Phonic PAA3 Audio Analyzer

[Big Daddy]

Additional reading:
https://forum.blu-ray.com/audio-theo...orrection.html
https://forum.blu-ray.com/audio-theo...hnologies.html
https://forum.blu-ray.com/speakers/1...ubwoofers.html.
https://forum.blu-ray.com/pre-pro-am...h-fbq6200.html

I am certain that most people who have an interest in audio and home theater are well aware of the importance of equalization and room correction in addition to wall treatments and bass traps.

In a typical small home theater room, the sound waves interact heavily with the boundaries and other obstacles in the room. This interaction is more pronounced in the case of lower frequency bass waves. These waves have very long wavelengths that are several times larger than the dimendions of a typical home theater room. As a result of these interaction between the room boundaries and the lower frequency waves, standing waves are created. Additionally, there will be room gain in the lower frequencies below 100Hz.

These standing waves create room modes. The main result of these room modes is that the bass will become uneven in the room. At some locations, the bass will be too loud and at some locations, it will be very difficult to hear any bass. One solution is to use multiple subwoofers (two or four). Another solution is to use bass traps in the room. The third solution is equalization, particularly equalization in the lower frequencies.

In the vast majority of home theater rooms, equalization and speaker level setting is handled by auto calibration programs such as Audyssey. Additionally, some users may use manual bass equalization with equipment such as the Velodyne SMS-1 or sofware programs such as REW or TrueRTA and calibrated microphones. Because the most important problems in small home theater rooms are experienced in the lower frequencies, it is best to use equipment that can handle one-tenth to one-twenty fourth per octave equalization for frequencies below 200Hz.

Professional users have a different problem. Most of them have to deal with much larger rooms such as movie theaters, auditoriums, and indoor stadiums. For them, bass is not the main problem. Dialog intelligibility, reverberation, feedback, and other higher frequency problems become much more important. As a result, we see an abundant numbers of one-third per octave graphical equalizers in the pro market. Using these manual equalizers by ear alone is not sufficient. One option is to use an SPL meter and a lot of patience. Unfortunately, many SPL meters are not very reliable across all frequencies and doing the work manually is tedious and subject to error.

I recently upgraded my two-channel room with a tube pre-amp, a CD player with superb DAC, a better turntable/cartridge, and two super tower DIY speakers with 15" amplified subwoofers. Although the results were excellent, I realized that the only thing missing from my two-channel room was equalization. The room is rather large and open. Its dimensions are:

• Length: 30ft.
• Width: Open area with stairs. The distances between the left wall and the boundaries on the right are 18ft, 22ft, 25ft, 31ft, and 40ft.
• Height: Sloped from 13ft to 20ft and an area in the rear of has a height of 8ft.

It is not exactly the ideal room to deal with. Additionally, bass frequencies may not be the only problems in this room as it is a relatively large room. For this reason, I decided to search for a manual equalizer that can handle the entire audible frequency range. Additionally, I needed something that would have a reasonable cost as I had no intention to end up in a divorce court.

After some search, I ended up buying the Behringer UltraGraph FBQ6200. Initially, I tried to use one-third octave test tones and two SPL meters (a digital Radio Shack purchased over fifteen years ago and an American Recorder Technologies SPL meter purchased a couple of years ago) to equalize the room.

There are basically three types of problems when you do manual equalization:

1. Running test tones and measuring the response with an SPL meter is very tedious. The biggest problem is the unreliable SPL meters. I have two different SPL meters and that helped a little. Also, I use the Rives Audio test tones. It has two set of one-third octave test tones. The first set is raw and the second set is corrected for the inaccuracies of the Radio Shack SPL meter. The main difference is in the ultra low and ultra high frequencies.
2. When you fix the frequencies of each channel and then run both channels together, the frequencies interact and you have to do a lot of additional adjustment.
3. The frequencies are inter-dependent. When you raise the dB level of any frequency, it may affect other frequencies and you need to go back and adjust the other frequencies and run test tones again.

After spending several frustrating hours running test tones and taking measurements with my two flawed SPL meters, I was not satisfied with the results of either SPL meter and finally got fed up and decided to invest in something better. I began my search and did not give up until I found a little instrument that I thought would satisfy my needs. The regular price of this little gadget is as much as a medium-priced receiver, but I managed to find an open box unit at a discount.

