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Open Box QSC KS118 3,600W 18" Powered Subwoofer Level 2 197881369255
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KS Series Active Subwoofers – Bass Your Way!

Tech Talk- KS118 Overview

Tech Talk- Keeping Bass in its place: KS Series Cardioid Subwoofer Solutions

Description
The QSC KS118 18 active subwoofer delivers uncompromising low-end power and precision for live sound environments. Powered by a 3,600W Class-D amplifier, this subwoofer is equipped with an 18" direct-radiating woofer that produces deep, chest-pounding bass down to 35Hz. Designed to handle high power and long excursion, the KS118 maintains tight, controlled performance even at high SPLs. Onboard DSP ensures advanced optimization and protection, while the DEEP mode takes low-frequency response to new depths. Whether you're enhancing a full-range speaker system or building a cardioid array, the KS118's robust engineering and innovative features make it a cornerstone for demanding live sound applications.
QSC Active Sub With Powerful 18" Driver for Deep Bass
At the heart of the KS118 is its 18" direct-radiating woofer, engineered for impactful low-end reproduction. This driver handles the high power and long excursion needed to produce bass frequencies as low as 35Hz, ensuring tight and controlled output without distortion. Paired with a 3,600W Class-D amplifier, the KS118 delivers consistent performance even in large venues. Whether used for music or speech reinforcement, the subwoofer's design ensures clear and authoritative low end, making it a reliable solution for live sound professionals seeking precision and power.
Advanced DSP for System Optimization
The KS118's onboard DSP provides advanced tools for optimizing system performance and protection. Users can configure two units in a cardioid setup to focus low-end projection toward the audience while minimizing unwanted energy behind the system. The DSP also monitors temperature, excursion, and voltage levels, ensuring the subwoofer remains protected under demanding conditions. These capabilities allow the KS118 to deliver precise bass response and reliable performance, even during extended operation in challenging live sound environments. This intelligent design ensures your system performs consistently and efficiently, regardless of venue size or acoustics.
DEEP Mode for Enhanced Low Frequencies
For bass-heavy genres and applications requiring intensified low-frequency response, the KS118 features a DEEP mode that reallocates amplifier power to deliver deeper, more impactful bass. This mode enhances the subwoofer's ability to reproduce the lowest frequencies with increased punch and rumble, ideal for modern electronic music or high-energy performances. Activating DEEP mode transforms the KS118 into a powerhouse for situations where maximum bass extension and intensity are required. With this feature, the KS118 provides unmatched flexibility for achieving powerful and dynamic low end.
Durable Speaker Build for Road-Ready Reliability
The KS118 is built to withstand the rigors of live sound environments, featuring a birch cabinet, steel grille and robust hardware. Despite its high-performance capabilities, the subwoofer remains portable, with ergonomic handles and integrated casters that simplify transportation. Weighing in at 104 lb., the KS118 is manageable for its size, making it an excellent choice for touring professionals. Additionally, the standard M20 pole mount allows easy integration with full-range loudspeakers for a complete system. The durable construction ensures the KS118 remains reliable and functional throughout demanding road use.
Subwoofers Ideal for Live Sound Professionals
The QSC KS118 18 active subwoofer offers unmatched power, precision, and portability for live sound professionals who demand reliable low end performance. Its advanced DSP, DEEP mode and robust build make it the perfect addition to high-powered sound systems for concerts, events, and installations. Whether you need impactful bass for a cardioid array or a full-range setup, the KS118 provides the tools and technology to meet your needs. Invest in the KS118 and bring thunderous bass to every performance.



