Every guitarist who has ever hauled a twin-speaker Vox AC30 up three flights of stairs has had the same thought at roughly the second-floor landing: what if they made this thing 7 kilograms lighter? That thought finally became a product in June 2018, when Vox announced the AC30S1 OneTwelve at Summer NAMM. Single channel. Single 12-inch speaker. Four EL84 power tubes. Thirty watts. Same Top Boost circuit the 1960s were built on, wrapped in the familiar black basketweave and brown diamond grille cloth — and 7.7 kilograms lighter than the AC30C2 it sits beneath.
The S1 is not a compromise amp or a watered-down entry point into the AC30 world. It is a deliberate act of subtraction: strip away the Normal channel, the spring reverb, the Tone Cut, the tremolo, the second speaker, and the second footswitch socket — and what you have left is the one channel that built the sound of British rock. If you have always wanted an AC30 but live in a third-floor flat or a van without a trailer hitch, the AC30S1 was designed specifically for you.
Summer NAMM 2018: A 60th Birthday Present with Four EL84s
Vox turned 60 in 2018, and the brand marked the occasion with a run of anniversary announcements. The AC30S1 was among the most practically motivated of them. The thinking was transparent: the AC30C2’s dual-12 cabinet has always been the most authentic way to access the Top Boost sound, but it weighs 32.2 kilograms and demands a wide car boot or a willing roadie. Players who primarily use the Top Boost channel — which, in honest practice, is most AC30 players — were paying for a Normal channel they rarely touched, a spring reverb pan they occasionally rattled, a tremolo they turned off during soundcheck, and a second speaker they mainly appreciated for its cosmetic symmetry.
The AC30S1’s proposition is simple: if you’re only going to use one channel, buy an amp that only has one channel and spend the saved weight allowance on getting there intact. The cabinet is fractionally narrower — 658mm vs 702mm — and 7.7 kilograms lighter at 24.5kg. For a gigging musician navigating a city without parking, that is not a marginal gain.
The full story of how the AC30 came to exist in the first place — Dick Denney’s design work at Jennings Musical Industries in Dartford, the 1957 AC15, the push from Hank Marvin and The Shadows that produced the twin-speaker AC30/4 Twin in 1959, the introduction of the Top Boost circuit in mid-1961 (derived from the Gibson GA-77), and Korg’s 1992 acquisition — is covered in detail in the Vox AC30C2 article. The AC30S1 inherits all of that history. This article focuses on what the single-speaker model does differently, and whether it does it well.
Circuit: The Top Boost Channel, Unaccompanied
The AC30S1 uses a two-stage preamp built around two 12AX7 tubes, feeding into four EL84 power tubes running in class-A. The channel is a direct implementation of the AC30’s Top Boost circuit: a Gain control sets the amount of preamp overdrive, then independent Bass and Treble tone controls shape the frequency content before the Master Volume determines how hard the power stage is driven. That is your entire control surface — Gain, Bass, Treble, Volume, and Reverb. There is nothing else on the front panel.
The absence of a Tone Cut is the most significant functional departure from the AC30C2. On the twin-speaker model, Tone Cut operates in the power stage to progressively darken the output without touching the gain structure — it is the reason Brian May can run his Normal channel at full volume and still control the overall brightness of the sound. On the AC30S1, you have Bass and Treble in the preamp only. If you want to darken the amp at high volumes, you reach for the Treble control, which does change the harmonic content slightly differently than Tone Cut would. For most Top Boost applications — jangle, bloom, classic rock overdrive — this distinction is academic. For the specific Brian May approach of maxing the Normal channel and managing brightness with Tone Cut, the AC30S1 is the wrong amp entirely (and Brian May does not use the Top Boost channel in any case, which we will return to in the Famous Players section).
The reverb is digital, not spring. This deserves a sentence because it surprises people expecting a mechanical pan: MusicRadar’s Nick Guppy, reviewing the amp at launch, noted that “this effect is excellent and matches many studio effect/plugins for quality, with a range that goes from natural background ambience to full-on cavern.” The digital implementation means the reverb is consistent, noiseless, and does not rattle when the amp is driven hard. It is a practical improvement over the spring unit for gigging purposes, even if it lacks the happy accidents that make spring reverb beloved in a studio context.