PHONIC PAA3 HANDHELD AUDIO ANALYZER WITH USB INTERFACE

Website: http://www.phonic.com/en/paa3.html

Manual: https://phonic.boxcn.net/shared/fx8ydgar4a

Reviews:
http://mixonline.com/gear/reviews/au..._paa_portable/
http://www.workingdj.com/2009/06/28/...-audio-tester/

Price: The normal price is $499. Ocassionally, you may find it at dealers such as Amazon or Ebay for $400.

Where to Buy:
http://www.amazon.com/Phonic-Hand-He.../dp/B0009RK7YS
http://www.ebay.com/sch/i.html?_odkw...+PAA3&_sacat=0
http://www.bhphotovideo.com/c/produc...eld_Audio.html
http://www.musiciansfriend.com/acces...ource=3WWRWXMB
http://www.samedaymusic.com/product--PHOPAA3
http://www.allprosound.com/catalog/p...honic-PAA3.htm

Controls and Display

The PAA3 is a highly accurate handheld audio analyzer that gives sound engineers a rich array of sound analysis tools. Features include 31-band real time spectrum analysis, RT60, SPL and line meter, internal generator, EQ setting program, microphone calibration and speaker phase checking abilities. All functions and menus can be accessed through a central jog dial, leaving your other hand free to adjust audio settings. Easily upload information and settings to your computer via the built-in USB interface. The large LCD screen has a visible backlight to help you see in a dark performance environment. With a battery life of 7 hours, the PAA3 is a must-have multi-functional tool for all serious audio engineers.

The Phonic PAA3 Personal Audio Assistant, a highly accurate audio analyzer that sits comfortably in the palm of your hand, and features all the tools you need to set up any audio system.

With 31-band real-time spectrum analysis, Sound Pressure Level and dBu / dBV / line voltage measurement, EQ setting, phase checking, and reverb time analyzation, the PAA3 is the ideal companion for all sound engineers. This personal audio assistant is battery powered (4 AA size),
with a built in microphone, and XLR inputs and outputs, ensuring all audio analyzing situations are possible. With the PAA3, you will conquer the acoustics of all environments with precision and ease.

RTA (REAL TIME ANALYZER) - ACOUSTIC
This function analyzes the audio received through either the built-in mic or Line In connection, divided into 31-bands at 1/3 octave intervals, and displays the relevent information on a bar graph that shows the decibel level of each band of sound from 20 Hz to 20 kHz in four different response times (35 ms, 125 ms, 250 ms, and 1 sec) and in three weighting types (A weighting, C weighting and Flat).

SPL METER
This feature of the PAA3 gives users an accurate measurement of the overall “loudness” of their sound, measured in decibels (dB). This is a true RMS-measurement, using standard display time average, and standard A, C, and Flat weightings.

RT60 (REVERB TIME ANALYZING)
The RT60 function of the PAA3 is easy enough to understand: it is basically the time it takes for a signal to drop 60 dB. Getting the average of many different RT60 calculations from around a room allows users to get an idea as to how much absorption or reflection of audio the room provides. Depending on your needs, you may wish to have a high or low RT60 measurement. For example, for public speaking, an RT60 measurement of less than 1 second is preferable, as to have a clear, concise voice conveyed to the audience. With choirs or instrumental music, an RT60 measurement of greater than 1.5 seconds may be appropriate. It all depends on your needs.

RTA (REAL TIME ANALYZER) - ELECTRICAL SIGNAL
By simply connecting an XLR jack to the PAA3’s in jack, the RTA function can accurately measure your signal.

Level Meter: Measure the line voltage level in units of dBu, dBV, and AC voltage, using standard A, C, or flat weightings (under normal conditions, flat is preferable). Using the PAA3 to measure DC voltage may damage the PAA3 and will void the warranty.

MEMORY
The user can save up to 10 sets of measured data (1 to 10), as well as 6 averaged sets (A to F), into the memory of the PAA3, allowing them to be used later for further analysis or uploading to your computer.

EQ SETTING
The EQ setting of audio system will vary from one venue to another. The ultimate goal in setting your EQ is to create a completely flat response ans to eliminate every possible source of feedback.

