ScanSpeak Revelator 22W/8857T-00 8″ Woofer, Aluminum Cone


Up for test is the ScanSpeak 22w Aluminum Cone, 8″ woofer.

I purchased two drivers and tested both in the small signal suite.  I only tested one driver for large signal results.

 

IMG_8765

IMG_8770 IMG_8772

 

Small Signal Testing:

Driver 1 Driver 2 Units
Electrical Parameters
Re 6.34 6.21 Ohm electrical voice coil resistance at DC
Le 0.264 0.251 mH frequency independent part of voice coil inductance
L2 0.546 0.46 mH para-inductance of voice coil
R2 1.56 1.57 Ohm electrical resistance due to eddy current losses
Cmes 442 450 µF electrical capacitance representing moving mass
Lces 53.61 54.35 mH electrical inductance representing driver compliance
Res 97.95 80.22 Ohm resistance due to mechanical losses
fs 32.7 32.2 Hz driver resonance frequency
——————
fm 23.2 28.3 Hz resonance frequency of driver with additional mass
Mechanical Parameters
(using add. mass)
Mms 34.936 30.36 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 31.249 26.673 g mechanical mass of voice coil and diaphragm without air load
Rms 0.806 0.842 kg/s mechanical resistance of  total-driver losses
Cms 0.679 0.805 mm/N mechanical compliance of driver suspension
Kms 1.47 1.24 N/mm mechanical stiffness of driver suspension
Bl 8.886 8.218 N/A force factor (Bl product)
Loss factors
Qtp 0.541 0.524 total Q-factor considering all losses
Qms 8.898 7.296 mechanical Q-factor of driver in free air considering Rms only
Qes 0.576 0.564 electrical Q-factor of driver in free air considering Re only
Qts 0.541 0.524 total Q-factor considering Re and Rms only
Other Parameters
Vas 46.5122 55.1206 l equivalent air volume of suspension
n0 0.271 0.313 % reference efficiency (2 pi-radiation using Re)
Lm 86.53 87.16 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom 87.54 88.26 dB nominal sensitivity (SPL at 1m for 1W @ Zn)

22W_8857T impedance

 

Large Signal Testing:

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=82% 9.1 mm Displacement limit due to force factor variation
X C @ C min=75% 10.4 mm Displacement limit due to compliance variation
X L @ Z max=10 % >11.8 mm Displacement limit due to inductance variation
X d @ d2=10% 38 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak 9.75 % Stiffness asymmetry Ak(Xpeak)
Xsym -0.09 mm Symmetry point of Bl(x) at maximal excursion

22W_8857T bl 22W_8857T bl symmetry 22W_8857T cms

22W_8857T kms

22W_8857T kms symmetry  22W_8857T lx 22W_8857T li

Kef LS50 Drive Unit


Up for test is the raw drive unit from Kef’s flagship LS50 monitor.

About a year ago I ran the gamut on some Kef drivers: the HTS3001SE concetric, Q100 5.25″ concentric, and the R-series concentric.  Knowing the lineage points to the LS50 drive unit as a mix of the Q-series concetric with it’s Z-flex surround and the R-series concetric with it’s ribbed cone for reducing breakup, I was curious to see the measured performance.  I finally was provided a drive unit to test, so here we go.

Photos:

Stock photo of the LS50 speakers captured from an image search via Google:

ls50lrg

My photos…

IMG_8503 IMG_8504 IMG_8505

 

 

 Woofer Testing:

Small Signal Measurements via Klippel:

Electrical Parameters
Re 3.01 Ohm electrical voice coil resistance at DC
Le 0.197 mH frequency independent part of voice coil inductance
L2 0.474 mH para-inductance of voice coil
R2 2.46 Ohm electrical resistance due to eddy current losses
Cmes 332 µF electrical capacitance representing moving mass
Lces 9.72 mH electrical inductance representing driver compliance
Res 27.62 Ohm resistance due to mechanical losses
fs 88.6 Hz driver resonance frequency
Mechanical Parameters
(using add. mass)
Mms 10.432 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 9.706 g mechanical mass of voice coil and diaphragm without air load
Rms 1.137 kg/s mechanical resistance of  total-driver losses
Cms 0.309 mm/N mechanical compliance of driver suspension
Kms 3.23 N/mm mechanical stiffness of driver suspension
Bl 5.604 N/A force factor (Bl product)
Loss factors
Qtp 0.507 total Q-factor considering all losses
Qms 5.107 mechanical Q-factor of driver in free air considering Rms only
Qes 0.557 electrical Q-factor of driver in free air considering Re only
Qts 0.502 total Q-factor considering Re and Rms only
Other Parameters
Vas 2.4278 l equivalent air volume of suspension
n0 0.291 % reference efficiency (2 pi-radiation using Re)
Lm 86.84 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom 88.07 dB nominal sensitivity (SPL at 1m for 1W @ Zn)
Madd 9.79 g additional mass
Sd 74.46 cm² diaphragm area

ls50 woofer impedance 1

Large Signal Testing with Klippel’s LSI Module:

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=82% 6.7 mm Displacement limit due to force factor variation
X C @ C min=75% 2.9 mm Displacement limit due to compliance variation
X L @ Z max=10 % >7.0 mm Displacement limit due to inductance variation
X d @ d2=10% 12.7 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak 7.59 % Stiffness asymmetry Ak(Xpeak)
Xsym 0.19 mm Symmetry point of Bl(x) at maximal excursion

Force factor Bl (X) Bl Symmetry Range Mechanical compliance Cms (X) Stiffness of suspension Kms (X) Kms Symmetry Range Electrical inductance L(X, I=0) Inductance over current L(X=0, I)

Frequency Response @ 2.83v/1m:

Note: Due to the rather tall surround and the fact I don’t have the trim ring used to flush mount the driver in a baffle, this driver was not flush mounted.  This will effect the high frequency response to some degree.