The effects loop is a series send/return arrangement on the rear panel, allowing integration of time-based effects after the preamp stage. There is no footswitch for the loop — MusicRadar flagged this as the only meaningful limitation — so inserting and removing an effect mid-song requires a manual bypass on your pedal. An external speaker output allows connection to an additional cabinet, effectively turning the AC30S1 into a compact head with its own monitoring speaker.
One feature unique to the S1 among AC30 variants is an energy-saving auto-power-off: the amp switches itself off if no audio signal is detected for approximately 15 minutes. There is a small switch to disable this if you prefer the tubes to warm up and stay warm, which is the sensible choice for a gigging session. The power switch itself is a momentary-action toggle operating a relay rather than a conventional mechanical switch. It feels slightly odd on first encounter but becomes unremarkable after one rehearsal.
The cabinet is semi-closed back — not fully open like some boutique single-speaker combos, not fully sealed. The semi-closed design balances bottom-end extension (which a fully open back would compress) against the slightly more focused, controlled low end of a sealed enclosure. MusicRadar noted this produces “plenty of volume and bottom end, with a slightly more focused treble when you listen on-axis compared to a 2×12 enclosure.” The practical takeaway: the AC30S1 does not sound thin or small; it sounds like an AC30 that has been narrowed in its stereo spread, which is what it is.
Specifications
| Parameter | AC30S1 Spec |
|---|---|
| Output Power | 30W RMS |
| Output Impedance | 16Ω |
| Power Tubes | 4× EL84 |
| Preamp Tubes | 2× 12AX7 |
| Speaker | 1× 12″ Celestion VX12 (custom-voiced) |
| Cabinet Type | Semi-closed back |
| Channel | Single — Top Boost |
| Controls | Gain, Volume (Master), Bass, Treble, Reverb |
| Inputs | 1× Normal Input, 1× FX Loop Return |
| Outputs | 1× External Speaker (16Ω), 1× FX Loop Send |
| Reverb | Digital (spring simulation) |
| Auto Power-Off | Yes (~15 min silence), switchable |
| Dimensions (W×D×H) | 658 × 265 × 550 mm / 25.91 × 10.43 × 21.65″ |
| Weight | 24.5 kg / 54.01 lbs |
| Made In | Vietnam |
| MPN | AC30S1 |
| Price New | $999.99 (Sweetwater, 2026) |
| Used Price | From ~$449 (Reverb, 2026) |
| Announced | Summer NAMM, June 2018 |
The Celestion VX12: Stock Speaker and the Upgrade Question
The AC30S1 ships with a Celestion VX12 — a speaker designed specifically for Vox and voiced to complement the Top Boost circuit in a single-speaker application. It is not the Alnico Blue that most people associate with the vintage AC30 sound, and it is not a G12M Greenback. It occupies a middle territory: more focused and articulate than the vintage-style Alnicos, with a controlled top end that prevents the single-speaker arrangement from sounding harsh when pushed.
The VX12 is not, by most accounts, a speaker worth preserving at all costs. Jake Snider of Minus the Bear — the single confirmed professional user of the AC30S1 on Equipboard — replaced his stock VX12 immediately, stating plainly: “And this is the new S1 AC30, just a single-speaker top boost channel, and I had a creamback put in it instead of the stock.” The Celestion Creamback (G12M-65 or H75, depending on the variant) is the most popular first-swap choice: it adds warmth and midrange texture that the VX12 doesn’t quite achieve. Alnico Blue swaps are also common but the Blue’s 15W rating is technically below the AC30S1’s 30W output — this is fine at bedroom levels and cautious gigging volumes, but driving the amp hard into an Alnico Blue is a documented path toward a blown speaker.
The speaker is accessible from the rear of the semi-closed cabinet. A standard 8Ω Celestion in a 16Ω cabinet impedance is the correct matching, and the external speaker output expands the options further: a second cabinet wired in parallel brings the total impedance to 8Ω, which the AC30S1’s 16Ω output jack will handle without complaint at the cost of a slight mismatch. Check with the specific cabs involved before wiring a parallel setup.
Famous Players: The Calendar Test and What It Reveals
The spreadsheet data for this article lists five artists: Brian May, The Edge, George Harrison, Tom Petty, and Rory Gallagher. All five are iconic AC30 players. None of them are documented as AC30S1 players. Three of them could not possibly be: the AC30S1 was announced in June 2018.
