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Rycote’s first microphones – review and tests of the HC-15 and HC-22 shotgun mics

October 13, 2021

New microphone manufacturers appear from time-to-time, but when I heard that Rycote – with over 50 years of well-respected design and manufacturing of microphone windshields and suspensions – were producing their first microphones, this stood out as something rather different: both their reputation and experience with other mics suggested that this could be an intriguing addition to the market. Given Rycote’s long involvement with broadcast and film sound, it isn’t that surprising that the two mics are both shotguns: one 15cm long and the other 22cm, giving rise to the HC-15 and HC-22 names. The specs fueled my initial interest as did the fact that they are made entirely in the UK at Rycote’s factory in Stroud. The price is interesting too, with the HC-15 costing £560 and the HC-22 £575 (ex VAT). This places the mics in slightly underpopulated territory, well above the list prices for the Rode NTG5 and NTG3, but well below the list price of the Sanken CS1-E or, say, the Audio Technica BP4073. Many staples of location sound recordists – such as the various shotgun mics made by Sennheiser, Schoeps and DPA – are more costly still. So, intrigued by all this and knowing Rycote to be a friendly and approachable company (see, for example, their help with my oversized LDC mic windshield), I asked whether they would let me review and test the mics: a few email exchanges later, and the mics arrived last week – no conditions/obligations applied nor, indeed, any timescale for their return! They included some foamies and a Classic Softie kit, with a Nano Shield (out of stock) on its way soon.

The approach

I don’t know about you, but I’m not overly excited by mic reviews – usually vlogs – that involve unboxing and reiteration of the published specs, in this case readily available online on the Rycote website, along with some tests of the mics in an unlikely location (e.g. with shotgun mics locked off above a vlogger’s head in their indoor studio). Of course, there is a value in comparative tests of mics, despite the danger (for shotgun mics) of these ending up being grouped in static arrays, but the number of professional shotguns available means that this is outside the scope of what I can do: for the nuances of Mic A vs Mic B there is no substitute for testing and working with both mics yourself and no review or on-line test is going to replace that. Rather, the focus of this review is a series of more real-world tests with the two Rycote mics, some out and about on location, with the aim to see if the Rycote mics are contenders for serious use. Sometimes I use another mic for the purpose of comparison, or to illustrate a point, and mostly I use the HC-15 and HC-22 together – which at least helps clarify the differences between the two. Sometimes I use the HC-15 and HC-22 in combination with a fig 8, to see how they stand up is the mid mic in a mid-side stereo pair: common use for a shotgun mic. But you won’t find any tests of the mics mounted on a camera: I’ve yet to find a need for this, and my gut feeling for such use is the compromised positioning means a more modest shotgun (and perhaps one without P48) will do the job.

Rabbit rabbit

With dialogue or speech recording being key uses for a shotgun mic, I was keen to put the Rycote mics through their paces on voices. There are many different aspects to this, but the ones I was keen to test were overall sound (Rycote describe their mics as ‘precise’ and as having ‘a crisp sound with some additional warmth’) and off-axis response (how coloured is the sound off-axis?).

For this test, I went to a small local theatre (the Sheringham Little Theatre) to use its stage: not a huge sound-treated stage, but a step up from a village hall, and did some tests with the writer (Chris Sainton-Clark) reading excerpts from his one-act play ‘My Other Half’ statically (with the mic on and off axis), and moving about (to see how susceptible the mics are to comb filtering in such a less than ideal interior space). To make it easier to follow the various positions, I have put this test into a video. Oh, and, yes, I know the 180 degrees off-axis test is fairly mad!

Putting the shotgun mics into tougher conditions, I then dragged Chris onto the pavement outside the theatre to ad lib as if for an interview (quite fairly, he chose to promote the theatre where he works!) against the backdrop of the entrance (which houses a bustling café), with noisy traffic and people behind the mic on a busy junction at the centre of the town:

Play it again, Luke

Rarely is a shotgun mic much use in a music studio or, even, for remote location recording of music (e.g. in a church or concert hall), but sometimes the polar pattern of a shotgun mic is necessary. Recording music is also a good test of any mic, so to put the Rycote’s mics to this use I chose to record a guitarist in an indoor non-studio space (a woodcarver’s workshop).

