Griff `91: Design
 Griff ’91: Design Collin Doerr-­‐Newton Spring 13 Table of Contents Functional Description .................................................................................... 3 Design Goals ........................................................................................................ 4 Size ......................................................................................................................................................... 4 SPL Output ........................................................................................................................................... 4 Bandwidth ........................................................................................................................................... 5 Directivity ........................................................................................................................................... 5 Design Priorities ............................................................................................................................... 5 Visual Aesthetics ............................................................................................................................... 6 Technical Details ............................................................................................... 7 Driver Size and Spacing .................................................................................................................. 7 Baffle Step ........................................................................................................................................... 7 Low Frequency Alignment ............................................................................................................. 7 Diffraction Effects ............................................................................................................................. 8 Wall Construction and Bracing .................................................................................................... 8 Driver Selection .............................................................................................. 10 Tweeter Analysis and Selection ................................................................................................. 10 Woofer Analysis and Selection ................................................................................................... 14 Cross-­‐Over Design .......................................................................................... 24 Type ..................................................................................................................................................... 24 Driver Attenuation ......................................................................................................................... 24 Impedance Equalization ............................................................................................................... 25 Crossover Schematic Draft .......................................................................................................... 25 Testing and Tuning ........................................................................................ 27 Driver Performance ....................................................................................................................... 27 Enclosure Optimization ................................................................................................................ 28 Cross-­‐over Tuning .......................................................................................................................... 28 Final System Documentation ...................................................................... 31 Final Testing Results ..................................................................................................................... 31 Cross-­‐over Schematic .................................................................................................................... 42 As-­‐built Drafting ............................................................................................................................. 42 Appendix ........................................................................................................... 49 A) Tweeter Specification Sheets ................................................................................................ 49 B) Woofer Specification Sheets .................................................................................................. 57 Bibliography .................................................................................................... 63 2 Functional Description This loudspeaker system will be used primarily for my own personal music listening purposes. Specifically, these loudspeakers will be used for backward listening, meaning that they will be used to accurately reproduce an original signal.1 These speakers will need to be accommodating to a college student with not a lot of space, meaning they will be fairly mobile, and will be able to fit on top of a medium sized desk, probably near a wall. Finally, this system will be achieved with a budget of $700. 1 Moulton, David. Total Recording: The Complete Guide To Audio Production and Engineering. KIQ Productions, 2000, 313. 3 Design Goals Size As previously mentioned in the functional description (pg. 4), I intend to use these loudspeakers mounted on a medium sized desk. Therefore, the size of these speakers is going to need to be relatively small. My approximate listening axis is about 17 inches from the top of a medium sized desk. Considering this along with other elements of my functional description, I’ve determined that these loudspeakers will have dimensions of 16”x12”x20” (LxWxH). This would make the volume of them 2.22 ft3 (62.93 L). SPL in dBA SPL Output On the evening of January 25th, 2013, I measured my personal SPL preferences in Walker 210 on Michigan Tech’s campus. Listening to a variety of different genres and various levels, I determined that my personal preference for loud listening was about 79 dBA. Expanded results are shown in Figure 1. Taking these results into Personal Preference SPL consideration with the intended function of these 90 80 loudspeakers (music mixing), 70 Quiet I’ve determined that the 60 necessary maximum 50 Average continuous SPL output of Listening these loudspeakers will be 80 Loud dB, with a crest factor of 15-­‐
