FuzzMeasure
FuzzMeasure Pro is an audio and acoustical measurement application used to create, produce, and analyze visually stunning graphs of your measurements. Using FuzzMeasure’s tools you can easily gather measurements of a home theatre system, recording studio, stage, auditorium, raw loudspeaker components, and more. FuzzMeasure is a useful, trial version program only available for Mac, that belongs to the category Audio & Video with subcategory Plug-ins Libraries & Effects. Alienware area-51 alx x58 driver download for windows. More about FuzzMeasure Since we added this program to our catalog in 2006, it has managed to obtain 3,767 downloads, and last week it achieved 6 downloads. FuzzMeasure is an acoustic measurement tool specifically constructed for Mac computers, so I decided to give it a go; see how it worked, and how it helped me in my quest for better room acoustics. Akai professional amx driver download. To be able to use FuzzMeasure, you need the right equipment. Grammy Award winning Engineer & Producer, Composer & Sound Designer for Film, Theatre & Television, Tony David Cray, tells us about his experiences using Fuz.
By Ethan Winer (EW) of RealTraps and Nyal Mellor (NM) of Acoustic Frontiers
Room Measurement Software
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The importance of room acoustics is often overlooked, even by those who consider themselves serious listeners. People who obsess over vanishingly small amounts of distortion or frequency response errors in their gear accept response deviations of 30 dB or more added by their room. Often they have no idea how bad their room really is! This graph shows the low frequency response measured in a typical small living room:
| Figure 1: This is the low frequency response you can expect in a room without any bass traps. |
But a skewed frequency response is only one of the problems caused by poor room acoustics. Rooms also resonate and ring, sustaining some frequencies longer than others. If you clap your hands in an empty bedroom you can hear the pitched 'boing' sound caused by reflections bouncing repeatedly between opposing surfaces. The pitch of the boing is related to the distance between the boundaries. The same thing happens at bass frequencies, but hand claps don't have enough low frequency content to excite the resonances. The resonances are still there, and they damage bass clarity, but you need an appropriate test signal to measure them.
Even if the steady state room response were perfectly flat, if 1 KHz sustains for half a second longer compared to other frequencies, the perceived volume at that frequency will be higher due to the additional energy over time. So one important metric for room measurement is decay time versus frequency. The goal is for decay times to be more or less uniform over as wide a range as possible. In larger rooms, excess reverb and ambience cloud detail, and in smaller rooms 'early' reflections - those arriving at your ears within about 20 milliseconds of the direct sound - have a similar effect. Besides obscuring detail, early reflections also create a particular type of response error called comb filtering. Indeed, all acoustic problems are caused by reflections off the walls, floor, and ceiling.
I separate room acoustics - both measurements and treatment - into two frequency ranges: bass below about 300 or 400 Hz and mid/high frequencies above 400 Hz. For low frequencies it's important to see as much detail as possible. This means measuring and displaying the response at high resolution in order to see the true extent of peaks and nulls. This next graph shows the exact same measurement at two different resolutions:
| Figure 2: Standard 1/3 octave averaging hides a lot of detail, as you can see when the same data is displayed at 1/12 octave resolution. |
At mid and high frequencies it's more appropriate to use averaging. Small changes in microphone placement have a huge effect on the measured response. A graph of the high frequency response that is not averaged is riddled with so many peaks and nulls it's difficult to see the forest for the trees, so to speak.
Why we measure
Many people believe that room measuring is needed to know how to approach treating a room, to determine the number and placement of bass traps, mid/high frequency absorbers, and diffusors. But in most cases you can treat a room effectively without measuring at all. The basic goal is to put bass traps in the room corners, mid/high frequency absorbers at the side-wall and ceiling reflection points, and optionally absorbers and/or diffusors on the rear wall behind the listener. Treating the rear wall is more necessary when that wall is closer than ten feet behind your head.
Originally, I got into room measuring mainly to show people how terrible typical rooms are. As I said earlier, most people have no idea how badly their room damages sound quality. They worry whether their loudspeakers are flat, while ignoring how much worse the response is made by their room. Of course, measuring is useful to assess the improvement after adding treatment, and to compare the benefit from different acoustic panel placements. It's also useful to see if more treatment is still needed, and at what frequencies the problems remain.
