The NuPrime STA-6 Stereo Amplifier (Commercial)

NuPrime audiophile quality commercial products are typically not sold in retail stores. The commercial product line is not designed for style but performance can be sound quality can be just as good as the home product line.

Class A+D Stereo Amplifier Brigeable into a 160 watt Mono Amplifier

With 2 X 90W Class A+D stereo amp, bridgeable into a 160W mono amp, STA-6 is designed with enhanced even-order harmonic circuitry that produces sonic characteristic similar to NuPrime STA-9, but leaning toward neutral with a slight hint of warmth. The STA-6's spacious, transparent, dynamic and luxuriously textured soundstage has to be heard to believed.

The STA-6 amplifier is derived from the Single End Class A Module + Class D design first introduced in the STA-9. By joining a powerful high impedance singled ended amplifier circuit in the preamp stage with a well integrated Class-D power stage, the STA-6 offers the richness of Class A sound with the remarkable speed and clarity of NuPrime Class-D design. Audio enthusiasts are bound to be impressed.

The NuPrime amp circuit improves on traditional Class-D design by using a self-oscillating circuit to generate pulse-width modulation. The amplifier switches at a frequency of 500kHz, well beyond the compact disc’s 44.1kHz sampling rate. Most class-D amps switch at 300kHz or lower. A new low noise switching power supply is designed specifically to complement the STA-6 amplifier. The overall result is unprecedented transient speed, smooth with lots of details and an almost shocking level of dynamic impact.

The STA-6's frequency response to 50 kHz elevates vocals into emotional experiences; similarly, instrumental upper registers mimic a live performance’s shimmering heights.

The STA-6 is designated for NuPrime Commercial product line and it is designed to be highly reliable under no-load condition and enhanced short circuit protection.

Specifications:

Inputs: RCA: Un-Balanced input x 1 THD+N: 0.01% (Stereo) / 0.01% (Mono)
Outputs: Stereo Speaker Out x 1 or Mono Speaker Out x 1 Frequency Response: 10Hz to 50kHz
Power: 2 x 90W / 1 x 160W @ 8 & 4 Ohms.
Same power at 8 & 4 Ohms as the
output power is limited by the power supply.
Worldwide AC voltage: 90 VAC~250 VAC
Input Impedance: 47k Ohms Dimension: 200 mm W x 184 mm D x 60 mm H (including feet)
Gain: x 28 Weight: 1.65kg
Signal to Noise Ratio: > -90dB at 1W, 10W, 100W With Package Weight: 2.2kg
Color: Black    

Frequently Asked Questions

MCH-K38 front panel buttons and LED lights

The buttons on the front panel are toggle on/off switch. 

Power button:  Red means Standby and Green means power on.  No Light means AC power switch off.

Channel 1 ~ 8, Red light means the source is set to XLR and Green means the source is set to RCA.  No Light means the channel is turn off.

The light in between 1 & 2, 3 & 4, 5 & 6, and 7 & 8 are Mono indicators.  Red light also means the source is set to XLR and Green means the source is set to RCA.  No Light means the channel is turn off.  The mono channel can be toggled on/off with channel 2, 4, 6, & 8. 

Please make sure to press the buttons to turn on the channels.  Since our stereo lights are very small LED on the button top, so it might be easy to miss if its put inside the rack.

What some of the amps have the same power rating at 8 and 4 Ohms ?

There is two side to a coin. The truth is that the amp is capable of more power than the spec suggested. So if 4 and 8 Ohms are specified at 100Wx2, that means the power supply is a 200W PSU. And we are extremely conservative about our power rating (we provide conservative RMS rating, not peak power). A customer reported 180W for IDA-8 because he is using just one channel to do the measurement. So, if IDA-8 is in a bigger case, and we put in a 300W PSU, you will see a higher rating. In reality, you get more than 100W per channel from the 200W PSU, because not both channels are driven at the same time.

Why don't we put in a bigger PSU? Each model is designed for specific product position and adding more power will certainly increase the cost and size of the product.

Can the amplifier's speaker terminals be used as source inputs (e.g. to REL Subwoofer) ?

In some applications, the speaker outputs from the power amplifier are used as source signals for devices such as REL sub woofer. For such application, usually the receiving devices should have DC offset blocking capability because some amplifier by design has floating ground (DC offset) on the speaker outputs. 

The following models have no DC offset on the amplifier speaker outputs and the negative terminal is also the ground:

NuPrime STA-9, MCH-K38, IDA-16

The following models' speaker outputs can not be connected directly to sub woofer input:

NuPrime Reference 20, ST-10, IDA-8

What kind of trigger cable can be used for your products?

When a device has a 12V trigger input, it is designed to be turned on when a 12V is detected. You can use any standard male to male 3.5mm (3-pin type) cable.