Genre 20 dB to be able to handle Figure 1 occasional peaks, meaning a maximum peak output of 100dB/1ft. Mixing louder than that can pose some significant negative effects to my hearing if done for long periods.2 2 Newell, Philip, and Keith Holland. Loudspeakers For Music Recording and Reproduction. Oxford: Elsevier Ltd., 2007, 251. 4 Frequency (Hz) Bandwidth Ideally, these loudspeakers would have low frequency extension all the way down to 20 Hz. Unfortunately, due to their smaller nature and to budget restrictions this is not really feasible. So in order to find an acceptable low frequency roll off point, I performed an experiment using Apple’s Logic Pro, Low Frequency Roll Off's applying a high pass filter to some of my favorite songs 100 80 from various genres in 60 order to measure my 40 Noticible Roll Off 20 personal preference for noticeable and acceptable Acceptable Roll Off low frequency roll off. The results are shown in Figure Genre 2. Taking these results into Figure 2 consideration with the purpose of the system (music mixing), I have determined that these speakers need to have low frequency extension down to 70 Hz, allowing for acceptable response to low frequencies, necessary for music mixing. Directivity I don’t move around the room much when I mix music, and I tend to do it alone as well, so wide dispersion of sound is not necessary for these speakers. With that being said, dispersion should not be extremely narrow, as I do like to move my head occasionally. Design Priorities As shown in Figure 3, my design priorities in order of importance are size, bandwidth, and maximum SPL. I am a college student with not a lot of space, so these speakers will need to be able to function SPL 20% Size 40% Bandwidth 40% Figure 3 5 in small spaces, like a residence hall room or a small bedroom. The primary function of these speakers calls for accurate frequency response, which is why bandwidth is of equal importance to size. Maximum SPL is of less importance to me. I prefer not to listen and mix at very high levels, so I am willing to sacrifice dB for a more suitable size and better frequency response. Visual Aesthetics Visually, I would like these speakers to be simple yet aesthetically pleasing. These speakers will be painted blue, possibly with a good accent of some kind. This coincides with the name of this system, Griff ’91, named after an organization that I am a part of that uses a Griffin as its emblem, and true blue and pure gold as its colors. 6 Technical Details Driver Size and Spacing Figure 4 shows my desired directivity for these speakers. Taking the anticipated crossover frequency of 2.5kHz into account, the distance between the centers of the tweeter and mid range driver would need to be about 3” in order to achieve this. I anticipate the mid range drivers Figure 4 to be between 6” and 7” in diameter and for the tweeter to be 1” in diameter. As you can probably imagine, the ideal of 3” between the two centers is not really possible. My goal, then will be to come as close as I can to 3” between the centers in order to achieve my desired directivity. Baffle Step Using the formula developed by John L. Murphy, I can easily find the frequency at which a 3 to 6 dB drop in low frequency response occurs as a result of the size of the baffle of these loudspeakers. The formula is: 𝑓! = 4560/𝑊! , Where 𝑊! is baffle width in inches-­‐3 Using my maximum baffle width of 12” (stated earlier in the “Size” section on page 4), I found the calculated frequency to be 380 Hz. Low Frequency Alignment In order to extend the low frequency response of my speakers, I will be constructing a vented box. While this will result in a worse off transient response, I am willing to trade that off for the extended bass response of a vented box. 3 Murphy, John L. True Audio. June 20, 2000. http://trueaudio.com/st_diff1.htm (accessed February 3, 2013) 7 Diffraction Effects Figure 5 from Newell and Holland shows the diffraction effects of a cabinet with a sharp edge.4 This edge diffraction can cause decreases in low frequency response due to the transition from baffled to unbaffled conditions at the edge of the cabinet. Edge diffraction can also cause uneven midrange response due to the “length differences from the Figure 5 diaphragm to different parts of the diffracting edges and on to the on-­‐axis observation point.” While diffraction can’t be completely avoided, I plan to combat these issues by using contoured edges to make the baffled to unbaffled transitions less abrupt.5 The frequency responses of certain cabinet shapes are shown in Figure 6.6 Note the difference in responses between the cabinets with contoured edges and those without. I plan to shape my speakers like what is shown on the top right, a rectangular shape with contoured edges. Figure 6 Wall Construction and Bracing *Note: Drafting can be found in the Appendix 4 Newell and Holland, Loudspeakers, 90.