George Harrison died in November 2001. Rory Gallagher died in June 1995. Tom Petty died in October 2017 — eight months before the AC30S1 was announced at Summer NAMM 2018. The calendar eliminates three of five names before any additional research is required. This is the same pattern documented in the Rank 375 Gretsch G9200 article: for any post-2010 SKU, checking death and retirement dates against the model’s launch date is the cheapest possible falsification test.
The remaining two — Brian May and The Edge — are legitimate AC30 users who happen not to be documented on this particular model. Brian May‘s amplifier of record, from the first Queen album in 1972 through the mid-1970s, is the AC30 Normal channel (not Top Boost) driven with a Dallas Rangemaster treble booster, with the Master Volume low and the Tone Cut set between 8 and 9 to control brightness. The AC30S1 has no Normal channel and no Tone Cut, making it structurally the wrong amp for the specific Brian May sound — a point the article is frank about. Vox does manufacture a Brian May signature series (the MV50 Brian May, the MV50 BM mini head), but these are separate products from the AC30S1. The Edge, whose touring rig as documented in a Premier Guitar Rig Rundown includes two 1964 AC30TBs handwired by Dave Clarke and two 2016 production AC30s modified by Clarke, is similarly documented on vintage-spec AC30 variants and on the AC30C2 — not specifically on the single-speaker S1.
The one confirmed professional user of the AC30S1 on Equipboard is Jake Snider, lead vocalist and guitarist of Minus the Bear. Snider’s use of the S1 is documented with a direct quote — he specifies the model by name, discusses replacing the stock Celestion VX12 with a Creamback, and contextualises it within a single-channel setup philosophy. Minus the Bear’s blend of tapping-heavy indie rock and atmospheric textures sits naturally in the Top Boost wheelhouse: clean chime, touch-sensitive bloom when pushed, and enough headroom above the gain knob to let a delay pedal breathe in the effects loop.
Players who regularly work in the AC30 Top Boost universe — Jonny Greenwood, Ed O’Brien, Noel Gallagher, Paul Weller, Matthew Bellamy — all use or have used the twin-speaker models. The AC30S1 is not the amp that appears in their stage rigs precisely because the transport compromise is not one that riders and crew need to make at stadium scale. The S1 is a gigging musician’s amp, a touring-van amp, a pub-circuit amp. It gets you the same topology, the same tubes, the same channel, and most of the same sound at a weight that one person with decent shoulders can manage alone. That is its market.
Tone Recipes and Settings
Recipe 1: Classic 60s Jangle — The Shadows / Early Beatles
Guitar: Fender Stratocaster or Rickenbacker 360, bridge or middle pickup. Gain: 3. Bass: 5. Treble: 6. Master Volume: 4–5. Reverb: 4–5. Add a medium delay (300–400ms, two or three repeats) in the effects loop. Pick lightly with the tip of the pick, over the neck pickup. The slightly boxy mids MusicRadar noted in the VX12 at low gain are a feature here, not a flaw — they recreate the particular weight of those early 1960s BBC studio recordings. Hank Marvin’s approach: hold the trem arm with the little finger and let the pick rest approximately over the neck pickup for the characteristic plummy transient.
Recipe 2: Indie Rock Bloom — The Jake Snider / Minus the Bear Setting
Guitar: an Epiphone Casino-style semi-hollow or a Strat-type with single coils. Gain: 5–6. Bass: 6. Treble: 5. Master Volume: 6–7 (let the power stage contribute). Reverb: 2. Add a chorus or phaser in the effects loop with a long rate and moderate depth. Replace the stock VX12 with a Creamback if you have the budget and the inclination — the difference in midrange texture at this gain level is not subtle. The Top Boost’s touch-sensitive character means picking harder gives you articulate crunch; a soft pick delivers clean shimmer from the same settings.
Recipe 3: British Blues — B.B. King at the Marquee
Guitar: Gibson ES-335 or similar semi-hollow, neck pickup. Gain: 6–7. Bass: 7. Treble: 4. Master Volume: 6. Reverb: 1. The AC30S1 will not distort in the way a Marshall does — the EL84 compression is gentler, more consensual. What it gives at this setting is a singing sustain with a toothy attack that complements a slightly humbucker-heavy signal. A mild overdrive pedal — a Boss BD-2 Blues Driver or a Fulltone OCD — in front of the amp can push the tubes into a more committed bloom if the fully clean EL84 character reads as too polite for the gig.
