Velodyne SC-IW In-Wall Subwoofer System Review

Introduction

Today’s modern interiors and trendy designs are minimalist and unobtrusive. Décor, furniture and accessories are kept sleek and small with the focus on the room as a whole. Open interior designs are meant to flow and show off the expansiveness of the entire living area. Incorporation of high- end multi-media systems into the modern interior design often leads designers and home owners toward in-wall/in-ceiling based speaker systems for home theater. In-wall based speaker systems, although aesthetically pleasing have not been recognized for their performance attributes. Manufacturers have been working very hard to overcome the limitations of in-wall speaker systems and have recently made great strides in performance. Anyone that has experienced a decent multi-channel home theater system recognizes the importance of the subwoofer for reproducing the LFE channel; but, how do you incorporate a huge box subwoofer into a minimalist interior design? Well, the short answer is you don’t; unless you deviate from the overall design plan. In-wall subwoofers are a relatively new alternative that fit nicely into the minimalist interior design. However, due the installation criteria, we haven’t heard one that truly offered high end multi-channel performance. When we heard that Velodyne introduced a new in-wall subwoofer we were curious to see if this highly regarded subwoofer manufacturer could solve the performance deficiency problems associated with most in-wall subwoofers.

Description

Velodyne’s SC-IW in-wall subwoofer is a radical departure from previous in-wall subwoofer designs. The unique 2-piece sealed enclosure design fits flush in a typical 2x4-16-inch on center studded wall. The subwoofer’s high excursion (1-inch peak X-max) T shaped driver fires vertically and the manufacturer claims performance characteristics rivaling 10-inch high end free standing woofers. Once installed and wired, the woofer enclosure is covered with sheetrock. Only the small unobtrusive grill reveals its location. The SC-IW is a passive subwoofer requiring separate amplification and for this purpose Velodyne has the optional SC-1250 amplifier. The rack mountable amplifier features 3000 watts of dynamic power/ 1250 watts RMS. Other features include sophisticated DSP control, built in test tone generator, 7-band automatic room equalizer, 12-volt trigger, IR repeater jack, RS-232 port for remote systems, and pre-programmed remote control. The amplifier can easily power two of the SC-IW subwoofers.

Configuration and Installation Considerations

Taking my room dimensions and floor plan into consideration and after receiving some very informative consultation from Velodyne, I decided to order two SC-IW subwoofers and one SC-1250 amplifier. My family room is not an uncommon layout but as described later in the review, it did pose some unexpected installation concerns. The size is about average with dimensions in feet of 12 wide x 24 long x 9 high or about 2592 CU^3. The primary listening position is about 12 feet back from the front wall. The front right side of the room is open to an adjacent room and the back of the room has a large floor to ceiling fireplace. My initial plan was to install the SC-IW subwoofers approximately 1/3-rd in from the sidewalls on the front wall. I currently have a Velodyne HGS-15X installed on the front wall about 1/3 in from the sidewall and have found this location to be optimal in my room for smooth low frequency performance.

Installing the SC-IW subwoofers in a new construction home after completion of framing and rough electrical is so easy even a Neanderthal could do it! Simply pick a suitable location, install the enclosure, pre-wire, finish and you’re done. Retro custom installations, homes that are already built, require meticulous planning and a high degree of installation knowledge. Pre-built homes can have hidden obstacles lurking in the wall, unraveling even the most thorough detailed plan provided by a professional custom installer. The bottom line with retro construction installations is if you don’t know what you are doing, leave it to a professional. The work can be daunting and even dangerous as you will find out in the next segment of this review.

SC-IW Installation Retro

If you decide you are going to proceed with a retro type installation, you are going to need some basic tools to perform the installation. You will need: stud sensor (preferably one that also detects electrical), tape measure, level, straight edge, utility knife, dry-wall saw, corded or cordless drill, wood boring bits, wet vac and other assorted hand tools. The use of a Roto Zip is optional for cutting dry wall. If you choose to finish the sheetrock patches you will also need dry walling tools. The first step is to find the location of the studs in the wall for the proposed location of the subwoofer. Remember when I told you that even well prepared plans can quickly unravel in retro-fit type installations? This is exactly what occurred with my installation. When I marked out my stud framing using my stud sensor, I discovered on the left side of the front wall the 2x4 stud framing was installed 13-inches on center and the right side of the wall framing was 16-inches on center.

