[This review was collected as part of a promotion.] When I first read the JBL charge 4 had done away with dual drivers in favor of one proprietary driver. I thought this was crazy (not in a good way) until I listened. I felt testing this new single driver against a charge 3 dual driver would be a fun and fair comparison. Standing in front anywhere from 5-15'ish feet, I could not tell a single driver from a dual driver'd charge 3. If anything, the charge 4 has more to give in ways of overall power, sound stage, tuning and loudness.
The differences seem to fluctuate depending on music. For example, Gorillaz and Princess Freesia/Soulpersona (fist bump Oluv) gave the charge 4 the advantage over the charge 3 in overall soundstage and really showed a better tuned speaker. The charge 3 sounded as if there was some type of fabric wrapped around it. Rock like Jane's Addiction seemed to make the charge 3 & 4 sound more similar than different. Maybe this was a midrange thing? Stevie Wonder and Adele (once again) showed a much better tuned charge 4 vs. the charge 3 with more defined, crisp highs, cleaner but sweet lows and just overall more power and better separation. Lumineers also had more of a cleaner sound while the charge 3 just sounded like there was fabric wrapped around it..kind of a light muffle compared to the charge 4.
I can kind of see why people claim the charge 3 and 4 sound similar but I am not one of those people. The charge 3 was a rock-solid speaker for its time but JBL DID evolve it with the charge 4. After comparing the 2 speakers' side by side in different rooms/distances/genres, I see what JBL did there with the charge 4 and I was pleasantly surprised. My hat is off to them for improving without straying from an already great recipe. Depending on your budget, the charge 3 is solid BUT if you have a little extra to drop in the charge 4 definitely do it!
Minor side note, the charge 4 does not include a wall plug but does come with a USB A-USB C cable to charge it but you must provide your own wall/usb charger. The charge 4 uses a USB C cable to charge itself but it does have the USB A output in case you want to charge your phone while on the go.
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