RELENTLESS 800
MONOBLOCK AMPLIFIER

AN UNRELENTING STANDARDDan D’Agostino Master Audio Systems set the standard for amplifier performance with the Relentless Epic 1600
Monoblock Amplifier. Now, the Relentless Series expands its reach with the Relentless 800 Monoblock Amplifier.
Every major section of the Relentless Epic 1600 has been incorporated into the Relentless 800, whose design
is further enhanced by new power management topology that isolates the power supply from the entire audio
circuitry, providing extra protection from noise generated by the amplifier’s massive power transformers.
ADVANCED TOPOLOGY, UNCOMPROMISING PERFORMANCEThe Relentless 800 Monoblock Amplifier employs all-new, fully complementary topology based around a precision
input stage that maintains a perfect balance between the positive and negative components of the signal. Gaincircuits operate in the current domain, assuring that performance does not fluctuate, regardless of speaker demand.
New input stage devices deliver a 300% increase in current as compared to the devices previously employed.
These wider-bandwidth, higher-power components extend low- and high-frequency performance with reduced
distortion. Global negative feedback is not required, as the amplifier’s open-loop linearity eliminates the need forthis performance-robbing technique. Crucial to the new circuit are the bipolar transistors powering the front end.
Activating the driver stage is a new bias stability circuit providing a nearly 50% increase in operating bias. Increasing
Class A operation directly correlates to better sound quality. The new bias scheme ensures bias consistency,
preventing excessive temperatures even under the greatest demand. Additional regulation circuitry prevents any
AC power anomalies from upsetting the amplifier’s input circuitry.
STANDARD-SETTING OUTPUT STAGE
A critical element of any amplifier output topology is the driver section, and here, the driver transistor has been
upgraded to a new device that handles 33% more power per device. Additionally, the driver transistor count has
doubled, minimizing demand on each device and lowering overall amplifier output impedance without resorting
to global negative feedback. Individual transistors are used for the positive and negative signal elements, nearly
doubling the current drive necessary to maximize the enhanced output stage. The output stage features the samenew transistor used in the driver section for sonic and technical consistency. Individual, complementary pairs
undergo our transistor matching protocol to ensure that gain linearity is virtually identical from 50mA to 5A. Each of

the 84 high-output transistors, among the fastest available, is mounted with two stainless steel fasteners—ararity among ﬂat-package transistors—for maximum thermal transfer to the copper heat sinks. A capacitor/resistor
network connected to the base of each transistor guarantees stability, even at high frequencies and with lowimpedance speakers. As with all Dan D’Agostino Master Audio Systems components, the Relentless 800 features
discrete, direct-coupled, balanced circuitry—the most accurate circuit platform possible.
IMPOSING POWER AND FORM
With its dual-transformer, dual-rectification transformer arrangement and 400,000 µF capacitance power supply
feeding 84 output devices, the Relentless 800 easily delivers 800 watts into 8Ω—and when connected to a 220volt outlet, it doubles its output to 1,600 watts into 4Ω and 3,200 watts into 2Ω. A special holder mechanicallygrounds each capacitor, eliminating vibrations. A slow-start circuit activates the power supply in stages,
eliminating concerns about capacitive in-rush tripping circuit breakers. D’Agostino’s exclusive Super Rail concept
employs higher voltage rails in the sections prior to the output stage, effectively “turbocharging” the amplifier andexploiting the full capability of the output voltage rails—which improves dynamics, lowers distortion, and tightens
the amplifier’s electrical grip on the speaker. The unique heat sink design combines copper and aluminum in athermal engine that wicks away heat from the connected output devices, ensuring safe and reliable operation evenwhen delivering full-rated power. Thermal, short-circuit, and DC protection are a non-invasive but comprehensive
defense against external system faults.
The entire chassis of the Relentless 800 is machined from solid aluminum for superior shielding, thermal stability,and vibration damping. High-precision milling allows the entire chassis to fit together solidly, with no visible
fasteners. Each Relentless 800 Mono Amplifier is hand-built and individually tested in D’Agostino’s Arizona factoryby our team of technicians and craftsmen.

S P E C I F I C AT I O N S

Frequency Response

20 Hz to 20 kHz, ±0.1 dB

Signal-to-Noise Ratio

113 dB, wideband, unweighted,
ref. to full power output
80 dB, A weighted

Input Impedance

120 MΩ

Power Output

800 watts @ 8Ω / 1,600 watts @ 4Ω / 3,200 watts @ 2ΩDistortion

800 watts @ 8Ω 0.1% @ 1 kHz

Inputs

1 balanced XLR

Outputs

1 pr Speaker Binding Post

Dimensions

21.6 x 10.4 x 26.0 in / 54.9 x 26.4 x 66.0 cm

Weight

320 lb / 145 kg

FinishSilver / Black / Custom finishes© 2023 Dan D’Agostino Master Audio Systems, LLC. All rights reserved.

dandagostino.com / 480.575.3069