Power Sound Audio XV15 Subwoofer Review

Power Sound Audio XV15 Subwoofer Introduction

The XV15 subwoofer sits in the middle of the three model Power X lineup offered by Power Sound Audio which has just started shipping product as of summer 2012. Power Sound may be a new name in the world of powered subwoofers but its founders Tom Vodhanel and Jim Farina are no newcomers to the internet direct subwoofer market. Both men played key roles at SVS in a past life. In fact Tom is the “V’ in SVS. Needless to say considering the experience that these two possess there is a certain amount of expectation from their new product line. Their Power X line includes a compact sealed 15” the XS15, the XV15 vented subwoofer reviewed here, and a top dog XV30 which is a dual vented 15” brute. The goals for the Power X line are maximum performance and sound quality for a very reasonable price. Additionally all of the parts and assembly of the subwoofers take place here in the U.S. except for the amplifiers which proved difficult to source while maintaining a reasonable cost. Power Sound also goes to the effort of posting some measurement data on their subwoofers on their website including things like basic response and CEA-2010 averages which is rare.

The XV15 is the middle child of the line-up, a 92lb, 15” vented subwoofer motivated by a 500w plate amplifier that carries a price tag of just $799 with shipping included. It is said to deliver response down below 20Hz in room. The XV15 is delivered in a very large and very heavy box that probably weighs in total around 110lbs and likely just squeeks under the limits set by the major carriers for regular ground shipping. Opening the top revealed that the packaging consists of a single heavy gauge outer box with the XV15 suspended away from the outer surfaces by eight large and stiff foam corner protectors of roughly 2” thickness. The XV15 is further protected by a thick plastic bag that has the accessory pack containing the power cord and the owner manual taped to the top of it. Removal of the XV15 from the box and involves the usual opening of the top followed by removing the accessory pack and flipping the box onto its top, from where the box can be lifted off, the foam corner pieces removed from under the subwoofer and finally the bag untapped and lifted off. Truthfully this is not the most robust packaging I have ever seen on a unit of this size and weight. But the unit did arrive in good condition.

After lugging the XV15 into my theater room I was grateful that the port and base plate provided convenient hand holds for carrying. It is manageable by one guy but moving it would be a lot easier with two. At first judging from the pictures online that I had seen I assumed that the XV15 finish would be a very rough black finish similar to truck bed-liner. Very durable and tough but not very civilized. On that account I was wrong. The finish, which is described by Power Sound as a “sand” texture, is much better looking than I thought it would be. It is a dark, slate gray/black that has a very smooth texture similar to a fine grit sand paper and is almost satin in appearance. It looks much better in person than in the pictures. Don’t get me wrong this is no furniture grade finish that you will yearn to put on prominent display. This will be a large subwoofer to most and it is a basic, square, black object. But that said the finish is well applied, is of high quality and should disappear into a dark room easily.

Design Overview

The XV-15 is a bass reflex design utilizing a single 15” down firing long throw woofer loaded into a base plate and a 4” heavily flared port which fires from the back panel where the amplifier is also mounted. Firing the driver downwards into the base plate can band pass load the output of the driver slightly and increase the output in the upper bass frequencies by a small amount. Additionally arranging the driver this way also serves to protect it from mishaps and small critters or children. Judging from the measurements shown later and the information from Power Sound the tuning of the vent system is somewhere in the 18Hz range.

The 15” driver used in this system is constructed on a 12 spoke cast aluminum frame and uses a heavy pressed paper fiber cone with an inverted dust cap. The surround is a large half roll of Rubatek foam which should allow generous excursions. The voice coil is a 2” diameter copper flat wind with an 8” poly cotton spider providing centering and returning force. The motor is comprised of a triple stack of y35 grade magnets of about 5” diameter and a vented pole piece to remove heat from the gap. This driver appears to be sturdy, heavily built for a subwoofer selling in this price class and capable of withstanding large excursions. Power Sound indicates that the driver is capable of 2” peak to peak stroke.

