Dual SVS 20-39CS+ Review

I receive the UPS shipping notice and check the UPS tracking system. Delivery scheduled for Tuesday the 12th. Cool!!! Arrange to take the 12th off (I tell everyone I am getting new woofers and get many strange looks). Wake up Tuesday and start getting the equipment rack ready and run the speaker wires. 9:30AM where is the damm truck?! Get some coffee, play with dog, watch some news, get some more coffee. 10:30AM where is that damm truck?! Get some coffee, jump online, do what I can on our "work from home" system, get some more coffee, play with dog. 11:30AM where is that damm truck?! Get some coffee, play with dog, watch a movie, get a soda. 1:30PM where is that damm truck?! Get a soda, get online, check UPS status, still delivery pending. 1:45PM where is that damm truck?! Go outside, pace around, get a soda. 2:00PM where is that damm truck?! Start thinking that I have had too much caffeine. 2:10PM where is that damm truck?! Start getting paranoid "Ron and Tom are playing a cruel trick on me", "UPS hates me", "the Police have arrested the driver for stealing SVS woofers" well you get the idea. I was in pretty rough shape. Trying to calm down I put in another movie. Can't stop thinking about how much better the movie would be with more bass. 4:30PM where is that damm truck?! Get a soda, peer out windows unaware of time, hear dog barking, slowly come out of coma, realize the doorbell is ringing, open front door, greet UPS man shaking with excitement, wipe drool from face because he is looking very scared, barely hear the UPS guy "say here take this (Samson) I have two other items on the truck", manage to croak out "ok". Get everything inside, the sun comes out, music plays, the choir sings. Time is 5:30PM.

I unpack everything noting how well all the items are packed and remembering not to throw away the port plugs. I try to hook everything up, crap need some adapters, get keys, head to Radio Shack, ignore salesman asking if I need help, spend precious time trying to find adapter, salesman seeing my crazed look asks again, I tell him what I need, he points to the rack right in front of me and asks "is this what you need", I grumble "yes" (ok I think there is a lesson in there somewhere but I was too crazed to care...must get bass), stop and get some food, arrive home. Time is 7:30PM where is that damm...remember that I already have the woofers. Hook up inputs, hook up speaker wires, turn on amps, quickly turn off amps due to large hum coming from woofers, curse, tear up house looking for cheater plug, don't find cheater plug, curse, get keys, go to Home Depot, get cheater plug (I know my way around Home Depot), drive home. Time is 8:30PM. Insert cheater plugs, turn on amps, here silence, wonder why it is sunny at 8:30 at night, wonder where the music and singing is coming from. Start calibration (read below), curse, reverse wires, take measurement, yell "yippee". Time is 9:50PM. Insert Star Wars EP1, live in bliss for 10 minutes, remember what a nice neighbor I am, turn off system, go to bedroom, crash with a big smile on my face. Time is 10:10PM.

The Woofers and Powerplants:
Single 20-39CS/Samson S1000 and Dual 20-39CS+/Samson S1000

The Room Setup:
The room where all my equipment is setup has been described as "difficult" by Tom V.  It is open to the kitchen and several hallways. It also has a tall sloped ceiling. I have a diagram of it on my web page if anyone wants to see it. I live in a ranch style house built on a solid concrete slab. The floor covering is just carpet padding and carpet on top of the concrete. Again there are pictures of the room on my web site if anyone is curious. All three SVS woofers are in the same corner.

Bass Equipment Hookup:
The LFE/Subwoofer output of my Harman Kardon AVR510 is split 4 ways. It drives the 2 25W Aura Bass Shakers, the Hafler P505 amplifier, and the Samson S1000 amplifier.

All my speakers are set to small with the crossover occurring at 80Hz. The subs were calibrated using the VE subwoofer test section and the Radio Shack analog meter. My previous settings with the single 20-39CS were 76dB with a setting of 3dB on the AVR510 and the gain wide open on the Hafler. Since I am using 2 amplifiers to drive the 3 woofers I had to sit down and think for a bit. I figured that the dual 20-39CS+ combination would put out more bass then the single 20-39CS (duh) so I decided to calibrate the dual woofers first. My reasoning was that if I could get the setting on the AVR510 close to where it was for the 20-39CS with the dual woofer combination I would not have to worry about over driving the single 20-39CS. I opened up the gain all the way on the Samson and started the procedure using the VE test tone. I ended up calibrating the dual woofer package to 78dB on the RS meter. At this level the AVR510 setting was at 8dB!! I got 2dB more output while reducing the AVR510 setting by 5dB!! I then turned on the 20-39CS/Hafler combination with the dual woofer on. The overall dB on the RS meter went DOWN..ACK!!! Well shucks I was bummed. I spent some time troubleshooting and I finally reversed the phase on the 20-39CS by switching the plus and minus speaker wires at the Hafler. Tested again and BINGO adding the 20-39CS now added +3dB on the RS meter (remember that it is not being driven to reference levels due to the reduced setting on the AVR510). So my final settings using the VE test tone using all three woofers are 8dB on the AVR510 and 81dB on the RS meter.

What can I say but WOW! I had some friends over and everyone was very impressed to say the least (I think I have made some converts). Buying the first SVS took me to one level of bass (you all know that story by now) but adding the dual CS+ woofers put me in heaven. I cannot believe the sound that is coming out of these suckers. Those of you who have these beasts in smaller sealed rooms must just be drunk with bass. We watched Star Wars: EP1. The THX intro was amazing, the pod race was amazing, everything was amazing. We watched the intro on Toy Story II. Pant legs were moving and all sorts of things were rattling (time to get some blue tack). Suffice to say everything we watched was spectacular.

Another indication on how great these woofers are comes from my dog. Now my dog Java is very used to high sound levels by now and nothing bothers her. Normally she will curl up and sleep during movies. However, during these demos whenever there was a big explosion or a bunch of bass effects she would leap up on all four legs and start looking around to see why the world was ending.  That is some powerful bass!!

Awesome!! I am going to play around with port plugging next.

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Last Modified On: 07/22/2005