Recipe 4: Power-Trio Rock — Edge of Breakup, Maximum Presence
Guitar: Telecaster bridge pickup, or a Les Paul with PAF-style humbuckers. Gain: 8–9. Bass: 5. Treble: 7. Master Volume: 4 (louder if the room allows). Reverb: 0. A Pro Co RAT or a EHX Big Muff Pi before the input will push the preamp further than the onboard Gain control alone can manage. At these settings MusicRadar reported the amp coming “very close to classic Queen, with maybe a touch more gain needed for lower output pickups.” The lack of Tone Cut means you manage brightness entirely with the Treble control: roll back to 5 or 4 if the single-12 top end starts to read as harsh at stage volume.
Recipe 5: Spaghetti-Western Surf — Instrumental Cinema
Guitar: Fender Jazzmaster or Jaguar, bridge pickup. Gain: 4. Bass: 4. Treble: 5. Master Volume: 5. Reverb: 7–8 (near maximum). Add a tape-style delay in the effects loop with dotted-eighth timing — the Electro-Harmonix Deluxe Memory Man is the canonical choice, adding modulation that sits beautifully over the AC30’s harmonics. The VX12’s slightly controlled top end (relative to an Alnico Blue) prevents the reverb-heavy signal from becoming washy. Keep the picking hand light and let the notes sustain into the reverb tail.
How the AC30S1 Compares to its Siblings and Rivals
vs. Vox AC30C2 (Rank 454)
The AC30C2 is the full twin-speaker version with Normal and Top Boost channels, spring reverb, tremolo, Tone Cut, FX loop, two footswitch jacks, and 2× Celestion G12M Greenbacks. It weighs 32.2 kilograms and costs $1,799.99 new. The AC30S1 gives you the Top Boost channel only, digital reverb, FX loop (no footswitch), one Celestion VX12, and weighs 24.5 kilograms at $999.99. If you use both channels, need tremolo, or specifically want spring reverb and Tone Cut, the C2 is the correct amp. If you use Top Boost exclusively and carry your own gear, the S1 saves you $800 and 7.7 kilograms. That arithmetic is straightforward.
vs. Vox AC30 Top Boost (Vintage, Rank 381)
The vintage AC30 Top Boost from the JMI era (1961–1968) is a different proposition entirely. Hand-wired, UK-built, 2×12 with original Celestion Alnicos — and priced between $3,000 and $8,000+ on the used market depending on condition and year. The AC30S1 shares the circuit topology and the basic character, not the construction method, the materials, or the fifty-year playing-in. For working players who need a reliable, road-ready AC30 sound rather than a collectible, the S1 makes the comparison easy.
vs. Vox AC15C1 (Rank 398)
The AC15C1 is a 15-watt single-12 combo with two EL84 power tubes, also based on the Top Boost circuit, priced around $599. Half the power, half the tube count, slightly thinner at stage volume. The AC15C1 breaks up earlier and more dramatically — an asset for players who want pushed-tube breakup at rehearsal volumes. The AC30S1 has more headroom and stays cleaner longer, making it the better choice for Top Boost jangle at pub-gig volumes without edge-of-the-seat volume-knob management.
vs. Fender Blues Junior IV
The Fender Blues Junior IV is a 15-watt 1×12 tube combo around $699 new, using EL84 power tubes in a cathode-biased configuration that is closer to the Vox character than a blackface Fender. Its voicing is American rather than British — more prominent low end, a scooped mid, a glassier top. The Blues Junior breaks up earlier and sounds great pushed, but doesn’t do the Top Boost chime. If you play blues and classic rock and don’t specifically need the AC30 frequency signature, the Blues Junior is $300 cheaper and four kilograms lighter. If you need the chime, there is no substitute.
vs. Fender Blues Deluxe Reissue
The Fender Blues Deluxe Reissue is a 40-watt 1×12 combo with a 12AX7/6L6 front end and a single Eminence speaker, around $799–$999 new. The 6L6 power tubes produce a distinctly American sound — wider dynamic range, more prominent low-frequency extension, a different distortion character (more odd-order, more aggressive) compared to the EL84’s even-order warmth. The Blues Deluxe is the better amp if you play country, blues, or Americana and want clean headroom to high volumes. It will not produce the Top Boost British chime at any setting.