5 Newell and Holland, Loudspeakers, 90. 6 Olson, Harry F. "Direct Radiator Loudspeaker Enclosures." Audio Engineering, November 1951: 38. 8 I will be constructing my cabinet walls using ¾” plywood for all of the outside walls. On the inside of the front and back walls, I will be using ¾” MDF in order to solidify them. For bracing, I will be using ¾” MDF in the shape of the figure 8, similar to what is shown in Figure 7.7 Figure 7 7 North Creek Music Systems. Cabinet Handbook. 2nd Edition. Old Forge, New York: North Creek Music Systems, 1992. 9 Driver Selection *Note: Manufacturer specification sheets for each driver below can be found in the Appendix Tweeter Analysis and Selection When it came to selecting tweeters, I wanted something that would offer a flat response above the crossover frequency, as well as offering the sensitivity necessary to reach my SPL output needs. Also, I needed to find something with a low enough resonant frequency to not cause any colorations. I ended up choosing the Vifa XT25TG30-­‐04. Below are some more specifications and descriptions for the 5 tweeters that I evaluated. Tweeter Name Sensitivity Max SPL X-­‐Max Fs Size Price (1ft) Tang Band 25-­‐1719S 90 dB 109 dB Ceramic 800 Hz 1” $31.58 Dome Vifa XT25TG30-­‐04 89 dB 110 dB Ring 530 Hz 1” $31.12 Radiator Fountek NeoCd2.0 97 dB 114 dB Ribbon Not 5” $199.00 specified ScanSpeak Classic 90 dB 111 dB Soft 650 Hz 1” $122.55 D2905/9300 Dome SEAS Prestige 90 dB 109 dB Soft 550 Hz 1” $50.70 27TDFC (H1189) Dome Tang Band 25-­‐1719S Table 1 shows some specifications for the Tang Band 25-­‐1719S tweeter. This tweeter reaches my SPL needs and also has a low enough resonant frequency, as I expect my crossover frequency to be somewhere around 2500 Hz. The frequency response of this tweeter is something that I liked as well. It appears to pretty flat throughout the spectrum that I plan to use it (appox. 2kHz-­‐20kHz). Finally, at a price of just over $31, it fits well into my budget. One troubling thing, however, is that off-­‐axis response is not shown on it’s response plot. 10 Tweeter Name Tang Band 25-­‐1719S Sensitivity 90 dB Max SPL (1ft) Style 109 dB Dome Fs 800 Hz Size Price 1” $31.58 Table 1 Vifa XT25TG30-­‐04 Table 2 shows specifications for the Vifa XT25TG30-­‐04. This tweeter is appealing to me because of its flat frequency response. It stays within about 2 dB of 90 dB through its entire intended use spectrum. Also, its sensitivity exceeds my needs, and its resonant frequency is low enough to not cause any real issues for me. The price is very good as well. Tweeter Name Vifa XT25TG30-­‐04 Sensitivity 89 dB Max SPL (1ft) 110 dB Style Ring Radiator Fs Size Price 530 Hz 1” $31.12 11 Fountek NeoCd2.0 Figure 3 shows specifications for the Fountek NeoCd2.0. A ribbon tweeter, I was impressed by steady frequency response throughout such a large spectrum. However, the price is a bit too steep for me to try out. Tweeter Name Sensitivity Fountek NeoCd2.0 97 dB Max SPL (1ft) Style 114 dB Ribbon Fs 300 Hz Size Price 5” $199.00 ScanSpeak Classic D2905/9300 12 Figure 4 shows specifications for the ScanSpeak Classic D2905/9300. The frequency response of this tweeter is pretty impressive, staying pretty flat until about 15kHz, where it begins to fall. However, like the Fountek ribbon tweeter, this tweeter is a little bit out of my price range. Tweeter Name Sensitivity Max SPL (1ft) Style ScanSpeak Classic D2905/9300 90 dB 111 dB Dome Fs 650 Hz Size Price 1” $122.55 SEAS Prestige 27TDFC (H1189) This tweeter is one that I actually like a lot. At 109 dB, its Max SPL fits well into my needs, and its frequency response is very flat until the higher frequencies. Also, its resonant frequency is low enough to not cause any problems for me. Lastly, the price is very appealing, at just over $50 apiece. Tweeter Name Sensitivity SEAS Prestige 27TDFC (H1189) 90 dB Max SPL (1ft) 109 dB Style Dome Fs Size Price 550 Hz 1” $50.70 13 Woofer Analysis and Selection When it came to selecting a woofer. I wanted to get as low as I possibly could, while also achieving a flat frequency response. Below are 5 woofers that evaluated closely before making my driver decision. The driver that I chose was the SB Acoustics SB17NRXC35. Woofer Name Sensitivity Max SPL X-­‐Max P(t) Fs Size (1ft) Tang Band W5-­‐1611SAF 90 dB 107 dB 3mm 56W 60 Hz 5” HiVi F8 87 dB 104 dB 5mm 60W 36 Hz 8” Peerless 830883 87.5 dB 104.5 dB 5.6mm 60W 52 Hz 6.5” ScanSpeak Classic 88 dB 109 dB 4mm 150W 37 Hz 6.5” P17WJ00 SB Acoustics SB17NRXC35-­‐8 89 dB 106 dB 5.5mm 60W 32 Hz 6” Price $50.32 $73.74 $79.14 $76.90 $48.00 Tang Band W5-­‐1611 SAF I like this Tang Band woofer because of its tight frequency response and its price. However, its low Xmax and its relatively high F3 trouble me. Also, in order to achieve ideal performance, a very small enclosure is necessary. I am designing something small, but not that small. 