An Audio Tool That Should Be in Every DAW. VU Meter is a standalone analog audio tool that helps monitor recording levels. This resizable, alternative PPM style meter works on Windows 7/Vista. The tool helps you attain enough headroom, optimal levels and a much clearer mix in your DAW. A stereo correlation meter rounds out the trio, giving you insight into the left/right phase relationship of your signal. Available in Native Effects, VST3, AU, and AAX formats, VU Meter will let you analyze your signal levels like never before and it's our gift to you for being an audio nerd, just like us. Windows VU Meter is a standalone application that mimics an old stereo's VU or audio level meters. Taste me matte lipstick. The program has no intervening toolbars or window frames to allow the program to allow a clean. 2U Stereo VU Meter. Large Stereo VU Meter in a 2U package. A real VU meter with attenuator and LED backlights. VU meter mounted in an oak case for desktop applications. I love these VU meters! They're really useful and they look great in my studio!
A volume unit (VU) meter or standard volume indicator (SVI) is a device displaying a representation of the signal level in audio equipment. The original design was proposed in the 1940 IRE paper, A New Standard Volume Indicator and Reference Level, written by experts from CBS, NBC, and Bell Telephone Laboratories.[1] The Acoustical Society of America then standardized it in 1942 (ANSI C16.5-1942)[2][3] for use in telephone installation and radio broadcast stations. Consumer audio equipment often features VU meters, both for utility purposes (e.g. in recording equipment) and for aesthetics (in playback devices).
The original VU meter is a passive electromechanical device, namely a 200 µA DC d'Arsonval movement ammeter fed from a full-wave copper-oxide rectifier mounted within the meter case. The mass of the needle causes a relatively slow response, which in effect integrates or smooths the signal, with a rise time of 300 ms. This has the effect of averaging out peaks and troughs of short duration, and reflects the perceived loudness of the material more closely than the more modern and initially more expensive PPM meters. For this reason many audio practitioners prefer the VU meter to its alternatives, though the meter indication does not reflect some of the key features of the signal, most notably its peak level, which in many cases, must not pass a defined limit.
0 VU is equal to +4 dBu, or 1.228 voltsRMS, a power of about 2.5 milliwatts when applied across a 600-ohmload. 0 VU is often referred to as '0 dB'.[4] The meter was designed not to measure the signal, but to let users aim the signal level to a target level of 0 VU (sometimes labelled 100%), so it is not important that the device is non-linear and imprecise for low levels[according to whom?]. In effect, the scale ranges from −20 VU to +3 VU, with −3 VU right in the middle. Purely electronic devices may emulate the response of the needle; they are VU-meters in as much as they respect the standard.
In the broadcast industry, loudness monitoring was standardized, in 2009 in the United States by the ATSC A/85, in 2010 in Europe by the EBU R-128, in 2011 in Japan by the TR-B32, and in 2010 in Australia by the OP-59.
Lead[edit]
The original designers of the VU meter were tasked with finding a way to measure complex audio signals with a simple technology.
Since a VU meter is a mechanical device, it can never reflect the instantaneous signal peaks of complex audio signals. The designers of the VU meter therefore took a different approach. They created a meter that did not measure peaks, but simply inferred them. A real VU meter has a very specific 'ballistic characteristic'. This means that it responds to changing audio signals at a very precise speed, rising from no signal to 99% of '0 VU' when a 1 kHz sine wave tone is applied for 300 milliseconds.
Morrowind official site. When using a VU meter, the audio system is calibrated with a sine wave tone at a 'reference level' for the system. At the reference level, the VU meter shows '0' for a sine-wave tone, but the engineer must know that, with music or speech, to always infer that peak levels are always between 6 dB and 10 dB higher than the reference level. The usefulness of the VU meter comes from the fact that for most types of audio sources the system engineer can count on these peaks being within this range and can design the audio system with confidence. Good engineering practice is to always build in a little extra 'headroom', as it is called, to cover the strange conditions where an audio signal might exceed normal peak levels or the equipment operator fails to adjust the levels correctly. Typically the levels considered when designing systems using a VU meter are:
- Reference level (typically +4 dBu, valid with tones only);
- Standard output level (10 dB above reference, typical peak levels);
- Clip level (6 dB above standard output level, 'headroom' to allow for unusual conditions)[5][6]
Standard characteristics[edit]
The behaviour of VU meters is defined in ANSI C16.5-1942, British Standard BS 6840, and IEC 60268-17.
