ADA1250 Amplifier

In stock
$2,400.00 USD

450 watts per channel for rooms over 2,500 cubic feet.

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ADA 1000 features.  Click to enlargeGetting the most out of your home theater and music listening depends on one thing: feeding it with enough power to really show off the quality of the system. High-end speakers need high-end power to show their capabilities, and the ADA1250 has that power in spades!

Why Power Is Paramount

If you under-power speakers, when they reach a challenging passage your amplifier will go into what is known as clipping, creating distortion as it struggles to keep up with the signal. That distortion is what we typically mean when we say something sounds 'too loud' - the displeasing noise stands out for us and we want to turn the sound down.

But when you have enough power going to all channels of your system, you'll never hear distortion. All you'll hear is the thrill of the action taking place - dynamic explosions, rousing crescendos - and the true capabilities of your high-end audio system.

How To Get It

Getting enough power means understanding the numbers. It seems straightforward: look at the number of watts-per-channel and get the one with the biggest numbers, right? But that's not really how it works. Amp power can be a bit confusing to understand because there are a number of specifications that need to be looked at together to determine exactly how much power you have available for music and movie playback. The standard way power is measured for an amplifier is a steady tone at 1 kHz into a resistor at either 2 ohms, 4 ohms, or 8 ohms and to a maximum distortion of 1%. This gives some consistency for comparison purposes but does not give us the whole story we need to know to determine how much power we actually have available for the dynamic playback of music and movies. Unfortunately, it can also cause a race between companies to get the highest possible wattage number when measured this way at the expense of the more important number, which includes time and distortion, generally referred to as clean dynamic headroom. Since music and movie soundtracks are never playing a constant tone at one power level the important thing to know is what happens when the amplifier is asked to play a very loud dynamic peak for a fraction of a second over and over again. Power is logarithmic, meaning an amplifier must double its wattage output for every 3 dB more of output you want to have. So if we use 15 dB as a desired amount of headroom for music and movie playback you will need a lot of power available for brief moments to achieve this without having the amplifier go into clipping or shutdown:

Continuous Average Output:

100 watts

3 dB of Dynamic Headroom:

200 watts

6 dB of Dynamic Headroom:

400 watts

9 dB of Dynamic Headroom:

800 watts

12 dB of Dynamic Headroom:

1600 watts

15 dB of Dynamic Headroom:

3200 watts

This makes it very important to know what happens when the amplifier is asked to exceed its rated continuous output for a brief moment in time. If the amplifier has no ability to produce short bursts of power beyond its rated continuous power then you can look at this equation in reverse. Let’s say the amplifier has a rated continuous output of 400 watts with no headroom above this, which is typical of amplifiers that use switching power supplies:

15 dB peak:

400 watts

12 dB peak:

200 watts

9 dB peak:

100 watts

6 dB peak:

50 watts

3 dB peak:

25 watts

Continuous Average Output:

12.5 watts

If the amplifier is using a switching power supply with a max rated power equal to the continuous rated power of the amplifier, with one channel driven, and little or no capacitance storage you will be severely limited in your real output capabilities to all channels. Virtually all receivers are constructed this way. All Axiom power amplifiers use what is called a linear power supply. This combination of a toroidal transformer and lots of storage capacitance means you have usable power many times the continuous rated power and that means loud and clean listening for you.

The massive analog power supply partners with the Axiom Digital Amplifier to exceed 90% efficiency: compare that to the typical Class A/B design you find in most amplifiers that waste nearly half the output from the amplifier in heat! Think about the numbers: a typical wall plug is capable of producing 1800 watts on a regular 15 amp circuit. The Axiom Digital Amplifier is so efficient, you can easily achieve 1000 watts of total continuous output: approximately double what a Class A/B design can provide. Add to this the massive capacitance storage in all Axiom amplifiers and you have available clean dynamic power available to your system many times the Continuous RMS wattage rating.

Which Axiom Amplifier Is Best For Me?

For rooms under 2,500 cubic feet and normal sort of volume levels the 1000 series is perfect.

For rooms over 2,500 cubic feet or if you like to really crank it once and awhile then the 1250 series is the one.

For huge rooms and/or the desire to the nirvana of loud and clean the 1500 series is the answer.

Axiom amplifiers can be connected to either the pre-amp outputs on your receiver (check your receiver has these) or to a stand-alone pre-amp processor.


Axiom's ADA Series amplifiers bring more dynamic headroom - which means more detail, clarity, and realism - to your audio experience. You can never have too much power, and the ADA amplifier series is here to give you every last ounce of awesomeness out of your loudspeakers. What can you expect to hear when you've got enough power? No distortion, and no clipping. Hear what you've been missing.

Questions We Get All the Time



Weight (lbs) each 53
Weight (kg) each 24
Dimensions H W D (inches) 5.25" x 17.75" x 16.75"
Dimensions H W D (mm) 133 x 450 x 425
Frequency Response (6 ohms -3dB) 1Hz - 45kHz
AC Input Voltage 115 or 230
RCA Input (Single Ended) Yes
Sensitivity (Full Power into 8 ohms) 1.5 volts
Signal to Noise Ratio (Input shorted, 22Hz-20kHz un-weighted, referenced to full power @8ohms) 103dB
12 Volt Trigger Yes
Voltage Gain 29dB
XLR Input (Balanced) Yes
Capacitance 108,000uf
Item Returns This item can be returned
Continuous RMS Wattage per channel into 8 ohms 225 watts
Continuous RMS Wattage per channel into 4 ohms 450 watts
Continuous RMS Wattage available to all channels 1250 watts
Dynamic Wattage available to all channels 3750 watts

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