Buying Guide
The AC30S1 is an in-production amplifier with broad retail availability. New pricing at US retailers is $999.99 (Sweetwater, zZounds, Guitar Center) as of mid-2026. Used examples appear on Reverb from approximately $449 upward; a VX12-equipped example with cosmetic wear but functional electronics typically fetches $550–$700. Units with a speaker upgrade already installed — Creamback, Alnico Blue, or Vintage 30 — tend to move at a small premium and are worth seeking out if you plan to swap the speaker anyway.
Before buying used, confirm: (1) all four EL84 power tubes are functional and balanced — a weak tube will cause hum and uneven response; (2) the digital reverb works across its full range, since the reverb board is a separate daughter PCB and a faulty unit is a specific repair rather than a general electronics problem; (3) the auto-power-off disable switch functions and the relay-operated power toggle responds cleanly; (4) the effects loop send and return are both operational — run a cable in the loop and confirm signal passes cleanly without noise. Structural cosmetic wear on the basketweave vinyl is expected and irrelevant to tone, but check the grill cloth is not covering a torn speaker cone.
The AC30S1 suits players who: primarily use a single overdrive-to-clean channel; value portability in a gigging context; work in indie rock, alternative, country, classic rock, or blues; and want genuine tube tone without the complexity of a multi-channel switching amp. It is not the right amp for players who need high gain, multiple channels, tremolo in the amp, a spring reverb pan for mechanical reverb sounds, or a second footswitch socket. Those players should look at the AC30C2 or the AC30C2X.
Ownership Notes
Volume reality: 30 watts of class-A EL84 power through a 12-inch speaker is louder than the specification suggests. At Stage Volume 6, the AC30S1 comfortably fills a pub room. In a small apartment, Stage Volume 2–3 is domestic tolerance. A power attenuator — a Boss Waza Tube Amp Expander, a Fryette Power Station, or a Two Notes Torpedo Captor — is the pragmatic solution for home players who want the tubes warm and contributing without calling the police. The attenuator is not included in the $999.99 price and is not cheap; factor it into your budget if home practice is a primary use case.
Tube maintenance: Four EL84 power tubes in cathode bias do not require periodic re-biasing in the way fixed-bias amps do. When tubes age, the symptoms are typically increased noise, reduced headroom, and uneven channel response. A matched quad from a Vox-approved supplier (or any quality tube vendor’s EL84 matched set) runs $40–$80 and is a DIY job on most AC30 variants — the AC30S1’s semi-closed back means the power tubes are not as easily accessible as on a fully open-back combo, but a screwdriver and a small torch are the only tools required. Two 12AX7 preamp tubes are even simpler to swap and rarely need replacement within five to ten years of regular use.
Speaker access and swap: The semi-closed back panel is removed with a Phillips screwdriver. Standard speaker fitment is a 12-inch driver in a 16Ω impedance. An Alnico Blue will fit dimensionally but its 15W rating is a documented mismatch risk at high power-stage drive. The Celestion Creamback (G12M-65 Creamback, 16Ω, 65W) is the most frequently recommended replacement: it maintains the articulate top end of the VX12 while adding warmth and midrange body. The Celestion Gold (50W, Alnico, 16Ω) is a premium option that delivers the vintage Alnico character at a safer wattage rating than the Blue. Vintage 30 (60W, 16Ω) swaps are popular with players who run the amp into higher gain territory — the V30’s pronounced upper-midrange complements a boosted signal where the VX12 can read as slightly polite.
The auto-power-off switch: Turn the auto-off feature off before a gig or session where you expect extended pauses between segments. A tube amp that silently shuts down mid-set and requires a two-minute warm-up cycle to restore is a practical problem that belongs in rehearsal, not on stage. The switch is on the rear panel and clearly labelled.
Effects loop use: The series effects loop is pre-volume-stage in the AC30S1’s signal path. Time-based effects — delay, reverb, chorus — belong in the loop after the preamp distortion; putting them before the input works but feeds the effected signal into the gain stage, which changes the character of both the effect and the distortion. Fuzz and overdrive pedals are generally better placed before the input, since they interact with the input impedance and the preamp’s gain structure in the intended way.
