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Gear / Technical Help => Ask The Tapers => Topic started by: Datfly on October 10, 2008, 09:31:10 AM

Title: Why did my recording fail ?
Post by: Datfly on October 10, 2008, 09:31:10 AM
Last night I tested my new set up.
I recorded Stained at the Hard Rock.
I was in line with the stack and sound was clear.
I was near the back of the Hard Rock on the second level.

According to my levels I was not peaking at all.
I kept the levels just below the peak range ( beteween 12 & 6 )

My problem was distortion.
Any bass at all is just simply distorted.
Even the louder parts have a brickwalled sound to them.
The edirol was on my lap and I checked it several times
and ( again ) it did not peak at all !?
I made SURE I was line in.

Ideas ? Sugestions ? Thoughts ?

Set up

DPA-4021 > Aerco MP-2 > Edirol R-09HR

R-09HR Line In to Aerco > Input Level on R-09 set at 70 to get to 12 & 6 on front screen

Aerco +20 on the dials

R-09 Limiter OFF
Plug in Power OFF
Low Cut OFF

Mic Gain HIGH

My only thought is becuase I did not see that Mic Gain was switched to high
it caused the distortion?

Title: Re: Why did my recording fail ?
Post by: Belexes on October 10, 2008, 09:47:46 AM
My guess would be that the mic gain switch should have been on low.
Title: Re: Why did my recording fail ?
Post by: T.J. on October 10, 2008, 09:52:32 AM
My guess would be that the mic gain switch should have been on low.

yup
Title: Re: Why did my recording fail ?
Post by: Belexes on October 10, 2008, 10:13:11 AM
Especially with +20 dB on the Aerco.
Title: Re: Why did my recording fail ?
Post by: Dede2002 on October 10, 2008, 10:42:23 AM
Last night I tested my new set up.
I recorded Stained at the Hard Rock.
I was in line with the stack and sound was clear.
I was near the back of the Hard Rock on the second level.

According to my levels I was not peaking at all.
I kept the levels just below the peak range ( beteween 12 & 6 )

My problem was distortion.
Any bass at all is just simply distorted.
Even the louder parts have a brickwalled sound to them.
The edirol was on my lap and I checked it several times
and ( again ) it did not peak at all !?
I made SURE I was line in.

Ideas ? Sugestions ? Thoughts ?

Set up

DPA-4021 > Aerco MP-2 > Edirol R-09HR

R-09HR Line In to Aerco > Input Level on R-09 set at 70 to get to 12 & 6 on front screen

Aerco +20 on the dials

R-09 Limiter OFF
Plug in Power OFF
Low Cut OFF

Mic Gain HIGH

My only thought is becuase I did not see that Mic Gain was switched to high
it caused the distortion?



Hi there,

The Mic Gain switch has no effect at all when you run Line In. It only works with the Mic input.
Anyway, I find it really strange that you set your R-09HR at 70. Specially when you run a preamp before it. I assume the Aerco is a pre. Well, I´ve never went that high with my R-09HR. If I remember correctly, once I set my unit at 65 when that was a 100% acoustic gig and no preamp. When I run my 9100 preamp,  I have to stay in the 40's region on my R-09HR otherwise the recording will clip. And I always set my levels peaking between -20db and -12db. With 24 bit, there's no reason to tape hotter than that.
My 0.00000002 cents.
There got be another thing going wrong with your rig.
Title: Re: Why did my recording fail ?
Post by: Datfly on October 10, 2008, 10:44:39 AM
I needed this to get the levels up in the first place....... ?

If My mic gain was set to low ( I thought it was )
I might have needed more ifrom the Aerco if the gain on the R-09 was on low as I had the levels button
set to 70 to get the levels up.



Especially with +20 dB on the Aerco.
Title: Re: Why did my recording fail ?
Post by: Dede2002 on October 10, 2008, 11:00:23 AM
I needed this to get the levels up in the first place....... ?

If My mic gain was set to low ( I thought it was )
I might have needed more ifrom the Aerco if the gain on the R-09 was on low as I had the levels button
set to 70 to get the levels up.