The reason for the extra stud framing on the left side became clear after looking in the attic and the back of the wall. The wall is partially load bearing and has a stair case that runs along the back of the wall. This framing technique is not as uncommon as one would think. Over the many years I have been installing home theater systems, I have discovered many different configuration and variants of framing in older and even newer homes. Obviously the SC-IW subwoofer will not fit into a stud cavity of 13-inches, so I had to come up with an alternate plan. Using my stud sensor, I mapped out several alternate locations with stud bays of 16-inches on center that would accommodate the SC-IW subwoofer. Not knowing how the subwoofer would perform in the alternate locations, I decided to conduct an SPL level test at different frequencies with the subwoofer freestanding in the proposed newly mapped out locations.

At the conclusion of the test, I found that installing the second subwoofer on the left wall at the rear of the room close to the listening position provided a fairly smooth response with little compromise in localization and SPL level gain. The installation instructions provided with the Velodyne SC-IW are very easy to follow and cover all aspects of installation for new and retro-fit installations. Once the stud centers have been located, its time to use the supplied template and decide on the grill type. The SC-IW has two grill options: standard grill provides easy servicing of the driver but is a large square grill. The Designer grill is the smallest grill available and is very aesthetically pleasing. The installation method is about the same for both grill types, I decided use the small designer grill.

Securing the template to the wall and making sure it was level I marked out the appropriate pattern for the designer grill. Using a straight edge you can score the drywall with a utility knife for removal. Another option is to use a Roto Zip which is much faster. If you use a RotoZip the use of a wet vac followed closely behind the running bit will minimize dust. This is a little tricky to do if you don’t have RotoZip experience so you may need a helper. When I removed the 5/8-inch sheet rock that I cut out for the subwoofer, I was in for another little surprise. The older less sophisticated stud/electrical sensor that I was using did not sense the 1/2-inch electrical conduit installed in the stud bay. This was yet another unexpected retro installation hurdle to over come but this did provide me with an excuse to purchase a newer more sophisticated sensor like the Ryobi that will detect electrical as well as metal. I got lucky and this was a relatively easy fix because the conduit was installed in the lower half of the stud bay. If the conduit had been installed up higher I would have needed to patch the wall and find yet another alternate location. The simple fix was to move the SC-IW subwoofers location up two inches and patch the bottom of the wall.

Once the sheetrock is cut out, it should be relatively easy to pre-wire to the subwoofer. The size of the cut out should provide you with plenty of room to drill trough any blocking installed in the wall. The SC-IW installation manual shows a picture of generic non in-wall approved speaker wire installed in the stud bay. Do not use speaker wire like the one pictured in the installation manual. All wire that is to be installed in the wall should be rated for in wall installation and comply with the National Electrical Code (NEC). Speaker wire approved for in wall installation will typically be stamped with the designation UL approved CL2 or CL3. I used 16-4 (13 AWG equivalence) in-wall wire with the four conductors doubled up to make one twisted pair to each subwoofer. The use of good 12-2 in-wall wire will work also. The wire should be attached to the side of the stud bay so it won’t interfere with the enclosure installation. Installing the enclosure is fairly straight forward: simply terminate the speaker wire and screw the enclosure into the studs with the provided screws. I marked the location of the oblong holes on the SC-IW installation brackets to provide a location to screw through the dry wall into the stud missing the metal bracket. Once the enclosure is installed its time to install the new sheetrock, filler panel and grill insert. Make sure to secure the existing sheetrock to the studs before finishing. Now that the rough sheet rock patch is installed, you can finish the dry wall patch. I chose to do my own drywall patching and texture work but you may choose to hire a pro depending on your skill level. One problem I discovered after the drywall compound dried was the filler panel shipped with the SC-IW is very smooth and my first patch attempt did not adhere to it after curing. This is partially my fault as I should have noticed this before doing my dry wall compound patching work.