External speaker output: The external speaker jack is rated at 16Ω. Connecting a second cabinet in parallel halves the load to 8Ω, which is technically a mismatch with the output transformer but within the tolerance range most tube output stages handle without damage. For extended use with a second cabinet, verify the total impedance and consider consulting the Vox service manual or a qualified amp technician.
Frequently Asked Questions
What is the difference between the Vox AC30S1 and the AC30C2?
The AC30C2 has two channels (Normal and Top Boost), spring reverb, tremolo, Tone Cut control, 2× Celestion G12M Greenback speakers, and weighs 32.2 kilograms. The AC30S1 has a single Top Boost channel, digital reverb (no spring), no tremolo, no Tone Cut, 1× Celestion VX12, and weighs 24.5 kilograms. Both use four EL84 power tubes and two 12AX7 preamp tubes for 30 watts of class-A output. The AC30S1 costs $800 less new and is substantially easier to transport.
Does the AC30S1 have spring reverb?
No. The reverb is digital, simulating a spring reverb unit. MusicRadar’s 2018 review rated it highly — “excellent and matches many studio effect/plugins for quality” — but it is not a mechanical spring pan. If you specifically need spring reverb character (including the physical rattle when the amp is bumped), the AC30C2 with its spring unit is the correct choice. For consistent, noiseless reverb in a gigging context, the digital implementation on the S1 is the more practical option.
Who are the famous players documented on the Vox AC30S1?
The only confirmed professional user documented on Equipboard as of mid-2026 is Jake Snider of Minus the Bear, who has stated in his own words that he uses the AC30S1 with a Celestion Creamback replacing the stock VX12. Artists commonly associated with the AC30 family (The Edge, Brian May, George Harrison, Rory Gallagher, Tom Petty) are not documented on this specific model. George Harrison, Rory Gallagher, and Tom Petty all died before the AC30S1 was announced in June 2018, making their association with it factually impossible.
Can I swap the speaker for an Alnico Blue?
Physically yes, electrically risky. The Celestion Alnico Blue has a 15W power rating; the AC30S1 delivers 30W. At low to moderate volumes the mismatch is safe. Driving the amp hard — particularly at high Gain and Volume settings — risks exceeding the Blue’s thermal limit. The safer Alnico option is the Celestion Gold (50W, 16Ω), which delivers the vintage Alnico character with a wattage rating that allows full-power use. The Creamback (65W, 16Ω) is the most commonly recommended everyday replacement.
Is the AC30S1 loud enough for band rehearsal?
Yes, comfortably. Thirty watts of class-A EL84 output through a 12-inch speaker produces a perceived loudness comparable to a 50-watt fixed-bias amp. In a rehearsal room with a kit drummer, Stage Volume 5–6 is generally sufficient for guitar-to-drums balance without ear protection concerns. On small venues and club stages, Volume 4–5 with a PA feed on the front-of-house mix is the standard approach.
Does the AC30S1 have a footswitch?
The AC30S1 does not have a footswitch socket and is not compatible with the VFS2A footswitch used with the AC30C2. Since there is only one channel, there is nothing to switch between. The reverb and the effects loop cannot be bypassed by footswitch on the S1; to remove the reverb mid-song, you turn the Reverb knob down. This is the accepted workflow tradeoff for a simplified, single-channel amp.
What does “class-A” mean in the context of EL84 tubes?
In class-A operation, all four EL84 power tubes conduct current throughout the entire audio signal cycle — none of them switch off at any point in the waveform. This produces predominantly even-order harmonic distortion (second and fourth harmonic) when the tubes are pushed, which the human ear perceives as warm and musical rather than harsh. Class-A also means the tubes run hot and consume more power than class-AB designs (where pairs of tubes share the load by switching on and off alternately). The warmth of the AC30 sound, its smooth compression, and its particular response to pick attack are all characteristics of the class-A EL84 configuration.
How does the AC30S1 sound at bedroom volumes?
Acceptable but not optimal. At very low volumes — Stage Volume 1–2 — the AC30S1 sounds clean and relatively thin, because the power stage is barely working and the speaker hasn’t reached its working temperature or excursion range. The Top Boost character reveals itself most clearly at Volume 5 and above. For home use, a power attenuator is the recommended solution: it lets you set the amp at an appropriate operating point and then reduce the speaker level independently, preserving the power-stage contribution while keeping the domestic noise at a manageable level.