  • Black = 0 Deg
  • Orange = 30 Deg
  • Blue = 60 Deg

LS50 woofer 0 30 60

HD at 90dB/1m and 96dB/1m equivalent:

HD @ 90db

HD @ 96db

Tweeter Testing:

Small Signal Results:

Electrical Parameters
Re 3.14 Ohm electrical voice coil resistance at DC
Le 0.013 mH frequency independent part of voice coil inductance
L2 0.01 mH para-inductance of voice coil
R2 0.41 Ohm electrical resistance due to eddy current losses
Cmes 92 µF electrical capacitance representing moving mass
Lces 0.19 mH electrical inductance representing driver compliance
Res 1.02 Ohm resistance due to mechanical losses
fs 1205 Hz driver resonance frequency
Loss factors
Qtp 0.536 total Q-factor considering all losses
Qms 0.709 mechanical Q-factor of driver in free air considering Rms only
Qes 2.185 electrical Q-factor of driver in free air considering Re only
Qts 0.535 total Q-factor considering Re and Rms only

Frequency Response @ 2.83v/1m:

Note: Due to the rather tall surround and the fact I don’t have the trim ring used to flush mount the driver in a baffle, this driver was not flush mounted.  This will effect the high frequency response to some degree.

  • Black = 0 Deg
  • Orange = 30 Deg
  • Blue = 60 Deg

LS50 tweeter 0 30 60

 

HD at 90dB/1m and 96dB/1m equivalent:

HD @ 90db

HD @ 96db

SB Acoustics SB23NACS45-8 8″ Woofer


Up for test is SB Acoustics’ SB23NACS45-8, 8″ Woofer.

After looking at Revel’s new(ish) Performa3 Lineup, I realized that they are, at least in part, using SB acoustics drivers.  The Revel F208 uses (2) 8 inch woofers, which bear a striking resemblance to the SB’s under review here.Though, most certainly tweaked to fit their needs.  6moons.com did a review on the Revel F206 which contains pictures of the SB labeled drivers, pulled from their cabinets. In these pictures you can see the driver model number, containing the same naming scheme SB has for their drivers.  For example: 6moons’  picture of the tweeter in the f206 (here) carries the model number “SB26ADC-C000-4-RVL”.  You’ll notice SB’s site has a tweeter model #SB26ADC-C000-4.

Further, if you view the pictures of the raw woofer drivers, you’ll notice a lot of similarities such as the inverse-ribbed cone, and basket design.  While it seems apparent Revel used SB as an ally in the production of this speaker, odds are high Revel didn’t just use these SB drivers ‘off the shelf’.  One obvious difference is the black cone used in the Revel lineup rather than the aluminum colored cone presented here.  That said, the connection me curious about the ‘raw’ driver performance.  I went to SB’s site and located the 8″ driver.  I contacted Madisound to inquire about the product and was informed it wasn’t on their site just yet as they had recently taken shipment of them.  So, I placed an order for a set and got some testing done recently.

 

First, some photos:

IMG_8495 IMG_8501 IMG_8497 IMG_8498 IMG_8502

Testing the small signal parameters:

I tested both drivers back to back to compare their consistency.  Below are the values obtained for each.

Sample 1 Sample 2 Units Description
Re 5.47 5.48 Ohm electrical voice coil resistance at DC
Le 0.364 0.358 mH frequency independent part of voice coil inductance
L2 0.401 0.379 mH para-inductance of voice coil
R2 2.18 2.17 Ohm electrical resistance due to eddy current losses
Cmes 455 465 µF electrical capacitance representing moving mass
Lces 61.9 64.17 mH electrical inductance representing driver compliance
Res 50.6 48.9 Ohm resistance due to mechanical losses
fs 30 29.1 Hz driver resonance frequency
Mms 30.81 31.177 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 27.223 27.589 g mechanical mass of voice coil and diaphragm without air load
Rms 1.338 1.371 kg/s mechanical resistance of  total-driver losses
Cms 0.914 0.957 mm/N mechanical compliance of driver suspension
Kms 1.09 1.05 N/mm mechanical stiffness of driver suspension
Bl 8.23 8.189 N/A force factor (Bl product)
Qtp 0.423 0.42 total Q-factor considering all losses
Qms 4.338 4.162 mechanical Q-factor of driver in free air considering Rms only
Qes 0.469 0.466 electrical Q-factor of driver in free air considering Re only
Qts 0.423 0.419 total Q-factor considering Re and Rms only
Vas 60.3473 63.1788 l equivalent air volume of suspension
n0 0.334 0.322 % reference efficiency (2 pi-radiation using Re)
Lm 87.44 87.28 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom 89.09 88.93 dB nominal sensitivity (SPL at 1m for 1W @ Zn)
Madd 9.75 9.75 g additional mass
Sd 216 216 cm² diaphragm area

IMPEDANCE COMPARE

Overall, the comparison between the two units is pretty much on par.

