I'll give your thread a bump. I don't have good answers to your questions, which I hope may initiate some interesting discussion.
Your image appears to show a JBL Boombox3: https://uk.jbl.com/on/demandware.static/-/Sites-masterCatalog_Harman/default/dw6fa7d1de/pdfs/HUD00002_ JBL Boombox 3_Spec Sheet_EN.pdf
Rather than pushing the stereo capability in the description, the strong bass reproduction and high maximum volume are emphasised. These two factors are significant considerations for an outdoor speaker.
Perhaps JBL's marketing department realises that the typical consumer expects stereo capability even though they are unlikely to perceive it in the device's intended application.
We can also consider that, even if left and right images are not perceived, a boombox with stereo reproduction can still be said to give a more 'open' and 'natural' sound than one with mono reproduction.
In the past, boomboxes often had the facility to artificially expand the 'stereo' effect. 'Stereo-Wide' was one such trick, but that's another story!
Your image appears to show a JBL Boombox3: https://uk.jbl.com/on/demandware.static/-/Sites-masterCatalog_Harman/default/dw6fa7d1de/pdfs/HUD00002_ JBL Boombox 3_Spec Sheet_EN.pdf
Rather than pushing the stereo capability in the description, the strong bass reproduction and high maximum volume are emphasised. These two factors are significant considerations for an outdoor speaker.
Perhaps JBL's marketing department realises that the typical consumer expects stereo capability even though they are unlikely to perceive it in the device's intended application.
We can also consider that, even if left and right images are not perceived, a boombox with stereo reproduction can still be said to give a more 'open' and 'natural' sound than one with mono reproduction.
In the past, boomboxes often had the facility to artificially expand the 'stereo' effect. 'Stereo-Wide' was one such trick, but that's another story!
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In the past, boomboxes measured almost a meter so the stereo image would make more sense, but I can't understand what benefit they get from using two channels because if the deivers were together at least it would have more efficiency but being separated the only thing that should create is comb filtering
If you place a lot of importance on comb filtering as a primary deleterious quality in a portable speaker designed for higher SPL listening in a casual environment?…..sure…..why not. Not unlike diffraction, another nit to quibble about. Wide range drivers with narrow directivity work quite well placed as close as in your example……far better that a phasey mess in mono from a stereo or mid/side mix.
Probably the biggest reason, and it looks better and more balanced.
From a technical / design point of view - stereo is perhaps easier to implement. The Bluetooth module receives and decodes a stereo signal anyway, and most small chip amps are stereo. You already have a PSU, so just add two speakers.
I've looked at the JBL specifications for the PartyBox Encore and those "fullranges" are, in fact, tweeters!
It would appear that the Encore is a mono device:
Transducers: 1 x 5.25 inch woofer, 2 x 1.75 inch tweeter
Output power: 100 W RMS
JBL says you can pair two of these devices wirelessly to get stereo.
https://uk.jbl.com/on/demandware.static/-/Sites-masterCatalog_Harman/default/dw37baa39e/pdfs/JBL PartyBox Encore_EN.pdf
Lobing can occur whenever you have a combination of two or more drivers, so is not any more of a problem with the Encore than with any other speaker system.
Possibly the wider dispersion pattern from the two outward angled tweeters better matches that of the bass driver and helps reduce the lobing that can occur between a bass driver and a tweeter at the crossover frequency.
And using two tweeters will certainly increase the high frequency power handling capability!
Possibly the wider dispersion pattern from the two outward angled tweeters better matches that of the bass driver and helps reduce the lobing that can occur between a bass driver and a tweeter at the crossover frequency.
And using two tweeters will certainly increase the high frequency power handling capability!
When you think about it, comb filtering between spaced drivers is more likely to occur with a mono drive signal because they are producing the same sound but spaced apart. If a stereo signal is used where each driver produce a different signal there is less likely to be interference issues. Additionally with a high directivity driver they may not interfere too badly, but they can be angled to bounce off different surfaces in the room and give a more immersive sound.
That makes sense @Tenson.
In the video above, the tweeters must be reproducing the higher harmonics of the drumbeats in stereo so that the microphone registers the drumbeats as left and right signals.
The tweeters' reproduction must extend into the midrange in order to give the recognisable stereo image heard on the video.
It seems a bit strange to me that nowhere in their literature does JBL state that the PartyBox Encore is a stereo device. As I suggested earlier, the stereo facility must simply be taken as a given nowadays.
In the video above, the tweeters must be reproducing the higher harmonics of the drumbeats in stereo so that the microphone registers the drumbeats as left and right signals.
The tweeters' reproduction must extend into the midrange in order to give the recognisable stereo image heard on the video.
It seems a bit strange to me that nowhere in their literature does JBL state that the PartyBox Encore is a stereo device. As I suggested earlier, the stereo facility must simply be taken as a given nowadays.
I think so, because it's all about expectations: who would ever expect to hear a huge majestic soundstage from a small portable boomboox?
Furthermore, from any stereo system the sound is perceived in the middle of the two speakers and this applies to any distance between the speakers themselves, and I don't think listening to a boombox is almost ever too critical about certain distorsions.
+1
Furthermore, writing "Mono" would depreciate the object in the eyes of a young and inexperienced (?) buyer.
As a matter of fact, about the mentioned JBL PartyBox Encore it is impossible to find the writing Mono in all the documentation, and it is certainly not an oversight.
Not true.
In that video you don't perceive any stereo effect and what you see is just an image on a smartphone that means nothing, you see just the symbol of two approximate speakers that represent two channels of the signal of the source.
TWS (True Wireless Stereo) mode
A single JBL PartyBox Encore is intended for default "Party mode" to have fun with karaoke using the supplied microphone.
If you want Stereo mode you have to buy an additional identical speaker and follow the above TWS system procedure.
If two non-identical models are paired then you obtain only the Party mode (Mono) even if 2 boomboxes are paired.
I guess that video is either fake, or whoever made it completely missed the point about how both JBL PartyBox Encore and app ("control your music and your lightshow colors") works.
That's what I initially thought.
I could hear stereo in the two music tracks at the end of the video, but is it really being produced by the Encore?