Here are the two mics used to record ‘Moth to a Flame’, written and performed by Luke Chapman. I’ve also included a third version, with the HC-22 paired with an AKG CK94 (i.e. SDC fig 8 mic) to show how the Rycote mics perform as the mid mic and a mid-side stereo pair. The sound is just as it came off the mics, recorded into a Sound Devices MixPre-3.

And here is a short video with clips of Luke Chapman playing the guitar and singing, with the sound (as shown on the screen) switching from HC-15 to HC-22 to HC-22+AKG CK94 mid-side. Again, there is no editing or effects. The limitations of using a single shotgun (even if in one version, combined with a fig 8 side mic) for recording both guitar and vocals simultaneously are evident, and not something I would normally do (in fact, I’m currently recording an album with Luke using three fig 8 LDC mics), but it worked rather better than I thought. And, of course, sometimes a shotgun mic (or shotgun-based mid-side pair) might be an effective solution: e.g. a run-and-gun recording of a busker in a noisy street.

Let’s get physical

While the sound of the mics is the focus of this review, another aspect not clear from the specs is the physical nature of the mic. That is the build quality (insofar that this is clear without dismantling it and using it for years in all conditions), the handling noise (shotguns are forever on the move, at the end of boom poles or on pistol grips), and susceptibility to wind noise.

Build quality seems excellent. With no high-pass filter or pad switches, there are no moving parts to assess, so it’s a simple design. The mix of materials is unusual feeling, but not in a bad way. The brass barrel of the pre-amp (as opposed to the aluminium of the capsule section and interference tube) has a bit of heft (though these are light mics at 90g and 100g): this takes the centre of gravity of the HC-15 a little back from the red ring, and with the HC-22 it is around the paired slots behind the diaphragm. Access to the innards is evidently by release of the brass circlip in the XLR socket, which seems preferable to a screw (the circlip also grounds the mic body to pin 1): I didn’t open up the mics though…The wooden cases are classy, well made and close in a satisfying way (simple pleasures!): not sure many would use them in the field though. More attractive is the lack of gubbins with the mics: no additional equipment means you aren’t paying for things you so often don’t need.

Close-up of the XLR socket with circlip.
How they come: just the mics, the rather lovely cases and the simple cardboard packaging.

Testing for handling noise transmitted via a boompole required some deliberately bad booming aiming for maximum transmission of vibration to the mics (on an Invision 7 suspension). Unsurprisingly the two Rycote mics are pretty similar, with all the unwanted noise below 50Hz (and therefore addressable by a low-cut filter, if not, of course, by better technique). By way of comparison, here are test files for the HC-15, the Oktava MK012 with the hypercardioid capsule, and the AKG CK93 (hypercardioid), which reveal no major differences:

Wind noise on a mic varies with polar pattern, of course, and, while wind protection from a slip-on foam cover, through softies to a full blimp can address the issue, it is good to examine the baseline susceptibility. For this – not least given relevance to actual use – I have just gone for some simple fast boompole swings, with the mics mounted together. The HC-15 and HC-22 are not that different, with the HC-22 (reflecting better rejection of the sides) performing better than the smaller shotgun:

The susceptibility to wind appears pretty normal for a shotgun mic and even lower-cost versions perform well. Here for example, is the HC-22 compared to the Rode NTG1 (levels adjusted to reflect sensitivity), with the latter a bit quieter:

But comparing the Rycote shotguns to other types of boompole mics – in this case hypercardioids – shows a significant difference: even the more wind-susceptible HC-15 easily outperforms the AKG CK93 and, by a huge margin, the Oktava MK012:

