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Hendy Amps Michelangelo

Stereo Valve EQ By Eric James
Published February 2020

Hendy Amps Michelangelo

Offering both controllable coloration and three interactive bands of EQ, the Michelangelo aims to deliver something a little different.

My analogue mastering chain, which comprises two equalisers and two compressors, has remained the same for seven or eight years. I know it so well that using it has become instinctive, and have thus been reluctant to change it; I've only done so when I've discovered something I felt I could not live without — at which point I swapped out an old processor for the new one, without extending the chain. By coincidence, the last two such changes were both to units that I initially explored for an SOS review: the Thermionic Culture Pullet ( and the Knif Soma (, and both are passive, but otherwise very different, EQs.

Because of this domestic bliss, the last thing I thought I'd be interested in acquiring would be a new EQ. Such an addition would have to bring something to the party that my broad, passive EQs haven't already. So what initially piqued my interest in the Hendy Amps Michelangelo — a broadband analogue EQ — was not only hearing good things about it on the mastering grapevine, but specifically hearing about it from fellow Knif enthusiasts.


The Michelangelo is a three-band (or arguably four-band, depending on how you count them), Class-A, all-valve EQ, with Jensen transformers. It has a number of unique features, the most immediately noticeable being the massive transformer, which sticks out of the back panel, and the next being the complete lack of frequency and bandwidth information on the front, other than for a lone two-way switch labelled 'Low Shift 80Hz-150Hz'.

The front panel contains six chicken–head rotary controls (Aggression, Low, Mid, High, Air and Trim) and various switches. Like the Low band, the Mid and High ones have a 'Shift' setting, with the options being 'flat' or 'full' for the former, and 'smooth' or 'sharp' for the latter. The Air band also has a two-position 'Shift' switch, the choice being simply on/off. A Vintage switch (on/off) can produce a darker sound. There are also true Bypass, post-processing Trim and Calibration controls. The last is used for balancing the channels and, in conjunction with the Trim control (Calibration up/Trim down), provides a means of increasing the harmonic content of the signal. Additionally, there's a ground-lift facility and, finally, a HiZ/LoZ switch, which changes both the sound of the Michelangelo and the interactions between it and other equipment. My preference, generally, was to use only the LoZ setting, which results in the least interaction.

Each unit is handmade to order by Chris Hendy, which makes further description of the unit's appearance a bit hazardous; there are a fair number of colour combinations on offer, and a couple of scale options too. The review unit came in the red, white and black livery of UK distributors SX Pro, with scale markings running from 0 to 10, but I gather there's an alternative scale marked 0 to 100. The review unit came with full-scale pots, but third-scale and switched options (perhaps better for mastering) are also available.

The provision of vague qualitative labels instead of firm quantitative information on the controls is in keeping with the overall vibe of the Michelangelo, and those who are used to working with clearer, more traditional parameters may have a hard time adjusting. I'm a great believer in applying broad strokes for most aspects of EQ (indeed, passive designs can't offer anything else) but even I had difficulty settling in at first. I'm really not sure what a newcomer used to dialling in decimal places for centre frequencies would make of it.

The bands are also interactive to a certain extent, and their response varies according to input gain, with low gain yielding a more transparent result. But at least this much can be said: the Aggression control (labelled 'Mojo' on some builds) increases valve saturation in a controllable way; the Low band is a shelf; the Mid is a single, very broad band, whose upper and lower limits are set by the Low and High bands and whose width and character are dependent on their settings; and the High is another shelf, as is the Air, which overlaps with it. The 'Shift' switch for each band alters its response, but apart from the aforementioned 80-150 Hz for the Low, and the information in the manual that the High and Air Shifts move their respective ranges by 1kHz, there's little technical information supplied. That said, the manual does also tell us that "High Shift changes the curve of the High shelf," and "Air Shift changes the curve of the Air shelf."

As we'll see, this lack of information is intentional — after a while, and a willed changed in perspective, none of it really matters, and from that perspective such concerns will seem churlish.

The front panel is, by design, almost devoid of any technical information — the idea being that the user must listen to the results and the way in which the different controls interact.The front panel is, by design, almost devoid of any technical information — the idea being that the user must listen to the results and the way in which the different controls interact.

In Use

My experiences of the Michelangelo passed through a slow and irregular learning curve. I was forewarned in email conversations with Chris Hendy that it would probably be useful to think of this EQ as more of a musical than a precision instrument — at one point he also said that, "It is an interactive beast that should be treated closer to a living being than a machine." So I knew that it wouldn't immediately slot into my regular workflow. Largely, that's because I don't make any processing decisions while at the desk. Instead, the monitors face my listening seat and my desk is a few feet behind that, arranged so that inputs to my eyes and my ears are completely dissociated. I've mastered like this for well over a decade, and find that it works extremely well, but it's clearly not suitable for the way of working Chris had suggested for the Michelangelo.

Luckily, I'm a great believer in the use of broad EQ in mastering, so to begin with I decided to explore and then to exploit what analogies I could find with my current arsenal of broad tone-shapers, and then to experiment from there.

I chose to start with the Maselec MLA-3; even if the two EQ designs couldn't be more different, when used as a three-band EQ the Maselec offers the most obvious functional analogy. The clean, solid-state MLA-3 has gain controls for each band, its Mid band is also bounded by the setting of the Low and High bands, and sometimes adding just half a decibel or so (with no compressor action) can be a way of bringing a little life to a track. So I tried this with the Michelangelo and was immediately impressed: leaving the Aggression at its most placid setting, just a nudge towards the next marker was like the MLA gain, but with a mild but definite burr in the voice from the tubes and transformers. I was likewise impressed with smidges of the other bands too. Choosing a slightly muddy mess of a track, I tried a small cut with the Low band, and then a small cut with the Mid shifted to cover the lower range, and both worked very nicely, as did the High. Similar comparisons were made for the lower Low and the Air band using the Soma and the Pullet.

Armed with a better sense of how to translate my processing decisions to the Michelangelo, I started on some real test material. I didn't use the Michelangelo on a final production master, since this was a loan unit and I'd need the ability to recall settings for my commercial projects, but I did use the same projects as my test guinea pigs. These included a jazz organ trio, a TV score with strings, a classical vocal recital, a balls-to-the-wall blues album, some EDM, and two lovely but very different electronica projects.

I began with the Michelangelo as the only analogue EQ in the chain (preceded where necessary with a pre-D-A 'corrective' digital EQ) and experimented with only one band at a time; I reasoned that I needed to learn their individual characters before diving into the more complex investigation of how they behaved in company. I started with just the Mid and experimented with its Shift, and quickly became even more fond of the way a tiny amount of boost could open up a sound stage and bring out detail from slightly 'closed' mixes, and how (with the Shift to the lower end) a tiny cut could do the same with mixes muddied by low-mid resonances. I then introduced the High band and learned a bit more about that (both on its own and then in partnership with the Mid) and then, in turn, the Low. The final stage was to add some Aggression to these experiments, to see what goodies it might bring to the party.

My expectations were often wide of the mark! Some were spot on, because they were obvious — I didn't find anything particularly useful that the Michelangelo could do for the classical vocal recital, and I found it simply wonderful for the blues album (magic for both guitar and voice). But I'd assumed both that I wouldn't like it much for the TV soundtrack, and that the jazz organ project (a serious Hammond) would lap it up... and in both cases I was wrong. The Michelangelo helped the soundtrack's sampled strings to soar a little more, and connected them with the rest of the arrangement; but on the jazz project, while the Mid did its expanding-the-sound-stage thing nicely, it got in the way of the B‑3 growl in a manner that the Knif Soma didn't on the final master.

Around the back, a large protruding transformer dominates the rear panel.Around the back, a large protruding transformer dominates the rear panel.

In general, I felt that the Michelangelo Low end, especially when shifted to 150Hz, had a texture — slightly dirty — that sounded appropriately and addictively huge for electric bass and low drums, but which didn't play so well when greater clarity was required (as with the acoustic jazz bass and some electronica low end, where harmonic or timbral accuracy was essential). I suspect the transformers might be more responsible for this characteristic than the tubes: in my past experience of compressors, I found the same issue with the Thermionic Culture Mastering Phoenix, but not with the Knif Vari Mu, which sports Lundahl amorphous-core transformers.

I'd assumed that I wouldn't like it much for the TV soundtrack, and that the jazz organ project (a serious Hammond) would lap it up, and in both cases I was proved wrong.

A possible downside I discovered in the Michelangelo was brought home when I lent the unit to my tech assistant to try out in his project studio over a weekend, with the aim of getting a different perspective to my purely mastering use. He was enthusiastic and texted a few times telling me how amazing the Michelangelo sounded on his mix bus. I was looking forward to hearing the results when he brought the unit and a handful of mixes to my mastering studio the next week. He explained how easy he'd found it to dial in some gorgeous tones, and how difficult it was to make it sound bad. As soon as we put the mixes up onto the mastering monitors, though, he realised that in his enthusiasm for the Hendy's sound, he'd overcooked things. I'd made my changes in fragments of a single marker, but he'd made his in terms of whole and half numbers, had mostly boosted, and had used the Aggression control freely (whereas in nearly all of my use I had left it off).

This isn't an unusual scenario to encounter in mastering. His smaller monitors just hadn't been able to warn him of the dangers, and the whole point of the second pair of ears and the high-res monitoring of a pro mastering house is to identify and deal with such issues. Yet I found that the mixes he'd overcooked with the Michelangelo were resistant to my usual corrective measures. If I'm sent a mix where the low end below 60Hz or so has more energy than the rest of the mix I can use EQ to correct it, and likewise with 'tizzy' mixes. But these mixes' issues had a more complex cause, and so seemed to require a more complex set of repairs. The 'take home' point here is that while the Michelangelo could indeed work really well on a mix bus, you need to be a little careful not to overdo it — being able to hear exactly what the Michelangelo is doing is a prerequisite to fully exploiting its potential, rather than abusing it.

Lasting Impressions

The Michelangelo, then, undoubtedly provides an extra dimension of harmonic colour, and for that alone it will appeal to many people in a range of applications, from adding colour to individual sources, to group- and mix-bus processing and, of course, mastering. However, I've read reviews that stress the 'colour' aspect of the Michelangelo too much. Yes, it can impart a unique coloration, which can work beautifully with some material and less well on others. But with the Aggression set to 0, the Michelangelo can also be relatively clean. I didn't personally find the need for its extra colour in my mastering work all that often, and I had its cleaner settings already covered in my chain. So in my pro work between the review tests I didn't often find myself really wishing that I could use it.

I found that it wasn't possible to write the usual detailed sort of review of the Michelangelo that I would for many EQs, for the same reasons that the manual has to be vague about its operations. There are too many ways of using it, not only in the ways you would use a regular EQ, but also counterintuitive ways in which the controls can be set 'against' each other. This is Chris's description of one such approach: "Create contradictory settings... turn on Vintage mode, which really darkens the mix but changes the High and Air response... then, when you bring the High and Air controls back up, they will have a different bite to them."

No EQ is going to be a one-stop shop, and I'm sure that the Michelangelo has deeper resources than I was able to find during its relatively short time in my studio. I go through this process of acclimatisation and exploration with every new link in my chain as it's introduced, but because of its apparently capricious nature, I get a strong feeling that I still don't know this one very well. While the Michelangelo is unlike most other EQs, it is familiar enough to give you something to start with — but getting to the point of using it with confidence will probably take a couple of weeks.

Analogue Heat?

The Michelangelo runs fairly hot and thus uses valves relatively quickly. Chris Hendy says he expects them to last, on average, up to two years with regular use. Sensibly, then, the unit has been designed to perform well using pretty inexpensive modern valves — it needs three 12AX7 (ECC83) valves, and the street price for, say, JJ Tesla versions of those is about £30$40 for a set.


  • Unique sound.
  • Unique flexibility of tone.
  • Simple operation (main choice is boost or cut) even if there's a long learning curve.


  • Requires high-quality monitoring.


A unique, interesting and high-quality stereo EQ with interactive bands, the Michelangelo is capable of a range of clean and coloured characters.


£2999 including VAT.

SX Pro +44 (0)1462 414 196

From $2650, depending on options specified.