Pre/Power Amplifiers

It’s taken long enough but Quad has finally revived one of the best-selling pre/power amp combinations of all time. Between 1967 and 1982, 120,000 Quad 33 ‘control units’ were sold, while the 303 power amplifier remained in production until 1985 to reach 94,000 sales. So these new Quad 33 and 303 models have big shoes to fill, but retaining the original model designations and dimensions are a start. And that’s pretty much where the resemblance stops. Welcome to the 21st century.

Anyone who knows the originals will instantly recognise the look, which – as with the Thorens TD 124 DD [HFN Jul ’21] and other revisited components – is crucial if the 33/303 is to exploit all that nostalgia promises. But Quad has been brave, avoiding ‘exact replica’ visuals. Instead, the 33 and 303 have undergone updating outside and in. For my money, the aesthetic renewal is as successful and crafty as that of the current Mini – familiar yet completely fresh. What’s so remarkable are the prices at just £1199 per unit.

Cashing out

Go back to 1967 and a 33/303 system sold for £98, equal to £2230 today. Add 20% VAT and the new combo costs over £400 less in real terms. And what you get is wa-a-ay more on every level. Just about the only thing which hasn’t changed is the circa-50W/8ohm power rating.

First was the look: I simply could not resist placing the new set alongside the old. Initially, I thought the reimagined versions would be larger, but no: the new 33 occupies 258x83x165mm (whd) against the original’s 258x83x150mm, differing by a mere 15mm in depth. As for the revived 303, it’s the same width and depth as before, only 11mm taller. Visually, they’re exactly how one would imagine the 33/303 might have evolved had they never ceased production.

Above: Touch the illuminated button to bring the 303 out of standby. The alloy case design, with its front-facing heatsinks, ensures the amplifier never gets beyond merely warm in normal use

As evinced by the 33’s back panel, modernisation includes not just MM/MC phono and three RCA line-level inputs, but a balanced XLR input as well – bye-bye DIN sockets. This is quite an achievement in such a small space, fitting maximum inputs in minimal real estate. That said, compactness was the 33’s greatest trend-setting move nearly 60 years ago. Quad has wisely ignored only one modern element in updating its preamplifier: no onboard DAC. And that’s a good thing, as most digital products have the shelf-life of a banana.

Outputs, too, have been dragged into the 2020s. In addition to Pre and Auxiliary RCA outputs, there’s a pair of XLRs for balanced operation. Also on the back of the 33 are 12V in/out triggers so you can switch on the 303 at the same time, as well as a main on/off rocker and a phono earthing post. Lastly, there’s a USB-A socket for firmware updates.

Go with the glow

Hearts will swell for many of you upon first seeing the 33’s fascia, like Edmond Dantès returning home after exile. A motorised rotary ALPS volume control dominates the left side, while the right has three flush rotaries for balance and the signature variable tone controls. Quad has kept these even though tone controls fell out of favour around the time the 33/303 ended production. They work as before [see PM's Lab Report], with far more restraint than conventional bass/treble controls, while the display makes them more useful thanks to numerical read-outs.

Above: Custom toroidal transformer [bottom] supplies the main PSU [top] for the 303’s input [far right] and two-transistor complementary output stage on back of heatsink [left

Ah, the display! Proving that ‘orange is the new blue’, it perfectly matches the lighting on MoFi’s MasterPhono [HFN Dec ’23] – the display glows like a Jaffa, as do the eight push-buttons. These handle selection of the three ‘aux’ inputs and XLR on the left, while the quartet to the right deal with phono, tone defeat, display on/off and standby. When the 33’s main power is switched on at the back, the standby button glows softly. Press it to turn on the unit and the illumination increases. The same applies to each press button when activated.

Every function is available via the preamp’s remote control, so trying out the tone controls, for example, is possible from the listening position. Repeated pressing on ‘Phono’ chooses between MM and MC, the latter with enough gain for even low-ish output MCs. The addition of a headphone socket is one more bonus not found on the original. It’s worth mentioning, too, that the build quality and finish of both the 33 and the 303 are exemplary, with the older units’ corners and the rounded edges of the power amplifier’s heatsinks having been sharpened to look more contemporary.

The 303 is one honey of a (circa) 50-watter. Two were supplied so we could test them in bridged form – this was not needed for my DeVore O/93s [HFN Mar ’23], but add a second one and it’s not just the available power that increases but also bass solidity, dynamic contrasts and speed.

As the 303 is so well-designed, you can probably undertake hook-up without checking the manual, but note that the legends can be difficult to see in certain lights. The colour scheme has changed from the original’s almost mud-hued grey to a titanium metallic, so white-on-silver lettering can challenge seniors like me. Otherwise, push-buttons choose between RCA and XLR balanced ingress on the 303, while the multi-way binding posts are clearly marked for stereo or bridged mono.

