Mic Input gain vs ouput vs mic input on digi 003 factory

Mr. ROUSH

Mr. ROUSH

Active member
Ok.. something I have struggled with repeatedly is understanding gain staging.. specifically my trouble is that I don't think I truly grasp the application.

My setup is a u87 through the isa220 into the digi 003 factory

the isa provides 0-60db gain at the input stage and then the digi 003 input stage provides 15 to 60db.. So.. I don't understand truly where these should be in relation to each other.. I realize that metering is the most important concept when considering these settings.. but I just don't grasp it..

there are any different number of ways I can end up between -6 to -12 on the board, but what is right and what is wrong.. I know there is no exact right answer to this.. but can someone help me to better understand some general rules of thumb? Some kind of middle ground to keep me at acceptable levels without missing out on the sonic qualities of the preamp etc.. ?

For example through my own trial and error.. I have my input gain set around 30 - 35 db for most.. when I need a bit more for softer singers I'll use the trim on the isa to kick it up towards 40db.. I have the input on the board nealry at it's lowest setting, probably around 19 - 20 db.. the lowest being 15db. So.. judging from that.. am I totally off the mark here?

Any help or advice would be so greatly appreciated.. I've racked my brain trying to make sure I undestand this and as soon as I think I've got it figured out.. I don't.. the info on the net is so convaluted to me.. and maybe I'm missing something.. but I have yet to find a laymen's explination at this site or anywhere that isn't spanish to me.. Thanks in advance for any advice you can give!!
 
I may be confused, Mr. Roush, so help me out here. I use a Digi002, and the configuration is similar, according to the specs. The 002 and 003 both have 8 analog inputs, in addition to digital inputs. The isa220 uses analog output, by XLR, or can use an optional digital card which outputs by S/PDIF, AES/EBU, or Toslink (optical). Assuming the Focusrite doesn't have the digital card installed, you would send your line out by XLR , to the TRS 1/4" input on any of channels 5-8, *not* channels 1-4. Channels 1-4 on the 003 have there own preamps. Channels 5-8 have no preamps, they are just line ins. The gain staging is simple, because there is no reason to plug a superior preamp into an inferior preamp. That is assuming that you think the isa220 is a better pre than the ones in the 003. I've never used either one, so I can't comment on that. Obviously, if you thought the 003's pres were better than the Focusrite, you'd just plug the U87 into the 003.

If you do have the digital card installed in the Focusrite, you have to decide which unit has better A-D conversion. If you think the Focusrite's A-D conversion is better, you would send the digital signal to the 003 via S/PDIF, and probably slave the Focusrite to the 003.

The main point is- there is no blessed reason to plug one preamp into another preamp, so you get the noise floor of both units. Am I missing something here?-Richie
 
yeah, I really don't know much about yer gear but I'd see if there was a bypass on the onboard pres when you're using the outboard
or not use the outboard pre.
Runnin a pre into a pre is just gonna give ya more noise.
 
Richard Monroe said:
I may be confused, Mr. Roush, so help me out here. I use a Digi002, and the configuration is similar, according to the specs. The 002 and 003 both have 8 analog inputs, in addition to digital inputs. The isa220 uses analog output, by XLR, or can use an optional digital card which outputs by S/PDIF, AES/EBU, or Toslink (optical). Assuming the Focusrite doesn't have the digital card installed, you would send your line out by XLR , to the TRS 1/4" input on any of channels 5-8, *not* channels 1-4. Channels 1-4 on the 003 have there own preamps. Channels 5-8 have no preamps, they are just line ins. The gain staging is simple, because there is no reason to plug a superior preamp into an inferior preamp. That is assuming that you think the isa220 is a better pre than the ones in the 003. I've never used either one, so I can't comment on that. Obviously, if you thought the 003's pres were better than the Focusrite, you'd just plug the U87 into the 003.

If you do have the digital card installed in the Focusrite, you have to decide which unit has better A-D conversion. If you think the Focusrite's A-D conversion is better, you would send the digital signal to the 003 via S/PDIF, and probably slave the Focusrite to the 003.

The main point is- there is no blessed reason to plug one preamp into another preamp, so you get the noise floor of both units. Am I missing something here?-Richie
Click to expand...

I'm quite certain that you have likely solved my problem %100, but let me make sure I understand.. So I was under the impression going xlr to 1/4" trs to input 1 was no different then 5-8.. I thought only the xlr input went through the pre on inputs 1-4? So then truth is that the 1/4" in's 1-4 go through the pre's?

You know.. the more I think about it.. wow.. this has been obvious right in my face the whole time.. explains why only 1-4 have gain adjustments and are switchable between the Mic/DI..

Yeah, I'm fairly certain this has been my missing link..

With gratitude my friend.. thanks whole heartedly.. You have no idea the turmoil this has caused in my head.. I can't believe I didn't pick up on that, or even just randomly try other inputs for comparison..

Thanks a million!
 
What an unbelievable diference!!! As absurd as my problem was.. stacking the pre's like that.. you have no idea how much trouble it caused a crossed the whole spectrum of recording for me.. the instruments as well since I was mixing them to horrible vocals.. nothing for the instruments to do but sound horrible with them..

This small easily identifiable problem has caused me to question everything I've ever learned.. made me question why I wasn't getting desired results from top shelf gear using common, known teqniques.. this little problem has hindered me since... get this.. April of 2008 since I got the 003.. for that long I've been recording absolute garbage!!

All the while I knew, as does hopefully everyone.. you shouldn't stack pre's.. and just didn't realize that I was doing that.. Talk about a "doh!" moment!

I can't thank you enough! I feel like I can FINALLY get back to actually making records!

As stupid as that was.. I have to say.. it forced me to learn just about everything else in the process.. guess it's all for a reason...

So anyway, long story short.. I owe you one Mr. Monroe!!! Big Time!!!
 
Glad to be of assistance! I'm another guy who is sometimes mystified by my own gear. I'll tell you what- just send me that U87 and we'll call it even (LOL). Better yet- Buy my album. It rocks.-Richie
 
Richard Monroe said:
Glad to be of assistance! I'm another guy who is sometimes mystified by my own gear. I'll tell you what- just send me that U87 and we'll call it even (LOL). Better yet- Buy my album. It rocks.-Richie
Click to expand...


LOL.. well I'm afraid I've become a bit too attached to the german to let it go, especially now, and all thanks to you..

that being said, I most certainly will buy your album.. I would be glad to.. and I'll let other people hear it who will be likely to buy it.. shoot me the link and I'm sold.. least I can do.
 
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