 

 

Large Signal LSI Klippel Testing:

I didn’t have the time to test both samples so the following is all “Sample 1” driver.

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=82% 5.6 mm Displacement limit due to force factor variation
X C @ C min=75% 3.7 mm Displacement limit due to compliance variation
X L @ Z max=10 % >6.2 mm Displacement limit due to inductance variation
X d @ d2=10% 38 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak 25.39 % Stiffness asymmetry Ak(Xpeak)
Xsym -0.61 mm Symmetry point of Bl(x) at maximal excursion

SB Acoustics SB23NACS45-8 bl SB Acoustics SB23NACS45-8 bl sym SB Acoustics SB23NACS45-8 cms SB Acoustics SB23NACS45-8 kms SB Acoustics SB23NACS45-8 kms sym SB Acoustics SB23NACS45-8 lx SB Acoustics SB23NACS45-8 LI

Pioneer S-IW691In-Wall Speaker: Individual Drive Unit Testing


Pioneer S-IW691In-Wall Speaker: Individual Drive Unit Testing

A friend of mine ordered the Pioneer S-IW691 Elite® EX Series speakers for his home theater setup and sent one to me because he was curious just how well the individual drivers perform; namely the concentric mid/tweeter.  The same drivers are also used in Pioneer’s in-wall center channel.

The following is taken from Pioneer’s product information page:

Designed around our award winning EX floor-standing platform, the new Elite® EX Series not only redefines the entire architectural category, but also now offers an even more comprehensive solution for the most refined of audiophile tastes.

With an experience that blends seamlessly within any environment, the EX Series offers exceptional sound with all but complete invisibility.

Built with only the finest of hand picked materials, our patented Coherent Source Transducer (CST) driver technology offers every home cinema connoisseur the most enveloping and accurate “sweet spot” available today. To fully appreciate our Elite EX Series speakers, they simply must be experienced to be believed.

The S-IW691 is designed for custom home cinema and the demands of 2 channel critical listening applications. It features a 6 1/2” woven aramid/carbon composite bass driver, a 5 1/2” magnesium midrange and a 1 3/16” ceramic graphite tweeter built into a laminated MDF baffle. Add customizable features like Treble Contour Control and exceptional sound is always at your fingertips.

 

I always am interested in seeing how raw drivers in ‘kits’ like this perform, so let’s get to it…

 

Photos

Entire Unit

IMG_8380

IMG_8401 IMG_8402

Concentric Mid/Tweeter

IMG_8389

IMG_8381

IMG_8386

IMG_8387

Woofer

IMG_8394 IMG_8395 IMG_8396 IMG_8397

Test Results: Tweeter

TweeterSmall Signal Parameters:

Electrical Parameters
Re 4.46 Ohm electrical voice coil resistance at DC
Le 0.03 mH frequency independent part of voice coil inductance
L2 0.022 mH para-inductance of voice coil
R2 0.6 Ohm electrical resistance due to eddy current losses
Cmes 74 µF electrical capacitance representing moving mass
Lces 0.24 mH electrical inductance representing driver compliance
Res 21.99 Ohm resistance due to mechanical losses
fs 1186.9 Hz driver resonance frequency
Loss factors
Qtp 2.067 total Q-factor considering all losses
Qms 12.174 mechanical Q-factor of driver in free air considering Rms only
Qes 2.467 electrical Q-factor of driver in free air considering Re only
Qts 2.051 total Q-factor considering Re and Rms only

tweeter imp

Tweeter Frequency Response:

2.83v @ 1m, 0, 30, and 60 degrees

Note: The strong dip in response shown in the on-axis (black) is likely due to not flush mounting the drive unit (unfortunately, I don’t have the tools on hand to create such a flush mount).

  • Black = 0 Degrees (on-axis)
  • Orange = 30 Degrees
  • Red = 60 Degrees

tweeter 0 30 60

Tweeter Distortion:

Harmonic Distortion at 90dB and 96dB equivalent output:

  • Blue = THD
  • Red = 2nd Order
  • Pink = 3rd Order
  • Green = 4th Order
  • Teal = 5th Order

tweeter HD @ 90

tweeter HD @ 96

Intermodulated distortion and 90dB and 96dB equivalent output:

tweeter IMD @ 90 tweeter IMD @ 96

 

 

 

Test Results: Midrange

Midrange Small Signal Parameters:

