Blu-ray Forum - View Single Post - The Official Acoustic Audio Subwoofer Owners Thread

Big Daddy · 02-04-2009, 08:45 PM

Acoustic Audio HD-SUB12, 12" Powered Subwoofer, $198.88 + Free Shipping

Next, I opened the 12" sub box. My jaw dropped when I discovered the most beatiful cherry-colored cabinet. Immediately, I realized that this definitely has a high WAF appeal. It has the most gorgeous white driver and a high-end looking amplifier.

For a few minutes, I looked at the sub and appreciated its beauty. Can it perform as well as it looks? I took it to the home theater room, disconnected all other subwoofers and connected the new sub. I am not exaggerating. This thing can sound loud without distortion. I turned it up a little to test its tolerance. It scared me as I thought I was going to have a heart attack. Immediately, I decided that my sister can wait. This sub stays right here where it belongs. I ordered another one for her. I am so impressed with this new sub that I am willing to buy 4 of these for less than $800 and put each at the corner or the middle of each wall.

APPEARANCE

FREQUENCY RESPONSE

I decided to measure the frequency response of the HD-Sub 12 subwoofer. Unfortunately, a home theater room is not the best place for this type of measurements. The frequency response changes quite a bit in different locations in the room. I am also aware that the Audyssey calibration program has tweaked the subwoofer's frequency, but I am not trying to win the Nobel prize. Who wants to live in an anechoic chamber?

I took a few measurements and finally decided to take the readings about 3 ft (≈ 1 meter) directly in front of the subwoofer.

I turned the volume on the back of the subwoofer to the middle (50% point) and turned the subwoofer’s gain in the receiver to zero. The receiver's volume was intentionally set high in the 90dB range so that the measurements are calculated more accurately in case of weak sound output at some frequencies. All the other speakers and subwoofers in the room were turned off.

I played Rives Audio’s Test CD-2 test tones and measured the levels of the sound outputs at different frequencies with my Radio Shack Digital SPL Meter. At 25 Hz, the whole room, including all the furniture started vibrating like a real earthquake.

I must have hit the room resonance point.

I recorded the SPL numbers and then plotted SPL in dB’s versus frequency in Hertz using Microsoft Excel. The following graph demonstrates the results.

The subwoofer performs very well in the low and middle frequencies. After this point, the sound output begins to drop significantly. The reason is because the maximum level on the crossover network on the back of the subwoofer is set at 130Hz.

CONSTRUCTION

I opened my Acoustic Audio HD-Sub 12 subwoofer.

There is nothing special inside the subwoofer. Like most other subwoofers, the cabinet is made of 3/4" MDF wood with a layer of poly-fill on the inside walls. After I examined it thoroughly, I added some more poly-fill to it.

Here is a picture of the 12" driver. The wires are soldered for added security so that they don't come loose.

This is a picture of the amplifier. Unfortunately or I should say fortunately, it is completely taped up and you cannot see anything.

SPECIFICATIONS

Cabinet Finish: Cherry, Light Maple, or Black
Designed and Engineered in USA
Certified High Definition
Power Output: 400 Watts Nominal RMS to 800 Watts Maximum
Woofer: 12 Inch Front-Firing Long Throw Driver
Complex Fiberglass Cone
Aluminum Voice Coil Former
Parabolic RFL Voice Coil
CEA Cooling Technology
Vented and Extended Pole Piece
Low Carbon Top and Bottom Plate
Rear Slotted Bass Port
Frequency Response: 20Hz-250Hz
Bass Level / Gain Control
Line-Level and Speaker-Level Inputs
Line-Level and Speaker-Level Outputs for Adding Additional Subwoofers
Variable Low Pass Frequency Crossover: 40Hz-130Hz
Efficiency / Sensitivity: 99dB @ 1 watt/1 meter
Built-in Digital Drive High Efficiency Amplifier
Auto-On Signal Sensing Switch
Cabinet Design: Advanced RFL Bass Reflex
Cabinet Material: High-Density MDF
Grilles are Included
Dimensions (W x D x H): 14.9 x 15.5 x 17.4 Inches
3 Year Parts and Labor Warranty
Shipping Weight: 47 lbs
Suggested Retail Price: $699.99

This is the high Definition series sub from Acoustic Audio. Deep Discount sells other 8", 10", 12", and 15" Acoustic Audio subwoofers that are cheaper.