Features
- 3,600W Class-D amplifier delivers massive low-end power for any venue
- 18-inch woofer provides deep tight bass down to 35Hz
- Onboard DSP optimizes performance and ensures system protection
- DEEP mode intensifies low-frequency response for chest-pounding bass
- Cardioid setup reduces rear energy and improves front projection
- Lightweight birch cabinet designed for durability and road use
- Ergonomic handles and casters allow easy transport and setup
- M20 pole mount enables seamless integration with full-range speakers
Specs
- Active/passive: Active
- Type: Direct-radiating subwoofer
- LF driver: 18"
- MF driver: Not applicable
- HF driver: Not applicable
- Amplifier class: Class-D
- Wattage: 3,600W peak
- Mixer/preamp: Not applicable
- Frequency response: 35Hz–111kHz
- Coverage pattern: Omnidirectional
- Max SPL: 136dB
- XLR: 2
- XLR: 2
- Cabinet material: 18 mm birch plywood
- Width: 20.5"
- Height: 25.2"
- Depth: 30.9"
- Weight: 104 lb.
Reviews
4.65
51 Reviews
90%
of respondents would recommend this to a friend
Most Liked Positive Review
Best pro audio sub in class without a doubt!
I've been DJing for 17 years, I've heard Vegas, EVs, JBLs, Yorkvilles, and many other pro audio subwoofers. These QSC KS118 have a very similar sound to the JBL 718 subwoofers, they go down to about 30hz and they hit you right in the chest and gut. One of the biggest differences is the distance that these bad boys are able to throw sound. My KW181s and JBLs would fall off about half court in a gymnasium, but from what I can tell these throw at least 50-100 yards and possibly further. Very clean and precise sound, tight punch and plays the extended low frequencies smoothly with no distortion. Last time I was this impressed with a subwoofer was when I heard the Yorkville LS 800p. I would say these are actually louder than the Yorkvilles and also go lower. If you're in the market for a new subwoofer, these are worth the money and will outperform anything in their price range. I'm running 4 of them and I feel as if each sub has the output of 2 KW181s.
Most Liked Negative Review
Great sub- when it works…
The KS118 is a great sub- when it's working. Lots of power and great sound. Had no problems after using it only a few times a month for a couple of months, and then without warning, sub stopped working mid show. Wasn't being pushed hard at all. Maybe running at the most at 12 o'clock. No limiter light ever came on, no warning messages, just flat out died. Not the usual QSC quality. I was surprised. I figured no problem with 6 year warranty. Took it in to a service center and now 6 months later, they tell me QSC has yet to ship them a replacement amp. Still waiting for it to get back into service. At least the warranty is going to fix it, but when is anyone's guess. QSC has new units available, but can't fix existing units- which is strange considering they use the same parts. So if you purchase one- make sure you have a backup sub as you maybe without one- for going on 6 months like mine. If yours works, you'll be very happy with the sub. Casters rattle a lot- way more that the KW181.
- Pro Audio / DJ / Mixing31
- Outdoor Events / Games30
- Performances29
- Home Studio6
- Amateur Recording2
- Bulky/Heavy18
- Pricey / Poor Value5
- Not Durable2
- Poor Sound Quality2
- Unreliable2
- Experienced29
- Professional Musician16
- Novice4
- Good Audio45
- Easy To Use35
- Durable33
- Compact21
- Versatile21
Reviewed by 51 customers
KS118s are Game changing!!
submitteda month ago
byCorey
fromMukwonago Wi
Submitted as part of a sweepstakes
For our Band, Bootjack Road. From local bars to larger outside events. We went from the KS212, which are great for their sz! To adding the KS118s for more low end Bass. And wow, way more low end!! I still like the KS212 and plan on running two 212s stacked and the then two 118s stacked and set up as Cardiod for the smaller venues. The 118s are smaller than other subs I have used, and a bit on the heavy side. So a good compromise. We just did and out side event in the middle of nothing but farm field and woods. Lat year I was pushing our old subs and they were on the verge of over heating and I was not at a volume I wanted to be. This year I barely had the system turned up and it was hitting great and oh the sound!!!
Great for indoors or small spaces
submitteda month ago
byRamiro
fromHouston,TX
Bought them for an outdoor event and the quality was bad was not enough. They would buzz when the volume was turned louder. Did not sounds good at all
This product is one of the best. I could use 4 more.
Verified Buyer
submitted6 months ago
byJohn
fromPhoenix AZ
Submitted as part of a sweepstakes
Small, compact with a big punch. I would like to have several of these as well as more powered loud speakers.
Yes
Verified Buyer
submitted10 months ago
byJuan
fromAddison il
Submitted as part of a sweepstakes
Live band
Great product and professional price
Verified Buyer
submitteda year ago
byGerardo
fromSan Diego ca
Submitted as part of a sweepstakes
Best sub on the market. Loud, clean , effective bass. No distortion.
Sounds Great, Don't Buy
submitteda year ago
byJared
fromKnoxville, TN
Used my QSC KS118 3 times. Sounded unbelievably good until today. Plugged it up and got no sound. Tried everything. For this kind of price tag, this level of quality control is unacceptable. I really wish I would've listened to all of the reviews on it.. you would think by now that QSC would've recalled all of the defective units. Thankfully, guitar center was able to honor their return policy and I was able to get a full refund. This has really put a bad taste in my mouth for QSC stuff. Not sure I'll ever buy or recommend them again. Sucks because it sounded phenomenal while it worked....
Q&A
Have a question about this product? Our expert Gear Advisers have the answers.
submitted3 years ago
asked byTim
fromFrisco, TX
What is the continuous power rating for the KS118 3600W 18" powered subwoofer? The peak is Wattage: 3,600W peak Continuous wattage is ?
Continuous wattage is:::::1260 Watts RMSsubmitted4 years ago
asked byRoberto
fromTX
where can i replace the motherboard of my QSC KS118 3,600w subwoofer
Please contact QSC.submitted4 years ago
asked byLuai
fromIndiana
I wonder if the QSC KS118 is in stock?
Please give us a call for product availability 877-687-5403submitted6 years ago
asked byThe Man
fromVA
What is the rms power for the QSC KS118
This powered subwoofer is 1000 watts RMS.submitted6 years ago
asked byMaggie
fromLehighton pa 18235
Does this QSC ks181 come with a speaker pole
This powered sub woofer does not come with a speaker pole.submitted6 years ago
asked byJason
fromCA
How do i feel out N. App.cor credit online
You can fill it out here: https://www.guitarcenter.com/Special-Financing-Offers.gc As well as read up about it further.submitted6 years ago
asked byClement
fromChicago, IL.
What's the weight (How many pounds). KS118 subwooffer.
This sub woofer weighs approximately 118 lbs.submitted6 years ago
asked byBonfire
fromWindsor ct
Weight
This sub woofer weighs approximately 118 lbs.