14 Woofer Name Sensitivity Max SPL X-­‐max P(t) (1ft) Tang Band W5-­‐1611SAF 90 dB 107 dB 3mm 56W Size Price 5” $50.32 Bass Boost Flat Extended Shelf 15 HiVi F8 The HiVi F8 is appealing to me for a few reasons. First off, I like the low F3. I also like that when this driver is given max power it is just barely hitting its max excursion. One other aspect that I like is its aesthetic quality. Its yellow color follows my color scheme. While it’s not necessarily a top priority, it is still a bonus. There are a couple of trouble spots in its frequency response such as dip at 850 Hz. Woofer Name HiVi F8 Sensitivity Max SPL X-­‐Max (1ft) 87 dB 104 dB 5mm P(t) Fs 60W 36 Hz 8” Size Price $73.74 Bass Boost 16 Flat Extended Shelf 17 Peerless 830883 There are some things that I really like about this Peerless woofer, like its tight response. However, in order to achieve its max potential, a small box size is necessary, even smaller than what I am hoping to make. Its sensitivity works for me, and its max SPL is suitable as well. The price is a little bit high but is in my range. Woofer Name Sensitivity Peerless 830883 87.5 dB Max SPL X-­‐Max P(t) Fs Size Price (1ft) 104.5 dB 5.6mm 60W 52 Hz 6.5” $79.14 Bass Boost Flat 18 Extended Shelf ScanSpeak Classic P17WJ00 Some good qualities of this ScanSpeak woofer are that it can get loud and it can get low. However, when it is given max power it far surpasses its max excursion limit. I’m not looking for distortion. Also, the price is a little bit on the high end of my range. Woofer Name Sensitivity Max SPL X-­‐Max P(t) Fs Size Price (1ft) ScanSpeak Classic P17WJ00 88 dB 109 dB 4mm 150W 37 Hz 6.5” $76.90 19 Bass Boost Flat Extended Shelf 20 SB Acoustics SB17NRXC35-­‐8 One thing that I really like about this SB Acoustics woofer is that it can achieve a pretty low F3 (about 45 Hz) while still being able to get loud, and the price is very attractive. I’m also very pleased with the low frequency response of this woofer. One other thing that I liked was that when this driver is given power up to its maximum handling, it still doesn’t really approach its maximum linear excursion limit. One area of concern is the sharp increase in frequency response around 3.5kHz. This is close to where my crossover frequency will be and there is some worry about whether or not this rise will cause any issues. Specs for this driver are shown below. Woofer Name Sensitivity Max SPL X-­‐Max P(t) Fs Size Price SB Acoustics SB17NRXC35-­‐8 89 dB 106 dB 5.5mm 60W 32 Hz 6” $48.00 21 Bass Boost Flat Extended Shelf 22 23 Cross-­‐Over Design Type I have decided to design a 4th-­‐order Linkwitz-­‐Riley crossover at 2000 Hz. The decision to design a Linkwitz-­‐Riley type crossover over, say, a Butterworth type crossover is the flat response resulting from summation. As you can see in Figure 7, a Butterworth type would result in a bump in frequency response at the crossover point due to summation, which is not something I want. Figure 78 Driver Attenuation Due to the difference in the sensitivities of my tweeter and woofer, I will need to incorporate driver attenuation into my crossover design. My woofer has a sensitivity of 88 dB while my tweeter has a sensitivity of 91 dB. Figure 8 shows a starting point for creating 3 dB of attenuation for my tweeter in the crossover, created at DIYaudioandvideo.com. 8 Wikipedia. Audio Crossover. Feb 25, 2013. http://en.wikipedia.org/wiki/Audio_crossover (accessed Mar 2, 2013). 24 Figure 89 Impedance Equalization In order to equalize the impedance of my woofer, I need to incorporate some components in my crossover to do so. Figure 9 shows a starting point for impedance equalization for the woofer I have chosen. Figure 910 Crossover Schematic Draft 9 Lalena, Michael. 2-­‐Way Crossover Designer / Calculator. lalena.com network. 