SVS 13-Ultra Amplifier Upgrade Kit

SVS 13-Ultra Amplifier Upgrade Kit

53 reviews
Available for all SVS 13-Ultra Series subwoofers, the 13-Ultra Amplifier Upgrade Kit unlocks all the world-class technology, advanced DSP controls and innovative features available in the acclaimed 4000 Series Sledge 1200D amplifier platform, including:
  • SVS Subwoofer DSP and control smartphone app
  • 1,200 watts RMS, 4,000+ watts Peak power amplifier with fully discrete MOSFET output
  • 50Mhz High Resolution Analog Devices Audio DSP
  • Active Power Factor Correction (PFC) and ground loop isolation

SVS 13-Ultra Amplifier Upgrade Kit

45 Day Risk-Free In-Home Trial

$ 399.99


Select the amplifier that matches your 13-Ultra subwoofer.

SVS 13-Ultra Amplifier Upgrade Kit

Product Overview

Upgrading SVS 13-Ultra Series to the Most Advanced Amplifier Platform Available.

13-Ultra Series subwoofers are among the most successful SVS models of all-time and established SVS as the top subwoofer manufacturer worldwide. If you own a 13-Ultra subwoofer and are curious about how the SVS subwoofer control and DSP smartphone app can help in-room optimization, or just want to push the limits of performance even further, the 1200D Amplifier Upgrade Kit is an affordable, easy-to-install option.

Amplifier Specs:

  • Massively powerful Sledge 1,200-watt continuous Class D design with 4,000+ watts of Peak Power.
  • Unmatched intelligence from user adjustable low pass, phase, polarity and room gain compensation with three parametric EQs and port tuning (Ported models only) for absolute best alignment with speakers and optimized performance in any room.
  • Groundbreaking SVS Bluetooth DSP control app for iOS and Android devices with three user presets allow custom tuning for every room and system.
  • High efficiency cool-running Class D switching topology with massive 32 Amp 600 Volt MOSFET’s result in lower EMI and highest efficiency while providing effortless power to produce SPLs and low frequency output with pristine clarity well beyond reference listening levels.
  • High resolution 50Mhz Analog Devices Audio DSP with double precision 56bit filtering is most advanced subwoofer processor available for perfect audio reproduction.
  • 100v-240v full range input active Power Factor Correction (PFC) pre-regulates mains to solid 360V DC regardless of mains voltage or quality so the sound quality never falters no matter what’s coming out of the wall
  • Active PFC lowers average current and smooths mains input current allowing for 1200W output from a standard 15A mains circuit.
  • XLR and RCA stereo input/output with ultra-wide input voltage for consumer and professional audio applications.
  • Auto/On and 3-30V AC/DC trigger for Maximum Installation Convenience.
  • Input impedance 22kohm (unbalanced RCA)/ 22kohm (balanced XLR).
  • Green 0.5-watt low standby power consumption
  • RoHS compliant, lead-free construction, world-wide safety certifications

SVS App Specs:

  • The most powerful and flexible Bluetooth controlled subwoofer DSP app, works with both iOS and Android operating systems.
  • Easiest and most convenient way to adjust crossover frequencies, parametric EQ, polarity, room gain and all other bass management functions.
  • Three convenient custom presets allow for perfect tuning in any room or system, from your favorite seat.
  • Single tap adjustment for controlling variable port tuning with standard, extended and sealed modes.
  • Easy-to-follow tutorial provides clear guidance for all functions.

SVS Subwoofer DSP and Control Smartphone App

Groundbreaking SVS Subwoofer Smartphone App is the easiest way ever to manage a subwoofer’s performance. The app connects via Bluetooth with Apple iOS®, Android® and Amazon devices and will unleash the full depth, force and nuance of the 13-Ultra Series subwoofers by giving control over all DSP functions. It also features custom presets for easy one-touch adjustments based on saved preferences for movies, music or other content.

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SVS Subwoofer Smartphone App Features:


Adjust to make your system’s low end more robust and extended while remaining accurate. The subwoofer should sound like it’s naturally adding bass for all the speakers without overly drawing attention to itself. Different content has different levels of output so it’s normal to adjust volume based on source material and your personal listening preferences.

Low Pass Filter

Enables smooth sonic transition and flat frequency response between speakers and the subwoofer. If using an AV Receiver with a Subwoofer Output, leave in the OFF position. For two-channel systems using an AV processor or preamp, this allows you to control the upper frequency cut-off to blend with main speakers. It also allows you to adjust slope, or the rate at which the low pass filter rolls off.

Phase Adjustment

Solves sound wave cancellation issues at specific frequencies and perfectly aligns the arrival of output from speakers and subwoofers to your listening position. Normally set to 0° if the subwoofer is near the main speakers. Adjusting Phase shifts timing of the subwoofer output to align with the main speakers or additional subwoofers.


In some cases, reversing polarity solves dips or humps at the crossover frequency between a subwoofer and speaker and can be used to fix bass nulls or overly boomy spots in the listening area. Reversing the electrical polarity of the subwoofer amplifier makes it so the woofer moves in when speaker drivers move out and is normally set to positive

Parametric EQ

Powerful tool for removing peaks and dips in your listening area, and for creating custom subwoofer output based on listening preferences. Works best when used with acoustic measurements.