Power Sound Audio XV15 Driver

The amplifier of the XV-15 is a lightweight and efficient Class D BASH hybrid type that is said to combine the best of class AB and class D topologies and is rated at 500 watts rms and 1000 watts peak output. The amplifier is Energy Star compliant and in standby mode is said to consume only 1 watt. In use the amplifier seemed to be very efficient as claimed as it barely even got warm to the touch even while being subjected to high duty cycle test signals. The inputs provided consist of a pair of RCA style unbalanced connections with the left input marked as the LFE, and no outputs of any kind. Controls consist of the input sensitivity, phase, low pass filter and auto/on/off selector only. Additionally Power Sound mentions a laundry list of advanced protection and tuning circuits in this amplifier design: Thermal, DC offset, short circuit and load protections, plus driver current and voltage monitoring and advanced frequency specific compression.

Power Sound Audio XV-15 Back View

The XV15 enclosure is constructed of CNC cut 1” MDF panels and a 1.5” thick base plate. The lone finish available is a dark, fine textured black that is quite durable and resistant to smudges, scratches and fluids. The base plate attaches to the top section of the enclosure by 4 legs which have a bolt passing through them to tighten the pieces together. The port extends deeply into the enclosure interior to within a few inches from the opposite wall and is flush mounted as is the amplifier plate. The driver is not flush mounted but being under the enclosure and very seldom seen there really wouldn’t be much point to it anyway. Internally the enclosure is lined with what looks like fiberglass insulation. Unfortunately while the amplifier was removed and the interior of the enclosure was inspected I neglected to actually take any pictures! The XV15 never showed any signs of enclosure panel vibration, rocking or any noises related to internal resonances or vibration when probed with high power test signals outdoors. It was inert throughout. The XV15 is a very solidly constructed subwoofer as evidenced by the 92lb weight and the components are all of excellent quality for this price range. I am a bit baffled by how Power Sound has managed to assemble this subwoofer in the U.S. with primarily U.S. components and managed to ship the 92lb sucker all for $799 while still making some sort of profit for themselves.

Power Sound Audio XV15 Subwoofer Listening Session

For all of the listening sessions the XV15 subwoofer was placed in the front right corner of the room with the port about 5 inches from the wall. This places the subwoofer about 4 meters from the primary listening position. I have determined this to be the best available single subwoofer placement in the room for most units. Audyssey was run on the system to allow it to integrate the XV-15, which was then followed by a check and recalibration of the subwoofer and speaker levels prior to the listening sessions. It is assumed that the majority of purchasers would utilize some form of automated room correction system to integrate a new subwoofer hence running the auto equalization routine. The XV-15’s internal low pass filter was defeated in favor of a 100Hz internal one inside of the Onkyo PR-SC886P processor.

Editorial Note: I have recently moved into a new home and have a listening room that is significantly different from my previous one. The new room is a smaller 3150 cubic ft but open to a large hallway connecting to the rest of the basement with a shorter ceiling and more complex shape. Additionally it is a cement slab floor with 3 walls of brick as opposed to the larger, wood frame and floor constructed room I had been in previously. This room is easier to drive than the old space but has much less tactile transmission so I now use a higher -10 master volume setting for movie playback instead of -15.

Music Listening

As usual I started off by listening to a variety of music once the XV-15 was integrated into the system. I like to start with familiar music to get a feel for how the subwoofer is blending with the rest of the system and how linear its response is. Filter’s 2002 release Amalgamut is a well produced pop/rock album which I know very well having a hefty dose of sub 40Hz content and the occasional synthesized bass tone underneath of the drums and bass guitar. On tracks such as "Where Do We Go from Here" and "It Can Never Be the Same" the XV15 produced a palpable kick drum fundamental with a clean attack, and the weightier than average tone of the bass guitar mix on this album, with fantastic presence. The definition of individual tones in the upper bass region were, clear, distinct and it was difficult to tell where the XV15 trailed off and the main speakers took over. The occasional synthesized bass effect was reproduced with ease and no sense of strain at spirited output levels that were vibrating the furniture. Listening to Clockwork Angels the latest release from Canadian power trio Rush with the XV-15 run quite a few clicks hotter than the mains (For that authentic concert feeling.) only further reinforced the impression of power and neutrality. Having just attended a live Rush concert where this album was performed in its entirety, I found the XV-15 capable of producing a fairly convincing impression of the bottom end of the massive concert PA in my much smaller domestic sized room. I would give the XV-15 the edge on pitch delineation and neutrality versus the live event though. I also ran a few tracks from the N.I.N. album The Slip at house party levels to see how the XV15 would cope with loud electronic bass. It did not disappoint. The kick drum was satisfyingly big and room filling during Discipline and when the upwards sine sweep comes in during the break towards the end of the song the XV15 produced it powerfully and with the deep bass at the start of the sweep intact indicating response to below 20Hz. This was further confirmed on The Four of Us are Dying which has content down below 20Hz throughout much of the track. Many subs either miss this deep content or are overdriven trying to reproduce it, not the XV15.