2013. http://www.diyaudioandvideo.com/Calculator/XOver/ (accessed Mar 2, 2013). 10 Lalena, Michael. 2-­‐Way Crossover Designer / Calculator. 2013. 25 Figure 10 shows the draft that will serve as the starting point for my crossover. All of the previously stated factors are incorporated into this schematic. Figure 10 26 Testing and Tuning *Note: All initial testing and tuning was done about 6 feet from the ground, with a pad being used to minimize floor bounce. Driver Performance Below are the initial tests for each driver respectively, before tuning. Tweeter Woofer 27 Enclosure Optimization Below is the initial response of the loudspeaker system, before tuning. One thing that I wanted to fix with the enclosure was the jagged response between about 500Hz and 1.2kHz. I slowly began adding fiberglass to the enclosure until both the response was smoothed out, and I enjoyed the sound. Cross-­‐over Tuning Below is the initial response of the loudspeaker system, before tuning. 28 Some issues that I looked to fix with crossover tuning were: 1) the overall difference in level between the two drivers, and 2) the issues in the crossover region. I was able to easily fix the level of the tweeter by increasing the attenuation. This involved changing resistors in different combinations. I found that changing the resistor on the hot path changed the response of the tweeter from about 12kHz and up, while changing the resistor in the hot and ground path changed the response below 12kHz. Realizing this, I was able to fine-­‐tune the response of the tweeter. At the crossover region, I found that the tweeter was rolling off far too soon, and the woofer was not rolling of steep enough. By adjusting some of the values of the first inductor and capacitor of each circuit I was able to tune the crossover region to a more flat response. Below is the response of the finished crossover circuit: 29 One of the most interesting things throughout this process is how similar my final crossover design is to my initial design, despite how complicated and different I had (unnecessarily) attempted to make it. Throughout the process I had created various notch filters, none of which were necessary in the final design. 30 Final System Documentation Final Testing Results The final testing of the system was done about 12 feet from the ground. Upon this testing, I found that there was a slight dip in the response from 1.5kHz and up, as you can see the difference between the response shown below and the one shown above. Overall Loudspeaker Performance Frequency Response Integrated Frequency Response 31 Harmonic Distortion Percentage Minumum Phase Horizontal Off-­‐Axis Response 32 Vertical Off-­‐Axis Response Difference Plot 33 Step Response Integrated Step Response 34 Impulse Response Waterfall Plot 35 36 Woofer Performance Frequency Response 37 Harmonic Distortion Minimum Phase Step Response 38 Impulse Response Tweeter Performance Frequency Response 39 Harmonic Distortion Minimum Phase 40 Step Response Impulse Response 41 Cross-­‐over Schematic As-­‐built Drafting 42 43 44 45 46 47 48 Appendix A) Tweeter Specification Sheets Tang Band 25-­‐1719S TW
25-1719S
SERIES
25mm CERAMIC DOME
TWEETER
l CERAMIC DIAPHRAGM WITH FABRIC SURROUND
l BACK CHAMBER DESIGN, Fo OF 800Hz
l LOW 2
nd
AND 3 rd DISTORTION (LOW THD)
l EXCELLENT OFF-AXIS DISPERSION
DIAPHRAGM MTL
l FREQUENCY RESPONSE OF 800Hz ~ 30KHz
SURROUND MTL
l FERROFLUID COOLED
NOMINAL IMPEDANCE
4W
l MAGNETIC SHIELDED
DCR IMPEDANCE
3W
SENSITIVITY 1W/1M
FREQUENCY RESPONSE
FREE AIR RESONANCE
VOICE COIL DIAMETER
AIR GAP HEIGHT
RATED POWER INPUT
MAXIMUM POWER INPUT
FORCE FACTOR, BL
MAGNET WEIGHT ( oz)
MOVING MASS
Fabric
90 dB
800Hz -30K Hz
800 Hz
25.4 mm
2 mm
8W
80 W
N/A
Neodymium
N/A
FERROFLUID ENHANCED
Yes
SUSPENSION COMPLIANCE
N/A
EFFECTIVE PISTON AREA
Levc
Zo
VOICE: 886.2.26570282 FAX: 886.2.26580166
E-MAIL:[email protected]
Ceramic
N/A
0.002 mH
5.8 ohm
Xmax
N/A
Vas
N/A
Qts
N/A
Qms
N/A
Qes
N/A
49 Vifa XT25TG30-­‐04 XT/DX
1 Tweeter
Type Number: XT25TG30-04
Features:
The goal for this tweeter series was to create a transducer that
has a frequency response that is flat to above 20K, and where
the distortion is far lower than normal and more friendly to the
ear. The tweeters represent a unique approach to tweeter design
that has resulted in unrivaled performance, as well as in several
patents (Dual Ring Radiator diaphragm, wave-guide center plug).