Electrical Parameters
Re 4.54 Ohm electrical voice coil resistance at DC
Le 0.227 mH frequency independent part of voice coil inductance
L2 0.326 mH para-inductance of voice coil
R2 4.48 Ohm electrical resistance due to eddy current losses
Cmes 205 µF electrical capacitance representing moving mass
Lces 8.75 mH electrical inductance representing driver compliance
Res 20.1 Ohm resistance due to mechanical losses
fs 119 Hz driver resonance frequency
——————
fm 85.1 Hz resonance frequency of driver with additional mass
Mechanical Parameters
(using add. mass)
Mms 9.213 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 8.413 g mechanical mass of voice coil and diaphragm without air load
Rms 2.241 kg/s mechanical resistance of  total-driver losses
Cms 0.194 mm/N mechanical compliance of driver suspension
Kms 5.15 N/mm mechanical stiffness of driver suspension
Bl 6.712 N/A force factor (Bl product)
Loss factors
Qtp 0.567 total Q-factor considering all losses
Qms 3.073 mechanical Q-factor of driver in free air considering Rms only
Qes 0.693 electrical Q-factor of driver in free air considering Re only
Qts 0.566 total Q-factor considering Re and Rms only
Other Parameters
Vas 1.735 l equivalent air volume of suspension
n0 0.405 % reference efficiency (2 pi-radiation using Re)
Lm 88.28 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom 89.49 dB nominal sensitivity (SPL at 1m for 1W @ Zn)
Sd 79.46 cm² diaphragm area

mid impedance

Midrange Large Signal Parameters:

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=82% >2.0 mm Displacement limit due to force factor variation
X C @ C min=75% 1.4 mm Displacement limit due to compliance variation
X L @ Z max=10 % >2.0 mm Displacement limit due to inductance variation
X d @ d2=10% 9.6 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak -87.89 % Stiffness asymmetry Ak(Xpeak)
Xsym -0.01 mm Symmetry point of Bl(x) at maximal excursion

mid bl mid bl symmetry mid cms mid kms mid kms symmetry mid lx mid li

Midrange Frequency Response:

2.83v @ 1m, 0, 30, and 60 degrees

  • Black = 0 Degrees (on-axis)
  • Red = 30 Degrees
  • Blue = 60 Degrees

mid 0 30 60

 

Midrange Distortion:

Harmonic Distortion at 90dB and 96dB equivalent output:

  • Blue = THD
  • Red = 2nd Order
  • Pink = 3rd Order
  • Green = 4th Order
  • Teal = 5th Order

mid HD @ 90 mid HD @ 96

Intermodulated distortion and 90dB and 96dB equivalent output:

mid IMD @ 90 mid IMD @ 96

 

 

Test Results: Woofer

Woofer Small Signal Parameters:

Electrical Parameters
Re 4.79 Ohm electrical voice coil resistance at DC
Le 0.505 mH frequency independent part of voice coil inductance
L2 0.62 mH para-inductance of voice coil
R2 3.01 Ohm electrical resistance due to eddy current losses
Cmes 541 µF electrical capacitance representing moving mass
Lces 14.5 mH electrical inductance representing driver compliance
Res 24.9 Ohm resistance due to mechanical losses
fs 56.8 Hz driver resonance frequency
——————
fm 42.9 Hz resonance frequency of driver with additional mass
Mechanical Parameters
(using add. mass)
Mms 20.235 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 18.605 g mechanical mass of voice coil and diaphragm without air load
Rms 1.501 kg/s mechanical resistance of  total-driver losses
Cms 0.388 mm/N mechanical compliance of driver suspension
Kms 2.58 N/mm mechanical stiffness of driver suspension
Bl 6.114 N/A force factor (Bl product)
Loss factors
Qtp 0.778 total Q-factor considering all losses
Qms 4.813 mechanical Q-factor of driver in free air considering Rms only
Qes 0.925 electrical Q-factor of driver in free air considering Re only
Qts 0.776 total Q-factor considering Re and Rms only
Other Parameters
Vas 8.9472 l equivalent air volume of suspension
n0 0.171 % reference efficiency (2 pi-radiation using Re)
Lm 84.52 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom 85.5 dB nominal sensitivity (SPL at 1m for 1W @ Zn)
Sd 127.68 cm² diaphragm area

woofer impedance

Woofer Large Signal Testing:

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=82% >3.2 mm Displacement limit due to force factor variation
X C @ C min=75% 1.7 mm Displacement limit due to compliance variation
X L @ Z max=10 % >3.2 mm Displacement limit due to inductance variation
X d @ d2=10% 19.5 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak 64.93 % Stiffness asymmetry Ak(Xpeak)
Xsym 1.82 mm Symmetry point of Bl(x) at maximal excursion

woofer bl woofer bl symmetry woofer cms woofer kms woofer kms symmetry woofer lx woofer li

 

Woofer Frequency Response:

2.83v @ 1m, 0, 30, and 60 degrees

  • Black = 0 Degrees (on-axis)
  • Red = 30 Degrees
  • Blue = 60 Degrees

woofer 0 30 60

Woofer Distortion:

Harmonic Distortion at 90dB and 96dB equivalent output:

  • Blue = THD
  • Red = 2nd Order
  • Pink = 3rd Order
  • Green = 4th Order
  • Teal = 5th Order

woofer hd @ 90Db woofer hd @ 96Db

Intermodulated Distortion at 90dB and 96dB equivalent output:

woofer imd @ 90Dbwoofer imd @ 96Db

PHD FB 4.1 Midbass

PHD FB 4.1 Midbass Testing

Note:  Though these speakers are called ‘midbass’, I think their size and parameters lends them much more to a midrange use.

