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Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: jpschust on February 04, 2004, 03:40:48 PM

Title: Onboard A/D Comparisons?
Post by: jpschust on February 04, 2004, 03:40:48 PM
Has anyone done an onboard A/D comparison of the basic gear we often use?  Here are my thoughts as to what should be compared (all at line level)

D7
D8
D100
M1
DAP1
D10
VxPocket
JB3

all at 16/44.1  I'd be interested to hear the results
Title: Re:Onboard A/D Comparisons?
Post by: dmonterisi on February 04, 2004, 03:59:56 PM
i think you just proposed that someone else do an 8 deck source comp and that you'd be interested in hearing the results!  excellent delegation skills! :P
Title: Re:Onboard A/D Comparisons?
Post by: marc0789 on February 04, 2004, 04:05:34 PM
if someone sends me everything but an hhb and m1, I'll do it. But the decks are my administrative fee.  ;D

Seriously, I've been most impressed by the m1 a/d stage, more than the da-p1 and maybe even the hhb. Smooth, grainless, just very nice.
Title: Re:Onboard A/D Comparisons?
Post by: scb on February 04, 2004, 04:06:18 PM
well the d100 and m1 are the same, so it's down to 7 :)
Title: Re:Onboard A/D Comparisons?
Post by: jpschust on February 04, 2004, 04:12:29 PM
well heres the issue- they all need to go line in from the same source- meaning that the D/A from the original source needs to be the same (i suggest using a cd player or something of that nature).  id do it myself but i just dont have access to all those decks.
Title: Re:Onboard A/D Comparisons?
Post by: nic on February 04, 2004, 04:28:41 PM
the M1's ad stage is fine if you keep the levels relatively low(peaking about -6 or so, not higher). if you run hot levels you will notice in a wave editor that the levels on the bottom side of the waveform are somewhat "tabeled" for lack of a better word, not as dynamic looking as the levels on the topside
Title: Re:Onboard A/D Comparisons?
Post by: Brian Skalinder on February 04, 2004, 04:32:56 PM
Heh, at the moment I have a D7, D8, D100, and JB3 - over halfway there!  Ideally, I'd wanna do it in the field, not at home in front of the home stereo or straight from a playback device (CD, etc.).  I could probably run Mics > V3 analog outs > splitters up the wazoo > 4 recording devices.  Dunno if I can find time to swing this, but I may try to give it a go.  No promises, though...
Title: Re:Onboard A/D Comparisons?
Post by: Tim on February 04, 2004, 04:36:16 PM
the M1's ad stage is fine if you keep the levels relatively low(peaking about -6 or so, not higher). if you run hot levels you will notice in a wave editor that the levels on the bottom side of the waveform are somewhat "tabeled" for lack of a better word, not as dynamic looking as the levels on the topside

if this is true then I'd say the m1's adc is pretty worthless... when recording in 16bit you're going to need hotter levels than that or you're losing out on quality.
Title: Re:Onboard A/D Comparisons?
Post by: chase on February 04, 2004, 04:37:26 PM
luvean, sounds like it could be a DC offset problem if it looks as though entire wave pattern should be shifted downward.
Title: Re:Onboard A/D Comparisons?
Post by: nic on February 04, 2004, 04:43:15 PM
the M1's ad stage is fine if you keep the levels relatively low(peaking about -6 or so, not higher). if you run hot levels you will notice in a wave editor that the levels on the bottom side of the waveform are somewhat "tabeled" for lack of a better word, not as dynamic looking as the levels on the topside

if this is true then I'd say the m1's adc is pretty worthless... when recording in 16bit you're going to need hotter levels than that or you're losing out on quality.

true, I've noticed over the past few months since I havent had a "portable" pre/adc.
as long as I kept the levels peaking between 12-6 the resulting waveform seemed fine, but just a bit on the quiet side. however, I would then just apply a 6db or so gain to the waveform and it was fine.
I'm sure there are some who would say that this is not restoring any fidelity lost in the original recording, but since I dont have a high-end playback system I cant hear any added background noise, if any...have played back such a edited recording in the studio and we couldnt hear any added noise...ymmv
Title: Re:Onboard A/D Comparisons?
Post by: nic on February 04, 2004, 04:44:31 PM
luvean, sounds like it could be a DC offset problem if it looks as though entire wave pattern should be shifted downward.

if so then the DC offset is coming from the DAT and not the transfer card, but then why would it only appear with HOT levels?
Title: Re:Onboard A/D Comparisons?
Post by: jpschust on February 04, 2004, 04:48:48 PM
Heh, at the moment I have a D7, D8, D100, and JB3 - over halfway there!  Ideally, I'd wanna do it in the field, not at home in front of the home stereo or straight from a playback device (CD, etc.).  I could probably run Mics > V3 analog outs > splitters up the wazoo > 4 recording devices.  Dunno if I can find time to swing this, but I may try to give it a go.  No promises, though...

