ProFire 2626 Line input levels are quite low

[mlange]

Hey all 2626 owners.....

My unit reads -18VU within ProTools on a +4dBu line level signal inputted to any of the 8 TRS channel inputs. We've tried mono and TRS cables from variety of line level signal sources & test gear and the results are always the same.... an enemic signal level at -18VU.

As there's no adjustment the line levels' inputs, has anyone else run a line level signal and checked their 2626's performance? When we took the same configuation and used a Firewire Audiophile, it properly reports a -1.7VU with +4dBm applied to it's line input.

Thanks

[mlange]

Nobody got a chance to record a line-level signal into their 2626?

[detroitkruk]

have you called m-audio?...i'd really like to know how this goes...was looking at the light bridge then turned my attention to the 2626...

please keep us posted in this thread...i know alot of people simply don't own these yet...

detroitkruk

[tash]

-18VU, not -18dbFS on the digital scale? If it reads -18dbFS on your pro tools, it doesn't sound too low to me. I don't know what is the maximum input level of the line input for the unit. The tech guy from M-Audio told me it's all in the spec.

Every unit/maker has different value. To me it's not a surprise a gear like profire 2626 has maximum input level between +16~22dbu. If it's the case, -18dbFS (sorry if you mean -18dbu) is not low. You don't want the siganl to be too much hotter than 0dbu (probably equivalant to -16~-22dbFS). If it's close to 0dbFS, it's way way too hot.

maximum input for A/D and maximum output on the same unit for D/A are not alwasy the same, either.

[mlange]

-18VU, not -18dbFS on the digital scale?

Hey Tash -

Yep, it's -18VU, not dbfs

Can anyone else try this? Just slap a line-level signal into the 2626 and check your VUs in PT ......

[theaero]

Anyone figure out whats going on? I ordered one of these 2626s and I wanna make sure the line ins work right..

[mlange]

Where are you reading -18VU?

The meters in Protools measure dBFS

It sounds like the level from the PF2626 is spot on

+4dBm = -1.7VU???

There is nothing proper about that measurement. dBm is a measurement of power (milliwatts) and is not used to compare to dBFS. A decibel measurement referenced to voltage is used instead, dBu or dBV.

The line inputs on the Audiophile expect to see a nominal level of -10dbV (0.316 Vrms) so as to interface with consumer hi-fi gear.

The +4dBU (1.23 Vrms) referenced signal you are using is too hot for this device.


+4dBu = 0dBVU = -18dBFS

+4dBu = 0dBVU = -18dBFS .... EXACTLY!! -18VU = -36dBFS!!

Sorry - my bad on the input level previously mentioned - it wasn't +4dBm on the Audiophile.... we would switch the output level of our signal generator between +4dbu & -10dBv.

The real point I'm trying to convey is that while the Firewire Audiophile can accept signals up to and above 0VU within ProTools, our 2626 CANNOT OVERLOAD A CHANNEL INPUT WITHIN PROTOOLS VIA IT's LINE LEVEL INPUTS. We pretty much "max-out" around -18VU, or -36dBFS.

And this is not only on our 2626.... one other 2626 user who's checked has really low levels, too.

[tash]

What do you mean by -18VU? -18dbu? Which metet are you using to measure it and how is it calibrated?

I don't own the unit though I am interested in it.

I just checked the 2626's spec on M-Audio's website. It says 'Maximum input level +19.6dBu, typical' for Line-input.

If you mean -18db on Pro tools digital meter, it's probably equivalant to +1.6dbu on the analog scale and it is hot enough (it's over 0dbu).

And you can't compare two units especially a more professional one with a more consumer type model.

I'm not familiar with audiofile firewire either, but take the spec of firewire solo on thier website for example.

It says +2.2 dbV. It is approximately +4.42 dbu. So for this unit, around -4.42db on the digital scale (dbFS) is 0dbu.

When you feed the same signal that would read -18db on your Pro tools with your 2626 could read like -2.82db on the same pro tools with firewire Solo ( I know this is not your unit)

If you use analog VU meter plug-in, you need to calibrate it to a different setting according to the unit you use it with. Otherwise, the same input level would read totally different on the digital scale though if it's measured outside the digital world it always read the same.

If I'm totally misunderstanding you, pardon me.

[mlange]

Tash-

0VU within ProTools = -18dbfs

My concern right now is that the 2626 reads a +4dbv balanced line-level signal as -18db VU within ProTools...... that's -36dbfs, and that's far too low for my tastes.

I've got racks of outboard gear that have been able to drive every i/o I've ever thrown at them (balanced or unbalanced - pro or consumer), and suddenly this one product cannot. I typically record as healthy of a signal level as possible, but using the 2626's TRS inputs, balanced or unbalanced, yields a very low, low level. Colour-wise for the PT channel metering, low greens.... never yellow.... certainly never red!

Why is this important? I'm using the 2626's A-Ds with other external mic pres, and don't want to push those pres into a bunch of unnecessary gain. Never had to with any other A-D before (some really spendy stuff, too).

All that's needed is for a couple of 2626 users to confirm or deny their input levels' performance on the line-level side of their units. If it's just mine - great! If it's not ....

Finally, I do understand how to use the signal generator and it's calibration, but thanks for pointing it out. You're right - it's quite easy to make a mistake in the setup and configuration.

[tash]

Well. If you're talking about Pro Tools' own digital meter, its scale is dbFS. So it it reads -18db on Pro Tools it is -18dbFS. It won't be -36db.

For your unit, -18.00db on Pro Tools = +1.6dbu on the analog scale.

Sorry I just don't get 'VU WITHIN pro tools' part. English ain't my native toungue.

If it's 'dbVU', then you must be using some plug-ins or analog meter because Pro Tools itself uses 'dbFS' like any other DAWs, though?

Only way if it's your unit or it's by the design, contact M-Audio or have it checked by the store you bought it.