LOL damn....indeed not a great deal to pay 30$ for ''free'' 20$ review sample!
Again, until I can compare with my ears the Mirror and BL05s i cant conclude anything, but yes, it seem people say they use same driver. In the other hand I read conflictual sound impressions of people with both pairs. Do you have both by the way?
In speaker building world, the sound of driver could be different or percieved different by the box design.. Box usually designed to maximize bass gain in related with driver Q (resonance tendency value).. Thus there are closed, bass reflex transmission line, horn, etc).. But apparently the driver interaction with these acoustic principle is not just with the bass loading...
If we compare the same high Q midbass/Full ramge driver which could be used on closed (acoustic air suspension) and open baffle (boxless design, just use the principle of wavelength to set baffle size).. They do not sound the same on the mid frequency.. Open baffle sound very open, closed box sounded closed on the mid. Driver reaction to bass repated with their loading too... In open baffle driver will move freely (you can see it like barely move) and stable vs very wild move on closed box. This movement is supposed to be as reaction to bass frequency only.. But imagine the situation when they need to produce (vibrate) at 440Hz or 1KHz mid frequency too, with one that move in control (in open baffle) vs one that move wildly.. Which one do you think will produce better mid? Easy guess..
(Once you ever heard open baffle speakers, you don't want to go back to boxed speaker.. The problem is they are very, very big.. I once made a baffle of 1m x 1.2m (40in x 48in) just for a 20cm/8in driver... That x2 channels
![Smile :smile: :smile:](https://cdn.head-fi.org/e/people/smile.svg)
.. imagine slab of woods on your living room)
I checked Banbue's graph and comparing BL05s and Heart Mirror.. They are sooo similar on mid going up... Unless they are a case of perfect accident.. Or they actually use the same driver... I guess the 2nd would be more likely...
I read Baskingshark review and he mentioned that BL05s distorted if pushed hard.. While in opposite Heart Mirror could take equalization with aplomb.. (This is the reason I chose to get Heart Mirror instead of BL05s).. So I supposed the acoustic design of them both are very different.. In BL05s, the driver housing is acoustically designed to produce the base (increase gain acoustically).. While with Heart Mirror the design is more conservative and more 'friendly' to the driver.. So, if they sound different although they use the same driver, that is something really possible... (My 1st theory..)
My 2nd theory... As I wrote above before, I found that although Heart Mirror could take equalization well, the perceived sound balance also change with the added bass.. I prefer the non-equalized sound balance.. So.. maybe, just maybe... The same situation with BL05s loading.. The added bass on it make it perceivable different enough with Heart Mirror..