why not just do it the purest way possible- run analog out of your cd player and just keep running the same track through each of them.  no need for splitters or any other pain in the ass stuff.
Title: Re:Onboard A/D Comparisons?
Post by: dmonterisi on February 04, 2004, 04:55:10 PM
because you're trying to test the a/d's performance in a field environment.  cd's are, generally speaking, much more compressed and doctored.  in a concert recording environment, the wider dynamic range could pose different issues for a a>d than recording from a cd.  
Title: Re:Onboard A/D Comparisons?
Post by: jpschust on February 04, 2004, 05:01:33 PM
alright fair enough.  the issue is getting the same quality of source through every single A/D in the same exact setting.  even with the compression and range of a CD, it would be better to be testing just basic tones.  if ya wanna be really pure about it also test white and pink noise
Title: Re:Onboard A/D Comparisons?
Post by: dmonterisi on February 04, 2004, 05:04:19 PM
you're absolutely right, but if you're gonna do this test, might as well do it right. :P  i don't particularly see the value in it at all in this late stage of the dat game, but that's just me.
Title: Re:Onboard A/D Comparisons?
Post by: jpschust on February 04, 2004, 05:19:08 PM
damon, i think that while we are at the late stage of the DAT game i think we are going to see DAT's in the field for quite a while to come.  At least until the HD recorders come way down in price, around the 500 dollar or below mark.
Title: Re:Onboard A/D Comparisons?
Post by: rustoleum on February 04, 2004, 05:21:35 PM
What about taking the line out of a 24 bit playback device playing a live show recorded at 24 bit?   Obviously a good DA convertor would be ideal, but even the headphone out of a computer would cut it.  That should give you more than enough dynamic range (certainly more than both a comerical CD and a live DAT)  to get an idea of what each A/D would sound like in a live setting.  

Whatever the case,  I agree that it may not be worth the trouble, but I think this solution gives a nice controlled situation that would exercise the deck the way we would in the field.

Rusty
Title: Re:Onboard A/D Comparisons?
Post by: marc0789 on February 04, 2004, 05:31:00 PM
done a handful of stealth shows running >mp2>m1 and always been impressed, generally run the mp2 about 1/3 to 1/2 and the m1 maybe at 5-6, nice smooth sound.
Title: Re:Onboard A/D Comparisons?
Post by: super-phat-al on February 04, 2004, 06:49:45 PM
i can tell you i can't stand the ADC on the d8.  To me i lost of sound in that stage when i was runng C1000s>Mixpad>d8.  
Title: Re:Onboard A/D Comparisons?
Post by: jpschust on February 04, 2004, 08:10:09 PM
ok all these descriptions are all good and well, and i could probably use verbage to describe all of them, but it doesnt equal having a sampler download to compare it all to.  a set of 1-2 minute flac files where pink noise and other colored noise is generated would be more helpful in  the long run
Title: Re:Onboard A/D Comparisons?
Post by: Tim on February 04, 2004, 08:14:25 PM
let us know when you finish!
Title: Re:Onboard A/D Comparisons?
Post by: jpschust on February 04, 2004, 08:17:17 PM
if i can borrow the gear from people id be happy to do the tests, problem is i just dont own all the gear to do it.
Title: Re:Onboard A/D Comparisons?
Post by: scb on February 04, 2004, 09:02:57 PM
>>because you're trying to test the a/d's performance in a field environment.  cd's are, generally speaking, much more compressed and doctored.  in a concert recording environment, the wider dynamic range could pose different issues for a a>d than recording from a cd. <<

so use a live cd :)
Title: Re:Onboard A/D Comparisons?
Post by: sickrick43 on February 05, 2004, 12:08:16 AM

Take the D10 (Pro) out of the loop.  Unless it's been line-mod'd, it's running @ +4 line levels anyway.  The mike pre on it's pretty quiet, and the a/d is OK.  There's always room for improvement with an input mod.

For it's vintage, out of the box, it's the cadillac (and for the most part, there hasn't been a portable pro dat that's really come close).

My $.02

Rick
Title: Re:Onboard A/D Comparisons?
Post by: jpschust on February 05, 2004, 12:09:24 AM
i want everything stock.  no mods whatsoever.
Title: Re:Onboard A/D Comparisons?
Post by: Sean Gallemore on February 05, 2004, 02:18:40 AM
done a handful of stealth shows running >mp2>m1 and always been impressed, generally run the mp2 about 1/3 to 1/2 and the m1 maybe at 5-6, nice smooth sound.

I'm running the same and am always amazed with the sound, i run mp-2 at 9'oclock and the m1 from 5-7.  I run hot, too.  It just sounds better with the increased dynamics, plus I can't "hear" any tabling, but maybe that's just my shitty system.
Title: Re:Onboard A/D Comparisons?
Post by: zhianosatch on February 05, 2004, 03:07:59 AM
>>because you're trying to test the a/d's performance in a field environment.  cd's are, generally speaking, much more compressed and doctored.  in a concert recording environment, the wider dynamic range could pose different issues for a a>d than recording from a cd. <<

so use a live cd :)

such crazy ideas, scott. ;)
Title: Re:Onboard A/D Comparisons?
Post by: Sean Gallemore on February 05, 2004, 03:18:16 AM
>>because you're trying to test the a/d's performance in a field environment.  cd's are, generally speaking, much more compressed and doctored.  in a concert recording environment, the wider dynamic range could pose different issues for a a>d than recording from a cd. <<

so use a live cd :)

such crazy ideas, scott. ;)
 but there's no w00k factor, takes all the fun out of it
Title: Re:Onboard A/D Comparisons?
Post by: Mic D on February 05, 2004, 10:49:38 AM
the M1's ad stage is fine if you keep the levels relatively low(peaking about -6 or so, not higher).

 :sick: