SVS SB-1000 Subwoofer Review:
</SPAN></SPAN>Kudos to SVS and Ed Mullen for sending me the SB-1000 to review and putting up with all my questions over the past several weeks!</SPAN>
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FED EX Tracking Number: 2215126003XXXX
</SPAN></SPAN></SPAN></SPAN>Knowing that a SVS subwoofer is on its way reminds me of the days of being a kid with Christmas day right around the corner. The way that the hours creep past: looking at the clock every 4 hours and seeing that only 5 minutes have actually passed. At last, the FedEx package arrives!
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The package is nice and heavy… </SPAN>37 lbs. I want to tear into the box and unwrap it like a little kid, but taking careful steps, opening box after box, I finally set it FREE from it’s protective shell. </SPAN></SPAN>
The basic specs are pretty impressive in such a small (13” square) package:</SPAN></SPAN>
- 12” lightweight cone driver – Really? Wow! SVS put in a massive driver in this small box! </SPAN></SPAN></SPAN>
- 300 watts RMS class D – Sledge STA-300D – High Efficiency Power Supply</SPAN></SPAN></SPAN>
- Frequency response: 24-260Hz +/- 3dB – Real Bass! What I want in a subwoofer…</SPAN></SPAN></SPAN>
- 27 lbs - Superlight!</SPAN></SPAN></SPAN>
But what does that mean to me?
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One Happy Kid!</SPAN></SPAN>
What these specifications REALLY meant to me is that as soon as I got the SB-1000 set up, my wife, 4 year old son, and I spent 2 hours straight listening to music and dancing in the living room. It was a great family night… and goes to show how nice this sub is. The WAF factor is very high: the SB-1000 is very nice looking and compact enough to be out of the way. I did an ugly job running the cables… and surprisingly my wife STILL hasn’t called me on that! So that REALLY shows you how appreciative she is of the system.
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Ok… I’m an engineer I NEED to break down the Specs:</SPAN></SPAN>
12” Driver</SPAN> - The lower the frequency produced, the more air the driver’s cone has to move to maintain the dB output, so having a large, lightweight 12” cone along with the short throw suspension (same package size as an 8” sub) allows the SB-1000 to maintain a constant dB level at far lower frequencies. The 12” driver has very high sensitivity, so even with only 300 Watts; it can provide very high SPL at low frequencies. This shows up clearly in the frequency response: 24Hz lower limit vs. a typical 10” sub’s 38Hz lower limit.</SPAN></SPAN>
Class D</SPAN> - Compared to a class D amp design, classes A, AB, and B have high power dissipation in the output-stage. A Class D is over 85% energy efficient which is impressive when you compare it to a Class AB which is normally only 25% efficient. That means less heat, weight, and space for the power supply. Class D amps work by forcing the output transistors to switch between positive and negative power supplies producing a pulse waveform. The output transistors have zero current when not switching, and low voltage when they are conducting current, leading to lower energy losses.</SPAN></SPAN>
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Class</SPAN> AB</SPAN> vs. Class D topology comparison – Source EEtimes.com</SPAN></SPAN>
The SVS-1000 amp goes one step further with high-quality MOSFETs and a 50 kHZ switched-mode power supply to further improve efficiency, which it turn results in a more compact and lighter amplifier with no reduction in performance. In order to make the subwoofer even greener, SVS decided to lower standby power to less than 0.5 watts (IEA, IEC 62301, and EN 50564:2011 compliant). With the auto-on mode, the subwoofer can be switched on all day, ready to go, without impacting your electric bill!</SPAN></SPAN>
Frequency Response down to 24Hz: </SPAN>The pulse-width modulator which converts the audio input adds high frequency energy to the desired audio signal as part of the process. The SB-1000 has a DSP which SVS uses to create a precise EQ curve. The EQ curve includes a high pass filter on the low-end, PEQ filters in the mid-band, and a low pass filter (not to be confused with the user adjustable cross-over filter) on the high-end. Because these filters are developed and implemented in the digital domain, SVS can precisely cut and boost frequencies in the subwoofer response to maintain the linear, smooth, and accurate frequency response from 260Hz down to 24Hz.
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</SPAN></SPAN>SB-1000 response curve at 2 meter ground plane
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The DSP also features a frequency-dependent limiter/compressor algorithm with adjustable and extremely fast attack/release and gain compression parameters. The end result is very refined behaviour at the drive limits of the subwoofer system, with no audible overdrive artefacts.</SPAN></SPAN>
What makes this interesting is that many competitive subwoofer manufactures do not use DSPs; they attempt to implement filters and limiters in an analog system, which significantly reduces their precision in adjustment, limiting the quality of their EQ system. This also means that the limiting filters can be “beat” by transients in source material which leads to artifacts, or even damage to the subwoofer. Even worse, some subwoofers don’t have any EQ systems. With a non-linear driver, those kinds of subwoofers are just loud boom boxes.</SPAN>
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SVS measured FE, maximum output with 6.5 cycle shaped tone burst at 1/3 octave spacing (per CES-2010). They then used that information to develop a preliminary flash file for the DSP. Then they took in subwoofer indoors and tested it with a variety of source material for sound quality, accuracy, musicality, tightness, and perceived transient response/overhang, deep extension, slam, impacts, etc. Based on the behavior the flash file was tweaked and is unique to the SB-1000. </SPAN></SPAN>
SVS Quality:</SPAN> The SB-1000 was designed to be the highest performance, compact, subwoofer available for $499. SVS spent 1-1/2 years developing the SB-1000, running though QA/QC testing including:</SPAN></SPAN>
·</SPAN> Electrical functionality/safety tests and certifications</SPAN></SPAN>
·</SPAN> Long-term reliability and durability testing for both amplifiers and drivers</SPAN></SPAN>
·</SPAN> Temperature, humidity, vibration testing</SPAN></SPAN>
·</SPAN> shipping package durability/drop testing</SPAN></SPAN>
·</SPAN> Frequency response compliance against gold standard</SPAN></SPAN>
·</SPAN> Max output compliance against gold standard</SPAN></SPAN>
·</SPAN> Distortion levels against gold standard</SPAN></SPAN>
·</SPAN> rub/buzz/artifacts</SPAN></SPAN>
·</SPAN> limiter/compressor function</SPAN></SPAN>
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Now it time</SPAN></SPAN> to see what this thing can do!
