Unity Gain Calibration on the V-Studio 700

Author
znball
Max Output Level: -90 dBFS
  • Total Posts : 20
  • Joined: 2007/11/26 19:15:05
  • Location: Hercules, California
  • Status: offline
2013/01/02 20:13:21 (permalink)

Unity Gain Calibration on the V-Studio 700

Has anybody ever did a Unity Gain Calibration on the V-Studio 700 system. If so, I would like to know if it's needed and next if so, how did you do it, or if there is any instructions written anywhere on how to perform the procedure.

Ron Ball   
  Sonar X2a Producer 64Bit,  All PC Modules, Softube Mix Bundle,  Sonar VS-700, Computer: Sweetwater Creation Station 450, Win 7  64Bit, 24 Gb Ram, (3) 1TB Drives
#1

6 Replies Related Threads

    Crg
    Max Output Level: 0 dBFS
    • Total Posts : 7719
    • Joined: 2007/11/15 07:59:17
    • Status: offline
    Re:Unity Gain Calibration on the V-Studio 700 2013/01/03 13:40:38 (permalink)
    What exactly is that znball?

    Craig DuBuc
    #2
    Jeff Evans
    Max Output Level: -24 dBFS
    • Total Posts : 5139
    • Joined: 2009/04/13 18:20:16
    • Location: Ballarat, Australia
    • Status: offline
    Re:Unity Gain Calibration on the V-Studio 700 2013/01/03 15:21:05 (permalink)
    It is a good question and involves a few areas in order to calibrate the system.

    The Ref Level

    This is the chosen level to which will produce an analog audio output voltage of +4 dBu (1.23 v) at the output terminals as measured by a digital multimeter in AC volts rms mode. Looking at the specs for the VS700R it seems that is -18 dB FS. There are various other digital ref  levels such as -12, -14 and -20. I work with a Yamaha digital mixing system that is calibrated for -14 dB producing +4 dBu at my main outs. It can be easily switched over to -20 now being more common.

    An alignment tone is created at -18dB (400 Hz or 1KHz) being the level that represents the tops of the sinewave peaks. Track levels, buss and master buss faders should be at 0 dB or unity setting. No effects plugins or any plugins  on tracks or busses. I prefer stereo ref tones being played back on a stereo track. It avoids any pan law effects.

    If this is played in your DAW you should see +4 dBu at the main outs of the VS700R. This is measured across the balanced output. With a ref level of -18 it means the output has a maximum output level and that is +22 dBu which is excellent. This is still a clean sinewave output before any clipping is visible.

    It is good to have a VU meter plugin inside the DAW and monitoring the Main Output with the output showing 0 dB VU when the alignment tone playback is at -18dB.

    Input Levels

    Now we can see what range of input levels are required to create this same ref level at the main outs. An oscillator with a digital volt meter measuring its output level is set up and connected into the various inputs of the VS700R. The specs say the input range is from -60dB (0.775 mV) to +4 dbu (1.23v) which is a hefty range.

    With the PAD on, minimum gain at the input a +4dBu (1.23 v) input signal should produce the reference level inside the DAW while input monitoring and the correct level at the main output again. With the input gain up to maximum and the Pad off a signal level of -60 dBu (0.775 mv) at the mic inputs will also produce the same ref level inside the DAW and hence at the output again at +4dbu. (1.23v)  

    Conclusion

    This applies to any DAW system not just the VS700R. It is simply a matter of identifying what the ref level is going to be. -18 is a very common level but Bob Katz says that -20 dB is also a good ref level and is in line with movie soundtrack levels and specifications. It also means if you are monitoring at 85 dB SPL while the ref level is at -20 dB then you have the potential for the audio system to cleanly go up a full 20 dB to 105 dB SPL and still without any clipping. It also means transients can be 20 dB high creating very clear, fast sounding attack transients in percussion instruments for example.

    A lot of commercial music is heavily mastered to average rms levels around -7 and -6dB. While this produces a very high output signal level the dynamic range is also limited to that same amount ie 6 dB which ain't much!

    It is a good thing to calibrate your system and beware of the signal levels flowing in and out of your system and how they relate to the ref level inside the DAW system. Many of us have software that is connected to our audio interfaces and some if it is quite complex in terms of signal routing and level changing operations. It is also good to know that signal levels are going in and out of that software. 

    You can at least start your recording projects at a -20 dB ref level and also at 24 bit for maximum fidelity to begin with anyway. The mix can also still be at this same ref level. Having an un mastered -20 dB ref level mix is good to have. Then after mastering is applied the average rms level will increase accordingly, dynamic range reduced and bit depth/sample rate if applicable also reduced to lower resolutions for distribution.