A set of these PHD speakers was loaned to me last year to test and I’m finally getting around to doing so.  While PHD is a 20-year old company, their presence hasn’t been really known (at least in my past 5-6 years in the car audio hobby) until the past couple years.  Given that, there’s very little actual testing on any of the PHD products that I’ve seen, and I hope to help change that.

Product info can be found at PHD’s website here.

IMG_8373IMG_8370

 

Small Signal Parameters:

Electrical Parameters
Re 3.32 Ohm electrical voice coil resistance at DC
Le 0.181 mH frequency independent part of voice coil inductance
L2 0.257 mH para-inductance of voice coil
R2 3.79 Ohm electrical resistance due to eddy current losses
Cmes 319 µF electrical capacitance representing moving mass
Lces 6.21 mH electrical inductance representing driver compliance
Res 28.71 Ohm resistance due to mechanical losses
fs 113 Hz driver resonance frequency
——————
fm 72.9 Hz resonance frequency of driver with additional mass
Mechanical Parameters
(using add. mass)
Mms 5.335 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 4.933 g mechanical mass of voice coil and diaphragm without air load
Rms 0.582 kg/s mechanical resistance of  total-driver losses
Cms 0.371 mm/N mechanical compliance of driver suspension
Kms 2.69 N/mm mechanical stiffness of driver suspension
Bl 4.088 N/A force factor (Bl product)
Loss factors
Qtp 0.677 total Q-factor considering all losses
Qms 6.51 mechanical Q-factor of driver in free air considering Rms only
Qes 0.753 electrical Q-factor of driver in free air considering Re only
Qts 0.675 total Q-factor considering Re and Rms only
Other Parameters
Vas 1.3283 l equivalent air volume of suspension
n0 0.245 % reference efficiency (2 pi-radiation using Re)
Lm 86.09 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom 86.9 dB nominal sensitivity (SPL at 1m for 1W @ Zn)
Sd 50.27 cm² diaphragm area

fb 4.1 kms impedance

Large Signal Parameters:

 

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=82% 1.4 mm Displacement limit due to force factor variation
X C @ C min=75% 2.6 mm Displacement limit due to compliance variation
X L @ Z max=10 % 1.9 mm Displacement limit due to inductance variation
X d @ d2=10% 9.4 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak 6.41 % Stiffness asymmetry Ak(Xpeak)
Xsym 0.91 mm Symmetry point of Bl(x) at maximal excursion

fb 4.1 bl fb 4.1 bl symmetry fb 4.1 cms fb 4.1 kms symmetry fb 4.1 kms fb 4.1 l(x) fb 4.1 lx(i)

 

 

Frequency Response:

The below is FR measured at 2.83v/1m, 0, 15, 30, 45, and 60 degrees with the accompanying polar.  You can see I stitched NF and FF at approximately 400hz, as this is where they lined up best for all axes.  These are smoothed to 1/12 octave.

  • Black= 0 Degrees (on-axis)
  • Red = 30 Degrees
  • Green = 60 Degrees

FR @ 0 30 60 2.83v

Non-Linear Distortion:

Harmonic Distortion, measured at approximately 5 inches from the cone, SPL emulating 90dB @ 1m and 96dB @ 1m.

  • Blue = THD
  • Red = 2nd Order
  • Pink = 3rd Order
  • Green = 4th Order
  • Teal = 5th Order

90dB @ 1m equivalent:HD 90db

96dB @ 1m equivalent:

HD 96db

 

IMD at 90dB/1m.  F1=110hz, F2=880hz (-6dB from F1).

IMD 90db 110_880

IMD at 96dB/1m.  F1=110hz, F2=880hz (-6dB from F1).

IMD 96db 110_880

Aura Sound NS6-255-8A


Aura Sound NS6-255-8A 6.5″ Midwoofer

IMG_8375 IMG_8379 IMG_8377

Small Signal Parameters:

Electrical Parameters
Re 5.69 Ohm electrical voice coil resistance at DC
Le 0.458 mH frequency independent part of voice coil inductance
L2 0.845 mH para-inductance of voice coil
R2 4.4 Ohm electrical resistance due to eddy current losses
Cmes 319 µF electrical capacitance representing moving mass
Lces 18.56 mH electrical inductance representing driver compliance
Res 83.75 Ohm resistance due to mechanical losses
fs 65.4 Hz driver resonance frequency
——————
fm 41.9 Hz resonance frequency of driver with additional mass
Mechanical Parameters
(using add. mass)
Mms 8.984 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 7.477 g mechanical mass of voice coil and diaphragm without air load
Rms 0.336 kg/s mechanical resistance of  total-driver losses
Cms 0.659 mm/N mechanical compliance of driver suspension
Kms 1.52 N/mm mechanical stiffness of driver suspension
Bl 5.307 N/A force factor (Bl product)
Loss factors
Qtp 0.702 total Q-factor considering all losses
Qms 10.98 mechanical Q-factor of driver in free air considering Rms only
Qes 0.746 electrical Q-factor of driver in free air considering Re only
Qts 0.698 total Q-factor considering Re and Rms only
Other Parameters
Vas 13.6902 l equivalent air volume of suspension
n0 0.494 % reference efficiency (2 pi-radiation using Re)
Lm 89.13 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom 89.37 dB nominal sensitivity (SPL at 1m for 1W @ Zn)
Sd 121.15 cm² diaphragm area