What we measure
The two main things we measure are raw frequency response as shown in Figure 1 above, modal ringing and reverb, and impulse response. Ringing is similar to reverb except it sustains some frequencies more than others. If you sing different notes in a large space like a church or auditorium, all of the notes will decay at more or less the same rate. In small rooms the decay times become much more frequency-dependant, especially at low frequencies. To view ringing decay time we use a 'waterfall' graph like this:
| Figure 3: The graph above is derived from the same data shown in Figure 1, but this graph also shows modal ringing and the decay times. |
In this type of graph the 'mountains' come forward over time, and represent resonating peaks in the response. When some bass notes played in a room sustain longer than others, they will seem louder, and indistinct, creating the effect known as 'one-note bass.'
The last type of graph shows the impulse response, which lets you see the timing and strength of individual reflections. We'll get to that later in this series, along with graphs that show reverb decay times versus frequency.
In this introduction I explained the errors introduced by all untreated rooms. Once you know the audible problems a room causes, you then know what needs to be measured. And once you know what is being measured, you can better understand what the graphs displayed by room measuring software mean. Top
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| By Dan FitzGerald I have noticed that quite a number of people are beginning to use Software and Measurement Microphones to analyse their listening spaces. The immediate results can be confusing and disappointing. To get the best from a Room Analysis Tool, some skill and understanding is essential. This is intended as a simple primer on how to do it, and how to view the results. WHAT TO EXPECT No miracles! It is unlikely that you will get beautifully flat frequency response curves. I find the software is best at showing changes rather than describing a static situation. It excels at comparative jobs, such as finding the best speaker and listener positions by trial and measurement. Frequency response is the most common and easily understood graph. There are other powerful ones also. Particular frequencies or bands of frequencies which ring on longer than their neighbours will cause particular notes or tones to stick out, blurring music or speech. This behaviour can be seen very graphically on the waterfall plot in Figure 1 at left which has three axes. Top |
'I recommend an omni studio recording microphone, or a Sound Level Meter (SLM) with a line level audio output socket.' 'A sound absorbent panel, temporarily held in place can nuke these problems, also showing exactly where to put treatment.' 'I tie a thread with a small weight to the microphone. Positioning the dangling weight over the marked floor spot guarantees repeatable location and height.' | The third axis describes time passing starting from zero at the back. Consider the spectrum at zero as the instant when the noise is suddenly turned off. The 'slices' coming towards the viewer are spectra taken at later instants. An ideal room would have very even decay, longer at low frequencies, gradually shortening towards the highs. This 3-dimensional picture is worth a thousand words to the experienced eye. Reverb Time (aka RT60, EDT, T20, T30) can be displayed in octave or third-octave bands as simple bar graphs. Given time and experimentation, one learns how to interpret these different ways of visualising the room sound. Changes, however, can always be immediately seen and appreciated. Anydata usb mtp device driver download for windows 10. THE MICROPHONE I believe the type of Microphone does not particularly matter for our purposes. I have used the built-in mic on Laptops and iMacs. Omni is best but not vital. Rather than buy a 'measurement microphone' I recommend an omni studio recording microphone, or a Sound Level Meter (SLM) with a line level audio output socket. This socket has a pre-amplified output from the SLM's in-built microphone. I would go for a modern SLM with a large screen rather than the Radio Shack model. Sound level meters have many secondary uses and benefits. Also see the article Measuring Microphones. MEASUREMENT AND EVALUATION TOOLS ETF 5 is a PC program which most directly addresses our needs. FuzzMeasure Pro is a similar product for the Mac. There are many other analysis tools, from free to extremely expensive. I use several simultaneously to achieve a holistic evaluation of the room. Here are some other tools that I find invaluable:
Our body can generate tones of varied pitch and duration. Uniquely, this human tone generator can move about the room, tuning in and stimulating hot spots. Humming, barking, or grunting at varied pitches can provoke the booms, honks, and rings, and identify exactly where they are. Labmeter linked above will show the frequency. You might want to be alone when doing this! A sound absorbent panel, such as a RealTraps MiniTrap or MicroTrap, temporarily held in place can nuke these problems, also showing exactly where to put treatment. Lastly, a caveat - some software graphs allows clicking on, say a peak, to identify it's frequency. These seemingly exact frequencies are not always correct due to internal math resolution. I wouldn't use them to set a Room EQ for instance. Top HOW TO DO IT I am assuming a rectangular room, with speakers at the narrow front wall. Identify the zones at 3/8 (38%) of room length from the front wall and ditto from the back wall. These zones mathematically have the best balance of room modes and should sound best. Another rule of thumb suggests there is little bass