     



    post edited by Jeff Evans - 2013/01/03 17:43:44

    Specs i5-2500K 3.5 Ghz - 8 Gb RAM - Win 7 64 bit - ATI Radeon HD6900 Series - RME PCI HDSP9632 - Steinberg Midex 8 Midi interface - Faderport 8- Studio One V4 - iMac 2.5Ghz Core i5 - Sierra 10.12.6 - Focusrite Clarett thunderbolt interface 
     
    Poor minds talk about people, average minds talk about events, great minds talk about ideas -Eleanor Roosevelt
    #3
    znball
    Max Output Level: -90 dBFS
    • Total Posts : 20
    • Joined: 2007/11/26 19:15:05
    • Location: Hercules, California
    • Status: offline
    Re:Unity Gain Calibration on the V-Studio 700 2013/01/03 21:01:04 (permalink)
    Thanks Jeff, This is exactly what I was looking for, and in very precise detail. I was wondering in all the forum posts and instructional set-up material, or manuals, I have never seen any mention of setting up Unity Gain Calibration. I was wondering what are the users doings. Thanks again for your expertise.
     
     
    #4
    listen
    Max Output Level: -79 dBFS
    • Total Posts : 593
    • Joined: 2008/09/12 06:07:55
    • Status: offline
    Re:Unity Gain Calibration on the V-Studio 700 2013/01/03 21:41:47 (permalink)
    Jeff Evans thank you so much for this post - will you be my MENTOR????
    Like for real...

    - Listen -
    FOH Mixer & Recording Studio Manager
    Nothing but the grace of God - mggtg.



    VS 700C - R / CONSOLE 1 / NEVE PORTICO 5017 / TASCAM UH-7000 / SONAR PLATINUM  / REASON RECORD 9 / VMP 2 / UREI 7110's / UA LA-610 MkII / AUDIENT ASP 880 / CREATION STATION 450 V 5 WINDOWS 10 / HOME 64 - BIT / SKYLAKE CORE i7 (i7 - 6700, 4 CORES/8 THREADS)
    #5
    Jeff Evans
    Max Output Level: -24 dBFS
    • Total Posts : 5139
    • Joined: 2009/04/13 18:20:16
    • Location: Ballarat, Australia
    • Status: offline
    Re:Unity Gain Calibration on the V-Studio 700 2013/01/03 22:13:06 (permalink)
    Thanks it is a pleasure. I just wanted to add something in regards to what happens if you are playing back a ref test level and you are not seeing +4 dBu at the output of your system. 

    Using any ref level test tone it is possible to determine at what ref level any system is calibrated at. If you play back a ref level of for example -18 dB and the output might not be +4 dbu (1.23v) It might be 0 dBu (0.775 v) But this is 4 dB short so that system is actually setup for -14 dB as the +4 dBu output level. 

    Simply adjust the channel fader to get +4 dBu on the output. Note how far either you have to add or subtract to your ref test level on the track (in this case is -18 dB) to bring the output to +4dbu. Just create a new ref test level accordingly and you will produce +4db when your system is playing it back.

    We have just had an SSL AWS948 desk installed at my teaching location. 

    http://www.solid-state-logic.com/music/aws/

    So our -18db tone produced +6 dBu instead of +4 dBu on the main outs. (meters were showing +2 dB high) Meaning desk was set to -20. A new alignment tone at -20 set everything straight again.
    post edited by Jeff Evans - 2013/01/04 16:19:22

    Specs i5-2500K 3.5 Ghz - 8 Gb RAM - Win 7 64 bit - ATI Radeon HD6900 Series - RME PCI HDSP9632 - Steinberg Midex 8 Midi interface - Faderport 8- Studio One V4 - iMac 2.5Ghz Core i5 - Sierra 10.12.6 - Focusrite Clarett thunderbolt interface 
     
    Poor minds talk about people, average minds talk about events, great minds talk about ideas -Eleanor Roosevelt
    #6
    bnova
    Max Output Level: -90 dBFS
    • Total Posts : 33
    • Joined: 2010/02/07 11:37:38
    • Status: offline
    Re:Unity Gain Calibration on the V-Studio 700 2014/01/11 19:04:14 (permalink)
    Hi Jeff
     
    Appreciate the info above. I am still struggling a little getting my system set up properly with gain. I have a Toft Audio ATB 24 console that I have connected to two VS700R's through the Tofts Direct Outs(Balanced TRS 1/4"). I set my levels on my Toft like I normally do to record my drum tracks. Since I have the direct outs of the toft going to the 1/4 inputs on the VS700R should I be using the -20db pad? If I turn the pad off the signals are immediately to hot and no matter how far I turn the gain down on the VS700R it is still hitting the red level bar. If I use the pad then I have to boost the gain of the VS700 pres. What am I doing wrong?
     
    Thanks
     
    Mike in Atlanta GA
    #7
    Jump to:
    © 2024 APG vNext Commercial Version 5.1