Earfun UBOOM L - final adjustments and corrections

I had some busy days recently, trying to optimise the sound for the Earfun Free UBOOM L. When you think it's already done, the next day you notice that there is still room for improvement. But there must be a deadline, and that’s why today I finally sent Earfun my most recent sound settings for the final firmware. There was some slight delay with production start which actually came in handy to me otherwise I wouldn’t have had that remaining time. Thanks to the valuable feedback I got from you I could use these recent days and tried to correct for the flaws some had noticed. 

I went out one afternoon and started listening outdoors, optimising the sound in real time as long as my notebook battery lasted. I couldn't do this in my garden, because my wife already started to complain about all this "boom boom boom..."

I could compare my outdoor tuning to the Soundlink Flex and Soundcore Motion+ and tyied to make the result appear better sounding than both regardless of volume level. Of course there are limits what I can offer with the given hardware, thus regarding power the UBOOM L won't be able to compete with the Soundcore Motion+, although neither the Anker sounds that great when cranked to maximum volume especially with some of the user EQ settings recently posted it will heavily distort with harder recordings, while I tried to keep distortion under control as far as possible for the UBOOM L. See the last 2-3 volume steps as headroom for softer recordings only as with most modern recordings you should get a cleaner and more convincing sound if you reduce volume 2 notches.

I readjusted both indoor and outdoor tunings slightly compard to last time, I had also recorded a video trying to show you the progress I made, but the video didn't turn out that well and I decided not to post it especially because meanwhile I corrected for some issues that came up during the video. The change in sound won't be a night and difference, but you should hear an improvement for sure. I noticed that just like it was the case with IEMs, the same goes for speakers in order to make them sound good, just that with speakers you have other problems to deal with. The key to success is to create spectrum which sounds smooth and natural. I had some kind of Dé·jà-vu when I tried to achieve this for the UBOOM L, which made me remenber how I sat there and tried to get a smooth natural spectrum for the Free Pro 2. Reducing one filter by half a dB or even less suddenly made another frequency stand out. But once I managed to smoothen some areas, the overall sound definitely improved. You will notice that music sounds simply smoother and more realistic if the spectrum has no obvious flaws. Once you reach a particular level and the overall balance correct it’s all in the smallest details, how smooth you manage to make treble appear especially as it continuously changes with listening position, distance etc. I am still convinced that the hardest part is to get upper mids and treble correct and the final result will depend a lot on how smooth and realistic those areas can be reproduced. I think I made big step up compared to before. The speaker gained some clarity although treble is even reduced compared to before.

A problem with speakers compared to a headphone or IEM is that the sound will change so much depending on listening angle, listening distance, I am not even talking about the influence of the listening room and placement. It is impossible to get a spectrum which will sound "correct" from any angle. Therefore I concentrated to at least get the most convincing result when listened exactly on axis. Indoor mode will basically sound pretty flat with some slight treble emphasis which is necessary to make the speaker sound enjoyable especially at lower levles. At the same time I manually fine tuned the dynamic bass and treble boost for lower levels, to achieve a sound which should simply remain decent. This also goes for outdoor mode which will need more overall boost due to the louder enviroment. I sat there for several hours trying to optimise the settings to make bass sound satisfying without becoming too boomy. I also noticed that extremely bassheavy recordings can create some intermodulation at high levels. I couldn't avoid this, please keep that in mind. This speaker is not a boombox, but should rather satisfy more demanding listeners (which to some degree I would also count myself to) up to elevated levels, but don't expect party levels. The UBOOM L will still perform much better than a Soundlink Flex or Flip 6 or most other similar portable speakers regardless of volume level. That’s what my goal was to make it simply satisfying enough to force me turning it on and listen to music with it regardless if I am indoors or outdoors, it’s just that if you want this big bass and higher volume, you would be probably better off with something bigger and more powerful. Although even a JBL Xtreme 3 won't really offer that convincing results at maximum volume due to too much bass reduction like I demonstrated in my video against the Minirigs a while back.

Measurements can of course help to identify some remaining problems but can also be misleading at the same time. Therefore in the end you must trust your own ear instead of trying to compensate for bumps showing up in a measurement. A portable speaker with 2 drivers as close to each other has to deal with lots of problems being directivity on one side and interference between both drivers at the other side. You can either try to get a reasonable sounding average power response when listened from all angles or perfectly balanced sound exactly on axis only which will of course make the speaker appear more dull from the side. The dispersion pattern of the drivers used is not bad compared to many others like the Denon Envaya or the Soundlink Flex but of course it cannot compete with a tweeter system like that of a Flip 6, which of axis can sound more convincing simply because it remains clearer with no interference issues. Being definitely helps here but comes with other problems of mushy treble like I have shown in my videos before.

I prepared nearfield measurements indoors and outdoors for both modes and wanted to show you how both compare, also with other speakers side by side. On top I made some outdoor measurements from 1/2m distance which of course will get lots of ground influence.

Indoor mode measured indoors in blue and outdoors in red:

You can see that despite showing a similar tendency, there are small bumps in one which are missing from the other, therefore correcting for these areas just based on a graph may lead to false results.

The same for outdoor mode again measured in blue for indoors and red outdoors.

Indoor and outdoor mode overlaid (both measured outdoors):

You can see the difference between both quite well. Indoor is pretty flat with no obvious emphasis except treble which will of course vary with the smallest change in listening angle. Outdoor mode on the other hand has bass and treble elevated while upper bass reduced compared to indoor simply to give the lower bass more space, ottherwise the sound will become boomy quite quickly like with the Bose. This boominess may be an advantage especially outdoors but actually I rather wanted to avoid any boominess. 

Here outdoor mode compared to the Bose Soundlink Flex:

The Bose has a classic V-shape with a constant raise towards bass and treble below and above 1khz. Starting the bass boost already that low is what makes the bass of the Flex so woolly IMO and simply way too much for indoor listening with no control over it. When listening to both side by side the UBOOM L will appear way clearer than the Bose regardless of listening angle and will remain more kicking at higher levels being quite a bit louder at the same time.

Outdoor mode and JBL Flip 6:

The JBL Flip 6 has also quite a flat response with a similar bass boost but bass is less punchy and gets lost way earlier thus making it very harsh sounding at high levels.

Quite interesting is the Denon Envaya vs indoor mode:

The Denon Envaya is the “most” sounded seaker here making both JBL Flip 6 and U BOOM L appear way more balanced. There is some upper bass emphasis, with some dip in the presence region and several peaks in the treble region.

I think I managed to squeeze out what was possible out of the given hardware already pushing the limits a bit at higher levels but still making it usable even for that purpose without making it fall apart somehow. The other limitation would be the directivity which I do not have any influence on. I could try to make it appear clearer from higher listening angles but this would worsen the sound for on axis listening. That’s also why outdoor mode has considerably more treble boost to also offer convincing results when placed directly at the ground and listened from above.

Once I get the final firmware I will prepare some additional videos of course in case there is still interest. I am actually quite excited about the final result and cannot await hearing your opinion.