Driver Highlights: Dual Ring Radiator diaphragm (Patent), Waveguide center plug (Patent), copper-clad aluwire
Specs:
Electrical Data
Nominal impedance
Minimum impedance
Maximum impedance
DC resistance
Voice coil inductance
T-S Parameters
Resonance Frequency
Mechanical Q factor
Electrical Q factor
Total Q factor
Force factor
Mechanical resistance
Moving mass
Suspension compliance
Effective cone diameter
Effective piston area
Equivalent volume
Sensitivity (2.83V/1m)
Zn
Zmin
Zo
Re
Le
4
-19
2.9
--
ohm
ohm
ohm
ohm
mH
fs
Qms
Qes
Qts
Bl
Rms
Mms
Cms
D
Sd
Vas
530
---2.5
0.38
0.3
--5.4
-91.1
Hz
Tm
Kg/s
g
mm/N
cm
2
cm
ltrs
dB
Power handling
Long-term Max Power (IEC 18.3)
Short Term Max power (IEC 18.2)
---
W
W
Voice Coil and Magnet Parameters
Voice coil diameter
Voice coil height
Voice coil layers
Height of the gap
Flux density of gap
Total useful flux
Diameter of magnet
Height of magnet
Weight of magnet
26
2.2
-2.5
------
mm
mm
mm
mWb
mWb
mm
mm
Kg
Notes:
IEC specs refer to IEC 60268-5 third edition.
All Tymphany products are RoHS compliant.
50 Frequency: XT25TG30-04
Mechanical Dimensions:XT25TG30-04
Tymphany™ and are trademarks of Tymphany Corporation. © 2009, Tymphany Corporation. All rights reserved.
012409
51 Fountek NeoCd2.0 NeoCD2.0 True Ribbon Tweeter
FEATURES
- strong Neodymium magnet
- 5 inch enforced sandwich diaphragm
- build-in impedance convertor
- low distortion, very fast transition
Parameter
Sensitivity
Power handling
Frequency range
Nominal impedance
DCR
Ribbon dimension
Effective ribbon area
Ribbon weight
Gap flux
Gap height
Recommend crossover frequency
Net. Weight
97dB/1m/2.83v
20W nominal, 50W max
1,200-40,000Hz
7 ohm
0.02 ohm
8mmX120mmX0.015mm
960 square millimeter
36 milligram
0.6 Telsa average
3 millimeter
2,500Hz with 3-order
1050 gram
www.fountek.net
email: [email protected]
tel: +86-573-8301 9220 fax: +86-573-8301 9221
52 110
SPL vs Freq
dBSPL
Deg
180
105
150
100
120
95
90
90
60
85
30
80
0
75
-30
70
-60
65
-90
60
-120
55
-150
50
1K Hz
2K
3K
4K
5K
6K
7K
8K
9K 10K
20K
30K
-180
40K
horizontal diffusion: on-axis, 15 degree , 30 degree, 45 degree
110
SPL vs Freq
dBSPL
Deg
180
105
150
100
120
95
90
90
60
85
30
80
0
75
-30
70
-60
65
-90
60
-120
55
-150
50
1K Hz
2K
3K
4K
5K
6K
7K
8K
9K 10K
20K
30K
-180
40K
vertical diffusion: on-axis, 5 degree , 10 degree
www.fountek.net
www.fountek.net
email: [email protected]
[email protected]
tek.net
tel: +86-573-8301 922
92200 fax: +86-573-8301 9221
53 www.fountek.net
www.fountek.net
email: [email protected]
[email protected]
tek.net
tel: +86-573-8301 922
92200 fax: +86-573-8301 9221
54 ScanSpeak Classic D2905/9300 TWEETER
D2905/930000
Advanced Parameters (Preliminary)
Electrical data:
Resistance [Re']
Mechanical Data
-Ω
Force Factor [Bl]
Free inductance [Leb]
- mH
Moving mass [Mms]
Bound inductance [Le]
- mH
Compliance [Cms]
Semi-inductance [Ke]
- SH
Mechanical resistance [Rms]
Shunt resistance [Rss]
-Ω
Admittance [Ams]
- Tm
-g
- mm/N
- kg/s
- mm/N
N.C. Madsensvej 1 — 6920 Videbæk — Denmark — Phone: +45 6040 5200 — www.scan-speak.dk
55 SEAS Prestige 27TDFC (H1189) 27TDFC
H1189
27TDFC is a High Definition precoated fabric dome tweeter with a wide, soft
polymer surround and a rear chamber.
Sonotex precoated fabric diaphragm with high consistency and excellent stability
against variations in air humidity
Sonomax surround for low resonance and excellent mechanical linearity.
Voice coil windings immersed in magnetic fluid increase short term power handling
capacity and reduce the compression at high power levels.
Stiff and stable rear chamber with optimal acoustic damping allows the tweeter to be
used with moderately low crossover frequencies.
The chassis is precision moulded from glass fibre reinforced plastic, and its front
design offers optimum radiation conditions.