Weighting: Any audio analyzer needs to be designed so that it hears sound properties in the same way as humans. Generally, the sensitivity of human hearing is restricted to the frequency range of 20 Hz to 20 kHz. The human ear, however, is most sensitive to sounds in the range of 500 Hz to 8 kHz. The ear becomes progressively less sensitive to sound out of this range. To account for this limitation of human hearing, many audio analyzers, including the PAA3, incorporate a filtering of acoustic signals according to frequency. This filtering (weighting type) is devised to correspond to the varying sensitivity of the human ear to sound over the audible frequency range. The PAA3 comes with both A-weighting and C-weighting standardized by the ANSI (American National Standards Institute). A-weighting is the most frequently used weighting type and is used for measuring lower sound levels, while C weighting is best suited for higher sound levels. The user can set the weighting for measurements in dBu, dBV or voltage.

PHASE CHECK
Measuring the phase of a signal allows you to figure out whether a speaker is correctly wired. A polarity signal is usually needed when checking the phase of a speaker or ensure that an output connection is correct.

GENERATOR
The PAA3 can send out pink noise, a polarity signal, and a 1 kHz tone, all of which is sent out via the Male XLR connector (on the bottom of the PAA3) to any external system, at a level of -10 dBu.

SIMULTANEOUS OPERATION WITH DESKTOP
There are many advantages to being able to connect the PAA3 with your desktop computer or notebook. It allows remote operation of the PAA3, for one, which is particularly useful when taking measurements in areas that require an absence of any individuals. It also allows users to save and print data stored in the PAA3’s memory. The PAA3 software, supported by Windows 98 and above, can be found on the included CD (which, incidently, also contains 26 testing signals). With this program, most functions are easily accessible through a menu identical to that of the PAA3 device itself.

[Big Daddy]

FedEx delivered the Phonic PAA3 in one day. It was shipped from Sacramento, CA to Southern California. That is about a six to seven hour drive. Kudos to Fedex.

After I spent an hour becoming familiar with the little instrument, I did not hesitate and started the equalization process. You have the choice of running pink noise from the included CD or you can connect the PAA3 to the pre-amplifier with an XLR to RCA cable and run the internal test tones generated by PAA3. I decided to use the CD as I play CDs most of the time in my two-channel room. My thinking is that any effect that the CD player, other equipment, and the cables may have on the sound will also affect the test tone CD.

This little gadget is amazing. After you run the pink noise for less than a minute, it generates the SPLs for all the thirty one (31) one-third octave frequencies from 20Hz to 20,000Hz. You can save the results in one of the ten different memory locations numbered from 1 to 10. You can put the microphone in as many as ten or less locations and take measurements. Afterwards, you can tell it to average the measurements saved in whatever memory units you want and it does that almost instantaneously. Additionally, it calculates the offsets by which you should increase or decrease the levels on the equalizer. All the averages can be saved in six different memory units labeled A, B, C, D, E, and F. It really makes the job of using an equalizer very easy.

Anyway, I first set the stereo system to flat without any equalizations and took measurements for each speaker independently and then both speakers combined. After I took three sets of measurements for several locations and averaged them, the Phonic analyzer gave me all the offsets I needed. I used those numbers and adjusted the Behringer equalizer and took additional measurements after equalization and did a few more adjustments until all the frequencies were within +/-3dB. You can see some of the results generated by the Phonic PAA3 analyzer in the following. You can find additional information in post #2 of the https://forum.blu-ray.com/pre-pro-am...h-fbq6200.html thread.

I have to say that this little beauty is the greatest invention since sliced bread.

[DangeRuss]

Great new thread.....BD

I'm looking forward to your report

[prerich]

Originally Posted by Big Daddy

The results will be posted here.

Allprosound.com ..... Big Daddy - you're messin' down in my neck of the woods now !!!!

[Big Daddy]

Originally Posted by prerich

Allprosound.com ..... Big Daddy - you're messin' down in my neck of the woods now !!!!

I have never dealt with Allprosound.com and know nothing about them. I did a quick search and listed a few places that sell the Phonic PAA3. Is there something about them that I should know?

[Fors*]

Very cool item you have there BD.....is it easy to use? It appears to be, but would someone need an additional EQ to properly calibrate the lower frequencies with this device?

[Big Daddy]

Originally Posted by Fors*

Very cool item you have there BD.....is it easy to use? It appears to be, but would someone need an additional EQ to properly calibrate the lower frequencies with this device?

It is a jack of all trades. It can work as a high quality SPL meter with a calibrated microphone. It does all the equalization calculations for up to ten positions. It can average the values of any number of positions. It can calculate revernerations time. It can even make pizza.