Brave new world
Forget everything you know about the sound of the original 33/303. I played old-and-new side-by-side, and while the 1960s pairing still sounds wonderfully warmer, it lacks the ultimate precision, bass control and extension at the frequency extremes. Consider what Peter Walker unleashed in 1967, and you accept that these were voiced first and foremost for the Quad 57 ESL – their most likely partner. The new 33/303 has to face a world of lower impedance if typically higher sensitivity speakers if they’re to succeed.

And, wow, do they ever! I tried speakers from 4-15ohm impedance and 85dB-93dB sensitivity and power was never an issue. Adding a second 303 changed not just the dynamics due to the added wattage, but audibly tightened up the lower registers. All remarks from here on, however, refer to a single 303 running in balanced mode, with the 33 in its tone-off position.

House music

Appropriately, my first taste came from a mono 1964 LP. The Animals’ eponymous debut [Parlophone 5021732442697] is, for many, preferred in that mode, ‘House Of The Rising Sun’ probably heard by more people over AM radio than off vinyl. Via the 33’s MC phono stage, the sound was crisp, with plenty of ‘twang’ on the guitars, while the two star elements – Alan Price’s Vox Continental organ and Eric Burdon’s achingly raw, inimitable vocals – were afforded a tactile presence I would expect of a pairing with a zero added to the price.

At the same time, I ran the matching CD [Parlophone 5021732442703] both to listen to a line input and to compare stereo vs mono; the CD offers both. As for the first, the resolution of the 33/303 system is enough to provide astute listeners with the information needed to compare analogue with digital, the latter still showing a mild but detectable artificial tint which manifests itself in a crispness or edginess that could run perilously close to sibilance. The vinyl does not.

Above: Switchmode PSU for standby [bottom] alongside MM/MC [right], motorised volume [top right] and logic housekeeping [top]

I also compared the 33’s phono stage with a state-of-the-art phono amp costing more than double the 33/303 combination. While it provided audibly superior transparency and cohesion, the 33’s phono section is easily worth the £500-£700 one would pay for a phono amp from MoFi or Pro-Ject, albeit without their desirable adjustability.

Glory days

Moving to stereo material, Quad’s reborn pre/power pairing exhibited a blessedly wide soundstage – and I repeat, with one 303, not a bridged pair. The stage depth was good if not astounding, but the width was enough to unleash the full scale of a Decca Gold cartridge as well as the glories of that show-off recording from 1958, Bob And Ray Throw A Stereo Spectacular [RCA CPS-199 open-reel tape].

To savour fully this early champion of stereophonic sound, one needs cavernous openness and scale, as the musical numbers share playing time with sound effects, eg, creaking castle doors, and comedy narration. Here the revitalised 33/303 reminded me most of the era of its progenitors, when soundtrack and stage recordings were among audiophiles’ favourite fodder, for these units sound ‘huge’ in the literal sense.

Above: Phono and four line ins (three on RCAs, one balanced on XLR) are joined by variable and fixed RCA, and XLR outputs. Trigger ports and a USB-A for updates were science fiction in 1967

If you really want to know how the new 33/303 manages the smoothness of the originals but with added detail, turn to best-recorded jazz of the era. Any of the recent Craft reissues will serve, such as Howard McGhee’s Maggie’s Back In Town [Craft CR00710] from 1961, with punchy brass and Leroy Vinnegar’s ‘walking bass’ as revealing as any test LP. This combination is hard to resist.

Made to match

This begged a question about the two as separates rather than as a pairing. Although most original 33s and 303s were purchased as packages, the 33 outsold the 303 as cited above, but why I do not know. As a reverse of that, I suspect the new 303 amplifier will outsell the 33 preamp, because of customers opting to bridge them. It’s also worth pointing out that the 33 is a perfect match sonically for the 303 (or two) and is just as much of a bargain, so the only reason for buying either but not both would be if one is replacing or upgrading just a preamp or power amp. Like the originals, the new amplifiers truly deserve each other.

Above: The original 303’s single stereo DIN input is replaced here by a choice of RCAs or balanced XLRs just as the 4mm speaker sockets have morphed into chunky 4mm binding posts. The new 303 may also be switched into bridged mono mode

Since the teaser images of the 33/303 appeared following 2024’s Munich High End Show, a significant quarter of the hi-fi community has been buzzing with anticipation. Those captivated by the promise of those photos won’t be disappointed. All I would ask of Quad, to make this return complete, is the creation in the 33 casework of a digital ‘control unit’ with SACD/DAC/streaming functionality, referencing the look of its FM3 tuner; its tuning scale is the ideal shape for a CD tray. Finish off with the double wooden sleeve and there will be no better use of the phrase, ‘Back To The Future’.

Hi-Fi News Verdict

We are awash with integrated amps or pre/power pairings under £2500, but the new Quad 33/303 stands out from the rest. Even deliberately ignoring my bias for retro, I was seduced by a listening experience as delightful as that of the original’s, with resultant night-long sessions. The 33/303 is a charmer, and Peter Walker would be proud. I am buying a set as my mid-priced reference. What more can I say?

Sound Quality: 89%