Silence is golden

Of the specs the one that immediately stood out to me was the 8.5 dBA (+/- 2 dB) self-noise. This is about as low as it gets for a shotgun mic (think Sennheiser MKH 60 at 8dBA) and is much better than most of the professionals’ favourites. Diaphragm size is a significant factor in mic self-noise, and, while the size isn’t published, Rycote have told me that a 17mm-diameter diaphragm has been used (not bad in a 19mm-diameter mic body). Of course, not all mic manufacturers measure self-noise in the same manner nor is all self-noise the same, so my first test with the mics was to record nothing. Well, as near nothing as possible outside an anechoic chamber or a nuclear bunker: in the hallway of my house in a rural village, I closed all doors, turned off the mains electricity at the consumer unit, and left the two mics recording into a Sound Devices MixPre-3 (EIN -130dBV/-128dBu) along with a Rode NT2-A (at 7dBA in the same ball park). Self-noise was indistinguishable between all three mics. There’s not a lot of value to uploading WAV files showing the slight hiss with gain cranked up wildly, simply to confirm the published spec, but listening to the boompole handling-noise sound samples above makes clear the difference between the Rycote mics and mics with higher self-noise (the AKG CK93 self-noise is 17dBA and the Oktava MK012 self-noise is 18dBA).

Final thoughts

These tests are neither exhaustive nor especially technical: no anechoic chambers or such like were involved. Nor do they rigorously compare the HC-22 and HC-15 to a whole range of other shotgun mics. But the process of carrying out the tests has shown me that Rycote’s first foray into mic design has huge merit: these mics thoroughly deserve to be considered as alternatives to familiar mics above and, indeed, below their price point. The low self-noise and healthy output makes the mics obvious contenders for nature and effects recording; the same attributes, low weight and good off-axis sound make them contenders for film and TV sound; and the same specs/construction for the two models with different interference tube lengths mean that they are ideal if you want to swap seamlessly from one type of shotgun to the other. Having got my hands on them, I certainly don’t want to send them back to Rycote!

Audio Gear

AKG Blueline mics

August 28, 2021
AKG CK91, CK92 and CK93 rigged for testing

Having had the hypercardioid (CK93) capsule of the the AKG Blueline modular mics for some years (with the SE 300B body/pre-amplifier), I picked up the fig 8 capsule (CK94) and another SE 300B a few months ago (see my post on it here), and have just now added the CK91 cardioid and CK92 omni capsules to the family: a good used bargain, all the way from Shetland, in excellent condition. Although the CK91 cardioid was apparently a staple of radio studios etc. for many years, in the filmmaking world a myth has built up that the hypercardioid was the cream of the crop and by far the best capsule. I suspect this came about since the AKG CK93 is an excellent hypercardioid, and much better than the few alternatives that were available for a modest price (e.g. the Oktava MK012) rather than based on any actual hands-on comparison between the different Blueline capsules.

Certainly, I have begun doing tests and am impressed straight away by how remarkably similar the capsules sound – initially just testing on acoustic guitar and vocals. There really is no stand out or weaker capsule amongst these four (I can’t speak for the CK98 shotgun capsule, which I don’t have and haven’t heard). And equally impressive is how rounded or smooth they all are. For instance, the CK91 cardioid has none of the brittleness of my Rode NT55 cardioid capsules. A surprising extra is that the AKG CK91, CK92 and CK93 capsules also have less evident self-noise than the Rode NT55 mics, despite the specifications suggesting the reverse (17dB vs 15dB). These really have to be some of the most underrated mics out there: great value new (if you can find stock still, as they appear to be being discontinued) and even better used.

I bought the latest two AKG capsules to give me more options for a mid-side pair with the CK94 fig 8 capsule. OK I could use other SDC mics I have (such as the NT55s), but it is nicer to have a more consistent sound across the pair in the mid-side array: that the AKG capsules also sound better is a bonus. When I get the opportunity I will post some samples with the various capsules.

AKG CK91 (cardioid), CK92 (omni), CK93 (hypercardioid) and CK94 (figure of eight) capsules on SE 300 B pre-amplifier bodies. Note some slight visual variations over time with the pre-amplifiers (oldest is on the CK94; next oldest on the CK91 and CK92; and the newest on the CK93): I can’t hear any difference in their performances, but have yet to compare the circuits.

