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Zapco introduced the industry to great sounding Class D amplifiers some 10 years ago with the famous 9.0XD. In those days, the filtering and control systems needed to make Zapco sound quality in a Class D amplifier meant it had to be expensive and it had to be big.

Today's technology, however, has allowed us to develop a line of great sounding full range Class D amps at an affordable price range and in a size that's an easy fit in today's smaller cars. Small car doesn't have to mean small sound, and you won't have to give up the back seat for an amplifier. And even motorcycles. In fact, at only 6.3" x 6.7", the ST2D is the ideal amplifier for a motorcycle faring. Small size, big power. And talk about POWER! This tiny little monster is going to give you 400watts RMS. With that kind of power in your faring, you're going to need louder pipes, and, since these little power houses are Zapco amps, you know they're going to sound great.

Just like with the Z-Series and the ZX-Series, we kept the ST-D series simple. The feature set is kept to the essentials. They all have 18dB crossovers, speaker level inputs, and optional remote level controls, but, they don't have chrome or fancy paint jobs, and they don't look like hot rod engines or computers. They look like car audio amplifiers. We put our efforts (and your money) into great sound and reliable power.

Even though they're Class D they have less than 0.05% THD+noise and 90dB signal to noise ratio. After all, loud is no good unless it sounds great as well. And these new amplifiers sound awesome. Audition one today and you'll know what we mean.
Even though the 2ch, 4ch, and 5ch powerhouses have way more punch than you'd expect from such a diminutive chassis, we know you're going to want dedicated bass amps as well. And the ST-D series has 'em! You can choose 500 watts at 1 ohm or 1,000 watts at 1 ohm, and even the 1,000 watt amp is less than 10" long.
The ST-Series D Full Range Class D Amplifiers
ST-2D - 2 Channel Class D Full Range Amplifier
The ST-2D. This little powerhouse has 100w RMS /Ch @ 4 ohms and 200w RMS/Ch @ 2 ohms with 400w RMS at 4 ohms mono. All this with <0.05% THD, 90dB S/N, Electronic Crossover and a Variable Bass Boost.


-Class-D bridgeable 12V amplifier
-2/1 channel bridgeable 12V amplifier
-Stable into 4 ohms bridged or 2 ohms stereo load
-PWM MOSFET power supply
-18dB octave crossover slope
-Variable FULL / LP / HP Electronic Crossover -Variable bass boost
-RCA Signal input and output connectors
-4-way protection circuitry
-thermal / over current / speaker short / DC
-Tested voltage & THD: 14.4V & less than 0.05%
-Dimensions in Inches : 6.7(W) x 2.2(H) x 6.5(L)
Stereo, 4 ohms: 2 x 100 Watts
Stereo, 2 ohms: 2 x 200 Watts
Bridged, 4 ohms: 1 x 400 Watts
T.H.D. + Noise: <0.05% @ 4 ohms S/N Ratio: 90dBs.
Specifications:
ST-4D - 4 Channel Class D Full Range Amplifier.
The ST-4D is only an inch and a half longer than the ST-D2, The ST-D4 has 4 x 100w RMS /Ch @ 4 ohms and 4 x 160w RMS/Ch @ 2 ohms with 340w RMS/Ch at 4 ohms Stereo. All this with <0.05% THD, 90dB S/N, Electronic Crossovers and a Variable Bass Boost SP.


-Class-D bridgeable 12V amplifier
-4/2 channel bridgeable 12V amplifier
-Stable into 4 ohms bridged or 2 ohms stereo load -PWM MOSFET power supply
-18dB octave crossover slope
-Variable FULL / LP / HP Electronic Crossover -Variable bass boost
-RCA Signal input and output connectors
-4-way protection circuitry
-thermal / over current / speaker short / DC
-Tested voltage & THD: 14.4V & less than 0.05% -Dimensions in Inches : 6.7(W) x 2.2(H) x 7.87(L)
Stereo, 4 ohms: 4 x 100 Watts
Stereo, 2 ohms: 4 x 160 Watts
Bridged, 4 ohms: 2 x 160 Watts
T.H.D. + Noise: <0.05% @ 4 ohms S/N Ratio: 90dB
Specifications:
ST-5D - 5 Channel Class D Full Range Amplifier
The ST-5D has 4 x 75w RMS /Ch plus 1 x 225w RMS @ 4 ohms and 4 x 100w RMS/Ch plus 1 x 350w RMS@ 2 ohms. All this with <0.07% THD, 90dB S/N, Electronic Crossovers and a Variable Bass Boost.


-Class-D bridgeable 12V amplifier
-5/3 channel bridgeable 12V amplifier
-Stable into 4 ohms bridged or 2 ohms stereo load -PWM MOSFET power supply
-18dB octave crossover slope
-Variable FULL / LP / HP Electronic Crossover -Variable bass boost -Variable sub sonic filter
-RCA Signal input and output connectors
-4-way protection circuitry
-thermal / over current / speaker short / DC
-Tested voltage & THD: 14.4V & less than 0.05% -Dimensions in Inches : 6.7(W) x 2.2(H) x 10.5(L)
Stereo, 4 ohms: 4 x 75 Watts Plus 1 x 225 Watts Stereo, 2 ohms: 4 x 100 Watts Plus 1 x 350 Watts Bridged, 4 ohms: 2 x 210 Watts Plus 1 x 350 Watts T.H.D. + Noise: <0.06% @ 4 ohms S/N Ratio: 90dBs.
Specifications:
ST-500DM - High Power Class D Mono Amplifier.
The ST-500DM has 160w RMS @ 4 ohms, 310w RMS @ 2 ohms and 500w RMS @1 ohm. It has a 30Hz sub sonic filter and an 80Hz 18dB/octave Electronic Crossover.



-Class-D bridgeable 12V amplifier
-Single channel mono 12V bass amplifier
-Stable from 4 ohms to 1 ohm load
-PWM MOSFET power supply
-18dB octave crossover slope -80Hz sub crossover -30Hz Sub Sonic filter
-Optional dash control for bass level
-RCA Signal input and output connectors
-4-way protection circuitry
-thermal / over current / speaker short / DC
-Tested voltage & THD: 14.4V & less than 0.2% -Dimensions in Inches : 6.7(W) x 2.2(H) x 7.5(L)
Mono 4 ohms: 1 x 160 Watts
Mono 2 ohms: 1 x 310 Watts
Mone 1 Ohm 1 x 500 Watts
T.H.D. + Noise: <0.2% @ 4 ohms S/N Ratio: 90dB.
Specifications:
ST-1KDM - High Power Class D Mono Amplifier.
The ST-1KDM has 360w RMS @ 4 omhs, 700w RMS @ 2 omhs and 1,000w RMS @1 ohm. It has a 30Hz sub sonic filter and an 80Hz 18dB/octave Electronic Crossover.


-Class-D bridgeable 12V amplifier
-Single channel mono 12V bass amplifier
-Stable from 4 ohms to 1 ohm load
-PWM MOSFET power supply
-18dB octave crossover slope
-80Hz sub crossover
-30Hz Sub Sonic filter
-Optional dash control for bass level
-RCA Signal input and output connectors
-4-way protection circuitry
-thermal / over current / speaker short / DC
-Tested voltage & THD: 14.4V & less than 0.05% -Dimensions in Inches : 6.7(W) x 2.2(H) x 9.8(L)
Mono 4 ohms: 1 x 360 Watts
Mono 2 ohms: 1 x 700 Watts
Mone 1 Ohm 1 x 1000 Watts
T.H.D. + Noise: <0.2% @ 4 ohms S/N Ratio: 90dB..
Specifications: