A Tale of Two Three-Ways

Having the HEDD and ADAM ranges side-by-side allows us to make  interesting comparisons between their subtly differing designs. Clearly there’s a lot of shared DNA here: when ADAM hit a rough patch in 2014, two companies effectively continued development of the the product range: ADAM MD, physicist and R&D chief, Klaus Heinz, severed ties with the parent company and setup Heinz ElectroDynamic Designs (HEDD) while – armed with new funding from CWM Holdings, ADAM continues to evolve the classic A, F and S series models.

Really, though, that undersells the revolutionary nature of ADAM’s relaunched S Series: this is an entirely new speaker from – effectively – a new company with a new ethos. In early 2018, there’s a clear distinction between the old-school A-Series (including the A7X) and the fruitage of the CMW/ADAM era: namely the S and T models, including the S2V we’re here focusing on.

Heinz was at liberty to take the HEDD Type 07 in any direction he pleased. Evidently he felt the ADAM models developed under his watch weren’t far from ideal: on paper, the ADAM A7-X, HEDD Type 07 and ADAM S2-V have a strong family resemblance: all use folded diaphragm air motion transformer tweeters* with suprasonic frequency response. All HEDD models use proprietary UHC honeycomb composite woofers, clearly an evolution of the Kevlar/carbon fibre ‘Hexacone’ sandwich woofer in ADAM’s A7-X. New-school ADAMs showcase a divergently evolved variant of the Hexacone composite driver. All deploy some kind of switching amplification.

Cosmetically – as is fitting – the HEDD Type 07 announces its individuality with a tactile rubberised finish that smooths over outwardly visible seams and is practically grippy. The cabinet has small and large radiused edges and altogether the Type 07s feel expensive. The ADAM A7X by contrast is a no-frills black box: all sharp edges in wrapped MDF with those distinctive diagonal corner bevels. Combined with the shiny woofer, they clearly derive from a past era., whereas the S2V sets up a new classic look for ADAM: gracefully sculpted ports; gently curved edges and purposeful matt finish: as the retail price suggests, it’s built to a different price point – and it shows.

Although these speakers share a similar form factor (7-inch woofer + ‘ribbon’ tweeter), footprint (in the 220x350mm ballpark) and technology, only the cheaper models are direct competitors: the HEDD Type 07 at £549 per monitor is probably on the same shopping list as anyone looking at the A7X at £479. The ADAM S2V is £1549.

Listening impressions

HEDD Type 07 v ADAM A7-X

First up, there’s no avoiding the uncomfortable truth that the HEDD Type 07 is significantly more refined than the ADAM A7X, especially at the top end: HEDD’s AMT polishes all the grit out the A7X’s old X-Art tweeter: it’s a sensationally low-distortion driver that renders reverb tails and room ambience cues with effortless clarity. You can’t cheat your way to something that sounds this good. There are plenty of studio monitors that over-light treble to reveal detail but are fatiguing; ports kidd the listener speakers go lower than they do; hi-fi speakers have pushy midranges to accentuate vocals . . . the HEDD AMT (rather like the PSI tweeters) is the real deal: I can’t think of another top end close in this part of the market that’s competitive in terms of sophistication. The current Focal Shapes also have a superb tweeter but there’s a hint of clanginess about it that’s not present in the HEDD AMT. It’s properly groundbreaking at this price.

The extra £75 also buys you mo’ power: the A7X relies on a 75W PWM amp for woofer duty; the HEDD also opts for switching amplification (ICE) but is rated at 100W. The ADAM goes Class A/B for its tweeter, whereas the HEDD uses a second ICE module – also 100W – for HF. This adds up to an extra 2dB per pair advantage for the HEDD (116 v 114dB at 1m). ADAM rates the A7X to 42Hz ±3dB; HEDD quotes 38Hz within the same parameters. This is borne out in listening: the control and precision of the Type 07’s lower registers is next-level stuff. And it’s surprisingly hard to spot when the ports come into play.

People will still buy A7X because they’re A7X. A handful of people will prefer the continuity of an ADAM house sound they’re become accustomed to. And  there’s a reason why the classic A7X became a byword for accuracy at that price: it’s still great for picking apart a mix. If you’re really hair-shirted, you might even prefer it. But, so far, almost everyone we’ve auditioned them back-to-back with instantly chose the HEDD Type 07 over the A7X. It’s not only better to work with, it’s much nicer to listen to. You could put them either side of the TV or on the desk at home, and they would never sound uncouth, strident or less than awesome. They’re peerless at this price.

HEDD Type 07 v ADAM S2V

It says something that this is even a thing: comparing a £549 monitor with a £1549 monitor and finding that the HEDD isn’t hopeless outgunned against ADAM’s pocket battleship. But, yes, the HEDD is that good.

OK, so let’s inject a note of realism here: the ADAM S2V kicks ass like a donkey. It packs 350W per channel into its dense little cabinet and there’s nothing short of the top Genelec Ones at double the price that delivers full scale performance from such a compact box. And the superlatives don’t end there: like the Genelec SAM range, the ADAM S2V is a fully digital creature: that £1000 difference doesn’t just buy you more power (120dB per pair), it buys you full on-board DSP and a host of other tricks, including app control.

ADAMs have a peculiar affinity for mixing electronic music, and the S2V takes everything the A7X and A77X do well and moves it up another level. It’s particularly worth noting that HEDD aren’t the only ones to have refined the X-Art tweeter: the latest ADAM S-Art is a similar step forward in terms of refinement and  low distortion: sounding smoother and cleaner. Overall, I’d say the improvement from the old S-Series (S2A) to the new S2V is greater than the jump from the A7X to the S2A.

The S2V manifests its digital nature with the presence of AES/EBU inputs and outputs, and you really should use them. All inputs (analog and digital) funnel into the new DSP engine and crossover, but the AES input bypasses the additional A-D stage required to convert the analog XLR inputs – and it shows. The S2Vs come alive when fed digitally – and they show clear differences between AES cables and source clocks.

Comparing top-to-bottom response of these divergently priced monitors, the S2V’s top end is only a little more transparent than the HEDD Type 07 when run digitally, and comparable with analog input. Unlike many ‘ribbon’ tweeters, they’re both very civilised: the tonality of the HEDD AMT in particular could be mistaken for a soft-dome. If you’ve heard and not liked ribbons in the past, either of these will make you think again. Both have new, wide dispersion waveguides that greatly improve the size of their phantom centres. Near-field imaging is pretty similar. ADAM rate the low end of the S2V down to a frankly scary 35Hz, and they’re not mucking about – but what’s impressive about the S2V’s bass is that it’s not always drawing attention to itself in the way (for instance) the Focal Solo and Trio have a tendency to do.  It’s plucks low notes from a mix you don’t think it will reach. It’s able to pootle along in a understated way until you turn up the wick and unleash hell. The S2V is a heck of a lot more fun than the Type 07, but – again – bear in mind the price difference. The HEDD is no slouch, and mid-range performance (within the Type 07’s smaller envelope, at lower SPLs) is comparable. Neither have the pristine mid separation of their three-way siblings, but they’re both state of the art for two-way designs.

EQ/DSP/Digital compatibility

The A7X and Type 07 have familiar bare-bones EQ control. The A7X has that helpful power switch and volume control on the front panel, sadly omitted from the newer S2V and HEDD 07 whose controls all live on the back.

HEDD’s Bridge system consists of an expansion slot at the rear of each monitor permitting each pair to be enabled as Dante, Ravenna or bluetooth devices. Alternatively there are AES/SPDIF input options. With the Dante Bridge we’ve run a pair of HEDD Type 07 with nothing more than a laptop and a crossed network cable in dem: it works perfectly. However, it’s possible to improve on the sonic performance of the Bridge’s 24/96 D-A converter with a really top notch external interface or DAC.

There will be a separate article exploring the S-Series control app and DSP functionality, but I can offer a brief takeaway based on customer auditions so far: almost everyone prefers the unmolested ‘Pure’ option to the tailored EQ profiles. Full 6-band parametric EQ is available that does wonders to adjust S2Vs for well-behaved in-room response. It’s important to emphasise that because its XO is in the digital domain, use of the EQ is, practically, not lossy – not as lossy as its onboard A-D, anyway! The S2V cries out to be driven digitally and if you go even basic correction for desk mounting or room modes it will give more truthful in-room performance than any uncorrected speaker. Settings are locked into each speaker individually, which is essential when dialing out peculiarities of asymmetrical in-room placement.


Though nowhere near as well known yet as the parent brand ADAM, HEDD is a legitimate parallel evolution of its success. Where they go head-to-head (as in the HEDD Type 30 v ADAM S3H) it’s a very interesting story (coming soon). Here, though, we see progress clearly trumping old tech: the HEDD Type 07 is a new benchmark at around £1000 pair: it’s hard to overstate what a bombshell it is – let me know anytime you want to audition the classic A7X against it. Equally, though, the ADAM S2V is an exciting story: it offers a new level of big-box performance in a tiny package, full digital control, and a HEDD-level refinement that should win converts among people who don’t think they like ribbons, and also give brand-loyal upgraders something to get excited about.

* For background on Klaus Heinz’ collaboration with Oskar Heil in the 1980s on AMTs, see here . . .

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