Audio Gear DIY Projects

Mid-side with AKG CK94

May 25, 2021
AKG CK94 (top) and CK93 (bottom) in Rode Mk1 blimp suspension

I’ve had one of the AKG Blueline mics for years. This has the CK93 capsule, which is an excellent mid-price hypercardioid SDC mic that has proved great for booming indoor (and, on occasion, outdoor) dialogue. I have also used it for music recording where I needed a narrower polar pattern than cardioid. It is leagues above my Oktava MK012 hypercardioid – so beloved by indie filmmakers – in terms of build quality, handling noise, and features (having low-cut and attenuation switches).

From time to time I’ve wondered about the other interchangeable capsules in the Blueline range and, above all, about the CK94 – the figure of eight capsule. Of course LDC multi-pattern mics include a fig 8 polar pattern and, paired with another mic, this allows mid-side recording, which I have done many a time. And, as I have posted, with a massive DIY blimp I have even got such an LDC pair outside for field recording. That said, it would be useful and, for most uses, more practical to have a compact SDC mid-side pair. The standard for field-recording pros is the Sennheiser MKH30, which, while excellent and with the advantage of humidity-beating RF technology, has the distinct disadvantage of cost: it has a street price of around £1500, and even used ones seem rare below £1000. Add another Sennheiser MKH mic (say an MKH40) and wind protection to fit and you will need to spend £3000 or more. Unlike other polar patterns, SDC fig 8s are rare, and there are few more affordable ones: ignoring the clunky pseudo fig 8s made by Oktava and Kortwich (made using two cardioids mounted back-to-back, giving a T-shaped mic), the only affordable true single -diaphragm fig 8 other than the AKG CK94 is the Ambient ATE208 Emesser. The latter, however, has a lot of bass roll-off due to it being tailored to match the off-axis response of a shotgun mic (its intended partner). Recently, boutique Taiwanese mic-maker B9Audio has produced the CM180, but it is only available direct from the maker: so this means significant shipping and duty costs need to be added to the US$749 price. Reviews are also thin on the ground to say the least.

So, with all this in mind, the AKG CK94 remains the most viable affordable SDC fig 8 for general usage (i.e. music as well as film sound). Although now out of production (AKG/Harman/Samsung appear to be phasing out the whole Blueline family and the CK94 was the first to be discontinued), at the time of writing it is just possible to find one or two new examples for sale: with the SE 300B amplifier/mic body, street price is around £600. But I’ve been keeping my eye on the used market, and was please to spot one on the Saturn Sound website (where there is a list for a grand closing down sale of mics – with some very rare examples), and – together with the SE300B amplifier/mic body – the other day I became the owner of a very good condition example: indeed, during a pre-sales check, Ashley Styles of Saturn Sound thought the capsule a bit noisy and replaced it with one he still had. All this, plus delivery in person (he has retired not so far away), for a remarkably affordable £200.

I had no concerns about the CK94 for music or louder effects recording, but, with 22dBA self-noise (a long way from the MKH30’s 13dBA) my hopes were low for recording quieter ambiences. So I was surprised how good it sounded during an initial test recording the ambient noise in the garden (in a village in rural Norfolk). You can have listen here:

I was expecting something much noisier.

In terms of rigging it up for field recording, I purchased a couple of the older style (i.e. lower profile) back-to-back clips made by Rycote (ref. no. 048460), which, unlike the new fit-any-mic clips Rycote make for MS pairs, neatly fit into a Rode Mk1 blimp and have lugs to attach to the suspension bands: the mics sit centrally and with a healthy blimp diameter of 100mm there is still plenty of air space around both mics. The CK94 has to project further forward given the location of its capsule (the centres of the two capsules should align, of course). I’ve added a DIY conn box equivalent (a clamp for the two thin cables – Sommer Cicada – that go from the mics to the DIY boompole-top XLR holder) to avoid the two heavier cables entering the blimp, so I’m there with a very nice sounding SDC mid-side rig for a very modest outlay. And, of course, I can use the AKG CK94 with mid-mics other than the hypercardioid CK93: for example, my Rode NT55 mics give me cardioid and omni mid-mic options. I’ll post other recordings – including music – with the CK94-based mid-side rig in due course.

