My account

Zapco ST-4X DSP III amplifier

4-channel amplifier with DSP processor, 4 x 65 / 2 x 180 W RMS (4 Ω), class AB
More about the product
We will help you with your purchase
Zapco ST-4X DSP III amplifier
Tip

Zapco ST-4X DSP III amplifier

Zapco's Studio-X range of amplifiers has been designed specifically for today's car audio market. Studio-X's compact chassis allows for easy installation in any car, and the modern angular design will make your sound system look as great as it sounds. And speaking of sound... This is a Zapco amp, where sound quality always comes first. However, durability and reliability are also among the main advantages. It is not at all unusual to see Zapco amps being passed from car to car and generation to generation. Zapco amplifiers made in the 1990s are still traded and purchased online by audio quality enthusiasts around the world. The Studio-X range of amplifiers will be no different as they are designed to last for decades.

Zapco Studio-X class AB amplifiers

In 2022, Zapco comes with six innovative class AB amplifiers in its third generation. The chassis of the amplifier is completely new, with brushed aluminum replacing the black color, and several modifications have been made to the internal components to take the sound quality up another notch. Also new are internal fans with temperature control, which will ensure that your amplifier will play all day without problems of overheating. All amps use bipolar output devices for the smoothest possible sound. ST-X amplifiers share variable electronic HP/LP/Full Range crossovers, variable bass gain, variable gain by channel pair, speaker level input, heavy-duty positive-locking terminal blocks, and preamplifier outputs for chaining to another amplifier in your system without you would have to add additional RCA cables. And the most important feature shared by all ST-X amplifiers is Zapco's legendary sound quality, developed with over 40 years of experience. The ST-4X DSP III amplifier includes an integrated DSP processor with enhanced high-speed (96 kHz) digital signal processing for 8 channels, so that up to two additional amplifiers can be connected and set up on the DSP processor. The Zapco ST-4X DSP III has analog inputs with control lights for the most accurate setting of the input signal and an optical SPDIF digital input. Connectivity is also enabled by the communication port, to which you can connect the Zapco HD-BT bluetooth module for streaming music in hi-definition format.

The main features of the Zapco ST-4X DSP III amplifier

  • 4-channel class AB amplifier with 8-channel DSP processor.
  • Power 4 x 65 / 2 x 180 W RMS (4 Ω), 4 x 90 W RMS (2 Ω).
  • Brushed aluminum chassis with temperature controlled fan.
  • Stable up to 2 Ω, in the bridge up to 4 Ω.
  • RCA and high-level inputs.
  • Optical digital input.
  • Automatic switching thanks to the Auto Turn On function.
  • Stable Tiffany RCA connectors.
  • 15-band parametric EQ, HPF, LPF, phase, time correction, etc.
  • Socket input terminals.
  • Optional bluetooth module for Hi-Res music streaming.

About Zapco Amplifiers

Zapco is the oldest high-end car audio brand in the world, specializing in high-end car amplifiers and DSP processors. The company was founded in the USA back in 1974 and has been collecting one award after another since then. And this both from prestigious organizations that evaluate the quality of products and innovations, as well as at global competitions focused mainly on sound quality. Zapco amplifiers represent audiophile quality without compromise, defining the standard of quality and setting the criteria by which other products in the industry are judged. At Zapco, for over 45 years, they have been constantly looking for innovative ways to bring better sound to the automotive environment, and this relentless pursuit of absolute sound quality has always resulted in new technologies and high-end products. Are you asking why? Because nothing else can capture the soul and bring tears to the eyes like music. Music can make you dance for joy..... of all the arts, music has the most powerful and immediate effect on your body and mind. Reproducing music in all its beauty and delicacy deserves nothing less than the best efforts of all Zapco employees. And also because music matters!

Catalog numberST-4X DSP III
BrandZapco
LinksOfficial web presentation (English)
Number of amplifier channelsAmplifiers are divided into:
- Monoblocks
- 2-channel
- 3-channel
- 4-channel
- 5-channel
- 6-channel
- multi-channel

Each channel is used to power one speaker for the coaxial type, or one side if they are component speakers.

Monoblock type amplifiers are mainly used for subwoofers.

2-channel are suitable for both subwoofers and, for example, the front pair of speakers in a car.

3-channel is used for front or rear speakers + subwoofer.

4-channel are used for front + rear speakers or 1 pair of speakers + subwoofer.

6 or 5-channel are used for 2 pairs of speakers + subwoofer, most often.