IMPORTANT CONSIDERATIONS

The more you play this subwoofer, the better this sub (like all others) will sound.
As you can see under specifications, the sensitivty of this subwoofer is high (99db @ 1 watt/1 meter) and the amplifier is too strong. The subwoofer can be extremely loud. It is best to keep the gain control (volume dial) on the subwoofer's amplifier around the midpoint. In my home theater room, I set it to less than the midpoint.
Do not forget that placement in the room plays an important role.

REVIEWS OF OTHER ACOUSTIC AUDIO SUBWOOFERS

The following review of Acoustic Audio HD-SUB10 is done by JJxiv1215:

http://forum.blu-ray.com/showpost.ph...&postcount=415
http://forum.blu-ray.com/showthread....07#post1841007

REPLACING THE DRIVER OF THE HD-SUB12 SUBWOOFER

As you can see in the picture above, the driver of the HD-SUB12 is quite attractive. I decided to do some experiments. I ordered the e3.12 from Elemental Designs for $125 + Free Shipping. This driver is used in the ED A2-300 subwoofers.

I replaced the original driver of the HD-SUB12 with the ED driver. When I took the AA driver out, I realized that there were several problems. Read the details in Post #399 of DIY Subwoofer/Speaker Building, Repairing, & Upgrading. This is a picture of the sub with the new driver.

I ran the Rives Audio test tones through the modified sub. To my surprise, it hardly produced any sound at 20Hz. My SPL meter registered 68dB. At 25Hz, the sound was louder around 87dB and they were louder after that. These are the overall responses at 1 meter (3.3ft) in my room:

20Hz, 68dB
25Hz, 87dB
31.5Hz, 97dB
40Hz, 97dB
50Hz, 88dB
63Hz, 92dB
80Hz, 94dB
100Hz, 92dB
125Hz, 92dB

This is the plot of SPL versus frequency.

You should not look at the absolute numbers in the above diagrams, but rather at the relative numbers. I intentionally drove the new ED driver a little lower because I was afraid of doing damage to something new and unfamiliar. Overall, I liked the performance of the new driver and am happy with it, but the original Acoustic Audio driver played much louder at 20Hz.

ADDITIONAL MEASUREMENTS

Last night (August 3, 2009), I ran test tones again to measure the output of the HD-SUB12 subwoofer. I took the measurements about 4 feet away and changed the level on the back of the sub and the receiver's volume. The gain for the sub in the receiver was held constant at zero.

Case 1. Sub level: 50%, Receiver Gain: 0, Receiver Volume: -15dB

20Hz, 74dB
25Hz, 92dB
31.5HZ, 99dB
40Hz, 98dB
50Hz, 92dB
63Hz, 92dB
80Hz, 97dB
100Hz, 86dB
125Hz, 81dB

This is the graph:

Case 2. Sub level: 75%, Receiver Gain: 0, Receiver Volume: -15dB

20Hz, 80dB
25Hz, 98dB
31.5HZ, 100dB
40Hz, 105dB
50Hz, 98dB
63Hz, 98dB
80Hz, 104dB
100Hz, 94dB
125Hz, 87dB

This is the graph:

Case 3. Sub level: 50%, Receiver Gain: 0, Receiver Volume: 0dB

20Hz, 94dB
25Hz, 101dB
31.5HZ, 101dB
40Hz, 108dB
50Hz, 105dB
63Hz, 104dB
80Hz, 105dB
100Hz, 96dB
125Hz, 92dB