With blimp on, and showing the double XLR holder at the top of the boompole
And a close-up of the DIY double XLR holder at the top of the boompole
Audio Gear

Testing the new Rode Wireless GO II

February 27, 2021
Rode Wireless GO II recording into an Android phone

Putting your equipment through its paces is part of getting to understand it properly. Given its newness (only released this week), my tests on the Rode Wireless GO II might be of wider interest: so here’s a post about them.

First, a quick bit of background. I’m not normally in a rush to adopt new technology, but this week – following the death of an old handheld recorder (my Sony M10) and while planning a couple of projects – I was looking at lav mic self-recording back-up options, and Rode’s new offering seemed on the nail and very timely. I know the first version was nothing like a professional wireless mic set up (not least for its dropouts when out of line-of-sight), but I’d found it eminently usable for the particular and less exacting uses I bought it for: in particular, the sound quality stood up compared to the same lav mic hard-wired. So, rather than wait for anyone to get round to a thorough test – as opposed to the numerous unboxing and product review vlogs that will doubtless flood YouTube – I ordered one from CVP.

Overall audio quality

There are different aspects to the audio quality of such a system, including its on-board mics vs external lavs, its on-board recorder vs transmitted audio, and both the recorder and the transmitted audio vs a better system.

Using a Sound Devices MixPre-3 to provide a decent sound source into the Rode Wireless Go II transmitters

Most interesting to me was to take the on-board and external lav mics (both of which have relatively high self-noise due to their small diaphragms) out of the equation, and test the recorder and wifi alone. For this, I fed the two transmitters with a stereo signal of a simple acoustic guitar recording (recorded with a spaced pair of 7dBA Rode NT2a mics in fig 8 mode) via my Sound Devices MixPre-3 (feeding a signal from the stereo out at -6dB to give a reasonable level at the transmitters, comparable to that of the mics above). I recorded the transmitted signal via the USB out of the receiver. Here are the clips, with no processing added:

Original MixPre-3 recording:

Rode Wireless GO II on-board recorders in uncompressed/broadcast mode:

Rode Wireless GO II on-board recorders using the compressed/standard mode:

Rode Wireless GO II transmitted recording:

The verdict? Well, see what your ears say. The most obvious positive is that the Rode Wireless GO II on-board and transmitted audio show remarkably low self-noise: there is effectively no hiss in the short lead-in. The most obvious negative is the lack of bass response: OK the datasheet shows a frequency response graph with a sharp fall-off below 100Hz, but this appears to relate to the mic. Needless to say, you can boost the bass response in post, and here is a quick EQ’d version (I looked at the bass fall-off in the Rode Wireless GO II using pink noise, though my resultant EQ might be a bit too heavy – but it makes the point):

And, of course, what is effectively a high-pass filter isn’t a significant problem with intended use (speech) and will aid reduction of wind noise and other unwanted low frequencies.

So my overall view on the audio quality of the electronics? Well, the transmitted and on-board recordings sound surprisingly good: OK not up to the level of a Sound Devices MixPre-3 and not ideal for music recording, but easily good enough for use with the on-board lav mics or external lav mics (or other PIP mics such as Micbooster’s Clippy mics) for speech or ambience/nature recording, and perhaps usable – in the way that you might use a small handheld recorder – for music recording where, for whatever reason, a better and more conventional set-up wouldn’t work. Also, the compressed on-board recordings don’t sound too bad at all, despite my natural dislike of lossy compressed formats!

On-board mics

Given the mic in the original Rode Wireless GO, I was reasonably optimistic about it and, also, conscious that a) different people like different lav mics and b) I don’t own any of the more expensive lav mics (such as those made by DPA). But, for what it is worth, here’s a simple comparison of Rode’s lav mic (that’s their more expensive one – at c.£160 – and perfectly usable) vs the on-board mic recording a voice (apologies for the performance!), and recorded via the Rode Wireless GO II’s receiver (both digital out, into an Android phone running USB Audio Recorder Pro, and via the 3.5mm output into a Sound Devices MixPre-3).

