Aim Audio’s ‘Useful INNOVATIONS in Audio DESIGN’ mantra really isn’t just marketing speak. Honestly.
The team looked at what we could achieve beyond the regular engineering cycle, to make a difference for musicians and recording engineers in their daily recording lives.
At the same time, we developed a whole host of exciting technologies that we genuinely asked why it hadn’t been done before.
Transformer or Electronically Balanced?
But let’s just cut to the chase and through the blurb to finally lay it all out.
What makes a topology?
Originally, transformers were used in the output stages of audio gear because they are excellent at isolation, noise rejection and allowed for longer cable runs. While the later introduction of cheaper electronic output designs allowed for faster transients, at the expense of many of the transformer benefits (or disadvantages, depending on your point of view).
In our development cycle, our team looked at a number of types of circuit for our mics, in the end we hit upon something that we think is quite special.
The perceived wisdom is that a good transformer balanced output microphone tends to have a niceness that, while it can add richness to the signal, isn’t completely 100% accurate. At the same time this style of output stage can add a general flavour that can glue, complement and enhance many styles of an artistic performance at source during the recording and without phasing issues – rather than reverting to or relying on EQ and/or post processing added at mixdown, that can cause all sorts of phasing issues.
Transformer based output stages tend to have a slightly thicker and richer LF, plus a slightly airy top end and a slower transient response. This can be useful for all sorts of audio – from aggressive or velvety smooth vocals, to heavy guitars or a brass section.
While Transformer-less, Electronically Balanced microphones tend to react much faster with transients and can handle higher sound pressure levels, even at ultra-low frequencies. This style of mic is perfect for catching fast moving audio like drum overheads or tracking acoustic guitars, without any ‘smearing’ of the audio.
This leads to the question, why not have both in the same design? Well after years of development, we can tell you the answer. Because it really is a challenge and isn’t easy to do!
Transformer based output stages are also generally hotter by around 6 dB, so if this was a simple switch between the two topologies, it would mean you wouldn’t really be able to compare on the fly or not be influenced by the “louder is better” choice, that always tends to cloud human judgement.
The Best of both worlds
Our patent-pending design allows for an instant* switch between genuine output stages AND at the same level, all without any additional pre-amplification. Choose the option that best suits the source, at source.
Testing an early PCB Stack
The unique Aim Audio switching circuit that is built into our mics isn’t just a case of strapping a transformer over the outputs and switching it in and out of the circuit either. No! It really does switch between the two distinct output topologies with an internal relay* – and the whole shebang works over regular 48 V phantom power!
Our extremely experienced microphone design engineering team spent a huge amount of time exploring exactly how to do this. In reality, we think it’s a game-changer in the industry and a world first, which is why the technology is patent pending.
Aim Audio’s electronic balanced topology is clean, has fantastic transient response and is extremely quiet.
In fact, when we first fired up our protype for testing in a real studio in Berlin (the world-renowned TRIXX Studios – with hundreds of classic and desirable mics in house) our brilliant studio engineer Fabio Buemi asked “is it switched on? I can’t hear any hiss!”. Suffice to say, this super clean mode will capture your transients fast and as cleanly as possible.
Is it on?
One of our early hand wound test transformers
While for our transformer-based circuit, the Aim Audio team developed a Custom Wound Toroidal Transformer with a nanocrystalline VITROPERM core.
That’s sounds like a mouthful, but in essence, the crystalline atomic structure of this core creates stable and pleasing saturation across a wide frequency range, but without sounding harsh and increasing brittle distortion levels that so many low-cost and regular off-the-shelf designs can be prone to.
No matter which mode we looked at, once we had the technology in place it we just had to have both in the mic!
Getting the sound right
No matter what model you choose, the sound of any condenser microphone starts with the capsule. Testing a bunch of different types of capsules in a real world environment, with real musicians, is not something that is a norm in the mic world and in most cases, this is done on a scope in a lab to fit a predefined sonic signature.
But we wanted to get a real world and subjective idea of what sounded the best for the majority of users, so rather than solely rely on the specs, we decided to do some double blind listening tests, at the same time compare this against a host of classic and competitor mics from across the spectrum.
During our development, we built a custom ‘Frankenstein’ unit so we could achieve testing as efficiently as possible.
Made using 3D printed metal (amazing technology) the lid of this special mic can be removed and the capsule can be easily changed at will
In fact, the whole process actually takes less than 15 seconds.
We selected a worldwide panel of 40+ top studio engineers, producers, influencers, voice artists and musicians to help us with these tests.
There is a cross section of people in this group, some are famous names, some are not. But no matter, all of them are experienced and have proved invaluable in their input.
We thank them so much!
Each panel member was given a selection of high quality and loudness matched audio files from each session on a variety of sources (female and male vocals, acoustic and electric guitar, voice overs and more).
They then ranked them in order of preference.
Honing the data
During the process, we also used the most popular capsule choices from initial listening sessions but utilised both Electronic and Transformer output stages. This was fascinating to see, as a capsule could be loved in one mode for one source and not loved as much on another (definitely proving the point of why the whole switching Output Stage technology is a valid thing to do!).
We went through more than 40 different capsule designs over the course of 9 months, until we found exactly the right design (and sonic signature) that got the most positive votes from the panel and beat or at least equalled the best of the competitor (and more expensive) mics in our tests.