 

NS6 Impedance Klippel

 

Large Signal Parameters:

 

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=82% 2.5 mm Displacement limit due to force factor variation
X C @ C min=75% >7.3 mm Displacement limit due to compliance variation
X L @ Z max=10 % 5.2 mm Displacement limit due to inductance variation
X d @ d2=10% 18.3 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak 5.03 % Stiffness asymmetry Ak(Xpeak)
Xsym 0.63 mm Symmetry point of Bl(x) at maximal excursion

 

NS6 BL NS6 BL SYMMETRY NS6 KMS NS6 KMS SYMMETRY NS6 L(X) NS6 LX(I)

 

 

Frequency Response:

The below is FR measured at 2.83v/1m, 0, 15, 30, 45, and 60 degrees with the accompanying polar.  You can see I stitched NF and FF at approximately 400hz, as this is where they lined up best for all axes.  These are smoothed to 1/12 octave.

  • 0 Degrees (on-axis) = Green
  • Black = 15 Degrees
  • Dark Red = 30 Degrees
  • Red = 45 Degrees
  • Orange = 60 Degrees

NS6 FR

NS6 Polar

Non-Linear Distortion:

Harmonic Distortion, measured at approximately 5 inches from the cone, SPL emulating 90dB @ 1m.

  • Blue = THD
  • Red = 2nd Order
  • Pink = 3rd Order
  • Green = 4th Order
  • Teal = 5th Order

NS6 HD at 90db_1m

HD with a single tone in the spectrum view (I did this to verify the high odd order distortion seen above): NS6 HD at 1khz

IMD at 90dB/1m.  F1=55hz, F2=440hz (-6dB from F1).

NS6 IMD (1)

IMD at 96dB/1m.  F1=55hz, F2=440hz (-6dB from F1).

NS6 IMD (2)

