AT-900.1d // 1200 Watts RMS Monoblock Car Audio Amplifier

$279.99 Regular price $349.99 Sale price

You Save 20% ($70.00)


The CT Sounds AT-900.1d Monoblock Car Audio Amplifier will deliver the power you need to destroy the competition in the SPL lanes. Built using an advanced PCB board featuring Korean capacitors, MOSFET Pulse Width Modulated power supply, high-quality transformers, and cutting-edge inductors. Equipped with 4-way protection circuitry along with 2 Diode 6A60 for reverse polarity protection; sleep easy at night knowing your mono amplifier is protected.

The plexiglass backing, illuminated LED CT Sounds logo, and white chassis gives this amplifier an unbeatable appearance. Not to mention the amplifier comes with the highly sought-after AT Series On/Off Bass Knob which not only lets you adjust the bass boost but also displays your system voltage.

Whether you’re looking to cause a tectonic disturbance or generate dynamic instability in the atmosphere, the CT Sounds AT-900.1d has the power to create the sonic explosion you crave. Variable adjustment controls feature gains, subsonic, bass boost, low pass filter, and phase settings so you can get the exact sound you are looking for out of your amplifier. The car monoblock amplifier is strappable so that you can get more power output should your system require it. It even has a master/slave switch for added convenience

Quick Facts:
RMS Power: 1Ω @ 12.8v 900 Watts x 1-Channel
RMS Power: 2Ω @ 12.8v 450 Watts x 1-Channel
RMS Power: 4Ω @ 12.8v 225 Watts x 1-Channel
Power & Ground Input Size: 4 Gauge
Speaker Input Size: 8 Gauge

Technical specifications:

  1. Monoblock Class D Amplifier
  2. RMS Power at 1 Ohm: 900 Watts x 1-Channel (12.8v)
  3. RMS Power at 2 Ohm: 450 Watts x 1-Channel (12.8v)
  4. RMS Power at 4 Ohm: 225 Watts x 1-Channel (12.8v)
  5. Frequency response: 10Hz ~ 250Hz
  6. Gain adjustment: 0.2v ~ 5v
  7. Subsonic adjustment: 10Hz ~ 50Hz
  8. Phase adjustment: 0º to 180º
  9. Bass boost: 0dB ~ +18dB
  10. Signal to noise ratio: 100dB
  11. Damping factor: 180
  12. Minimum impedance: 1Ω (ohm)
  13. Low Pass filter: 35Hz to 250Hz
  14. No of fuse: 3 x 40A (each)
  15. Strappable: Master/Slave switch
  16. Bass knob: Remote gain control, clip light indicator, built in voltmeter & push-able on/off switch


  • 190mm (W) x 54.5mm (H) x 300mm (L)


  1. MOSFET PWM (Pulse Width Modulated) power supply
  2. Soft turn on circuitry
  3. 1 ohm stable mono operation
  4. Thermal, DC offset, overload and speaker short protection inbuilt
  5. Nickel plated RCAs, thus low resistance inputs to the amp
  6. LED power and protection indicators
  7. It comes with Remote Bass Knob; therefore allowing you to control power on/off or subwoofer bass level easily
  8. This is a purely Class-D amplifier where the audio amplification is solely controlled by electronic amplifying switches inside; making the gain much more effective and enthusiastic

Customer Reviews

Based on 29 reviews
Justin Vonasek
Hits hard and clean, but..

Kept blowing fuses. First off, it really does sound incredible, and easily underrated power even considering it's rated at 12.8v. It was feeding a 12" Fi ZX3 subwoofer quite well. I'm running a 240v Mechman alternator, 0/1 OFC wiring plus big 3, grounds are proper as can be, gains set properly, no bass boost, no nothing. Several times, it would be hitting great for ten minutes and blow my inline fuse. After a couple instances, it wouldn't come back on. Sent to Amp Medics, who bench tested it out all fine and well. Hooked it back up, hit good again. 15 minutes in, another fuse. And another after that before not turning back on again. I pulled the whole bass setup out for 8 months from frustration. I ended up getting a Crescendo Symphony s1v2 last weekend. Everything is as it was setup with the CT and it's been beating my car to death consistently for two hours play time so far with no issues.

Perhaps, and assumably, I received a lemon. For as clean sounding and cool running of an amplifier it is, I would probably buy another from CT in the future.

Derek Apple

Very nice quality both on design and performance

Gus Quinones

I've wanted this amp for a cpl years & finally got the chance to get it. Build quality seems really good. If it's anything like the Strato 10's I have, I know it'll be amazing. I bought 2 amp to strap with the 2 Stratos. Haven't had the chance to install them yet, but I'm not really concerned. Every CT Sounds product I've used has been amazing. CT Sounds absolutely has a customer for life. I will update as soon as the install is done.

Tracey Corn
Great amp

I have several CT sounds products and they have never disappointed me in any way. I wanted some bass in my SUV without taking up too much space, so I have the AT 900.1 on a tropo xl 12 and I really like it. I also like having the voltage display on the remote gain. If I had to complain about anything, it would be the cheapy feeling of the plastic that the bass knob and volt meter is in, but that would be it.

Mike A
At 900.1d/1200

The amplifier has a great look to it. Love the base knob with the built in voltage readout and clipping light. Very clean sound and makes the subs hit hard. Running two 12" subs wired to 2 ohm load.