The Quilter Labs Bass Block V803 is a powerful and versatile bass amplifier that combines modern Class-D amplification with the warmth of vintage tube sounds. A robust 800W output ensures exceptional performance across various speaker setups, supported by a quiet, variable-speed fan for reliable, heavy-duty use.

Key Features:

· Power and Performance: Delivers over 800W to handle any speaker with ease. A high-current Class-D power section that combines old-school dynamic warmth with the efficiency of modern technology.

· Three Unique Amp Modes: The Voice switch provides three distinct amplifier profiles - MODERN (same system as prior 800 and 802 models, with tight solid-state output and "bottomless" limiter), WARM (tube-type output impedance with the same bottomless limiter) and Q-TUBE (tube-type output impedance with classic tube clipping) - each delivering a unique dynamic response ranging from tight, controlled solid-state performance to lush, vintage tube warmth and overdrive.

· Tone Shaping: A 3-band EQ with four controls (Bass, Midrange with sweepable frequency, and Treble) offers precise tonal adjustments.

· Connectivity and Controls: Includes two high impedance inputs (Flat and Scoop), FX Loop, headphone output with cab-sim, and an XLR Line Out with integral cab-sim and grounding switch. The GAIN control adjusts drive and sensitivity, while the MASTER control matches the output power to various speaker ratings.

· Additional Features: The rear panel offers dual Speakon™ Combo connectors for speaker compatibility, a locking AC cord for reliable power connection, and universal AC power support for use worldwide. The XLR Line Out pre-MASTER for consistent signal level regardless of where you set stage power.

· User Convenience: Features a MUTE-ACTIVE-PASSIVE switch with a bright LED indicator, and an FX Return that can be used as a stealth input for backing tracks. The headphone output automatically switches from FRFR on MODERN to cab-sim on WARM and Q-TUBE settings.

The Bass Block V803 is designed to meet the demands of professional musicians, providing robust performance and flexibility. Whether seeking the precision of modern amplification or the nostalgic tone of vintage tube amps, this amplifier provides high-quality sound and reliable operation in a compact, modern package.

Fits in our Block Case 2.0!

Features
- TWO INPUT JACKS: 2meg, Flat and Scoop, 4V peak
- INPUT SWITCH: Mute, Active, Passive
- GAIN
- AMP VOICE SWITCH: Modern, Warm & Q-Tube profiles
- 4-KNOB EQ: Bass +/- 15dB at 100Hz, Mid +/- 15dB with 250-1K Freq Sweep. Treble +/-15dB at 1kHz.
- EFFECTS LOOP: Buffered, 1K Send, 47K Return, 1V peak signal level
- XLR LINE OUT: 1.4V (+4dBu), 600 ohms balanced
- XLR GROUND LIFT: Ground, Lift Auto
- OUTPUT POWER: Up to 450W at 8 ohms, 800 watts at 4 ohms, 25Hz-15kHz
Controls
- Primary Controls
  - 3 VOICE SWITCH
  - INPUT SWITCH
  - 3-BAND ACTIVE EQ Boosts and cuts Bass, Mids, and Treble frequencies.
- Volume Controls
  - MASTER adjusts speaker power volume level. (0-800 watts)
  - GAIN regulates the overall input volume to the preamp.

Specifications

AMPLIFIER MODULE SPECIFICATIONS

Input (Flat or Scoop)	¼" mono, 2M, 4Vpk Passive, 12Vpk Active
FX Loop	¼" mono,1V full scale, 1K out, 47K Input (with FX Send lifted)
XLR Out (pre Master)	Balanced, 600 ohms, -6db. Ground lift switch.

Power

AC Power Req.	100–240Vac, 50–60 Hz, 500 W average, 1500W peak
Power Output - MODERN	250W - 16 ohm, 450W - 8 ohm, 800W - 4 ohm
Power Output - WARM, QTUBE	250W - 16 ohm, 450W - 8 ohm, 500W - 4 ohm
Headphone (post Master)	¼" TRS, 39 ohms each side
Speaker Output	4-8 ohms, 90V, 25A peak

Dimensions

H x W x D	3.125" H x 8.5" W" x 7.75" D (7.9375cm x 21.59cm x 19.68cm)
Weight	3.78 lbs (1.715 kg)

Resources
- The Wiki Page contains detailed info for setup and technical specs.

Bass Amplifiers