Removing the installed filler panel, I used 60 grit sand paper and acetone to roughen up the filler panel surface. This provided the grip needed for the dry wall compound to adhere to the surface. With a wide dry wall mud knife I applied a rough and finish coat of quick set dry wall patching compound insuring each coat was dry before applying the next. Once the finish coat was complete and dry, I proceeded to sand the patch until it was smooth and blended in with the existing wall. I used canned spray texture to spray the texture coat finish onto the wall. This is available at most home improvement stores and with a little patience and practice you can achieve really great results. Installing the metal grill and painting the drywall patch is the last step in the installation process. The designer grills are paintable; you may choose to paint them the same color as your wall for a blended appearance. I took a different approach and decided to highlight the grill with gloss black paint to complement the rest of the black components in my system.

SC-IW Setup, Measurments and Analysis

The SC-1250 amplifier is extremely connection flexible and can be configured for just about any type of installation. The most common approach would be to use your receiver’s LFE subwoofer pre-output jack and connect it to the SC-1250’s LFE input. If your receiver or processor handles the entire subwoofer crossover duties you can disable the SC-1250's low-pass crossover to prevent cross over cascading. In my multi-channel system, a subwoofer LFE cross over setting of 60-Hz worked best and is the setting I used on my receiver setup for this review. The SC-1250 amplifier can control and power a variety of different subwoofers. The amplifier needs to be programmed for the specific type of subwoofer installation; this is achieved by powering up the amplifier while pressing any of the buttons on the front panel. After the amplifier boots up you can choose SC-in-wall (IW), SC-in-floor (IF), SC-in-ceiling (IC) or Generic Subwoofer (GS). Since this is an in-wall subwoofer the selection of the (IW) setting is the correct choice. Calibration is very easy thanks to the remote included with the SC-1250 amplifier. I calibrated the SC-IW subwoofers SPL to match the level of the speakers in my system using my trusty Radio Shack SPL meter. The amplifier has an adjustable phase setting of 0-90-180 and 270. The proper setting for the phase would be the setting in which you hear or measure the most even bass at your listening position. Unfortunately the phase setting is not independent for the two subwoofers and is applied to both “A” and “B” subwoofer output speaker terminals on the SC-1250 amplifier. I wanted to measure the response of the subwoofers with the two subwoofers out of phase. I mechanically reversed the phase of one of the SC-IW subwoofers at the amplifier’s subwoofer speaker terminal. Reversing the phase effectively placed one of the SC-IW subwoofers 180 degrees out of phase. After going through the multitude of phase settings with both subwoofers’ wire in phase and out of phase, I found the best setting for the room to be both subwoofers wired in phase and the amplifier phase setting at 0. Connecting the small supplied omni-directional microphone and pressing EQ on the remote enables the Automatic EQ program. The amplifier/subwoofer emits 12 “Sweep Tones” from 20-150Hz. After the amplifier completes and processes the measured information, the amplifier returns to normal operation and is now configured for your room. The SC-1250 has four preset EQ settings, for reference level the Jazz/Classical level applies no EQ or Volume Differential.

Preset	Filter Frequency	EQ Frequency	EQ Level	Volume Differential
Movies	24 Hz	37 Hz	+4 dB	+8dB
R&B Rock	27Hz	52Hz	+3dB	+5dB
Jazz/Classical (Reference Level)	24Hz	N/A	N/A	N/A
Games	34Hz	62Hz	+4dB	+4dB

Measurements & Analysis

In-room measuring conducted at the listening position should not be considered a good indicator of how well the subwoofer system will perform in your room and should be used as a reference only. Just keep in mind that subwoofers will perform differently due to room dimensions, listening position, subwoofer placement, and room acoustical properties. I used the Rives Bass and Room Evaluation (BARE) analyzer with the omni-directional microphone placed at the primary listening position, with the SC-1250 amplifier set to the Reference Level EQ setting for all recorded measurements. All of the surround sound speakers were deactivated so they wouldn’t interfere with the subwoofer measurements. The Rives BARE system is fairly basic, giving me only two frequency response graphs to work with (5-50Hz and 5-500Hz) I decided to measure the response using both for a more accurate representation of how the subwoofers measured.