Especially with +20 dB on the Aerco.

+20db from your preamp? That´s a lot. I´m not familiar with the band you taped, if it´s loud or not. Anyway, if you were feeding your Line input with a +20db load, the R-09HR should be set up at much, much, much lower rec levels to avoid clipping. The strange thing is that you say your levels were OK. Just to give you an idea, whith my preamp at +10db, I have to set my R-09HR's rec levels at 40 maximum ( for medium loud concerts).
Odd  :hmmm:
Title: Re: Why did my recording fail ?
Post by: Belexes on October 10, 2008, 11:10:34 AM
I had a similar sitatuation at a loud TOOL concert. Had the ST-9100 at +20 dB and levels on my M1 were at -6 dB and it clipped like crazy. It was overload from the mics > pre and the recorder was fine.  I should have set the gain on my pre much lower.

Does the Aerco have an LED or any indicator to show clipping?
Title: Re: Why did my recording fail ?
Post by: edtyre on October 10, 2008, 12:23:34 PM
I run this same rig with the older R-09.
For a loud show i have the Aerco set on +20db
and the R-09 set between 6-9 out of 30

70 out of 80 on the R-09HR doesn't seem right.

Some tapers have been reporting distortion problems recording
at 24/96 on bass heavy loud shows with the R-09HR with good levels.
Title: Re: Why did my recording fail ?
Post by: Datfly on October 10, 2008, 12:29:24 PM
I taped at 24 & 88

Looks like I need to do some test on a local band
where I can play around & do some testing.

Any other thoughts!

Datfly

I run this same rig with the older R-09.
For a loud show i have the Aerco set on +20db
and the R-09 set between 6-9 out of 30

70 out of 80 on the R-09HR doesn't seem right.

Some tapers have been reporting distortion problems recording
at 24/96 on bass heavy loud shows with the R-09HR with good levels.
Title: Re: Why did my recording fail ?
Post by: Dede2002 on October 10, 2008, 12:42:00 PM
IMO the safest thing to do is set your R-09HR at Unity gain: around 50.
Then use your preamp to achieve the desired levels.
Title: Re: Why did my recording fail ?
Post by: easy jim on October 10, 2008, 12:48:44 PM
IMO the safest thing to do is set your R-09HR at Unity gain: around 50.
Then use your preamp to achieve the desired levels.

QFT.

Also, are you 100% sure you were not accidentaly plugged into the mic input on the R-09HR instead of the line input?  Running a line level feed into the mic input would also cause that kind of brickwalling, though it wouldn't explain why you needed to increase the gain so much on the R-09HR to get a good level...
Title: Re: Why did my recording fail ?
Post by: nameloc01 on October 10, 2008, 01:01:10 PM
That would be due to god punishing you for taping Staind.
Title: Re: Why did my recording fail ?
Post by: Josephine on October 10, 2008, 01:06:40 PM
I think 70 is an awfully high setting for the R-09HR.
I would expect to use that type of setting at a softer acoustical gig.
Title: Re: Why did my recording fail ?
Post by: Dede2002 on October 10, 2008, 01:25:31 PM
IMO the safest thing to do is set your R-09HR at Unity gain: around 50.
Then use your preamp to achieve the desired levels.

QFT.

Also, are you 100% sure you were not accidentaly plugged into the mic input on the R-09HR instead of the line input?  Running a line level feed into the mic input would also cause that kind of brickwalling, though it wouldn't explain why you needed to increase the gain so much on the R-09HR to get a good level...

What I don't understand is why the levels were not showing the overload.
Title: Re: Why did my recording fail ?
Post by: Arni99 on October 10, 2008, 02:09:20 PM
Seems you overloaded your line-input stage with too much signal from the external preamp.
No matter how you set the leves on the recorder, it will clip anyway in this situation.

Title: Re: Why did my recording fail ?
Post by: Belexes on October 10, 2008, 02:59:56 PM
Seems you overloaded your line-input stage with too much signal from the external preamp.
No matter how you set the leves on the recorder, it will clip anyway in this situation.

