Zapco ST-850XM II

The square, low profile chassis also means it will be easy to trim out for a great looking installation so your system will look as awesome as it sounds. And speaking of sound…This is a Zapco amplifier and sound is what it’s all about. These are Class A/B Zapco amplifiers.

The Studio-X have the same high quality caps, op-amps, and bi-polar outputs that made the C2K and Reference series amps the industry standard for sound quality.

Reliability? Zapco defines reliability. It’s not at all unusual to see Zapco amps moved from car to car and from generation to generation. Zapco Amps produced in the ‘90 are still being traded and bought on the internet by sound quality fans world wide. The Studio-x will be no different.

Studio-XM Class D Bass Amplifiers

Bass is only a small part of most any musical pieces, but it is what sets the mood for everything else. And, although everyone wants bass, everyone’s needs for bass are not the same. In the Studio-X line we have six Class D, mono bass amplifiers, ranging from 500 Watts RMS to 2,000 watts RMS. And if that is not enough for you… all the Studio-XM amps can be strapped together to a single voice coil, so you can always double you power by just buying another of the same model amp.

All the ST-XM Class D bass amps are 1Ω stable as necessary in today’s market. However, we also see a strong need to provide power to a 2Ω load in the medium power ranges for the sound quality fanatic in all if us. The 2Ω load, is a more efficient use of current and is better for sound quality. The ST-850XM and the ST-1350XM were both designed to have maximum efficiency and produce over 70% of their power into a 2Ω load with 600W RMS and 970W RMS respectively. With RMS powers of 500W, 850W, 1,000W, 1350W, 1650W, and 2,000W, and the ability to strap together, the ST-XM amps cover just about any need you might have from 500watts to 4,000 watts.

Here is what all the new ST-XM amps share:

• Remote Dash Control – All the ST-X amps come with a remote so you can change the bass output as needed instantly.
• Input Sensitivity (Gain) Control – Sets sensitivity anywhere 200mV to over 5 volts.
• Mono Bridge Out and Bridge In – These allow the bridging of two amplifiers together (Strapping). When the Bridge Out RCA from the main amp is connected to the Bridge RCA In of the slave amp, the main (out) amp will take priority for control. At that point you will make all adjustments at the main amp only and they will be duplicated in the slave amp.
• Low Pass Crossover – Intended only as bass amplifiers, all the ST-XM amps have a full time low pass crossover variable from 40 to 180Hz.
• Sub Sonic (HP) Filter – Reproducing frequencies below those you want to hear wastes amplifier power. The Sub Sonic filter helps save that energy for the frequencies you do want to hear. More importantly, trying to reproduce frequencies below the range of the woofer can quickly destroy your woofer. This is especially important for ported enclosures. i.e. If your enclosure is ported 40Hz then you should set you Sub Sonic to 40 Hz to protect your
• subwoofer investment.
• Bass Boost Control – All the ST-XM amplifiers have a variable bass boost. You can vary the amount of the bass boost from 0dB to 12dB as needed for your particular installation.
• Bass Frequency Control – Fact: No two cars are the same. The bass response of a woofer will be different in every car you put it in, so a bass boost at 50Hz can be great for one car but useless in another. The ST-X Bass Frequency control allows you to set the bass boost at any frequency from 30Hz to 80Hz, so you can set it precisely to match your music in your car.
• Phase Control – Facing you bass enclosure to the front will sound different than facing it to the rear. In either case, changing the phase of the woofers will also make a difference. The problem is you won’t know which is best until the system is installed. Then you can listen each way to see which way the bass sounds best. The phase control on the ST-XM amps lets you adjust the phase of the signal right at the amp. In addition the ST-XM phase control is variable from 0° to 180° so you can dial in exactly the phase relationship that works best in your car.

Features and Functions:

• Single channel, Class D, Bass Amplifier
• Compact chassis
• Variable input gain control
• Variable electronic crossover
• Variable subsonic filter
• Variable bass boost control
• Variable center frequency for bass boost
• Variable phase control
• Strappable to use a pair of amps on a single voice coil
• Dash mount remote gain control

Specifications:

• Power @ 1Ω: 1 x 850 watts
• Power @ 2Ω: 1 x 600 watts
• Power @ 4Ω: 1 x 400 watts
• Signal to Noise Ratio > 85dB
• THD @ Rated Power < 0.2%
• THD + Noise < 0.2% Efficiency > 85%
• Frequency Response 10Hz to 200Hz ±1dB
• Input Sensitivity .25v to 5v
• Dimensions in mm: 160(W) x 52(H) x 301(L) Overall: 160(W) x 52(H) x 326(L)