100
50
95
90
40
85
SPL [dB]
30
75
70
20
65
60
Impedance [ohm]
80
10
55
50
100
0
1 000
10 000
Frequency [Hz]
The frequency responses above show measured free field sound pressure in 0, 30, and 60
degrees, mounted in a 0.6m by 0.8m baffle. Input 2.83 Vrms, microphone distance 0.5m,
normalized to SPL 1m. The impedance is measured without baffle using a 2V sine signal.
Nominal Impedance
6 Ohms
Voice Coil Resistance
Recommended Frequency Range
1500 - 25000 Hz
Voice Coil Inductance
0.05 mH
Short Term Power Handling *
220 W
Force Factor
3.5 N/A
Long Term Power Handling *
90 W
Free Air Resonance
550 Hz
Characteristic Sensitivity (2.83V, 1m) 90 dB
Moving Mass
0.37 g
Voice Coil Diameter
26 mm
Effective Piston Area
7.5 cm2
Voice Coil Height
1.5 mm
Magnetic Gap Flux Density
1.8 T
Air Gap Height
2.0 mm
Magnet Weight
0.25 kg
Linear Coil Travel (p-p)
0.5 mm
Total Weight
0.50 kg
Jul 2007-1
RoHS compliant product
4.8 Ohms
*IEC 268-5, via High Pass Butterworth Filter 2500Hz 12 dB/oct.
SEAS reserves the right to change technical data
T27-531
www.seas.no
56 B) Woofer Specification Sheets Tang Band W5-­‐1611 SAF F
SERIES
W5-1611SAF
5" PP FULL RANGE
l FULL RANGE DESIGN
l BLACK COLOR PP CONE WITH WIDE RANGE
TEMPERATURE,HIGH LOSS RECIPE OF RUBBER
SURROUND
l UNDERHUNG MOTOR DESIGN
l GF REINFORCED NYLON BASKET
DIAPHRAGM MTL
Black color pp
SURROUND MTL
Rubber
NOMINAL IMPEDANCE
8 W
DCR IMPEDANCE
6.3 W
SENSITIVITY 1W/1M
90 dB
FREQUENCY RESPONSE
FREE AIR RESONANCE
60 Hz
VOICE COIL DIAMETER
AIR GAP HEIGHT
10 mm
28 W
MAXIMUM POWER INPUT
56 W
FORCE FACTOR, BL
5.53 TM
( 18.6 oz)
MOVING MASS
FERROFLUID ENHANCED
SUSPENSION COMPLIANCE
No
1307 uMN -1
EFFECTIVE PISTON AREA
0.0094 M 2
0.023 mh
X-max
Vas
525 g
5.99 g
Levc
Zo
25.4 mm
RATED POWER INPUT
MAGNET WEIGHT
VOICE:886.2.26570282 FAX:886.2.26580166
E-MAIL :[email protected]
60 - 20K Hz
40 o hm
3 mm
11.69 Litr
Qts
0.44
Qms
2.80
Qes
0.52
57 HiVi F8 58 Peerless 830883 print close drawing application
Peerless Data Sheet
Type: HDS EXCLUSIVE
180 WR 33 102 NWP AL CU PH LS 8 OHM
Electrical data
Nominal impedance
Minimum imp./at freq.
Maximum impedance
Dc resistance
Voice coil inductance
Zn
Zmin
Zo
Re
Le
TS Parameters
Resonance Frequency
Mechanical Q factor
Electrical Q factor
Total Q factor
fs
Qms
Qes
Qts
52.3 (Hz)
2.79
0.50
0.43
Bl
Rms
Mms
Cms
D
Sd
Vas
8.2
2.09
17.7
0.52
13.1
134
13.0
87.5
Force factor
Mechanical resistance
Moving mass
Suspens. compliance
Effective cone diam.
Effective piston area
Equivalent volume
SPL 2.83V/1m at fmin
8
6.7/274
38.1
5.8
1.3
Power handling
100h RMS noise test (IEC)
Longterm Max System Power (IEC)
IEC268-5 noise signal is used for the powertest.
