Where did this clipping come from? at DVinfo.net

Tom Morrow · May 9th, 2012, 11:55 AM

I was borrowing a Tascam DR100 recorder, and decided to test it out side by side with my Tascam DR-05 recorder that I normally use. Strangely I got some audible clipping in the DR100 recording but not the DR-05 recording, even though neither went above about -3db. I can't figure out what caused it, curious if others have ideas. The original recording files are attached.

The clipping happens at about :50 into the dr100 recording (about :52 into the dr-05 recording) when the actor says "Si por regado" (pardon the english-speaking actors butchering the spanish... this is a dream sequence :-)

The recordings were done with a Sanken cs-3e boom mic, fed into a SD Mixpre, which fed the DR-05 though tape output (consumer line level), and fed the DR100 through the line level XLR outputs. The DR100 recording ended up a little bit hotter (even though I turned the level down to zero, the SD has nice and hot outputs), but not hot enough to go into recorder clipping, unless I'm missing something.

I checked now and the switches on the DR100 were: Mic gain: M, Auto/Limiter: Off, 48V: off, Speaker: off. Front panel input switch set to XLR. Record settings menu: Wav 48k/24bit/2G. Pre-rec: off, delay: off.

The only thing I can think of is that there is some defect in the SD mixpre line level outputs that doesn't effect the tape outs. I do normally use the tape outs instead of XLR line outs. But that seems very unlikely to be the cause... any ideas?

Tom Morrow · May 9th, 2012, 12:28 PM

Sorry, the upload of the files failed since they are too big, and I don't have time to trim right now so I will post trimmed versions probably this evening.

Ty Ford · May 9th, 2012, 12:39 PM

were the 100 inputs set to mic or line?

Ty Ford

Rick Reineke · May 9th, 2012, 12:54 PM

Same question as Ty: "were the 100 inputs set to mic or line?"
Mic level probably, if Tom was using a 1st gen. DR-100, the XLRs were not mic/line switchable..
The DR-100 has a separate 1/8" line in (unbalanced -10dB) I think the DR-100mkII is like the DR40, with a mic/line switch.

Tom Morrow · May 9th, 2012, 03:28 PM

Aha... I think you guys have nailed it.

I was misusing the XLR mic inputs by feeding them a line signal. That would explain why I had to turn the level dial down to 0 and still got a slightly hot signal. In theory this should not be a problem, but I suspect the analog circuitry in the DR100 overloaded at some stage before it got to the ADC.

Next time I suppose I'd use an XLR->TR plug with some pads to get the levels matched if I had to use the DR100 with the Mixpre, but it'd be better just to go with the dr100mk2 version which supports line in.

Lesson learned: if a gain dial is either all the way up or all the way down, something needs to be fixed.

Ty Ford · May 9th, 2012, 04:09 PM

I almost did it to myself today at a new client's. I was feeding little hard drive video decks. I didn't even know they had a headphone out until we were rolling. I had sent tone everything looked ok. I was sending line level from my mixer.

I was suddenly gripped by the thought that I had never confirmed mic or line level on the deck.

I found a headphone jacks and breathed a sigh of relief as I heard audio that was not distorted.

The take away message is: ALWAYS LISTEN!

Regards,

Ty Ford

Tom Morrow · May 9th, 2012, 10:29 PM

Just for completeness, here are the two recordings, shortened down so you just hear the clipped part.

I've tried a lot of recorders, but still haven't found a bag-friendly, reasonably priced recorder that I like. The DR100 does have a nice wired remote with recording LED that makes it more bag-friendly, but you still can't see the display with file number (or meter) in a bag.

May 9th, 2012, 11:55 AM	#1
Tom Morrow Major Player Join Date: Feb 2011 Location: San Francisco, CA Posts: 416	Where did this clipping come from? I was borrowing a Tascam DR100 recorder, and decided to test it out side by side with my Tascam DR-05 recorder that I normally use. Strangely I got some audible clipping in the DR100 recording but not the DR-05 recording, even though neither went above about -3db. I can't figure out what caused it, curious if others have ideas. The original recording files are attached. The clipping happens at about :50 into the dr100 recording (about :52 into the dr-05 recording) when the actor says "Si por regado" (pardon the english-speaking actors butchering the spanish... this is a dream sequence :-) The recordings were done with a Sanken cs-3e boom mic, fed into a SD Mixpre, which fed the DR-05 though tape output (consumer line level), and fed the DR100 through the line level XLR outputs. The DR100 recording ended up a little bit hotter (even though I turned the level down to zero, the SD has nice and hot outputs), but not hot enough to go into recorder clipping, unless I'm missing something. I checked now and the switches on the DR100 were: Mic gain: M, Auto/Limiter: Off, 48V: off, Speaker: off. Front panel input switch set to XLR. Record settings menu: Wav 48k/24bit/2G. Pre-rec: off, delay: off. The only thing I can think of is that there is some defect in the SD mixpre line level outputs that doesn't effect the tape outs. I do normally use the tape outs instead of XLR line outs. But that seems very unlikely to be the cause... any ideas?

May 9th, 2012, 12:28 PM	#2
Tom Morrow Major Player Join Date: Feb 2011 Location: San Francisco, CA Posts: 416	Re: Where did this clipping come from? Sorry, the upload of the files failed since they are too big, and I don't have time to trim right now so I will post trimmed versions probably this evening.

May 9th, 2012, 12:39 PM	#3
Ty Ford Inner Circle Join Date: Nov 2004 Location: Baltimore, MD USA Posts: 2,337	Re: Where did this clipping come from? were the 100 inputs set to mic or line? Ty Ford __________________ Ty Ford's Audio Bootcamp Field Guide Ty Ford's Audio Video Blog

May 9th, 2012, 12:54 PM	#4
Rick Reineke Inner Circle Join Date: Aug 2008 Location: New York Posts: 2,039	Re: Where did this clipping come from? Same question as Ty: "were the 100 inputs set to mic or line?" Mic level probably, if Tom was using a 1st gen. DR-100, the XLRs were not mic/line switchable.. The DR-100 has a separate 1/8" line in (unbalanced -10dB) I think the DR-100mkII is like the DR40, with a mic/line switch.

May 9th, 2012, 03:28 PM	#5
Tom Morrow Major Player Join Date: Feb 2011 Location: San Francisco, CA Posts: 416	Re: Where did this clipping come from? Aha... I think you guys have nailed it. I was misusing the XLR mic inputs by feeding them a line signal. That would explain why I had to turn the level dial down to 0 and still got a slightly hot signal. In theory this should not be a problem, but I suspect the analog circuitry in the DR100 overloaded at some stage before it got to the ADC. Next time I suppose I'd use an XLR->TR plug with some pads to get the levels matched if I had to use the DR100 with the Mixpre, but it'd be better just to go with the dr100mk2 version which supports line in. Lesson learned: if a gain dial is either all the way up or all the way down, something needs to be fixed.

May 9th, 2012, 04:09 PM	#6
Ty Ford Inner Circle Join Date: Nov 2004 Location: Baltimore, MD USA Posts: 2,337	Re: Where did this clipping come from? I almost did it to myself today at a new client's. I was feeding little hard drive video decks. I didn't even know they had a headphone out until we were rolling. I had sent tone everything looked ok. I was sending line level from my mixer. I was suddenly gripped by the thought that I had never confirmed mic or line level on the deck. I found a headphone jacks and breathed a sigh of relief as I heard audio that was not distorted. The take away message is: ALWAYS LISTEN! Regards, Ty Ford __________________ Ty Ford's Audio Bootcamp Field Guide Ty Ford's Audio Video Blog