Topic: V3>R4 Analog question

[Weirdness]

OK, I rent an R4 for a local Jazzfest that happens every year and do an onstage/SBD matrix.  The R4 will not do digital and analog at the same time so I run the digi out of the V3 to another deck and I run XLR out from the V3 to the R4.  Last year when I tried everything out, the signal from the V3 to the R4 was running way too hot and I ended up running attenuators to back it off a bit.  I had a brief conversation with the guy at the rental place and he suggested that switching the 2 channels from Line to Mic in would solve that issue.  Would this work OK?  The V3's XLR outs are line level as far as I know but I think that the issue has to do with pro/consumer levels. 

Anyways, if anyone can tell me if switching the deck to mic in is an acceptable way of doing things I would appreciate it. 

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OK, I rent an R4 for a local Jazzfest that happens every year and do an onstage/SBD matrix.  The R4 will not do digital and analog at the same time so I run the digi out of the V3 to another deck and I run XLR out from the V3 to the R4.  Last year when I tried everything out, the signal from the V3 to the R4 was running way too hot and I ended up running attenuators to back it off a bit.  I had a brief conversation with the guy at the rental place and he suggested that switching the 2 channels from Line to Mic in would solve that issue.  Would this work OK?  The V3's XLR outs are line level as far as I know but I think that the issue has to do with pro/consumer levels. 

Anyways, if anyone can tell me if switching the deck to mic in is an acceptable way of doing things I would appreciate it. 

Stay on line in with the R4, and consider using -20db inline pads on the way into the R4. The problem arrises in how the levels on the V3 are represented visually and what it's pumping out are not the same.

Read here for more info and a handy graph (seriously, I should bookmark this, I've had to reference it at least twice in the last 2 months). You'll need to look up what the max signal is on the R4, but I bet it's around +4db.

[JasonSobel]

Stay on line in with the R4, and consider using -20db inline pads on the way into the R4. The problem arrises in how the levels on the V3 are represented visually and what it's pumping out are not the same.

Read here for more info and a handy graph (seriously, I should bookmark this, I've had to reference it at least twice in the last 2 months). You'll need to look up what the max signal is on the R4, but I bet it's around +4db.

the part of your quote that I bolded isn't quite true.  The meter on the V3 is a very accurate representation of the digital levels after the signal goes through the V3's A/D.  The problem is that each A/D converter has a different sensitivity (i.e. different analog levels are required to get to the same max digital level, 0dBfs).  So when you send an analog signal out of the V3, you can't solely rely on the V3's level meter, because the digital levels you get will largely depend on whatever A/D you are using (in your case, the internal A/D on the R4).  The table in the link above is a good reference (and straight from the V3's manual).  However, it is also not fair to say that in all instances, the V3 has to be run much lower than normal.  in this thread, for example:
http://taperssection.com/index.php/topic,80074.msg1066556.html#msg1066556
you can see that running analog out of the V3 into a 722, the levels can be calibrated such that the digital levels from the V3 match exactly the digital levels on a 722 when running analog out of a V3.

All that said, what you need to know is what the max analog level is on the R4, when running line-in.  The specs in the R4 manual say this:
Line Level: -33– +4 dBu

based on those specs, and the table from the V3, the V3 will output a +4dBu signal when the second green LED comes on.  This is the LED that corresponds to -21dBfs for the V3's own digital levels, which is very low.  So, your options are: (1) run the V3 analog out to the R4, with no attenuators.  keep the V3's levels very low, below the 2nd LED light. or (2) use a -20dB attenuator.  with that in between the V3 and the R4, you'll be able to output a max analog signal of +24dBu from the V3, which will then be attenuated down to +4dBu before it gets to the R4.  The V3 outputs a +25dBu signal when the V3's A/D clips, so as long as you stay one dB below clipping on the V3's digital level meter, you'll be fine on your R4 levels.

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Stay on line in with the R4, and consider using -20db inline pads on the way into the R4. The problem arrises in how the levels on the V3 are represented visually and what it's pumping out are not the same.

Read here for more info and a handy graph (seriously, I should bookmark this, I've had to reference it at least twice in the last 2 months). You'll need to look up what the max signal is on the R4, but I bet it's around +4db.

the part of your quote that I bolded isn't quite true.  The meter on the V3 is a very accurate representation of the digital levels after the signal goes through the V3's A/D. 

Yeah, I failed to mention that what it's pumping out [in this instance due to the R4] are not the same. I can haz cludgy post, thanks for the addendum.

[goodcooker]

I used to run V3 analog> R4 all the time. You def need to keep R4 inputs on line in and put at least a 20dB pad in between. I built a pad into a pair of XLR interconnects that matched the V3 meters to the R4 meters. It was approx 23 dB of attenuation. The plans for building the pad in an xlr are around this site somewhere thanks to rowjimmytour.

[Weirdness]

Cool, thanks a lot for the info guys!   

[SmokinJoe]

In a related note...  I run V3 > analog > R4 a lot too, and my R4 happens to be a "Busman Hybrid", with Transparent mod on channels 1/2 and "Vintage Mod" on channels 3/4.   I routinely run the Mics>V3 into the Tmod channels and SBD into the Vintage/Warm channels.  The Busman mod drops the sensitivity of the T4 line input significantly, to the point where I don't use attenuators.

I've run this way dozens of times... and I have have a system that works for me.   I run R4 Line in, gains turned all the way down, and my objective is to keep the V3 below -6... Since the first RED light on the V3 is -9, that is what I shoot for... just the occasional blip on the first RED light... I typically bring the whole thing up by 3db or so in post, to me that is just enough headroom to be safe.  This way I get to pay attention to the V3 meters (which I like) and pay less attention to the R4 meters (which I don't like).

In a related note... for my MR1 I built some balanced XLR > 1/8 TRS cables with 20db attenuation, and then I run the MR-1 at -4.5db, and watch the V3 meters.