First of all, I would like to thank Harry @ TekFusion for choosing me as one of the reviewer of TekFusion's TwinWoofer. I am honestly impressed by the sound quality the TwinWoofer outputs for the price. Even at $50, they certainly sound better than what they actually are. Aside from the sound quality, the TwinWoofer uses all metal housing and that is extremely durable. Apart from that, I like the shape of the housing. The housing feels robust on hand, beautiful to eyes and comfortable in the ear. Inserting them in ears is a piece of cake as well. The only build quality issue that I have, if any, is it's rather microphonic and thin cable. Other than that, I do not have any problem using it throughout my listening. Please note that, the unit that I will be using in this review / impressions have only roughly 10hours + of burn in at the time of writing. It is all based on stock, single flanged silicone eartips. The bass extends extremely deep and powerful as the name suggested. Electronic music listeners will definitely enjoy the deep whopping sound in the music. The only thing that is not done right in the bass region is the lack of control in the bass. It bleeds into the midrange. Surprisingly, despite the powerful bass, the midrange does not feel recessed at all. While it is not well textured or energetic, it is not given up because of the powerful bass. I wish I can better feel it when MJ shouts "Slave to the rhythm!" thought. Soundstage is impressive for an IEM. There are no audible hisses or grains at the highs. Equalizing down the bass does pretty much solve the bass problem, otherwise, eartips rolling does help too. I recommend switching to eartips with wider bore. I next paired the TwinWoofer with my recent iFi Micro iDSD. It's pretty much overkilling indeed, but the TwinWoofer does scale better. I set the power to "Eco" mode and "Ultra High Sensitivity" mode in IEMatch as it is an extremely easy to drive IEM. It opens up the midrange and help tighten the bass by a little. I like the result but I definitely don't see the need of overkilling. Perhaps, the FiiO E07K amp/DAC will do the trick too but will report back when mine came back from my friend this weekend. I have honestly never been so impressed by a sub $50 IEM and the TwinWoofer did it. I will be comparing them side by side to the RockJaw Alfa Genus, JAYS A-Jays Five, Jabra Vox in the following week and will report back soon! Till next time Billson xD Brooko's Full review & Comparisons: http://www.head-fi.org/u/170914/brooko BillsonChang007 [me] Review: http://www.head-fi.org/products/tekfusion-twinwoofers/reviews/11474 NOTE: I did not add the Micro iDSD in the above review because I will be featuring the TwinWoofer in my Micro iDSD's full review already which will be posted soon as well.