Become a Site Supporter and Never see Ads again!

Author Topic: Linking two V3's question  (Read 3642 times)

0 Members and 1 Guest are viewing this topic.

Offline OFOTD

  • Amorican
  • Trade Count: (7)
  • Needs to get out more...
  • *****
  • Posts: 6310
Linking two V3's question
« on: October 30, 2007, 01:25:45 PM »
So gumbino and I are going to try to attempt a new V3 a/d comp.    Here's how I see it going down.

Mics  >  V3  >  recorder
             |
             | (analog out)
             |   
            V3  >  recorder

We'll be running analog out of the the first V3 into the XLR inputs of the second V3.  Of the second V3 all we're planning on using is the a/d section.  The pres of only the first V3 will be used.

Anyone hooked up two V3's like this before?  Any thoughts?  Things to beware of?

 

Offline TNJazz

  • Ninja
  • Trade Count: (44)
  • Needs to get out more...
  • *****
  • Posts: 5537
  • Gender: Male
  • "Those who know, know."
    • NINJA DYNAMITE
Re: Linking two V3's question
« Reply #1 on: October 30, 2007, 01:41:36 PM »
Why?  I guess I don't get what you're trying to compare.
Check out my band!  --> http://www.ninjadynamite.com

Offline Tim

  • Trade Count: (1)
  • Needs to get out more...
  • *****
  • Posts: 32925
  • Gender: Male
Re: Linking two V3's question
« Reply #2 on: October 30, 2007, 01:44:52 PM »
Why?  I guess I don't get what you're trying to compare.
I’ve had a few weird experiences and a few close brushes with total weirdness of one sort or another, but nothing that’s really freaked me out or made me feel too awful about it. - Jerry Garcia

Offline eric.B

  • to the side qualified
  • Trade Count: (0)
  • Needs to get out more...
  • *****
  • Posts: 2801
Re: Linking two V3's question
« Reply #3 on: October 30, 2007, 01:59:21 PM »
Why?  I guess I don't get what you're trying to compare.

ISO: Neumann AK20 x1
Mics: AKG 480/ck62/ck63  * Neumann KM100 x2/ak40 x3
Pres: Oade ACM Lunatec V3 * Oade m248
Cables: HiHo Silver Interconnects and XLR's
Recorders: Oade Warm Mod R4 Pro / D8 / D10Pro II

Im guessing the v3 listed above and a stock one......................
We have a system that increasingly taxes work and subsidizes nonwork.  ~Milton Friedman

Offline OFOTD

  • Amorican
  • Trade Count: (7)
  • Needs to get out more...
  • *****
  • Posts: 6310
Re: Linking two V3's question
« Reply #4 on: October 30, 2007, 02:11:40 PM »
Yes we are doing a comp of the A/D sections of the stock V3 and the ACM V3.

We'll be running a pair of 4023's into a stock V3.  We'll then run the analog outs of the stock V3 into the analog inputs of the ACM V3.   So we'll just be using the pre on the stock V3.

I thought about the built-in attenuators in the V3 but are they necessary since i'll be feeding it an analog signal from the stock V3?


Offline Tim

  • Trade Count: (1)
  • Needs to get out more...
  • *****
  • Posts: 32925
  • Gender: Male
Re: Linking two V3's question
« Reply #5 on: October 30, 2007, 02:14:14 PM »
Ahhh, sorry I totally missed that.

good luck. their doesn't seem to be much out there on the ACM V3, what little their is seems positive though
I’ve had a few weird experiences and a few close brushes with total weirdness of one sort or another, but nothing that’s really freaked me out or made me feel too awful about it. - Jerry Garcia

Offline Brian Skalinder

  • Complaint Dept.
  • Trade Count: (28)
  • Needs to get out more...
  • *****
  • Posts: 18886
  • Gender: Male
Re: Linking two V3's question
« Reply #6 on: October 30, 2007, 02:32:38 PM »
I think You're going to need to attenuate the signal before the 2nd V3, but I'm drawing a blank on the V3's input specs right now.  I'd skip the attenuation bit and use a transformer isolated XLR splitter, instead:

                  /--- V31 (w/ phantom) > recorder
Mics >  splitter > 
                  \--- V32 (w/o phantom) > recorder


In either case, you'll have challenges matching levels precisely, so might as well remove the unnecessary gain structure / attenuation (gain > attenuation > gain) from the equation.
Milab VM-44 Links > Fostex FR-2LE or
Naiant IPA (tinybox format) >
Roland R-05

Offline OFOTD

  • Amorican
  • Trade Count: (7)
  • Needs to get out more...
  • *****
  • Posts: 6310
Re: Linking two V3's question
« Reply #7 on: October 30, 2007, 02:35:09 PM »
I think You're going to need to attenuate the signal before the 2nd V3, but I'm drawing a blank on the V3's input specs right now.  I'd skip the attenuation bit and use a transformer isolated XLR splitter, instead:

                  /--- V31 (w/ phantom) > recorder
Mics >  splitter > 
                  \--- V32 (w/o phantom) > recorder


In either case, you'll have challenges matching levels precisely, so might as well remove the unnecessary gain structure / attenuation (gain > attenuation > gain) from the equation.

I should have just come to you first Brian.  :)   +T

Then that begs the question does anyone have a transformer isolated XLR splitter I can borrow this weekend?


Offline Brian Skalinder

  • Complaint Dept.
  • Trade Count: (28)
  • Needs to get out more...
  • *****
  • Posts: 18886
  • Gender: Male
Re: Linking two V3's question
« Reply #8 on: October 30, 2007, 03:22:41 PM »
Then that begs the question does anyone have a transformer isolated XLR splitter I can borrow this weekend?