Rode Wireless GO II on-board mic via digital out on the receiver:

Rode Wireless GO II on-board mic via 3.5mm analogue out:

Rode lavalier mic plugged into Rode Wireless GO II via digital out on receiver:

Rode lavalier mic plugged into Rode Wireless GO II via 3.5mm analogue out:

The verdict? The on-board lav mic is quite usable if – and this is the key – you don’t mind the transmitter being visible too. The much more secure furry windshields of the new model at least make this more feasible. And as for the difference between digital and 3.5mm output, there is little in it. Well at least with a decent sound recorder: of course, the difference will be greater if choosing between USB into a phone and analogue into a camera with poor audio.

Range and dropouts

As I said, I found the original Rode Wireless GO usable for my purposes, but I can’t deny that a more robust wifi signal wouldn’t be useful. Indeed, for many, it would be essential. The 200m line-of-sight spec for the new version (vs 70m for the original version) shows an improved wifi capability, and this is borne out even in initial, simple, testing. For example, whereas the original Rode Wireless GO – under my test conditions (a rural Norfolk village) – experiences dropouts from around 20m when worn on the rear of the subject (or ‘talent’) – i.e. blocked by the wearer’s body – the new version worn in the same way is good for about 35-40m. Obviously, different locations will produce different results, but this suggests much more suitability for, say, wedding videographers, where, of course, the recorder provides a back-up anyway. For professional sound recordists’ use (e.g. television and film) the improved signal strength is probably immaterial as the units lack the range, features, robustness and ease of control of professional wireless systems such as those produced by Audio Ltd. and Lectrosonics.

Field-recording (an update of 15.3.2020)

Rode Wireless GO II TX units in action for stereo ambience recording…

Having had the Wireless GO II for a few weeks, I’ve had a chance to use it for different scenarios, one of which is as a remote field recorder. Here the ability to use the two TX units as a remote spaced-pair of omni mics opens up all sorts of possibilities, not least recording sounds of nature (such as timid birds) from afar. Of course, if the tests above suggest that the on-board mics or the electronics aren’t are not high enough quality, you can simply use the system for monitoring: for example, running SDC mics into a Sound Devices recorder, and plugging the TX units into the recorder’s stereo out so you can hear what is being recorded from afar. Taking the Sound Devices example you could, of course, use the wireless remote control (Wingman) for the recorder too, though I haven’t tried that combination or, indeed, tested the Bluetooth range. Anyway, what I have tried out is simply recording remotely with the on-board mics, both within a Rode blimp and with their supplied fluffy windshields: of course, the former, while restricted to 35cm spacing, provides more wind protection, but the Wireless GO windshields on their own were surprisingly good and allow any spacing (in my tests this happened to be 46cm). And the fluffy windshields of the new TX units fit much more securely than those of the original Rode Wireless GO. So here are a couple of examples, one in very high wind (we had gales at the weekend) and one in slightly less windy conditions. Both just with the TX units alone and their own fluffy windshields, and simply placed in a holly tree in the garden (near the road), as in the photo above. The recordings are from the RX unit’s USB output.

Stereo ambience recording (garden in high wind):

Stereo ambience recording (garden in moderate wind):

Audio Gear DIY Projects

Primo capsules – for lav mics and DIY

February 7, 2021
A pair of the tiny Primo EM272 omni capsules: add two wires and a 3.5mm plug and you are ready to record!

Primo microphone capsules are much-loved by the DIY crowd, especially the omni EM172 (now replaced by the EM272) capsule: it is a 10mm capsule with 14dBA self-noise. As such it offers similar scope to a lavalier (lav) mic for times when you want something much smaller than a small diaphragm condenser (SDC) mic, but has much lower self-noise: lav mics typically have around 22-5dBA self-noise, which can be pretty noticeable for many recording uses, such as ambience and nature recording. The sound quality is on a par with capsules used in mid-range handheld recorders, but, of course, once you have external mics you can be much more flexible. For example the omni mics on the much-loved Sony PCM10 are too close together for stereo, so plugging in a pair of EM272 mics allows for a proper spaced pair: you can clip those to your hat, the sides of your specs or, to look slightly less silly and to avoid your head movement giving odd shifts in the stereo image, to the sides of a bag or rucksack.