Once you play with it for an hour, it becomes very easy to use. You definitely need an equalizer as this instrument calculates the values and makes recommendations on much you should increase or decrease each frequency. I use it with the Behringer Equalizer. Check post #2 of that thread. I have posted all the preliminary results. I need to fix the graphs.

This little gadget is for general equalization across all the frequencies from 20Hz to 20,000Hz. It does the calculations for one-third octave frequencies and should be used with one-third octave graphical equalizers that are pretty common in the pro markets. Although you can use it to manually equalize a subwoofer, it is better to use a one-sixth octave graphical equalizer. Those equalizers are rare. To the best of my knowledge, Audio Control is one of the few companies that makes a multi-channel equalizer that allows one-sixth octave equalization only for the bass frequencies. Unfortunately, it is too expensive.

[Big Daddy]

Additional information was added to Post #2 of this thread.

[srrndhound]

Originally Posted by Big Daddy

This little gadget is for general equalization across all the frequencies from 20Hz to 20,000Hz. It does the calculations for one-third octave frequencies and should be used with one-third octave graphical equalizers that are pretty common in the pro markets. Although you can use it to manually equalize a subwoofer, it is better to use a one-sixth octave graphical equalizer. Those equalizers are rare.

Just as well. It's better to spend money on modern EQ technologies. Even 1/6th-octave EQ are not optimal, as the Q is often too low and the center frequency at the wrong value to hit the resonance dead on.

Here's some info on this matter from Dr. Toole's book, Sound Reproduction:

13.5.1 Practical Resolution Issues—How Some Reputations
Get Tarnished

For at least half a century, acoustical measurements have been made using fractional-octave bandwidth analyzers. The most common has been the 1/3-octave version, partly because it somewhat resembled auditory critical bands over much of the audible bandwidth. Critical bands are not the final answer in terms of sound quality or timbre (more in Chapter 19).

In measurements of loudspeakers in rooms, the curve smoothing offered by the wider bandwidth was attractive; the ugly and not very informative “grass” went away, making everyone feel better. Massive numbers of 1/3-octave “real-time” analyzers invaded the acoustics field. Multifilter “graphic” equalizers of 1/3-octave band also fl ooded the market, providing a tidy match between the measured data and the “draw-a-curve” style of equalization. At frequencies above the transition frequency, there is still a modicum of utility in this approach. However, at low frequencies in small rooms, measurements of this kind can be greatly misleading. The big problem is that the limited bandwidth of the measurement system cannot reveal the true nature of resonances—amplitude, center frequency, and Q—and the corresponding limited nature of the matching equalizers cannot address the resonances with a matching fi lter. Adding to the deficiency are those measurement systems that employ fixed-frequency filters, presenting their data as histograms, bar graphs, or staircase line drawings, as shown here. A swept filter is preferable.

[Big Daddy]

Originally Posted by srrndhound

Just as well. It's better to spend money on modern EQ technologies. Even 1/6th-octave EQ are not optimal, as the Q is often too low and the center frequency at the wrong value to hit the resonance dead on.

Here's some info on this matter from Dr. Toole's book, Sound Reproduction:

I completely agree with you. I was only talking in the context of graphical equalizers and what is available in the marketplace. Even with graphical equalizers, you need a resolution of at least 1/10 to 1/24th-octave to do a reasonable job with bass frequencies and those things do not exist. Even parametric equalizers are limited in what they can do with the lower frequencies.

Although a few external electronic equalizers are available to deal with the lower frequencies, there are not too many external equalizer options available in the home market to deal with the entire frequency range. I know of a couple that are available in the pro market, but even those are very expensive and have limited range. I may be wrong, but to the best of my knowledge, Audyssey and SVS stopped selling their external subwoofer equalizers.

I suppose, it is best for most people to use the built-in programs in their multi-channel receivers such as Audyssey in their home theaters to handle these problems. Unfortunately, there are not too many options available for people who use traditional two-channel systems.

[srrndhound]

Originally Posted by Big Daddy

Even parametric equalizers are limited in what they can do with the lower frequencies.

Although a few external electronic equalizers are available to deal with the lower frequencies, there are not too many external equalizer options available in the home market to deal with the entire frequency range. I know of a couple that are available in the pro market, but even those are very expensive and have limited range. I may be wrong, but to the best of my knowledge, Audyssey and SVS stopped selling their external subwoofer equalizers.

You mentioned the Behringer FBQ6200 graphic EQ, but the better choice is their parametric EQ: DEQ2496.