I have a Pioneer VSX-1022 Receiver, 2 Aperion Versus Grand Bookshelf speakers, and the SB-1000 sub. The SB-1000 is a perfect sub for small rooms with the 13” box dimensions. One of its other advantages in a small room is the lack of a port. Ported subs help with lower frequency extension, but ports have the disadvantage of making noise at their natural frequency (which is normally above 200Hz). With a smaller room, mini speakers are popular, but require cross-overs so high that the subwoofer port’s natural frequency could be in the operating range. Thankfully, I don’t use mini-speakers! </SPAN>
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I recalibrated the system using Pioneers self calibration, which recommended a 100Hz cross over. SVS’s Merlin cross-over calculator also recommended 100Hz, but Ed Mullen at SVS explained how Merlin works. “Merlin is the product of our best judgment as to the typical room size when a type of speaker is used. So a smaller room or quieter listening levels may allow a cross over to be lower than our recommendation.” Ed recommended I set the cross over to 80Hz. He stated that he likes to have center channels and bookshelves to be large enough to handle a 60Hz cross over so that male voices are still handled by the speakers, which keeps the voices from seeming disembodied. I set the Pioneer cross over to the recommended 80Hz and the size to Small.</SPAN></SPAN>
I used Room EQ Wizard - REW V5 (</SPAN>
www.hometheatershack.com/roomeq</SPAN>) freeware to measure the room acoustics </SPAN>and subwoofer responses. I calibrated by leveno X201 laptop sound card, and downloaded a generic calibration file for </SPAN></SPAN>my RadioShack SPL meter (model 33-2055). Using the calculation speed of sound (1186 ft/s at 70F and 700’ alt) divided by distance (in ft); I figured that the room’s prime nodes would be at 148Hz, 99Hz, and 59Hz.
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Living Room – 8’ Ceilings
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</SPAN>Initial Frequency Response – BIG null at 50-60Hz </SPAN></SPAN>
Actually measuring the room’s response showed that my main nulls were at the predicted Hz (CRAZY, a calculation that actually works?). With this frequency response in hand, I knew I had a serious problem. With the cross over at 80Hz, I wasn’t worried about the null that started at 90Hz, but 50-60Hz is a key area for music and movies. It is above the normal male voice (85Hz-180Hz – Wikipedia), but certainly something had to be done. Moving the sub wasn’t really an option, but moving the listening area slightly was. With that, I was able to reduce the effect of the null (Final jpg not yet available). Still that leaves us with high frequency responses at 30Hz, and 80Hz. After a discussion with Ed Mullen (SVS), he told me that even though Audyssey was designed to deal with that, there is a DIY way as well. With the use of a Feedback Destroyer, such as Behringer FBQ1000 ($150 anywhere), and REW, one can create a manual PEQ to even out all of the frequencies. I haven’t had the opportunity to attempt this, but it seems like a great option for those without an Audyssey system and a reasonable investment. </SPAN></SPAN>
SO HOW DOES IT SOUND?</SPAN></SPAN>
Wow! You got this far? REALLY? Cool! Because the SB-1000 is an awesome subwoofer. It makes music and music really have PUNCH. The deep bass extension creates a physical impact when you listen to music and movies. The capability of this subwoofer blows away every other compact sub I’ve ever tried. Basically, if you want a SUB that is a MONSTER, you are looking at the wrong system. But, if you want a sub, something that you don’t have to compromise on performance, but don’t want to have your whole room dominated by something that is bigger than your couch, then this is your system. It is a great PC or gaming system… but where it really shines is in the apartment or room that your wife has said – NO WAY! I could fit the SB-1000 anywhere. It fits on a desk, it fits in the corner behind the couch, and it hides like a little rabbit with sound like a lion’s roar! I can turn up this system, and walk all the way into the garage and still appreciate this sub’s accurate BASS. I recommend it highly.</SPAN>
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Sources: </SPAN></SPAN>
SVS’ Ed Mullen</SPAN></SPAN>
EEtimes.com, What’s behind Class D audio amplifiers, Eric Gaalaas – Analog Devices, 1/22/2007</SPAN></SPAN>
EEtimes.com, Class D Audio Amplifiers: What, Why, and How – Part 4, Eric Gaalaas – Analog Devices, 1/24/2007</SPAN></SPAN>
EEtimes.com, Product How-To: 350W+ 350W Class D power amp in the size of an iPod, Jun Honda, Yasushi Nishimura, and Liwei Zheng, 8/23/2011</SPAN></SPAN>
EEtimes.com, Subwoofer design: Overcoming common performance issues – Part 1, Jim Thiel 10/3/2007</SPAN></SPAN>
EEtimes.com, Subwoofer design: Overcoming common performance issues – Part 2, Jim Thiel 10/10/2007</SPAN></SPAN>
EEtimes, DSP drives Velodyne subwoofers, Henry Davis, 10/17/2005</SPAN></SPAN>
Wikipedia – Voice Frequency</SPAN></SPAN>