Bridging means connecting the amplifier to a bridge, using the + pole from one channel and the - pole from the other channel. In most cases this is shown as "BRIDGED" on the amplifier.
4
Energy class of the amplifierAmplifiers are divided into two basic classes: analog and digital . Analog amplifiers (A/B) have higher consumption requirements, but usually have a more natural sound. Digital amplifiers (D) have significantly lower consumption and higher efficiency, but the sound may not be as faithful as with classic analog amplifiers. A/B
RMS power into 4 ΩRMS power when loading speakers or subwoofer at 4 Ω. RMS power is the constant power of the amplifier and is one of the most important parameters when choosing an amplifier. 4 x 65 / 2 x 180 W
RMS power into 2 ΩRMS power when loading speakers or subwoofer at 2 Ω. RMS power is the constant power of the amplifier and is one of the most important parameters when choosing an amplifier. 4 x 90W
Frequency rangeThe ability of the amplifier to reproduce the signal from the lowest frequency to the highest = faithfully reproduce the sound in a specific frequency band.

Professionally:
In the frequency range from 40 to 16,000 Hz, the vast majority of fundamental and overtones (harmonics) of all musical instruments are found. We are interested in the course of the radiated sound pressure in this range of frequencies when the loudspeaker system is supplied with constant power. We call this course the frequency characteristic, which tells us the level of radiated sound pressure in decibels (dB) depending on the frequency. The frequency characteristic of a speaker or speaker system can be expressed most succinctly with a graph.

Mostly, however, the frequency characteristic is indicated by indicating the maximum tolerance of the sound pressure in the given frequency range, e.g. 50 to 15,000 Hz -+ 6 dB. Since the frequency characteristics of loudspeakers and systems in general are quite uneven, some manufacturers do not even specify this maximum tolerance of sound pressure in decibels in their catalogs for reasons of prestige. Data impoverished in this way is unfortunately worthless. What is valid is that the manufacturer offers a speaker system with a frequency range of 30 to 20,000 Hz, if he is worried about stating the maximum unevenness of the sound pressure in this range, because he can have a tolerance of, for example, +- 20 dB.

The unevenness or undulation of the frequency curve in good speaker systems for high-quality music performance should not exceed +-3 dB in the 80 to 12,000 Hz band and +-6 dB in the 40 to 16,000 Hz band. Greater unevenness already depletes or emphasizes certain tonal areas, which can cause audible or even disturbing distortion. The proportion between fundamental tones and higher harmonics also changes, thereby changing the color of the sound, and individual musical instruments as well as the entire musical image sound unnatural.
15 - 30000 Hz
Harmonic Distortion (THD)Total harmonic distortion indicates how much the input signal is distorted in the amplifier. Distortions appear as overtones contained in the output signal. The proportion of originally absent parts of the signal is given as a percentage, typical values are between 0.001% and 0.5%.

Distortion is measured in their power band. If it exceeds the limit of 0.7% from a certain power, it is the value of the output power of the given amplifier, from which it no longer plays without distortion and from which the distortion usually increases steeply, so that no further increase in power can be counted on. The lower the value, the better.
< 0.2%
Signal-to-noise ratioThe signal-to-noise ratio means that the output signal always contains noise. The signal-to-noise ratio expresses how much of this noise is compared to the useful signal. The so-called A value is given, which does not take deep and very high frequencies into account. This corresponds to the characteristic of human hearing, which is not so sensitive to deep frequencies, especially below 1 kHz. The higher the value, the better the amplifier is. > 90 dB
Input sensitivityIn order for the amplifier to perform its function correctly, it requires an input signal of a certain level, which is different for car radios. It is measured in "Volts" (e.g. 2 V, 4 V, etc.) The higher the value at the output of the pre-amplifier, or car radio, the less demands are placed on the power of the amplifier. However, the amplifier must allow this input sensitivity, and for that reason this value is also given for the amplifier. 0.25 - 5V
High level inputsThe high-level input on the amplifier allows connection directly to the existing speakers in the car without additional purchase of an external high/low adapter. Important equipment in the case of installing an amplifier on an original car radio. Yes
Automatic on and offThis function allows you to automatically switch on the amplifier. Yes
Socket input terminalsFerrule terminals allow better wiring contact to the amplifier. It is also a more secure form of terminals. If you are tightening the sleeve terminals, we recommend retightening them after 1 day, as the connected cable gradually compresses. Yes
The value of the fuses on the amplifierFrom the value of the fuses on the amplifier, you can get a true picture of the real performance of the amplifier. 2 x 30A
Dimensions of the amplifier160 x 57 x 284 mm

Product comments

Evaluation

Overall rating
100 %
1 customer rated
Rate the product:
ask us
We will only use your data to send you a reply.