The first measurement taken 5-50 Hz, to my surprise measured fairly flat from about 18Hz-50Hz. As you can see the response dropped off rapidly at about 16Hz. Considering the SC-IW has an advertised low frequency cut off of about 22Hz I would say these subwoofers actually exceeded the manufacturers low frequency specification in my room. The second measurement of 5-500Hz shows a very similar response from 5-50Hz, a 10dB dip at 55Hz and then a gradual roll off at 60Hz. This is exactly what I expected as the receiver’s internal x-over is set for 60Hz. The dip at 55Hz is a characteristic of the room, as this room has absolutely no acoustical treatment in it at this time. Considering the less than perfect room conditions and the subwoofer placement issues I had to deal with, I was quite surprised to see the relatively good frequency response measurements.

SC-IW Listening Tests

Listening Evaluation Movies

I decided to use the older not particularly great movie DVD: Dare Devil (Directors Cut). I selected this movie because it has a terrific DTS soundtrack, excellent music score and phenomenal low frequency. Beginning with chapter four “The Accident, Matt arrives just in time to see his dad strong arm a gambler for a loan shark in the alley. Confused and dismayed Matt drop his straight “A” report card in the puddle of water and runs away. As Matt runs away there are several low frequency bass drum beats, the SC-IW subwoofers reproduced this subtle low frequency effect with a very high degree of accuracy. This is a very important part of the music/effects passage that leads up to the chaotic accident and is designed to prepare the viewer for an important event and sets the tone of desperation for the movie. I have heard this series of low frequency effects many times with several different subwoofers. A very good subwoofer should reproduce the deep pounding of the drum with authority and the bass beats as they occur should decay quickly. I listened to this part of the chapter over and over again; the SC-IW consistently reproduced the low frequency effect and music score leading up to the accident perfectly. The consistent beats of the drum sounded tight and the notes decayed as they should with no over hang, lag or unwanted rumble. I was fairy surprised to hear such accuracy, considering the subwoofer is installed in the wall. When I first installed the woofers, I had the assumption that I would hear some boom, exaggeration and overhang because this is what I have experienced with in-wall low frequency transducers in the past.

Pleasantly surprised, I progressed through the chapter until Matt reaches the accident scene. As he is running though the work yard, the LFE soundtrack really comes alive and so did the Velodyne SC-IW subwoofers. As the fork lift hits the drum filled with radio active material, my whole room began to shake with the constant rumble of low frequency bass as Matt’s life is changed forever. In the next sequence of events, the scene and the soundtrack change abruptly into what I can only describe as a hallucinogenic mind trip. Suddenly, Matt awakes in the hospital bed gasping for air unsure of his circumstances. As this occurs and as he rapidly rises out of the hospital bed, there is wave after wave of subsonic chest pounding bass, a recreation of his newly acquired super human hearing. Every little sound is amplified to bone crushing level. This short but powerful part of the soundtrack can kill all but the mightiest subwoofers when played at reference levels. Many times I have heard the awful “Clack” sound as the woofer bottoms out trying to reproduce this wave of bass. It takes a very capable subwoofer to effectively reproduce the violent howitzer cannon like bass effect and the SC-IW didn’t disappoint. As I sat listening, my body feeling the tremendous pounds of the LFE, the first thought that came into my mind was that I was listening to a very good stand alone box style subwoofer. Accuracy, pitch, and definition as reproduced by the Velodyne in-wall subwoofers were exactly what you would expect from a good mid sized subwoofer that is not installed in a wall. Yes, you read it correctly! I turned the volume up on my Yamaha RX-V4600 receiver and the SC-IW subwoofers blasted out the loud low frequency bass along with the sounds of the city and hospital contained in the soundtrack. The two Velodyne subwoofers filled my room with tremendous amounts of clean bass.