I've always used XLR splitter cables, not isolated.  They work fine, but are not ideal.  Keep meaning to pick up a proper splitter box, but haven't gotten around to it.  If you can't find a loaner, Guitar Center has a transformer isolated splitter box for $35/ea.  So...options:

  • loaner TI splitter box (good luck!)
  • pick up two of the Guitar Center boxes (and return them the next day?)  :P
  • pick up plain old cable splitters
  • I can send you my cable splitters (though after shipping both ways, the new ones probably aren't hugely more expensive)
Milab VM-44 Links > Fostex FR-2LE or
Naiant IPA (tinybox format) >
Roland R-05

Offline it-goes-to-eleven

  • Trade Count: (58)
  • Needs to get out more...
  • *****
  • Posts: 6703
Re: Linking two V3's question
« Reply #9 on: October 30, 2007, 03:35:02 PM »
Gonna go out on a limb and suggest that any $35 splitter box is going to have really mediocre transformers... but it'd be great if that wasn't the case.

Since you are using the same pre-amp in both cases, I would be less worried about using a passive splitter than if you were running two different pre-amps (this assumes the oade v3 mod is just on the a/d section, as has been suggested).

New product - Get your NEUMANN active mounting bars
Active microphone mounting bars for Schoeps and AKG, and Naiant AKG, ready to ship

Offline JasonSobel

  • Trade Count: (8)
  • Needs to get out more...
  • *****
  • Posts: 3329
  • Gender: Male
    • My show list
Re: Linking two V3's question
« Reply #10 on: October 30, 2007, 03:36:03 PM »
here's a couple of thoughts...

Brian's comments are spot on.  There is no way to NOT run the signal through the pre-amp of the V3 and only use the A/D (i.e. if you went V3 > analog > ACM V3, even if you use the internal attenuators and got the levels right, you'd still be passing the signal through the second V3's pre-amp).

That said, it seems like the best way is as Brian described, using some sort of splitter.  As far as level matching between the two units, other threads have described the ACM V3 as being more sensitive, i.e. a lower input level results in 0dBfs relative to a stock V3.  Based on that, you should get everything set up before hand, and then set the gain on the two V3's to be identical.  for example, 20dB and all the trim knobs at 0dB.  Then take both recorded files to a computer, and look at the overall level.  Whatever the difference in levels between the two files is equal to the difference in sensitivity between the units.  Now you know the difference between them, so you can adjust accordingly in the field, i.e. if you find a 10dB difference in those recordings, at the show, you can adjust the stock V3 exactly 10dB higher.  with this method, you should be able to get the final levels very close, and thus have a better comparison...

Offline Brian Skalinder

  • Complaint Dept.
  • Trade Count: (28)
  • Needs to get out more...
  • *****
  • Posts: 18886
  • Gender: Male
Re: Linking two V3's question
« Reply #11 on: October 30, 2007, 03:52:28 PM »
Gonna go out on a limb and suggest that any $35 splitter box is going to have really mediocre transformers... but it'd be great if that wasn't the case.

Ahhh...good point.   :-\

Any handy TSer want to contribute some time building a quality transformer isolated splitter box (2 > 4) we can pass around as necessary?  I'll chip in some cash for parts and such.
Milab VM-44 Links > Fostex FR-2LE or
Naiant IPA (tinybox format) >
Roland R-05

Offline TNJazz

  • Ninja
  • Trade Count: (44)
  • Needs to get out more...
  • *****
  • Posts: 5537
  • Gender: Male
  • "Those who know, know."
    • NINJA DYNAMITE
Re: Linking two V3's question
« Reply #12 on: October 30, 2007, 04:33:20 PM »
Why does it need to be transformer isolated?  That WILL change the sonic characteristics of the signal passing through it.

I think for a test like this you truly want a parallel passive split - you just want to be careful about applying phantom from only one side...

The only way it would be equal would be to have a 3 way split with both the isolated sides running to the preamps, but then you'd still need a third device to supply the phantom power.
Check out my band!  --> http://www.ninjadynamite.com

Offline baustin

  • Trade Count: (4)
  • Needs to get out more...
  • *****
  • Posts: 2781
  • Gender: Male
Re: Linking two V3's question
« Reply #13 on: October 31, 2007, 11:50:39 AM »
I've never done this, but I was always under the assumption that you could run phantom power on both units. I have absolutely nothing to base this on, I just thought this was what I've read. I feel like Marc Nutter posted some stuff about this a long while back while testing different pre-amps.

I could've sworn he ran mics->standard xlr splitter->2 preamps both with phantom power.

Obviously I'm not gonna try this with the u89i's first, but I have considered doing it.

Offline it-goes-to-eleven

  • Trade Count: (58)
  • Needs to get out more...
  • *****
  • Posts: 6703
Re: Linking two V3's question
« Reply #14 on: October 31, 2007, 12:00:06 PM »
I'm not sure about the single vs. dual phantom source.

I've done splitter comps with both pre-amps sending phantom.  One time I had problems with distorted bass and I was pretty sure that I forgot to enable phantom on one of the pre-amps. So my tendency is to enable both phantom sources.

I kinda wonder if the single-phantom case suffers from additional load due to the second pre?

New product - Get your NEUMANN active mounting bars
Active microphone mounting bars for Schoeps and AKG, and Naiant AKG, ready to ship

 

RSS | Mobile
Page created in 0.136 seconds with 56 queries.
© 2002-2020 Taperssection.com
Powered by SMF