GTG Sampler Disc Track List

Track Title Artist Album Length
1 End Of The Road (Live) Babyface MTV Unplugged NYC 1997 2:02
2 We Didn’t Start the Fire Billy Joel Storm Front 1:26
3 Turtle Shoes Bobby McFerrin Spontaneous Inventions 0:53
4 Don’t Worry Be Happy Bobby McFerrin The Story of Jazz 1:25
5 Peace of Mind Boston Boston (Original U.S.) 1:05
6 Drive The Cars The 80’s Greatest 1:07
7 Got A Hold On Me Christine McVie Christine McVie 1:04
8 Mr. Jones Counting Crows August and Everything After [MFSL UDCD 664] 1:40
9 Ants Marching Dave Matthews Band Under The Table And Dreaming 1:18
10 Rock Of Ages Def Leppard Pyromania (MFSL Ultradisc II Gold CD 520 0689) 1:09
11 Enjoy The Silence Depeche Mode Best Of Depeche Mode, Vol. 1 1:04
12 Money For Nothing Dire Straits Brothers In Arms 1:36
13 The Boys Of Summer Don Henley Building The Perfect Beast (MFSL) 1:17
14 Let’s Groove Tonight Earth, Wind, & Fire Greatest Hits 1:02
15 In The Ghetto Elvis Presley The Complete Elvis Presley Masters (Disc 18) 1:14
16 The Chain Fleetwood Mac Rumours 1:22
17 Sweet Child O’ Mine Guns N Roses Appetite For Destruction MFSL 0:46
18 You Make My Dreams Hall & Oates Voices (MFSL Gold Japan UDCD 530) 0:58
19 Never Heart Heart (MFSL) 1:24
20 No One Is To Blame Howard Jones The Platinum Collection 1:26
21 Aqueous Transmission Incubus Morning View 1:48
22 Breaking Silence Janis Ian Breaking Silence (Analogue Productions Limited Edition) 1:13
23 Life’s Been Good Joe Walsh But Seriously, Folks… 1:55
24 Rocky Mountain Way Joe Walsh The Smoker You Drink, The Player You Get 1:31
25 Word Up! Korn Greatest Hits Vol. 1 1:06
26 A Place For My Head Linkin Park Hybrid Theory 1:05
27 Grandma’s Hands Livingston Taylor Chesky Records – The Ultimate Demonstration Disc 0:48
28 Live To Tell Madonna True Blue 1:47
29 He Mele No Lilo Mark Keali’i Ho’omalu and Kamehameha Schools Children’s Chorus Lilo And Stitch 1:24
30 Early Bird Mark Knopfler Get Lucky 1:24
31 Remember The Time Michael Jackson Dangerous 1:12
32 Black Or White Michael Jackson HIStory: Past, Present And Future, Book 1 [Disc 1] 1:05
33 Kickstart My Heart Motely Crue Greatest Hits 0:59
34 Feel Like Going Home Muddy Waters Folk Singer 1:30
35 Wonder Natalie Merchant Tigerlilly (MFSL) 1:15
36 Perfect Drug Nine Inch Nails Lost Highway Soundtrack 1:05
37 Don’t Know Why Norah Jones Come Away with Me 1:11
38 When Can I See You Again? Owl City Wreck-It Ralph Soundtrack 1:07
39 You Can Call Me Al Paul Simon Graceland 1:00
40 Even Flow Pearl Jam Ten 1:30
41 Jeremy Pearl Jam Ten 1:18
42 Set Me On Fire Pendulum Immersion 1:14
43 This Is the Picture (Excellent Birds) Peter Gabriel So 1:21
44 In The Air Tonight Phil Collins Face Value 1:25
45 Wrapped Around Your Finger The Police Synchronicity 1:10
46 Jerry Was a Race Car Driver Primus They Can’t All Be Zingers 0:30
47 Know Your Enemy Rage Against The Machine Rage Against The Machine 1:37
48 Spanish Harlem Rebecca Pidgeon Chesky Records – The Ultimate Demonstration Disc 0:38
49 The Race is On Sawyer Brown Greatest Hits 0:53
50 Drum Improvisation Sheffield Labs Sheffield Lab Drum and Track Disc 1:21
51 Superstition Stevie Wonder Greatest Hits 1:07
52 Everybody Wants to Rule the World Tears For Fears Songs from the Big Chair [MFSL Ultradisc] 1:01
53 Africa Toto Legend: The Best Of 1:41
54 Behind The Wall Tracy Chapman Greatest Hits 0:20
55 Owner Of A Lonely Heart Yes Greatest Hits 1:11
56 Sharp Dressed Man ZZ Top Greatest Hits 1:18
57 Warning !!!! Reduce Volume Setup Tracks Iasca 0:19
58 25hz Setup Tracks Pink Noise Tracks 0:14
59 31hz Setup Tracks Pink Noise Tracks 0:14
60 40hz Setup Tracks Pink Noise Tracks 0:15
61 50hz Setup Tracks Pink Noise Tracks 0:12
62 63hz Setup Tracks Pink Noise Tracks 0:14
63 80hz Setup Tracks Pink Noise Tracks 0:13
64 100hz Setup Tracks Pink Noise Tracks 0:14
65 125hz Setup Tracks Pink Noise Tracks 0:14
66 160hz Setup Tracks Pink Noise Tracks 0:13
67 200hz Setup Tracks Pink Noise Tracks 0:14
68 250hz Setup Tracks Pink Noise Tracks 0:14
69 315hz Setup Tracks Pink Noise Tracks 0:14
70 400hz Setup Tracks Pink Noise Tracks 0:14
71 500hz Setup Tracks Pink Noise Tracks 0:13
72 630hz Setup Tracks Pink Noise Tracks 0:14
73 800hz Setup Tracks Pink Noise Tracks 0:14
74 1000hz Setup Tracks Pink Noise Tracks 0:14
75 1250hz Setup Tracks Pink Noise Tracks 0:14
76 1600hz Setup Tracks Pink Noise Tracks 0:14
77 2000hz Setup Tracks Pink Noise Tracks 0:13
78 2500hz Setup Tracks Pink Noise Tracks 0:13
79 3200hz Setup Tracks Pink Noise Tracks 0:14
80 4000hz Setup Tracks Pink Noise Tracks 0:13
81 5000hz Setup Tracks Pink Noise Tracks 0:14
82 6300hz Setup Tracks Pink Noise Tracks 0:14
83 8000hz Setup Tracks Pink Noise Tracks 0:13
84 10000hz Setup Tracks Pink Noise Tracks 0:13
85 12500hz Setup Tracks Pink Noise Tracks 0:14
86 16000hz Setup Tracks Pink Noise Tracks 0:13
87 20000hz Setup Tracks Pink Noise Tracks 0:11
88 center Setup Tracks Setup Disc 0:31
89 left Setup Tracks Setup Disc 0:34
90 left of center Setup Tracks Setup Disc 0:32
91 right Setup Tracks Setup Disc 0:38
92 right of center Setup Tracks Setup Disc 0:35
93 Correlated Pink Noise Setup Tracks Test CD #102 0:30

Pictures from the 2013 Car Audio Championships

The major car audio organizations recently capped off the year with a joint Finals at the VBCC in Huntsville, AL where both sound quality and sound pressure were represented with a combined 250+ (guesstimate) competitors.  If I had to guess, I’d say there was somewhere around 100-120 SQ competitors alone.  An awesome turnout.

Here are some random pictures from the event (with a few at the beginning thrown in from a tweak and tune before the show).  These are all SQ competitors only.  And they really don’t do justice to the number of cars that were actually competing over the weekend.

 

Kef Reference 207/2 10″ Woofer Driver

 Note: Above picture linked from Kef’s site.

 

IMG_6602 IMG_6600

 

A fellow sent me a set of the 10″ woofer drivers from Kef’s “flagship” 207/2 speaker for me to test recently.  One 207/2 costs $9,999 via Kef direct.  So, whoever was brave enough to dismantle… thank you.  😉

Below are my results.

