Bass Block V803
Bass Block V803
800 Watts. Under 4 Pounds. Your Cab Has Never Had It This Good.
THREE WORLDS ONE SWITCH
This isn't a modeling amp. It's not switching between presets. When you flip the Voice switch on the V803, you're changing how the actual power section behaves at the circuit level.
Modern gives you solid-state output impedance with Quilter's bottomless limiter — tight, controlled, 800 watts into 4 ohms. The kind of clean headroom that makes your pedalboard sound exactly like it should.
Warm changes the power section to tube-type output impedance. Same bottomless limiter, but now your notes bloom. The speaker pushes back the way it does with a vintage tube head. Your fingers feel the difference before your ears hear it.
Q-Tube goes all the way — tube-type output impedance with real tube clipping. The sag. The grunt. The breakup that responds to how hard you dig in. The feel of a cranked SVT, from a box you can hold in one hand.
This is three whole dimensions of tone. One for every type of bass you want to play.
BOTTOMLESS
Every bass player knows the problem. You boost the lows, your B string flubs out and buries everything. You back off, and you lose the foundation. Traditional compression squashes the whole signal to fix it — your dynamics go flat and your tone turns into cardboard.
Quilter's exclusive dual limiter works differently. It controls the low frequencies independently — your lowest strings hit a wall before they bottom out, but your upper strings keep their full dynamic range. The overtones breathe. The D and G still cut. The low end stays massive and planted instead of flabby.
The result is an amp that feels like it has infinite power reserves. Push it hard and it pushes back musically — with grunt and effort instead of ugly breakup. Even with the BASS knob cranked, the lows stay controlled while the rest of your tone stays alive.
No other bass amp does this. Not at any price.
LIGHTER THAN...
Put the V803 next to everything in its class:
Same power. Less weight. Half the price. And none of those amps switch between three different power amp topologies.
This isn't a budget amp that cuts corners to hit a price point. This is Patrick Quilter — the "Q" in QSC Audio — applying 50 years of professional power amplifier design to a bass head. The same Q-Circuit technology that powers Quilter's guitar amps, purpose-built for bass. 4-band EQ with sweepable mids, dual inputs, effects loop, pre-Master XLR direct out, headphone output with automatic cab simulation, universal voltage, and a variable-speed fan that stays quiet under load.
3.78 pounds. Block Case 2.0. Walk to the gig. Be the bad ass you always knew you were.
Hear It For Yourself
Bass Block V803 In Action
$699
or as low as $59/mo with Shop Pay
What a comparable tube bass head costs you
All-tube bass head (300W, giggable)$2,500–$3,500
Power tube set — 6x 6550s (every 2–4 yrs)$200–$400
Bias adjustment (per retube)$75–$100
Weight penalty (65–85 lbs + road case)Priceless
Cab to handle 300W (matching 8x10 or 4x10)$800–$1,500
5-year cost of ownership$3,800–$5,500+
Bass Block V803 — 800W, 3.78 lbs, zero maintenance$699
In the 800-watt class
V803
$699
800W · 3.78 lbs · 3 voices
GK Legacy 800
$1,399
800W · ~5 lbs · 1 voice
Darkglass 900
$1,499
900W · 6.4 lbs · 2 drives
Designed by Patrick Quilter
•
The "Q" in QSC Audio
What $699 gets you
XLR Line Out
Headphone + Cab Sim
Effects Loop
Dual Speakon™ Out
Universal Voltage
Dual Inputs (Flat / Scoop)
Zero maintenance. Forever.
No tubes to replace
No bias adjustments
No warm-up time
No tech visits
The $699 is what you spend. Period.
Complete your rig
Block Case 2.0
Your entire 800-watt bass rig — head, cables, and case — in one hand.
Three Power Amps.
One Switch.
Not presets. Not modeling. The Voice switch changes how the actual power section behaves at the circuit level — different output impedance, different clipping behavior, different feel under your fingers.
Modern
Solid-state authority
Tight, controlled solid-state output with the bottomless limiter — 800 watts at 4 ohms, full headroom, zero flub. Your pedalboard sounds exactly like it should. The same power system as the Bass Block 800 and 802, refined.
Warm
Tube impedance, modern control
Tube-type output impedance with the same bottomless limiter. Your notes bloom and sag — the speaker pushes back the way it does with a vintage tube head. Low B stays planted while your overtones breathe. The best of both worlds.
Q-Tube
Full vintage clipping
Tube-type output impedance with real tube clipping behavior. The grunt. The sag. The breakup that responds to how hard you dig in. The feel of a cranked SVT — without the 85-pound road case or the $400 retube bill.
Controls
Gain
Bass
Mid
Freq
Treble
Master
Voice Switch
Input Switch
XLR Ground Lift
Six knobs. Three switches. No screens. No menus. No firmware updates.
Quilter Labs
How Bass Block V803 Compares
800W Bass Head — $699
| Quilter Labs BASS BLOCK V803 | Gallien-Krueger LEGACY 800 | Darkglass MICROTUBES 900 V2 | Mesa/Boogie SUBWAY D-800+ | |
|---|---|---|---|---|
| Price | $699 ★ | $1,049 | $1,499 | $999 |
| Power | 800W @ 4Ω | 800W @ 4Ω | 900W @ 2Ω | 800W @ 4Ω |
| Weight | 3.78 lbs ★ | 5.7 lbs | 6.4 lbs | ~5 lbs |
| Power Amp Topology Switching | ✓ 3 modes ★ (Modern / Warm / Q-Tube) |
✗ | ✗ | ✗ |
| Dual Limiter (Low-String Protection) | ✓ Quilter exclusive ★ | ✗ | ✗ | ✗ |
| Drive / Overdrive | ✓ Via Gain + Q-Tube | ✓ Footswitchable (G.I.V.E. circuit) |
✓ 2 voicings ★ (B3K / VMT) |
✓ 2 voicings (Voice 1 / Voice 2) |
| EQ | 4-band + sweepable mid (250Hz–1kHz) |
4-band active + Bump / Contour / Presence |
6-band graphic ★ | 4-band + 2 semi-para mids |
| Compression | ✗ | ✗ | ✓ Studio VCA ★ | ✗ |
| XLR Direct Out | ✓ Pre-Master (ground lift) |
✓ Pre/Post EQ | ✓ Dual XLR ★ (Pre + Post w/ cab sim) |
✓ Pre/Post EQ |
| Headphone Out | ✓ Auto cab sim | ✓ | ✓ With IR ★ | ✓ |
| IR / Cab Simulation | ✓ Auto (per voice) | ✗ | ✓ 3 IR slots ★ | ✗ |
| Effects Loop | ✓ | ✓ | ✓ | ✓ |
| Dual Inputs (Flat / Scoop) | ✓ ★ | ✗ | ✗ | ✗ |
| MIDI | ✗ | ✗ | ✓ ★ | ✗ |
| USB / Software Editor | ✗ | ✗ | ✓ Darkglass Suite ★ | ✗ |
| Ownership & Practicality | ||||
| Universal Voltage | ✓ 100–240V ★ | ✗ (region-specific) |
✓ 100–240V | ✓ 100–240V |
| Safe Without Speaker Load | ✓ ★ | ✓ | ✓ | ✓ |
| Aux / Backing Track Input | ✓ Via FX Return | ✓ 3.5mm Aux | ✓ 3.5mm Aux | ✓ Aux In |
| Fits Block Case 2.0 | ✓ | — | — | — |
| Patented Power Amp Technology | ✓ Quilter Q-Circuit ★ | Class D (G.I.V.E. preamp) |
Class D (Microtubes preamp) |
Class D (Subway preamp) |