However, when I pushed these subwoofers to levels that you would only hear in military combat, they started to sound a little aggressive and less composed. This is to be expected given the size of the woofer contained in the SC-IW .My recommendation would be to install two SC-IW subwoofers in larger rooms. The rhythm, accuracy, definition and SPL slam that two subwoofers produced in my medium sized room at higher than modest listening levels was on par with many free standing 10-12-inch box subwoofers and in some instances the SC-IW subwoofers exceeded the performance of their boxy brethren. Immediately after the somewhat lengthy low frequency medley concluded, I hesitantly placed my hand on the top cover of Velodyne SC-1250 amplifier. Surprisingly the amplifier was just barley warm to the touch. This is important because it ensures the SC-1250 amplifier shouldn’t have any trouble installed in a closed equipment rack with adequate ventilation and proper component spacing.

Listening Evaluation Music

I have often wondered why some of the most beautiful voices and talented music artists are not used for music evaluation. As self proclaimed audiophiles and videophiles, we seem to have a strong bias about what type of music should and shouldn’t be used for equipment evaluation and demonstrations. Yet we continually pass over some of the most talented performers in the music industry to maintain our sometimes bloated audiophile credentials. I must admit that I am just as guilty, using only what I believe to be reference material and thinking it must meet a strict standard for my readers. Today’s modern country music performers are just as popular and in some cases more talented than yesteryear’s rock stars. The yodelling and twang that permeated the air waves in the 50’s, 60’s and 70’s is now pretty much a thing of the past. Modern big billboard county music singers and bands debunk the typical bumpkin stereo type tag that is often placed on them. Brooks & Dunn, a band that has been filling sold out arenas for about the last two decades, is what I would characterize as two fun loving country guys surrounded by a rock band. Their music can be fun and fast paced or slow and thought provoking.

I began the listening evaluation with CD Brooks & Dunn, The Greatest Hits Collection II This CD is wonderfully recorded to audiophile reference levels and the music contained in the CD is just awesome. Track 3, “Ain’t Nothing ‘Bout You”, starts out rather quickly with an electric guitar, fast mid bass drum beats followed by an electric steel guitar with bass guitar mixed in. Breaking down the first part of the song from a technical stand point, the subwoofer in the system must be able to reproduce two different bass instruments at different frequencies at the same time. The drum and the bass guitar in the first part of the passage are recorded at roughly the same reference level. High performance subwoofers should be capable of reproducing the notes of both instruments so that one doesn’t dominate over the other. In other words you should be able to hear the drum and bass guitar clearly producing the notes at the same time. I have listened to this opening passage with subwoofers that were not capable of reproducing the instruments accurately.

Editorial Note on Speed and Accuracy of Subwoofers

What’s heard is a blurring of the drum and the bass guitar with the drum dominating and the bass guitar muted. This occurs because the subwoofer can’t maintain a high degree of accuracy. This, in technically not accurate audiophile speak can also be referred to as the speed of the subwoofer. Throughout my years as an installer, I have often found that high end sealed subwoofer designs, when designed correctly, are very accurate. This is not a blanket statement about subwoofer design in general because advanced engineering and software have improved other subwoofer designs significantly. It may just be my own personal bias but I never grew attached to subwoofer designs that have the driver firing down toward the floor. The subwoofers that have drivers firing toward the floor seemed to do a fine job filing the room with generous amounts of tactile response, but in my opinion they always sounded sloppy and in-accurate for highly technical music passages. The SC-IW subwoofer is a sealed design, but the driver when installed in the wall either fires up or down. Try as I might during the installation of the subwoofers I couldn’t set aside my bias that a good music subwoofer needs to mechanically point out into the room.