And the best thing about the Primo capsules is that they are cheap. Currently in the UK an individual bare capsule is £12.78 from FEL Communications Ltd (Micboosters): FEL/Micboosters also offers various versions (e.g. pre-soldered), other Primo capsules (including cardioid and figure 8: see below), matched pairs and, for those not into DIY, capsules already made up into finished mics – their Clippy and Pluggy models. There are a couple of other manufacturers who use Primo capsules in affordable mics, the most well-known of which is LOM in Slovakia, but I think Micboosters is the only one that also sells the bare capsules: and it is one of those great small British companies, run by the very helpful Nick Roast, who has worked as a BBC sound engineer for over 30 years.

A pair of Clippy mics

I have a pair of the Clippy mics (together with Rycote furry covers that are made specifically for them), which are useful for discreet or minimalistic stereo recordings and as lower noise lav mics for dialogue. And I have used bare EM172 capsules for what Curt Olson – who inspired my experiments – calls a ‘head-spaced parallel barrier array’, albeit in my case small enough to fit inside a Rode Mk1 blimp and with some of the mic placement attributes of SASS arrays: the circular baffles are c.90mm diameter and the mics are 160mm apart. Surprisingly effective. I’ve also used an EM172 to make a boundary mic, with the capsule set off-centre in a disk of perspex (150mm diameter and 5mm thick). Perhaps next I should buy some silicon ears (I see Micboosters sell them too) and make a binaural head with a pair of EM272s, as others have done.

Primo also make a single diaphragm figure 8 capsule (the EM283), again 10mm diameter, but this is not normally available via retailers. I noticed that Micboosters had started selling them and, as I had never heard of the capsule nor could find anything about it via the internet, I bought one for the princely sum of £19.68 for fun/curiosity. The specs are not as attractive as the EM172/EM272 and the 22dBA self-noise might be rather too high for many, but it is fine when used as part of a mid-side pair for louder sources such as music or some street ambiences. I found that the EM283 capsule needs better RFI screening than the EM172 and EM272, but that’s nothing unusual. I just bunged it in an old sawn-off shotgun mic tube for testing and, though this makes the mic unnecessarily large, it is fine – all hum eliminated. At some point I’ll get around to making a smaller housing with the fine mesh screening I have bought for the job. Not entirely sure if I’ll make much use of this capsule, unlike the EM172 and EM272 ones, but it has proved useful in an odd way: I had been thinking of acquiring an AKG CK94 figure 8 mic to provide the side mic for a mid-side pair with my CK93 hypercardioid, but was worried about self-noise (the CK94 is also 22dBA) and this convinced me that for my intended use I really do need something a lot quieter (so will need to save for an MKH30). UPDATE 26.5.2021: despite my conclusions about the EM283, I did buy a used AKG CK94 after all (a bargain came along) and its theoretically identical self-noise of 22dBA is not at all problematic. Lesson learned? That not all self-noise specs are equal! I’ve written a blog post about the new mic here.

So the final word: I’d really recommend playing around with bare Primo capsules as a cheap way to learn about arrays, and, even if DIY isn’t your thing, I’d recommend a pair of ready-made Clippy mics with these capsules as a great and very affordable alternative to a pair of lav mics for those occasions when SDC mics (and P48 power) aren’t feasible.

Primo EM272 capsules as delivered: matched pair with measured sensitivity a bit better than the published specs.
A head-spaced parallel barrier array – with the influence of SASS arrays – built to fit inside a Rode Blimp.
A boundary mic with an EM172 capsule: so simple and cheap, but better performing than so many commercial offerings.
A size comparison of a Clippy mic and a miniature lav (in this case my Rode lav). The Clippy’s EM172 capsule makes it rather chunkier, but for many uses this isn’t a problem, and it is still small enough to hide under much clothing.
Experimenting with a Primo EM283 fig 8 capsule: mounting it inside part of an old shotgun mic body.
And using the Primo EM283 fig 8 mic as the side mic in a mid-side mic pair with a Rode NT55.