(ohm)
(ohm/Hz)
(ohm)
(ohm)
(mH)
(Tm)
(Kg/s)
(g)
(mm/N)
(cm)
(cm )
(ltrs)
(dB)
- (W)
- (W)
-
830883
Voice coil and magnet parameters
Voice coil diameter
Voice coil length
Voice coil layers
Height of the gap
Linear excursion +/Max mech. excursion +/Total useful flux
Diameter of magnet
Height of magnet
Weight of magnet
Factors
Ratio fs/Qts
Ratio BL/sqrt(Re)
33.0
17.0
2
6.0
5.5
1.1
102
20
0.68
(mm)
(mm)
(mm)
(mm)
(mm)
(mWb)
(mm)
(mm)
(kg)
122
3.4
Special remarks
-
Remarks on powertest
-
59 Measuring methods and conditions are stated in Peerless Standard for Acoustic Measurements (PSAM)
60 ScanSpeak Classic P17WJ00 vifa/scan-speak - datasheet
Page 1 of 1
P17WJ-00-08
Nominal impedance [ohm]
Voice coil resistance [ohm]
Nominal power [W]
Short term max power [W]
Long term max power [W]
Operating power [W]
Sensitivity [dB]
Frequency range [Hz]
Free air resonance [Hz]
Voice coil diameter [mm]
Voice coil height [mm]
Air gap height [mm]
Voice coil inductance [mH]
Eff. diaphragm Area [cm²]
Moving mass [g]
Magnet weight [g]/[oz]
Force factor [Bl]
VAS [l]
Qms
Qes
Qts
8
5.8
40
350
150
6.3
88
37-5000
37
32
14
6
0.55
136
14
415/14.6
6.5
34.7
1.55
0.45
0.35
OD:
170 mm
CD:
FT:
4.2 mm
ID:
146 mm
71.3 mm
MD:
91.8 mm
HD:
4xø[email protected]ø162
Frequency response: 2.83V / 1m
http://www.d-s-t.com/vifa/data/p17wj-00-08e.htm
12/20/2002
61 SB
SB Acoustics SB17NRXC35-­‐8 6” SB17NRXC35-8
85.9
75
Ø 100.0
Ø 144.9
Ø 171.0±0.4
Ø159.0±0.10
4-Ø8.50
4-Ø4.30
6.50
Specs :
FEATURES
· Vented cast aluminum chassis for
optimum strength and low compression
· Proprietary cone material with natural
fibers made in-house
· Soft low damping rubber surround
for transient response
· Non-conducting fiber glass voice coil
former for minimum damping
· Extended copper sleeve on pole piece
for low inductance and low distortion
· CCAW voice coil for reduced moving mass
· Long life silver lead wires
· Vented pole piece for reduced
compression
Nominal Impedance
8W
Free air resonance, Fs
32 Hz
DC resistance, Re
5.7 W
Sensitivity (2.83 V / 1 m)
89 dB
Voice coil inductance, Le
0.15 mH
Mechanical Q-factor, Qms
5.0
Effective piston area, Sd
Electrical Q-factor, Qes
0.36
Voice coil diameter
118 cm2
35.5 mm
Voice coil height
16 mm
Air gap height
5 mm
Linear coil travel (p-p)
11 mm
Equivalent volume, Vas
44.5 liters
Magnetic flux density
1.0 T
Compliance, Cms
2.25 mm/N
Magnet weight
0.54 kg
Mechanical loss, Rms
0.44 kg/s
Net weight
1.56 kg
Rated power handling*
60 W
Total Q-factor, Qts
0.34
Moving mass incl.air, Mms 11.0 g
Force factor, Bl
5.9 Tm
* IEC 268-5, T/S parameters measured on drive units that are broken in.
( IEC baffle, mic. distance 31.6 cm, SPL shown for 2.83 V / 1 m)
Response Curve :
------ (Blue) : on axis
------ (Green) : 30° off-axis
------ ( Red ) : 60° off-axis
62 Bibliography Lalena, Michael. 2-­‐Way Crossover Designer / Calculator. lalena.com network. 2013. http://www.diyaudioandvideo.com/Calculator/XOver/. Moulton, David. Total Recording: The Complete Guide To Audio Production and Engineering. KIQ Productions, 2000. Murphy, John L. True Audio. June 20, 2000. http://trueaudio.com/st_diff1.htm (accessed February 3, 2013). Newell, Philip, and Keith Holland. Loudspeakers For Music Recording and Reproduction. Oxford: Elsevier Ltd., 2007. North Creek Music Systems. Cabinet Handbook. 2nd Edition. Old Forge, New York: North Creek Music Systems, 1992. Olson, Harry F. "Direct Radiator Loudspeaker Enclosures." Audio Engineering, November 1951: 38. Toole, Floyd E. Sound Reproduction. Oxford: Elviser Ltd., 2008. Wikipedia. Audio Crossover. Feb 25, 2013. http://en.wikipedia.org/wiki/Audio_crossover (accessed Mar 2, 2013). 63 
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