Blu-ray Movies

Having satisfied myself that the XV15 was suitably neutral and refined without major acoustic issues listening to music, it was time to test the XV15’s metal with a dose of over the top Hollywood style bass. With it being close to Halloween I decided to go with movies that were appropriate for the season. Monster House is an animated film intended for younger audiences that has long been one of my favorites of the genre, in large part due to the excellent surround mix. Throughout most of the film there is bass that is sprinkled in as needed for scare factor, feelings of dread and background music, in between the usual bumps and slams of doors, etc. Whenever the house starts to transform is a different story and is accompanied by prodigious bass content that is quite taxing for many subwoofers. The final climactic scenes involving the house are incredibly bass heavy and involve content extending to below 20Hz. The XV15 easily handled everything through the first half of the movie with and when the final sequence got underway it produced room filling, thundering bass as the monster lifts off of its foundation and attacks the kids. There was enough bass that I paid a little bit of extra attention to the XV15 to make sure that it wasn’t distorting or in danger. It was not but a glance at it revealed that the driver was going crazy. If the XV-15 was hitting its limit during this I do not know, but if so there was nothing audible to indicate it, as all I heard were impressive amounts of deep bass output. There was even a hint of the underwater pressure on the ears sensation that sub bass at loud volume will give. Movie number two on the viewing list was the horror/suspense movie Pulse. This is admittedly not my favorite movie but it does have fantastic amounts of bass useful to demo any sub system. Once again the XV-15 was equally up to the task of providing ominous background rumbles, the low register of music in the soundtrack and abrupt bass transients used as queue’s to go with the on screen action in an effort to make you jump out of your seat. The server room scene in this movie is notoriously difficult for most subwoofers to handle as it contains a loud, sustained, pulsed 16Hz signal with not much masking content going in on the rest of the speaker channels. Most subwoofers will either not reproduce the signal at all by filtering it away or they will be overloaded badly at a loud playback level. The XV15 proved it is capable of output this low in room and managed enough output during this scene to shake some things in the room while not being obviously over loaded. However there was some accompanying audible port noise during this scene. This was the only time during the listening session that port noise was heard. One XV-15 is quite capable and will probably be sufficient for many rooms, however with the bargain pricing one will likely start to wonder how much more fun a pair would be. I know I did.

Power Sound Audio XV15 Subwoofer Measurements and Analysis

The XV15 was placed outdoors in a large field with the nearest large objects a minimum of 60ft or greater away from it, with the amplifier and port facing towards the microphone and the driver down firing as per normal orientation in room. The LFE input was used and the measurement microphone was placed on the ground at a distance of 2 meters from the nearest enclosure face of the XV15 and pointing directly at it unless otherwise specifically noted for all measurements. For more info on the testing equipment and procedures please see the article here.

Powered Subwoofer Testing Outline and Procedures Overview

Power Sound Audio XV-15: Effect of Low Pass Filter Settings

Above are measurements of the Power Sound XV15 with various settings of the internal low pass filter. Minimum, maximum, bypassed and at settings on the dial that correspond to the 9, 11, 1 and 3 o’clock positions on a clock. The filter roll off corresponds to about 45Hz at the minimum and 150Hz at the maximum settings and a roll off of 24dB/octave. This is a plenty wide range to accommodate most situations if the low pass filter in the subwoofer needs to be used.