As I started listening to the music, I quickly realized that the SC-IW subwoofer shouldn’t be lumped into the downward firing subwoofers that I have heard in the past. Proceeding through the evaluation, the drum and the bass guitar notes were distinct, nicely separated, and heard with relative ease when being reproduced by the in-wall subwoofers. The Velodyne subwoofers integrated beautifully with the rest of the speakers I had in my system. Bass transitions were very smooth and there were no notable gap’s in the lower frequency response. I did however detect a very slight amount of exaggerated over emphasized bass from the bass guitar as the song progressed. For comparison, I have one of the most accurate subwoofers on the planet, the mighty HGS-15X, also manufactured by Velodyne. Don’t let the age fool you, having had many high end subwoofers in my system, I can tell you the HGS-15X is the George Foreman of subwoofers. Continuing the comparison evaluation with the HGS-15X, I did hear some performance differences, most notably the way the instruments interacted with each other. The differences were not night and day between the two different subwoofers but they were there. The HGX-15X produced the bass notes from the instruments with the same degree of authority but decay time between the notes happened much quicker with no overhang or exaggeration. Overall the bass presentation with the HGS-15X was much smoother and more refined. I believe the interaction and coupling between the SC-IW’s enclosure and the wall surface to be the contributing factor. I am not entirely sure it’s fair to compare one of the best sealed subwoofers ever built to an in-wall subwoofer. However, if you are a very picky audiophile primarily listening to complex music passages perhaps you should consider a high end free standing subwoofer. The two SC-IW in-wall subwoofers did a very good job in my room with music; I would say the performance level of the subwoofers rivalled very good 10-inch sealed stand alone subwoofers. If your music tastes are geared more towards Country, Rock, Jazz, R&B, Hip Hop or Rap you will really like what you hear from the Velodyne in-wall subwoofers.

SC-IW Conclusion

As designers and their design philosophies continue the path of less is more, engineering audio products that conform to the minimalist profile without performance sacrifice can be virtually impossible. No where is this truer than with subwoofers. Here is the concept: Take a large freestanding box subwoofer, shrink it down to fit in a 2x4 wall and still maintain high performance levels, Yeah I wouldn’t have believed it either. Yet, this is exactly what Velodyne has accomplished. The Velodyne SC-IW in-wall subwoofer rivals the performance of many very good 10-12-inch freestanding box subwoofers. Once installed, the only tell tale sign that you have a subwoofer in your room is the small unobtrusive grill. If your plan is to build a high end home theater system with little compromise in performance and minimalist design cues, this is your subwoofer. The SC-IW installation process is fairly straight forward, but if you have an older home it can present some interesting challenges. Careful planning, placement, and caution must be adhered to during the installation process.

Overall, the SC-IW subwoofers performed well beyond my expectations and erased any preconceived notion that I had about in-wall subwoofers. The SC-1250 amplifier is a sophisticated power monster that provided flexible connectivity and very good room equalization software. The SC-IW is not without faults as outlined in the music evaluation part of the review, but this is rather trivial considering this is an in-wall subwoofer system. In my modest sized room, two of the SC-IW subwoofers in conjunction with the SC-1250 amplifier achieved incredible performance levels with all but the most sophisticated soundtracks. Needless to say the Velodyne SC-IW is the best in-wall subwoofer system I have heard or installed to date. I highly recommend the SC-IW subwoofer and SC-1250 amplifier to home owners, custom installers, and designers that wish to maintain the minimalist design trend without performance sacrifice. –Bravo Velodyne!

345 Digital Drive
Morgan Hill, CA 95037
Tel: (408) 465-2800
Fax: (408) 779-9227
www.velodyne.com

Company Overview

Velodyne Acoustics, Inc., founded in 1983, is universally recognized as the leading manufacturer of high-performance, low distortion powered subwoofers at all price levels. Headquartered in Silicon Valley, California, the company's technically innovative audio products are available through a select group of authorized dealers, custom installers, and distributors worldwide.

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
Ergonomics & Usability
Features
Performance
Value