A Lovely Ride on the Aurisonics Rocket Measurements


Click on graphs image to download .pdf for closer inspection.

Raw frequency response plots show a headphone with a somewhat reduced treble response. Peak at 2.6kHz is a tad low in both frequency and level; response above the peak is in good proportion to the peak, but also low in level.

Frequencies below about 600Hz shows a slight elevation, but it's so broad and flat I would tend to think the listener would hear it more as a gentle dip in the 500 to 1kHz region.

30Hz square wave has excellent shape with waveform top remaining very flat and above zero throughout. Low frequency THD+noise does show some modest elevation on the 100dBspl plot, but is very low on the 90dBspl plot. Bass on this earphone should be tight and punchy, but not over emphasized.

300Hz squarewave has very good overall shape, but does seem to lack speed with a slightly slow rise time and broader and lower in level initial spike. This is similarly seen in the impulse response, though the initial rise time seems a bit faster. The complete lacke of spurious subsequent noise—apart from small undershoot—bodes well for a clean sound.

THD+noise plots are a little oddly shaped. While the "sticky" eartips, as ljokerl describes, work well in the ear, they seemed to be particularly problematic on my measurement head. I tried numerous times to get a good seal, finding it very difficult. In fact, I blew up a pair of Rockets measuring them when one fell out of the ear just prior to an automated level set. Yes, it's impossibly hard to get 90dBspl at the ear when the IEM is laying on the head platform 18" below. (Sorry about that, Dale, and thanks for sending a second pair!)

Anyway, THD+noise remains below 1% even though there may be some miss-alignment due to fit.

Impedance and phase plots show a very well behaved 18 Ohm earphone with a remarkable flat impedance. Even though their impedance is fairly low, these cans should work well with sources having relatively high output impedance.

Isolation is astonishing! I don't think I've ever seen an earphone measuring -47dB broadband attenuation. These will work better than noise canceling headphones for travel use.

With 40mVrms needed to achieve 90dBspl at the ear, hese will deliver adequate volume on smartphones, but enthusiast listeners will likely want to add an amp for a bit more volume range and better control of these dandy little IEMs.


tony's picture

I met this fella on a Commercial Flight, a while back. Geez, I though he was Bill Clinton's younger brother. He was well spoken.

So now Fender has him, hmm, betcha with a no-compete clause. Which suggests Aurisonics is done, kaput, no more.

Who is servicing those 5 year warrantees ?

or, did Fender buy Aurisonics and the charming Dale Lott & Co.?

I suspect that Mr.Lott will be reading this so I congratulate him on landing something with Fender, they may have gotten the better part of the deal, Mr.Lott is a bright Penny.

Tony in Michigan

sue4's picture

You mentioning that these are rather inefficient earphones? Or it is just me whom need higher volume setting whenever using rockets?

jerseyd's picture

Glad to hear that Fender plans to reintroduce the Rockets at some point. They are terrific sounding. We have a handful of new Rockets left in stock (and on sale) at www.InnerSanctumAudio.com if anybody is looking for them.

rebbi's picture

Very excited to have just found a new period of these for purchase. Curious how they will stack up against my Etymotic ER-4P's. May turn out to be a nice alternative when I want a somewhat mellower sound or don't want to deal with that deep ear insertion. I'll report back. Thanks a lot for the very informative review.

hackmartian's picture

I picked up a pair of these early on and have been mostly in love. The sound is as good as the review suggests — by far the best I've heard anywhere under $500. I'm also a huge believer in the idea that portable gear should, by definition, be durable, and these things are. I love being able to get great sound while also being able to toss these in my backpack without worrying about them getting damaged. I've never once worried about having to treat them preciously or needing to delicately put them back in a case when not in use. I wish my phone was half this sturdy.
The only thing keeping them from true perfection is the quality of the inline mic and how finicky the mic button is. They've been back for repair twice (can't argue with that warranty), but it's clear at this point that they just never got the mic right (online discussions seem to confirm this as a widespread issue). They clearly nailed the earphones themselves, and if you don't need an inline mic or phone controls, just get the standard model and you'll be VERY happy. However, if you require high-quality phone functionality, you may need to look elsewhere.