Power Sound Audio XV-15: Basic Frequency Response as Tested

The response shape of the XV15 conforms pretty closely to that shown in the manufacturers graph but has a slight hump in response centered at 80Hz which is not present in theirs. This may be due to production variance in the drivers in the subwoofers or measurement and equipment differences. It is hard to know. Regardless it is not a large enough difference to be concerned with. Overall the response shape as measured here fits within a 6dB total window from 21-200Hz matching the listed spec exactly. The blip in response just above 200Hz is likely to be the port resonance. The response gradually and slowly trails off on the bottom end until about 7dB down at 18Hz and 10dB down at 16Hz. This response shape indicates that the subwoofer can be used low passed as high as 150Hz or potentially even higher if needed and that typical room gain should counteract the shallow roll off towards the low end to produce a flatter response. Indeed response to the 16Hz range in room is quite probable.

Power Sound Audio XV15: Group Delay

Power Sound Audio XV15: Water Fall Decay

The group delay plot for the XV15 shows good behavior with less than 1 cycle of delay until below 20Hz where it just breaks the 1 cycle mark at around 16Hz. It is very doubtful that anyone would be able to hear small differences in delay at such deep frequencies so the increase below 20Hz is of little consequence. Looking at the data presented another way in the waterfall plot indicates that the XV15 exhibits clean and rapid loss of 25dB of energy over most of its bandwidth within the first 150ms. As seen in the group delay plot the port tuning and high pass filter produce a little delayed energy below 25Hz. However the XV15 is rather well behaved in this regard compared to many other bass reflex systems.

Power Sound Audio XV15: Long Term Power Compression

Running the XV15 through the gauntlet of long term output compression testing provides the results in the graph above. The XV15 maintains excellent output uniformity through the 105dB sweep with less than 2dB over most of the range, but the 110dB sweep shows notable compression in the deep bass and signs that the limiter may have kicked in. This being a new product from a new company entering the market I wanted to see if they had done their homework with the protection circuits so the level was increased a further 5dB and a 115dB sweep was attempted. It resulted in little extra output indicating that the sub was clearly giving all that it could but otherwise it operated as normal and was unharmed. During the 110 and 115dB sweeps there was some port noise noted during the sweeps and the driver made a few grumbles during the 115dB sweep. This may have been the limiter heavily intervening near the port tuning as you can see the loss in output compared with the 110dB sweep near 18Hz. Otherwise there was no cabinet vibration or rattles and the XV-15 was inert throughout the testing. The XV15 exhibits substantial output during this test with roughly 110dB available from 40-90Hz and protection circuits that prevent any damage to the system from over-zealous knob jockeys.

Note on Output Compression Testing: This is by far the most demanding measurement type conducted on the subwoofers during our testing and will reveal any issues with overload, port compression, port noise, driver distress, creaks, rattles, buzzes, etc. Additionally the test is conducted outdoors with just the subwoofer operating so there will be no nearby walls or objects to vibrate and no upper frequency content from other speakers in operation. These would normally help to cover up or mask any objectionable noises from the subwoofer in a typical room. Any sort of audible distress or issues with the subwoofer are readily apparent in this environment.

Power Sound Audio XV15: Output Compression Magnitude

Looking at the only amount of compression exhibited by the XV15 during the compression testing it again can be shown that the sub was linear up through the 105dB sweep but was out of output completely by the 115dB sweep. The largest compression occurs near 18Hz and combined with the behaviors seen in a few other tests indicates that this is likely the tuning of the vent system in this subwoofer. Some compression of the output near vent tuning and a bit of port noise at full output is not unexpected with a single 4” port tasked with coping with a long throw 15” driver. However the flaring helps out a lot and other than with the certain scene in the movie Pulse I never heard any port noise during listening.

Power Sound Audio XV15: Total Harmonic Distortion

Power Sound Audio XV15: Distortion by Component

The distortion results for the XV-15 are shown above. THD is under control during the 100dB sweep and is under 10% over the subs entire useful range. By the 110dB sweep where the unit is being pushed very hard THD has grown drastically and reaches about 30% at 20Hz and 15% or more near 100Hz. However over the critical 25-80Hz bandwidth THD is still well below 10% for the most part. Looking at the component makeup of the distortion reveals that the THD is primarily composed of the second harmonic over virtually the entire bandwidth of this subwoofer. The general belief is that the second harmonic is the hardest to hear and the least offensive to the ear.