Allows you to set the desired center frequency of the filter, increase or decrease the SPL dB of the filter or adjust the bandwidth of the filter.

Room Gain Compensation

Fixes bloated sounding bass by optimizing low frequency output and extension when too much sound wave density is being created by a small room.

Port Tuning

Allows custom tuning for different listening preferences. Exchanges max output for low frequency extension and transient speed.

Since the vast majority of SVS subwoofer owners never use the port plugs and many end up in landfills, we’ve made them optional to be a bit more eco-conscious. We are happy to send port plugs free of charge if they will be used, just note in the special instructions during checkout.

Custom Presets

Allows up to three pre-saved settings for movie, music and custom. This enables easy switching to optimize your 13-Ultra subwoofer’s output and settings based on your specific listening preferences with different kinds of content.

System Settings

Allows you to make further customizations and reset your subwoofer to factory settings.

Sledge STA-1200D Amplifier – Massive Output, Sophisticated DSP, Advanced Power Management

Rated conservatively at 1,200 watts RMS, and 4,000+ watts peak power, the Sledge STA-1200D amplifier uses an efficient Class D design combined with fully discrete MOSFET output and a sophisticated Analog Devices DSP engine. The result is a level of effortless power and advanced processing not available from any other powered subwoofer manufacturer.

1,200 Watts RMS, 4,000+ Watts Peak Power with Discrete MOSFET Output

Conservatively rated at 1,200 watts RMS, 4,000+ watts peak power, the SVS Sledge STA-1200D Amplifier combines the efficiency of a Class D amplifier with the ability to move nearly limitless amounts of current through the fully discrete MOSFETs. The result, massive and effortless power with pinpoint control and accuracy at all drive levels.

Active Power Factor Correction (PFC) & Ground Loop Isolation

Serves as a line conditioner, surge suppressor and voltage regulator letting the amplifier deal with wide voltage fluctuations and ensuring the subwoofers operate flawlessly on any household circuit no matter how unstable the incoming current. An isolated circuit creates a vanishingly low noise floor by eliminating the potential for ground loop hums from outside components resulting in absolute sonic transparency.

50 MHz Analog Devices Audio DSP

The most advanced processor ever used in a consumer subwoofer, a 50 Mhz High Resolution Analog Devices Audio DSP, allows the subwoofer to blend with any speakers and maintain pristine sound quality through advanced in-room tuning, optimized frequency response curves, powerful DSP controls and more.

Sound Expert Videos

How to Reduce Subwoofer Room Rattle, Vibrations and Bass Bleed

Anatomy of an SVS Subwoofer Driver

Comparing Ported vs. Sealed Subwoofers for Home Theater

SVS 4000 Series Technology Overview

Section Shadow
Subwoofer Matching Tool

Enter your speakers and the SVS Subwoofer Matching Tool will recommend suitable subwoofer matches as well as crossover frequency and low pass filter settings.

System Builder Tool

Personal SVS speaker and subwoofer system builder. Choose from preset home theater surround sound set-ups like 5.1, or custom build your own.

User Reviews | Press Reviews

Customer Reviews
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Filter Reviews:
Maurizio P.

Fantastic Upgrade !

Fantastic Upgrade !

Haris J.

Great Amp! But removing my old amp was a Nightmare! dented old amplifier

I have been happy with SVS products and their customer service! I own NSD12, two SB2000, two SB13-Ultra, SVS Ultra towers, and SVS Ultra bookshelves. This is a great upgrade as I have more control over my subwoofer's performance and it is much better than moving the sub to adjust the controls. I can't tell the difference in power vs the old sledge amp, but what I can tell is that the bass is cleaner in my 2 channel music system. Now the bad part. The removal of the old amp for me was a total nightmare! I removed the ten screws as stated in the manual, and pulled on the amp with no luck. I tried the nail head trick and that didn't work. My old amp was stuck so hard that when I tried the nail trick it would raise the front of the subwoofer 7-8 inches and the amp still wouldn't budge! At this point the nail head trick had bent and created a 4-5mm gap between the amp and the subwoofer cabinet, so I was able to pull the amp out by wedging a flat head screwdriver in the small bent/gap and leveraging it very slowly for few minutes. Removing the wires from the old amp was super easy, however when I time came in to put the new amp I noticed that it was not sitting flush in the cabinet cutout, and this was the reason why my old amp was stuck so hard! - it was wedge inside the cutout!. I think SVS should create some screw holes in the amp plate and provide some screwable handles that can be mounted on the amp plate to pull it away from the subwoofer cabinet. I might be the only one whose amp plate was wedged in so tightly but the removal of the old amp can bent / dent it. Crossing my fingers that I dont have to replace this new amp as removing the amp was not easy in my case.

Eric H.

Ultra 13 Amp Upgrade

Easy to install with video tutorial. Up to date and easy to use features with the app. Added power from the mew amp can be felt and heard.

Hussain M.

This is soo cool

Thanks SVS for keeping the customer first. I love the upgrade. Easy to follow instructions. The iOS app is a blessing.

Donald S.

Awesome addition to my home

Awesome addition to my home theather