as swapping opamps did. once i did that I noticed detail in the highs and detail in the lows that were once not noticed. once i started to get more fidelity i started to notice things that affect one another, however it was already habit to leave compression on the buss.

well hopefully someone besides me will learn something from this.. i've been chasing a ghost of a problem that never seemed to have a source until i tried new methods and figured it out by accident!

thanks to you all!

and don't be stupid like me!

 

[Svart]

actually I like the room mic! I didn't have time to play with it much but i'll be experimenting a lot. Actually i believe you were the one to mention compression causing the mids to overpower the highs weren't you Butta? I read what you said but it didn't click in my head until I found out by accident!

thanks!

 

[tmbg]

hey Svart, sorry I didnt get back with you Saturday... things got crazy and I had people around literally all weekend.

Glad you got that issue figured out At least your SSL didn't EXPLODE like mine did! :shock:

I got those caps replaced and made some XLR->TRS cables so it wont happen again.

 

[Svart]

sweet, I have 4 channels of forssell opto in the works too so that ought to be nice!

no worries TMBG. i read what happened to your ssl but i don't understand how that happened?? :?:

 

[tmbg]

I was using an ADA8000 as a A/D, running vocals through another preamp and into the SSL, then into the ADA mic inputs (cause I didnt have XLR to TRS cables), and phantom was on because I had other mics attached to the ADA, and apparently the phantom voltage reversed biased across the output caps caused them to pop.

 

[Svart]

yikes. at least those caps took the hit instead of something else. I wouldn't think that the phantom had enough amperage to explode those caps like that, unless they just overheated over time... ??

 

[tmbg]

yeah, it must have been over time, cause I've used the thing for awhile, and we had it hooked up running continuously all night, and it finally popped at like 2am.