Sunday, 13 March 2011

[Review] Minerva Mi-1 Custom In-Ear Monitors

I am finally able to bring you my review of the Mi-1 custom in-ear monitor made by Minerva Hearing Protection. The Mi-1 is Minerva's entry-level single balanced armature custom in-ear monitor made of silicone.



First of all, I would like to apologise for the length of time it has taken to get down my review of the Mi-1 and I’d like to explain the why’s and what for’s before we get into the nitty gritty of the ‘how they sound’.

To try and find out exactly what I wanted about the Mi-1’s, I was emailing back and forth with Lee at Minerva for a good few days to gauge the depth of knowledge and level of customer service. No detail was left out and Lee answered any question I had fully, no matter how small it was. I was impressed with prompt and detailed replies and went for the purchase.

The audiologist contacted me a few hours after I placed my order and booked me in to get the impressions taken. The impressions taking process was quick convenient and painless, with my audiologist being a pleasant gentleman who had taken many impressions over a 6 year period. He packaged them up and sent them down to Minerva that afternoon.

Ten days after my visit to the audiologist I had my Mi-1’s in my hand and very soon after that, in my ears. The fitting was quite comical and I truly understood what people meant when they said that fitting custom IEM’s for the first time was a bit of a challenge. Isolation was miles better than my universal tryouts and comfort was phenomenal, you could tell that Minerva had been making custom ear fittings for years, they were spot on. Unfortunately when it came to the sound, I was very disappointed and immediately wrote up an email, detailing a lack of bass response in one ear and a strange filter which seemed to be applied over most of the audible spectrum, and continued my listening over what felt like a long weekend. Things did not change or improve, using various different sources and mostly FLAC quality audio tracks, so an email went to Lee.

Continuing a trend of swift responses, Lee had contacted me by phone within 15 minutes of the email hitting his inbox. We had an in-depth discussion about what I was hearing and it had us perplexed, as well as the Minerva technicians. Apologies were made and a new set of Mi-1’s were put into production immediately whilst I returned my Mi-1’s. A couple of emails followed and the issues were revealed to be a slightly compressed tube which severely restricted my bass response in that one ear and the filter-like malaise over my sound was caused by faulty transducers, a faulty batch.

My new Mi-1’s arrived last Saturday, just 6 days after I had brought up my issues with Lee. They came fitted with new filters to help smooth out the sound curve some more as my first pair seemed to be a bit heavy in places, a Pelican 1010 case and my connector had been upgraded to a Neutrik connector as a further apology for having issues with my first set. An unexpected bonus to what I would have described as fantastic customer support already!

Now I finally had some Mi-1’s to listen to and listen I did!

Most of my listening was done with my HTC HD2 phone, Fiio E5 portable amplifier and a mixture of 192kbps (iTunes), 256kbps (Amazon) and FLAC sound files. I also tried the same sound files on my PC with Onkyo HT-R518 Receiver in between.

I found that my HTC HD2 would easily drive the Mi-1’s to a desirable audio level and beyond. I keep the Fiio E5 amp in the loop because the volume control system of the HD2 is awful and the E5 makes small step volume adjustments very easy.

Disclaimer: I am an audiophile in training. I have my training wheels on and have used the Audiophile Glossary of Terms to help me better describe what I am hearing. My previous IEM history includes Monster Turbines (both real and fake), Head-Direct RE-ZERO’s and a pair of Sony IEM’s that came with my now retired Sony Ericsson w880i mobile phone. This is also my first Balanced Armature monitor. My music tastes are very varied, switching from artists such as Darren Hayes to Static X, 50 Cent to Jamiroquai, Daft Punk to Boyce Avenue and you can even include Bon Jovi, DJ Tiesto and Michael Buble.

Thanks to the power of Amazon.com, the widget below has a short preview list of some of the songs that helped in my testing of the Mi-1's.


First to note is the soundstage of these monitors, it is leagues ahead of my previous monitors. The sensation of sound seems to extend nicely to the left and right beyond my ears, vocals feel slightly forward and other instruments feel slightly behind me. It’s probably the thing that I am having the most trouble adjusting to with the Mi-1’s.

The level of musical detail and instrument separation are also leagues ahead of my previous monitors. I am hearing much more than I have ever done so, even with the RE-ZERO’s which were also a rather large leap above previous outings. It’s quite wonderful to be able to detect a single cymbal clash or drum beat and be able to follow the sound after the initial impact sound comes through. Low level detail is fantastic.

