This is a review and detailed measurements of the JBL Studio 530 bookshelf speaker. They normally cost US $600 but routinely go on sale. That is how I purchased mine for US $280 direct from JBL.The 530 has a very unique style of its own:I normally take speaker grills off for measurements but because this one only covers the woofer, and it looks darn ugly without it, I tested it as you see pictured.While the outside is nicely finished for a budget speaker, I was taken back by the rough bottom of it. Some cost cutting was done there but I guess on the plus side, it is not slippery.The back panel shows dual set of connections for bi-wire/bi-amping. Personally I would rather see a single set that is spaced farther apart:If you care about country of manufacture and can't read it above, it is China.Measurements that you are about to see were performed using the Klippel Near-field Scanner (NFS) . This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise.In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.All measurements are reference to tweeter axis with the woofer grill left on as indicated Frequency resolution is 2.7 Hz.I was troubleshooting some minor issue in my prior measurements so I went all out on this speaker, dialing in 2000 measurement points to give maximum resolution for the sound expansion. Imagine trying to make this many manual measurements! This is a 2-D representation of 3-D measurements around the speaker:It took nearly four hours for the automated system to run. That by itself is tolerable, but not hearing the bass thumps in the rest of the house every few seconds for that long! You all need to make me rich enough to hire an intern to run these tests elsewhere!!!Given the high number of measurement points I was able to increase the "expansion order" which results in error of much less than 1% across the full frequency range.Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker can be used. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:Starting with the good news, the on-axis response is surprisingly flat, resembling some nice studio monitors. There is a peak which based on other measurements I show (and those performed by others) is mostly a tweeter resonance. It is narrow though so not so concerned about it. If you are, you can EQ it out (see listening tests).The other notable bit is the drop in response above 14 kHz and some ringing. I have seen the former from another measurement (GR Research). The ringing doesn't show in theirs but I think that may be due to low resolution of their measurements. Or else, something is rattling in mine that was not in theirs. Alternatively, JBL knows the driver/horn is resonating and put in a filter to roll off the response instead of letting it peak above average.We can see proof of that here when we drive the 530 with a 10 volt input:The sudden peaks definitely show a tweeter that is unhappy at either end of its spectrum.Bass response is a bit tilted down which likely makes for a less satisfying experience. Again, see listening impressions later.Putting all of this together in a hypothetical, average listening room gives us a surprisingly smooth response:Two bads seem to have fixed the crossover resonance peak:The normal vertical dips we get in a 2-way speaker at crossover cancel out the peak on-axis. In that regard, you don't want to put much absorption anywhere although this is not a big enough deal to ignore other factors (e.g. a room that is too live with many bare surfaces).Horizontal directivity paints a very nice picture, pun intended:You have a broad listening angle where response does not change a lot.Vertical is chewed up around the crossover:Here is the waterfall measurements. Unfortunately I ran it with the mic well above listening axis so the response doesn't match the rest of what is above:Finally, we have a typical minimum impedance of 4 ohm:Combine that with sensitivity of around 85 dB and this is not an easy to drive "horn" speaker.I started my listening tests with just the single EQ for my room mode where I place the speakers and sit. Here, the sound was one of the least bright or offensive of any speaker I have tested. There is not a "bright" bone in the body of the JBL 530. That also makes it less exciting to listen to. To give it some oomph and warmth, I dialed in a shelf boost below 200 Hz. That improved subjective experience a lot. But then I put my ear to the port and could easily hear the woofer bottoming out. So be a bit careful in doing this but do experiment.I also put in a notch filter where the resonance point in the crossover. It made a positive difference but I think this was unrelated to that effect as the sound became a bit brighter (in a good way) telling me the Roon PEQ implementation may be ringing outside of the pretty graph shown.For a quick comparison, I loaded the ELAC DBR-62 speaker which I just reviewed . Wow, what a transformation. Bass quality and quantity was so much better. As was detail and overall enjoyment level.While the JBL Studio 530 has some obvious flaws, it is clear that care was put in there to optimize the design for technically good objective performance. Near flat on-axis response and very smooth predicted in-room response is the result. Alas, if you are like me, you want a bit of lipstick on your speaker and more SPL (loudness) capability to really enjoy music. At the retail price of $600, the 530 does not get there and my strong recommendation would be for the ELAC DBR-62. But for $300, if you are open to some EQ and don't shake the wall as much as I like to do, the JBL 530 is fine.Given all of this, I can give my recommendation for JBL 530 studio at its sale price.------------As always, questions, comments, recommendations, etc. are welcome.It rained all night and all day today.Man that is depressing. Need to go online and buy a bunch of stuff to make me happy. Please help contribute to that byusing