Power Sound Audio XV15: CEA2010 2 Meter Groundplane RMS Results

Power Sound Audio XV15: CEA2010 2 Meter Groundplane RMS Graph

CEA2010 Results

The CEA2010 burst testing results for the XV-15 indicate that it offers a substantial amount of headroom for this price class of product. At 10 and 12.5Hz a passing output could not be recorded but at 16Hz the XV15 mustered up 98.1dB and at 20Hz 102.7dB so the XV15 has credible deep bass output capabilities into the 16Hz range. In room this output will usually see some positive reinforcement as well. From 31.5 to 100Hz the XV15 produces roughly 110dB or more. At 50Hz an SPL of 116.6dB which is getting to be loud indeed was recorded. The distortion profile follows the same trend as that shown in the distortion charts with increased distortion in the deep bass and around tuning and above 80Hz.The XV15 CEA-2010 output is amp limited from 25-125Hz and essentially is at 16 and 20Hz as well as the output meets the distortion thresholds at right about the same time as the limiter circuit clamps further increases in output. Power Sound tests their subs for CEA-2010 output internally and lists some of the information on the website. Comparing the averaged CEA-2010 output measured over 20-31.5Hz and 40-63Hz with that listed by PowersSound, shows that their listed results are a little higher, but still within 1.5dB which is well within the margin of error due to variance in: Production, equipment, calibration tolerance and atmospheric conditions.

Power Sound Audio XV15 Subwoofer Conclusion

Power Sound has come out swinging with the XV15 and if the rest of their line-up is as good as the XV15 is I’d expect they will be doing quite well for themselves in their first year of operation. The previous experiences that the founders of Power Sound had producing powered subwoofers is evident in the XV15 in the protection circuits, the internal equalization and the overall design. It is not a small sub or the prettiest on the block but there are plenty of choices that fit into that mold and that market segment is not who this subwoofer was designed for to begin with. Don’t get me wrong I actually liked the finish and look of the XV15 a lot more than I thought I would, but it is still a large black box at the end of the day. What the XV15 does do is make large amounts of bass for not a lot of money. In that regard the XV-15 brings it with a 15” heavy duty driver, 500 watt amplifier and solidly built ported enclosure all tuned together into a well functioning complete system. Not to mention the 5 year bumper to bumper warranty. The fact that it utilizes primarily US sourced components and assembly is icing on the cake for a person like me who cares about such things. Apparently $799 can buy an astonishing amount of performance in the subwoofer kingdom these days.

The Power Sound XV15 easily meets the required output thresholds to receive the Audioholics Bassaholic Large Room rating, but was just a little short of making the more difficult Extreme room rating. It would have been the least expensive unit to do so by far. The Large room rating indicates that this sub is recommended as maintaining adequate headroom in rooms or spaces of between 3,000 to 5,000 cubic feet and/or for users who usually listen at moderate to high volume levels. For further information in how we make these recommendations see the full article here.

See: Audioholics Subwoofer Room Size Rating Protocol

Power Sound Audio XV15 Review

Power Sound Audio
sales@powersoundaudio.com
Phone: (330)349-0943
MSRP: $799 (Shipping Included)

The Score Card

The scoring below is based on each piece of equipment doing the duty it is designed for. The numbers are weighed heavily with respect to the individual cost of each unit, thus giving a rating roughly equal to:

Performance × Price Factor/Value = Rating

Audioholics.com note: The ratings indicated below are based on subjective listening and objective testing of the product in question. The rating scale is based on performance/value ratio. If you notice better performing products in future reviews that have lower numbers in certain areas, be aware that the value factor is most likely the culprit. Other Audioholics reviewers may rate products solely based on performance, and each reviewer has his/her own system for ratings.

Audioholics Rating Scale

• — Excellent
• — Very Good
• — Good
• — Fair
• — Poor

Metric	Rating
Bass Extension
Bass Accuracy
Build Quality
Fit and Finish
Ergonomics & Usability
Features
Dynamic Range
Performance
Value