Speed was a term which confused me when I was just a newbie here. I read |Joker|’s reviews and never really understood what he meant by speed, but now I feel like understand it clearly. With some tracks, DJ Tiesto’s Adagio of Strings comes to mind first and foremost, the Mi-1 reveals so much more detail in that track than the RE-ZERO did (or could).

Bass is an area I wasn’t much blessed with in the RE-ZERO’s and the Monster Turbines made my general music too fatiguing to listen to for more than about an hour and a half. The bass feels tight and with a satisfying but not fatiguing impact.

The mids and highs are well presented with the highs giving me the impression of running out of steam towards the end. This is something I expected with a single balanced armature set of monitors from my basic reading. I honestly feel disappointed with the highs in the Mi-1 but I know that this is because I have came straight from the RE-ZERO to my first single balanced armature monitor. I can now curse the fact that I did not have the money for an Mi-2 or Mi-3!

One thing I did pick up on, or feel, is that the vocals in tracks by Savage Garden or Darren Hayes is eerily accurate. Darren Hayes is my favourite artist whom I have listened to for over a decade and seen live in the fair city of Newcastle three times. If I pump some of his live recordings up to ‘live’ volume, close my eyes and listen, it feels very much like I am back in that in Newcastle City Hall.

I have borrowed some of the next part from |Joker|. I hope he doesn’t mind but I love the layout and it pulls out some excellent points into a more concentrated form.

Accessories: A small tube of Aloe Vera gel for in-ear application, a nifty cleaning tool, a metal shirt clip, a soft leather-like carry pouch. A basic pack of accessories and I like the touch of aloe vera gel which overall feels like above average quality with the exception of the cleaning tool. I’m not sure I can criticise the cleaning tool per se but it doesn’t feel great and reminds me of those small pens you get in Argos or the bookmakers. Probably just me as it does exactly what it’s supposed to do.


The Pelican 1010 case comes with your name and model number engraved on the top. From the reviews of this product, it is pretty sturdy and some manner of water resistant. It’s not something that I would be using too often in an outside environment as I usually travel light but it would be ideal for anyone who wants to put their Mi-‘s in a gym bag or travel bag and have the peace of mind that their monitors will be safe.


Microphonics: My Mi-1’s are an ‘over-the ear’ design and as such, microphonics is very low and is lowered even further by the shirt clip.

Comfort: In-ear monitors made specifically for my ears by a company that has been making custom ear fittings for decades? Full marks here.

Isolation: Perfect seal and a nice full shell design give supreme isolation. I live on a busy main road and walking down there whilst listening to the Mi-1’s at a relaxed level, I could only barely make out the sound of tyres on tarmac during the very music-quiet times. Unfortunately I did not have the benefit of a heavy goods vehicle or emergency services vehicle, which are very common normally, hurtle down the road beside me to test it further.

Cable: The cabling feels rather thin but reassuringly tough, kevlar reinforced as standard. One week on, my cables still retain the memory of the looped state they arrived in. During use over the ear, they don’t seem to have any noticeable memory properties.

Customer Service: Bad customer service is noticed. Good customer service is expected. When the customer service experience is great, you sit up and notice. From pre-sales queries to post-sales issues, I have received one of the most positive customer service experiences I have ever had.

Queries responded to within 24 hours, any issues discussed and resolved as soon as possible. Friendly, helpful and I wish more companies would take such a stance.

Conclusion: A very capable and fun custom which brings out a lot of detail in tracks and has what I feel, an accurate reproduction of the track. An excellent entry into the world of customs.

Some might feel that for £150 you could get a better set of universal earphones. I believe that the Fischer Audio DBA-02’s, when they are in stock, are about £110-120 before any possible (probable) VAT/Customs charges. Whilst this might be the case for some people, I value the added comfort and isolation afforded by the custom Mi-1’s and can’t say that I’m in any way disappointed with the sound that I’m getting for my money.

Additional: Following the incident with my faulty transducers, Minerva have tightened up their quality control systems and testing procedures to reduce the chance of this happening again.

Also, Minerva are very much listening to the opinions of the public and the audiophile market to provide an even better audio experience. I have been speaking to Lee and I have the opportunity to try out a different filter for the Mi-1 to see if things can be improved further. If I take the chance, I will definitely report back but it’s definitely a sign that Minerva are striving to improve their custom monitors and are certainly a company to watch.

This review is also available at Head-Fi.org Forums.