Thiele-Small Parameters and Impedance

Electrical Parameters
Re 6.82 Ohm electrical voice coil resistance at DC
Le 0.662 mH frequency independent part of voice coil inductance
L2 1.014 mH para-inductance of voice coil
R2 4.3 Ohm electrical resistance due to eddy current losses
Cmes 428 µF electrical capacitance representing moving mass
Lces 64.93 mH electrical inductance representing driver compliance
Res 108.13 Ohm resistance due to mechanical losses
fs 30.2 Hz driver resonance frequency
Mechanical Parameters
(using add. mass)
Mms 48.44 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 40.801 g mechanical mass of voice coil and diaphragm without air load
Rms 1.047 kg/s mechanical resistance of  total-driver losses
Cms 0.573 mm/N mechanical compliance of driver suspension
Kms 1.74 N/mm mechanical stiffness of driver suspension
Bl 10.642 N/A force factor (Bl product)
Loss factors
Qtp 0.521 total Q-factor considering all losses
Qms 8.776 mechanical Q-factor of driver in free air considering Rms only
Qes 0.553 electrical Q-factor of driver in free air considering Re only
Qts 0.52 total Q-factor considering Re and Rms only
Other Parameters
Vas 103.7157 l equivalent air volume of suspension
n0 0.496 % reference efficiency (2 pi-radiation using Re)
Lm 89.16 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom 89.85 dB nominal sensitivity (SPL at 1m for 1W @ Zn)
Sd 357.53 cm² diaphragm area

207_2  woofer Magnitude of electric impedance Z(f)

 

Large Signal Analysis with Klippel’s LSI Suite

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=70% 8.2 mm Displacement limit due to force factor variation
X C @ C min=50% 8.2 mm Displacement limit due to compliance variation
X L @ Z max=17 % >8.9 mm Displacement limit due to inductance variation
X d @ d2=10% 39.3 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak 31.5 % Stiffness asymmetry Ak(Xpeak)
Xsym 0.57 mm Symmetry point of Bl(x) at maximal excursion

kef 207_2 woofer  Force factor Bl (X) kef 207_2 woofer  Bl Symmetry Range kef 207_2 woofer  Mechanical compliance Cms (X) kef 207_2 woofer  Stiffness of suspension Kms (X) kef 207_2 woofer  Kms Symmetry Range kef 207_2 woofer  Electrical inductance L(X, I=0) kef 207_2 woofer  Inductance over current L(X=0, I)

 

One nice plus is the relatively high sensitivity at just above 89dB @ 1w/1m.  The results show the woofer’s 20% THD limit is met by both motor and suspension at 8.2mm.  There is a near constant offset in Bl approximately 0.56mm forward.  There is a forward offset in suspension off approximately 1.0mm.  A shorting ring is used to keep inductance over excursion and inductance over current low, which is used to mitigate higher frequency distortion via intermodulation.

 

Funkin Audio FASX-380

 

 

 

IMG_6407 IMG_6408 IMG_6409

Up for test is a Funkin Audio FASX-380 15″ Subwoofer.  The sub is a dual 4ohm voice coil, though for this test only one coil was connected.

Thiele-Small Parameters

Electrical Parameters
Re 3.75 Ohm electrical voice coil resistance at DC
Le 0.312 mH frequency independent part of voice coil inductance
L2 1.962 mH para-inductance of voice coil
R2 12.84 Ohm electrical resistance due to eddy current losses
Cmes 1273 µF electrical capacitance representing moving mass
Lces 25.48 mH electrical inductance representing driver compliance
Res 13.25 Ohm resistance due to mechanical losses
fs 27.9 Hz driver resonance frequency
Mechanical Parameters
(using add. mass)
Mms 151.278 g mechanical mass of driver diaphragm assembly including air load and voice coil
Mmd (Sd) 127.892 g mechanical mass of voice coil and diaphragm without air load
Rms 8.968 kg/s mechanical resistance of  total-driver losses
Cms 0.214 mm/N mechanical compliance of driver suspension
Kms 4.66 N/mm mechanical stiffness of driver suspension
Bl 10.9 N/A force factor (Bl product)
Loss factors
Qtp 0.654 total Q-factor considering all losses
Qms 2.961 mechanical Q-factor of driver in free air considering Rms only
Qes 0.838 electrical Q-factor of driver in free air considering Re only
Qts 0.653 total Q-factor considering Re and Rms only
Other Parameters
Vas 172.4831 l equivalent air volume of suspension
n0 0.432 % reference efficiency (2 pi-radiation using Re)
Lm 88.55 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)
Lnom Zn missing dB nominal sensitivity (SPL at 1m for 1W @ Zn)
Sd 753.79 cm² diaphragm area

FA FASX-380 Magnitude of electric impedance Z(f)

 

Large Signal Analysis

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=70% 8.4 mm Displacement limit due to force factor variation
X C @ C min=50% >15.7 mm Displacement limit due to compliance variation
X L @ Z max=17 % 12.4 mm Displacement limit due to inductance variation
X d @ d2=10% 48.9 mm Displacement limit due to IM distortion (Doppler)
Asymmetry (IEC 62458)
Ak 47.66 % Stiffness asymmetry Ak(Xpeak)
Xsym 3.13 mm Symmetry point of Bl(x) at maximal excursion

FA FASX-380 Force factor Bl (X) FA FASX-380 Bl Symmetry Range FA FASX-380 Mechanical compliance Cms (X) FA FASX-380 Stiffness of suspension Kms (X) FA FASX-380 Kms Symmetry Range FA FASX-380 Electrical inductance L(X, I=0) FA FASX-380 Inductance over current L(X=0, I)