This is the graph:

02-04-2009, 08:45 PM	#3 (permalink)
Big Daddy Home Theater Moderator Join Date: Jan 2008 Location: Southern California Trading Score: (0) Collection: (77) HT Gallery: (73)	Acoustic Audio HD-SUB12, 12" Powered Subwoofer, $198.88 + Free Shipping Next, I opened the 12" sub box. My jaw dropped when I discovered the most beatiful cherry-colored cabinet. Immediately, I realized that this definitely has a high WAF appeal. It has the most gorgeous white driver and a high-end looking amplifier. For a few minutes, I looked at the sub and appreciated its beauty. Can it perform as well as it looks? I took it to the home theater room, disconnected all other subwoofers and connected the new sub. I am not exaggerating. This thing can sound loud without distortion. I turned it up a little to test its tolerance. It scared me as I thought I was going to have a heart attack. Immediately, I decided that my sister can wait. This sub stays right here where it belongs. I ordered another one for her. I am so impressed with this new sub that I am willing to buy 4 of these for less than $800 and put each at the corner or the middle of each wall. APPEARANCE FREQUENCY RESPONSE I decided to measure the frequency response of the HD-Sub 12 subwoofer. Unfortunately, a home theater room is not the best place for this type of measurements. The frequency response changes quite a bit in different locations in the room. I am also aware that the Audyssey calibration program has tweaked the subwoofer's frequency, but I am not trying to win the Nobel prize. Who wants to live in an anechoic chamber? I took a few measurements and finally decided to take the readings about 3 ft (≈ 1 meter) directly in front of the subwoofer. I turned the volume on the back of the subwoofer to the middle (50% point) and turned the subwoofer’s gain in the receiver to zero. The receiver's volume was intentionally set high in the 90dB range so that the measurements are calculated more accurately in case of weak sound output at some frequencies. All the other speakers and subwoofers in the room were turned off. I played Rives Audio’s Test CD-2 test tones and measured the levels of the sound outputs at different frequencies with my Radio Shack Digital SPL Meter. At 25 Hz, the whole room, including all the furniture started vibrating like a real earthquake. I must have hit the room resonance point. I recorded the SPL numbers and then plotted SPL in dB’s versus frequency in Hertz using Microsoft Excel. The following graph demonstrates the results. The subwoofer performs very well in the low and middle frequencies. After this point, the sound output begins to drop significantly. The reason is because the maximum level on the crossover network on the back of the subwoofer is set at 130Hz. CONSTRUCTION I opened my Acoustic Audio HD-Sub 12 subwoofer. There is nothing special inside the subwoofer. Like most other subwoofers, the cabinet is made of 3/4" MDF wood with a layer of poly-fill on the inside walls. After I examined it thoroughly, I added some more poly-fill to it. Here is a picture of the 12" driver. The wires are soldered for added security so that they don't come loose. This is a picture of the amplifier. Unfortunately or I should say fortunately, it is completely taped up and you cannot see anything. SPECIFICATIONS Cabinet Finish: Cherry, Light Maple, or Black Designed and Engineered in USA Certified High Definition Power Output: 400 Watts Nominal RMS to 800 Watts Maximum Woofer: 12 Inch Front-Firing Long Throw Driver Complex Fiberglass Cone Aluminum Voice Coil Former Parabolic RFL Voice Coil CEA Cooling Technology Vented and Extended Pole Piece Low Carbon Top and Bottom Plate Rear Slotted Bass Port