at the room centre. These are useful, often correct, guidelines. However, measurement always trumps theory. Using masking tape, label the floor at all significant listening spots such as the engineer's seat, the producer's seat, and the rear couch. Use descriptive names and numbers for your chosen spots. My software uses one speaker at a time during measurement sweeps, so I use names like L38FC (Left Speaker Front Centre), L38BL (Left Speaker Back Left), and so on. Establish your own system and stick to it. Eight spots seems appropriate in a small room. Mount the microphone or SLM on a stand or tripod. Seated ear height is good. If you use a mixing desk and like to prowl around, then use standing ear height. Mix and match heights if you like, but remember to use fully descriptive labels. I tie a thread with a small weight to the microphone. Positioning the dangling weight over a spot marked on the floor guarantees repeatable location and height. I point the microphone directly at the tweeter. 45 degrees or straight up is more usual Stateside. Whichever you chose, do keep it consistent. A human body close to the mic causes strong midrange anomalies. So stay at least a meter away from the microphone. When measuring, the software generates very loud noises. Wear earplugs or closed headphones. Start at low volume, try a couple of measurements, increasing the volume until you feel the room is well driven. Watch out for overload lights on active speakers, particularly at high frequencies. If you have an SLM I recommend 85-90dB SPL with slow response and C weighting. Label each measurement and move on. Top |
'ETF and FuzzMeasure will not tell you simply what is wrong, how to treat your room, where to put what. They can, however, bestow great certainty when making comparative choices.' | HOW TO VIEW IT Don't panic! The curves almost always look awful. Frequency response graphs shows scary peaks and dips. Waterfall plots will often show one very low extremely long decay, plus a confusing array of peaks and dips up through the spectrum. Let's take a real world example, shown in Figure 2 at left. This room is from hell. It has mostly concrete surfaces, it is asymmetrical, and worst of all it has alcoves. It is a tuned indoor swimming pool. The green Before curve shows the room with elementary treatment; the red After curve is with much more considered treatment, of considerable quantity and quality. We did the lot; four corners, alcove corners, ceiling cloud, RFZ. Sadly, the After curve has a very similar shape to the Before. Disappointing. Let's look closer, with focus on the one big issue; the musically crucial 100 Hz zone. Here we find a 6 dB improvement. Now, consider if you were to EQ a full mix with such a broad 6 dB boost. This is a big and welcome change. A poll of 7 professional sound engineers was done in this room. All aspects averaged, the room scored 9 out of 10. Before it was a 6. Perhaps the curves don't do justice to the great sound and the great change. The frequency plot does deliver some clear and solid advice though: review the speaker positions. Be careful of bass decisions in the 100 Hz zone. Try listening at spots in the room where the graph is flattest. Use top quality headphones to judge kick drum and bass relationships. Top The waterfall plots told another story. On a cursory glance, the After again looked very similar to Before in shape, just generally shorter. Octave reverb time measurements varied a lot with position - some were zero. I am somewhat doubtful as to the accuracy of reverb time measurements in such a small dead room. I will point out, however, that once again, zooming in to an area of particular interest clearly illustrates a spectacular change. The Before waterfall showed a 1.3 second long boom at 37 Hz. After, it was reduced to 0.7 Seconds. Sonically, this changed a kick drum from a chest massage to a nice 'subby' thump. Note there is almost no sign of this huge anomaly in the averaged frequency response graph. CONCLUSIONS ETF and FuzzMeasure will not tell you simply what is wrong, how to treat your room, or where to put treatment. They can, however, bestow great certainty when making comparative choices. Acoustics can be a fascinating and useful study. I find knowledge of how sound behaves extremely helpful in recording. There is a wealth of knowledge all over the RealTraps site and elsewhere. There is simple clear advice as to where to put treatment and why. All the advice agrees on the basics; broadband or bass traps in the corners, a ceiling cloud, plus side-wall and ceiling reflection points. This is not voodoo and it doesn't change from room to room. Treat the room first, then use software and other tools to make informed choices - best speaker position, best seating positions, best speaker EQ settings, and so forth. Room treatment will yield spectacular results, no doubt. The use of measurements to decide on positional and other tweaks is the icing on the cake, not the dough. Top Sound Engineer 'DanDan' FitzGerald began by mixing at music gigs. This was followed by some international fame for his 'hi-fi' studio and location recordings. In the early 1990s his recording of No Frontiers by Mary Black took over from Ricky Lee Jones as the test CD in magazines and at trade shows. DD currently records and mixes Other Voices, a live music TV series. This year Other Voices was broadcast in HD with 5.1 by RaveHD globally. Recorded in a tiny church in Dingle at the western edge of Europe, the series recently featured Ryan Adams and Amy Winehouse. The entire series can be viewed online at Other Voices. Dan is now developing an acoustics and noise control consultancy SoundSound Acoustics. |
Fuzzmeasure
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