Reference level[edit]
VU defined:
'The reading of the volume indicator shall be 0 VU when it is connected to an AC voltage equal to 1.228 Volts RMS across a 600 ohm resistance (equal to +4 [dBu]) at 1000 cycles per second.'[7][8]
Note: The reference above is generally true now and was always true in the recording industry. However in some North American broadcast installations up until late in the 20th century, the Reference level ('0VU') was +8dBm at large studio installations and some used 150 ohm impedance throughout the studio.(CFRB Toronto and CFPL London Canada) This was yet another 'standard' established in the early years of audio and the VU meter was altered by changing the series resistors to adjust its sensitivity. This had no effect on the ballistics. [9]
Rise time[edit]
The rise time, defined as the time it takes for the needle to reach 99% of the distance to 0 VU when the VU-meter is submitted to a signal that steps from 0 to a level that reads 0 VU, is 300 ms.
The overshoot must be within 1 to 1.5%.
The fall time is the same as the rise time, 300 ms.
Frequency response[edit]
The level specification is meant at 1000 Hz. The reading should not depart from the reading at 1000 Hz by more than 0.2 dB from 35 Hz to 10 kHz or more than 0.5 dB between 25 Hz and 16 kHz.
Note that the specification mentions only sinusoid waveforms. Given the electromechanical principle of the meter, the deviation of the needle is actually approximately proportional to the average of the part of the signal with more than approximately 0.4 V instantaneously because of the two copper-oxide rectifiers always in series, which transfer function curve has a knee around 0.2 V. Signals generally do not have a sinusoidal waveform by far, even if they all fall within the VU-meter bandpass. The reading is the average of the voltage,[10] and is not an indication of the power of the signal, which is proportional to the average of the square of the voltage, or the root-mean-square (RMS) value. As a conventional VU reading, however, it served its purpose as an indication a) of the overall level and dynamics of the signal and b) of the proximity to the maximum admitted level, to the operators of recording and broadcasting equipment. Maintenance staff could also use it as a measurement apparatus, to check for losses in transmissions and level alignment, provided that they used exclusively sine waves as test signals.
Impedance[edit]
The VU meter and its attenuator should present a 7,500-ohm impedance to the circuit it is applied to, measured with a sinusoid signal that sets the indicator to 0 dB.
History[edit]
The VU-meter was originally developed in 1939 by the combined effort of Bell Labs and broadcasters CBS and NBC.[11] In the 1970s–80s, neon-filled, planar dual display dekatrons with up to 201 segments per stereo channel[12] were popular among broadcasters as fast bar graph VU meters.
Other level meters[edit]
The consumer audio industry often uses volume indicators that do not comply with any standard.[13]
BBC sound engineers would refer to the VU meter as the 'Virtually Useless' meter,[14] preferring the PPM.
Academic research has shown that a SVI or VU meter behaves differently to the average value and RMS meters. The ballistics shown by this instrument in response to signals with large crest factor position its readings halfway between both. For example, an increment of 3 dB in the crest factor of an audio signal gives approximately a fall of −3 dB in a RMS meter, −6 dB in an average meter, and −4 dB in a VU meter.[15]
See also[edit]
References[edit]
- ^Chinn, H. A. 'A New Standard Volume Indicator and Reference Level'(PDF).
- ^McKnight, John. G. (Jay) (2006-07-27). 'Some Questions and Answers on the Standard Volume Indicator ('vu meter')'(PDF). Audio Engineering Society.
- ^'VU Meters Information'. Engineering 360. Retrieved 2017-03-23.
- ^VU Meter.
- ^Schmid, Hans (January 1976). 'Audio, The Stepchild of Television Broadcasting'. SMPTE Journal. 85: 6–9. doi:10.5594/J07600.
- ^Schmid, Hans (March 1977). 'Audio Program Level, The VU Meter, and The Peak Program Meter'. IEEE Transactions on Broadcasting. BC-23 (1): 22–26. doi:10.1109/TBC.1977.266233. S2CID40700960.
- ^volume unit or VU
- ^[1] Re: -dBm?
- ^ Source: the author worked on these systems and with the designers in the 1970s
- ^Average Voltage Tutorial
- ^Robjohns, Hugh (July 2013). 'What's the difference between PPM and VU meters?'. Sound on Sound.