Frequency Response: 20Hz-250Hz Bass Level / Gain Control Line-Level and Speaker-Level Inputs Line-Level and Speaker-Level Outputs for Adding Additional Subwoofers Variable Low Pass Frequency Crossover: 40Hz-130Hz Efficiency / Sensitivity: 99dB @ 1 watt/1 meter Built-in Digital Drive High Efficiency Amplifier Auto-On Signal Sensing Switch Cabinet Design: Advanced RFL Bass Reflex Cabinet Material: High-Density MDF Grilles are Included Dimensions (W x D x H): 14.9 x 15.5 x 17.4 Inches 3 Year Parts and Labor Warranty Shipping Weight: 47 lbs Suggested Retail Price: $699.99 This is the high Definition series sub from Acoustic Audio. Deep Discount sells other 8", 10", 12", and 15" Acoustic Audio subwoofers that are cheaper. IMPORTANT CONSIDERATIONS The more you play this subwoofer, the better this sub (like all others) will sound. As you can see under specifications, the sensitivty of this subwoofer is high (99db @ 1 watt/1 meter) and the amplifier is too strong. The subwoofer can be extremely loud. It is best to keep the gain control (volume dial) on the subwoofer's amplifier around the midpoint. In my home theater room, I set it to less than the midpoint. Do not forget that placement in the room plays an important role. REVIEWS OF OTHER ACOUSTIC AUDIO SUBWOOFERS The following review of Acoustic Audio HD-SUB10 is done by JJxiv1215: http://forum.blu-ray.com/showpost.ph...&postcount=415 http://forum.blu-ray.com/showthread....07#post1841007 REPLACING THE DRIVER OF THE HD-SUB12 SUBWOOFER As you can see in the picture above, the driver of the HD-SUB12 is quite attractive. I decided to do some experiments. I ordered the e3.12 from Elemental Designs for $125 + Free Shipping. This driver is used in the ED A2-300 subwoofers. I replaced the original driver of the HD-SUB12 with the ED driver. When I took the AA driver out, I realized that there were several problems. Read the details in Post #399 of DIY Subwoofer/Speaker Building, Repairing, & Upgrading. This is a picture of the sub with the new driver. I ran the Rives Audio test tones through the modified sub. To my surprise, it hardly produced any sound at 20Hz. My SPL meter registered 68dB. At 25Hz, the sound was louder around 87dB and they were louder after that. These are the overall responses at 1 meter (3.3ft) in my room: 20Hz, 68dB 25Hz, 87dB 31.5Hz, 97dB 40Hz, 97dB 50Hz, 88dB 63Hz, 92dB 80Hz, 94dB 100Hz, 92dB 125Hz, 92dB This is the plot of SPL versus frequency. You should not look at the absolute numbers in the above diagrams, but rather at the relative numbers. I intentionally drove the new ED driver a little lower because I was afraid of doing damage to something new and unfamiliar. Overall, I liked the performance of the new driver and am happy with it, but the original Acoustic Audio driver played much louder at 20Hz. ADDITIONAL MEASUREMENTS Last night (August 3, 2009), I ran test tones again to measure the output of the HD-SUB12 subwoofer. I took the measurements about 4 feet away and changed the level on the back of the sub and the receiver's volume. The gain for the sub in the receiver was held constant at zero. Case 1. Sub level: 50%, Receiver Gain: 0, Receiver Volume: -15dB 20Hz, 74dB 25Hz, 92dB 31.5HZ, 99dB 40Hz, 98dB 50Hz, 92dB 63Hz, 92dB 80Hz, 97dB 100Hz, 86dB 125Hz, 81dB This is the graph: Case 2. Sub level: 75%, Receiver Gain: 0, Receiver Volume: -15dB 20Hz, 80dB 25Hz, 98dB 31.5HZ, 100dB 40Hz, 105dB 50Hz, 98dB 63Hz, 98dB 80Hz, 104dB 100Hz, 94dB 125Hz, 87dB This is the graph: Case 3. Sub level: 50%, Receiver Gain: 0, Receiver Volume: 0dB 20Hz, 94dB 25Hz, 101dB 31.5HZ, 101dB 40Hz, 108dB 50Hz, 105dB 63Hz, 104dB 80Hz, 105dB 100Hz, 96dB 125Hz, 92dB This is the graph: Last edited by Big Daddy; 08-05-2009 at 12:48 AM.