I agree. Not sure on the Aerco, but my Church Audio pre has a spiffy led that goes red if I am overloading into the preamp.  If it goes red, I know to back off on the gain of the pre.
Title: Re: Why did my recording fail ?
Post by: Dede2002 on October 10, 2008, 03:07:27 PM
Seems you overloaded your line-input stage with too much signal from the external preamp.
No matter how you set the leves on the recorder, it will clip anyway in this situation.

I agree. Not sure on the Aerco, but my Church Audio pre has a spiffy led that goes red if I am overloading into the preamp.  If it goes red, I know to back off on the gain of the pre.

OK. If that was the problem, how come he had to set his input level at 70 to produce only
-12db to -6db rec level?
Title: Re: Why did my recording fail ?
Post by: datbrad on October 10, 2008, 04:00:52 PM
What I don't understand is why the levels were not showing the overload.

It sounds like you could be over driving the active electronics between the line input and the gain control, and because your levels stay in acceptable range, you are falsely led to think everything is just fine. Unfortunately, you only find out after you get home what happened. I don't understand how you would get this running gain so high on the recorder, meaning the gain from the pre was not too hot to handle. Seems weird, unless you were going mic in instead of line in, as someone else suggested.
Title: Re: Why did my recording fail ?
Post by: bluntforcetrauma on October 16, 2008, 11:27:22 AM
From my set ups I have the sonosax pre running shyof 20db and the edriol r-09 set at 7.  Yes only 7.  i used this setting for VAN halen, RUSH, etc.  usually around the 12th row floor.  if your setting your pre at 20db no way should the HR be that high.  AGain i am running the sonosax at 16db and the edirol at 7 and still i get close to clipping.
Title: Re: Why did my recording fail ?
Post by: boyacrobat on October 18, 2008, 02:03:37 AM


setting mic gain to low on ro9 will do nothing for your line in rec levels.
different inputs they are independant from one another.

to surf +20 a pro you must be.
you will become one

g

 
Title: Re: Why did my recording fail ?
Post by: Len Moskowitz (Core Sound) on October 25, 2008, 11:20:41 PM
Last night I tested my new set up. ...
According to my levels I was not peaking at all. ...
My problem was distortion. ...
Any bass at all is just simply distorted. ...
Ideas ? Sugestions ? Thoughts ?

You provide all the evidence necessary to point to mic pre-amp overload as the problem (popularly known as "brickwalling").  When the level controls in your recorder or pre-amp are physically after the gain stage, the gain stage can overload into distortion.  You can reduce it's already distorted output levels so that the meters show a reasonably low level.  They can fool you badly that way.

For 16-bit recording, the solution is to start with the lowest sensitivity switchable gain setting (Low instead of High) and low settings on the variable gain control, then slowly increase levels until you get close to clipping, and then back them off.

For 24-bit recording, you never have to get anywhere near clipping (0 dB) to record with a wide dynamic range -- after all you have more than 120 dB of range and most live concerts have less than 60 dB dynamic range -- so be very conservative.  You can always boost levels later (without adding any noise) in your computer.


Title: Re: Why did my recording fail ?
Post by: unclelouie on October 27, 2008, 04:55:41 PM
It sounds to me as though the mics can't handle the SPLs.  The "Any bass at all is just simply distorted..." comment makes me think this.

I had a similar issue when stealthing Frampton & Tull this summer.  I did a low sensitivity mod to my homebrew omnis and voila! problem solved.



 
Title: Re: Why did my recording fail ?
Post by: Len Moskowitz (Core Sound) on October 27, 2008, 04:58:31 PM
It sounds to me as though the mics can't handle the SPLs.  The "Any bass at all is just simply distorted..." comment makes me think this.

I had a similar issue when stealthing Frampton & Tull this summer.  I did a low sensitivity mod to my homebrew omnis and voila! problem solved.



Most of the energy at amplified concerts is in the bass -- that's why the problem first manifests there.

If you used an attenuator cable between the mics and the recorder's mic pre-amp input, you likely would have experienced the same relief in distortion.