Completed Stereo Integrity SIQ 75.4 4-channel class A/B amp. A thing of beauty to the ears!

Doxquzme
Premium Member

Current build, 2012 Mazda 3 Hatch 2.5T
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Price
$349
Condition (1 worst - 10 best)
10
Location
Boise, ID

(Price is shipoped lower 48)

These are the real deal SQ amplifiers. You have to pay quite a bit more to equal the sound quality, the clarity, and the sparkle these amps provide. It's a pure signal path to the amplifier sections, no electronic crossovers, and nothing between the signal you give it and the amp section except for a gain control.

This amp is new, opened to bench test only, and never installed! I've repackaged it even better than the way it came.

From SI

Hi-Fi class A/B and class D amplifiers are back with our SIQ amplifiers. Full bandwidth, zero filters, discrete gain knob per channel, zero crossovers, zero EQ. Purity at its finest. Being avid audiophiles for over 25 years we have always appreciated the finer performing amplifiers in mobile audio and with our growing presence in the mobile audio industry, we have been able to team up with talented amplifier engineers and finally produce our own hi-fi amplifiers. Audiophile components were used throughout construction and engineering to bring our amplifiers to fruition. And because we are a direct company (no dealers) the cost savings are passed directly to you, our customers.

All of our SIQ class A/B amplifiers utilize audiophile-grade T0-3 output transistors, clean board layouts, thick extruded aluminum chassis, copper anodized shielded transformer covers, and a large plexiglass viewing window. Coming inward we use UPC4570 op-amps followed by IRFPO64N power supply transistors, sand cast resistors, surface mount parts to save board space, and Tiffany-style RCA connections. All of the above FR and power graphs are from Audio Precision measurements.

Amplifiers Specifications​

Quick Info​

Frequency Response Minimum5 Hz
Frequency Response Maximum150,000 Hz
Signal-to-Noise Ratio (SNR)90 dB
Total Harmonic Distortion (THD)0.03 %
Dimensions (W x H x D)14 x 8 x 2 Inches
Rated RMS power output into all 4 channels at 4 ohm75 Watts
Rated RMS power output into all 4 channels at 2 ohm120 Watts
Bridged RMS power into 2 channels at 4 ohm120 Watts

Connections​

RCA Input Maximum16 Volts

Power​

Idle Current Draw1.2 amps
Maximum Current Draw66 amps

Price is shipped to the lower 48—payment by PayPal F&F unless you want to pay the fees for PayPal G&S.
 
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Doxquzme

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Current build, 2012 Mazda 3 Hatch 2.5T
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