- ^'Plasma Panel Displays - Dual Linear Bar Graph'(PDF). Vishay Dale, Columbus, Nebraska, USA. November 2000. Retrieved 8 March 2014.
- ^Meter MadnessArchived 2015-04-02 at the Wayback Machine – Mike Rivers.
- ^'On audio equipment, sound level meters are sometimes called VU meters. What does VU stand for?'. Guardian News and Media Ltd. 2011. Retrieved 8 August 2019.
- ^Method to Evaluate the Ballistics of Audio Meters – Victor M. Acuña.
External links[edit]
| Wikimedia Commons has media related to VU meters. |
- A New Standard Volume Indicator and Reference Level by Chinn, Gannett & Morris
A large, real VU meter with precision Sifam units and LED backlights. Designed for modern workflows so you can concentrate on the music and not on metering:
- Large, proper VU meter with Sifam VUs for accurate metering
- LED backlighting so it's easy to read in any studio
- Built in stepped attenuator, means they work perfectly with any studio level
- Easy to connect, calibrate and adjust
- Fit into any 2U space, or place onto a surface with the optional oak case
There's something very reassuring about a solid hardware VU meter.
Whether it's the warm yellow colour of the backlights or the smooth movement of the VU needles, a proper VU reeks of professionalism and music. However they're not easy to find these days. Thankfully Crookwood have improved on the original VU design to make it a unique and powerful tool in your studio.
The first and most important ingredient is the VU unit itself. We use real, large Sifam VU units, as used the old analogue SSL, Neve and Focusrite consoles. These mechancial meters work by virtue of their precision construction and they're light-years away from the typical consumer and copy-cat units used elsewhere. You can trust what they're telling you with real music as well as static tones.
Then we designed our own LED backlights, using LED arrays to give a solid colour backlight to the meter for use in low light environments. We added our own lighting gel filters to get a really pleasing yellow colour, reminiscent of the old Sifam festoon bulbs, but without the bulbs associated heat and short life.
Our LEDs are rated at over 10,000 hours, so you'll keep working for longer.
Lastly we added a precision stepped attenuator, unique to us, so you can adjust the level to the VU's so that they're always working within their range, no matter how hot the signal is, or how compressed or not the music is. This feature makes these VU meters really useful with modern signal levels.
So no matter how hot your signal is, these VUs will work perfectly.
Because today, in the midst of a plethora of modern digital meters, the VU meter still has a solid place. In fact for many situations it is preferable to a digital meter for everyday metering.
This is because it is really good at displaying average loudness, but unlike a digital meter, you can just glance at it to see the level. In contrast, digital meters sit in your eyesight, demanding your attention and taking your attention off the music (we've written a large article about this here: https://crookwood.com/blog/the-beauty-of-vu-meters/)
In short, our VUs let you concentrate on the music, not on the metering.
To make connecting easy, the meter has XLR inputs feeding a high impedance balanced input buffer. This allows you to connect the meter to virtually any source, including unbalanced consumer type outputs, without altering the level, or loading the source. It's also easy to fit to a monitor controller that doesn't have a dedicated meter output.
A mechanical VU meter will drift over time and will need to be re-calibrated occasionally. For this reason, we've made the meter open at the back, so you can access all trimmers easily while still powered up and connected. All electronics are sealed however for protection.
Finally for users with no rack space left, we can provide an English Oak wooden surround for the meter, so it can be mounted, freestanding on top of a surface.
Stereo Vu Meters
Whether it's rack mounted or freestanding, our VU meter will improve your audio experience.
- Easy to mount, 2U 19″ package
- Two big VUs, 105mm (4″) across
- VUs conform to BS6840:part 17 1991 & IEC268-17:1990, apart from attack time which is slightly over compensated
- Stepped attenuator offers attenuation of 3, 6, 9, 12 & 15dB.
- LED backlights, with 10,000 hour rating
- 40KΩ input impedance for easy connection to balanced or unbalanced outputs
- Balanced XLR inputs on rear of box
- 12V DC powered. External power supply is provided and has a 1M long lead
- Open frame rear for easy access, only 80mm ( 3″) deep
- Optional wooden case is handmade from English Oak
American Audio Vu Meter
- Meter is GBP 365, ≅ Euro 425 , or US$ 508
- Optional Oak case is GBP 115, ≅ Euro 134 , or US$ 160
- All prices are excluding shipping and VAT.
- Contact us for a quote with shipping to your country
