This is a review and detailed measurements of the JBL SRX835P "PA/DJ" powered speaker. It is on kind loan from a member and costs US $1,699.
Note: our company, Madrona Digital is a dealer for Harman and hence JBL line. So feel free to read whatever bias you feel necessary in my subjective commentary.
This is a monster of a speaker and it is still sitting on top of the Klippel NFS measurement system:
I like their sense of humor:
"Easy portability" and 85 pounds don't go in the same sentence in my book! Still, it has nice set of handles on each side which is more than I can say for consumer speakers.
Lots of controls are provided in the back although for anything meaningful you need their app:
The app lets you program up to 20 parametric EQs which is very nice. It also has test signal generation.
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. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber. In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.
I performed over 1000 measurement which resulted in error rate of about 1% to about 8 kHz. Above that due to tweeter going crazy, the sound field becomes very complex and accuracy gets lost above 10 kHz or so.
Reference axis is approximately the center of the tweeter. I could barely see its outline by shining light through the grill so may not be exact.
JBL SRX 835P Measurements
Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker is and how it can be used in a room. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:
OK, what the heck is this??? Why is there a shelf at 500 Hz? I was doubting my measurements until @MZKM pointed me to their own spec sheet:
Heavy filtering in JBL graph erases a lot of sins but still shows the same shelving. It is because there is no bass reinforcement in outdoor use so they have found that they need to juice up that area out of box? Why not use a few of the filters and have an out of box flatter response?
Whether it is caused by the grill or the tweeter (or both), the response goes crazy above 9 kHz. I am not sure what is causing the dip at 139 Hz. You can see another version of in the near-field measurements:
Why is the mid-range response tilting down that way so early? Note that the crossover between the midrange and tweeter is passive so maybe it is too low of an order?
The tweeter is beyond redemption at this level of magnification. Again, some of this could be due to the grill.
Our early window and predicted in-room response are for ordinary use of this speaker indoor which I am not sure is very applicable:
Our waterfall plot shows a number of resonances:
My pick of 1000 to 3000 Hz directivity plot happens to be in the region where the speaker is more well behaved:
Distortion is quite low at 86 dBSPL as one would hope to see:
The tweeter though remains unhappy:
Directivity is very narrow by our consumer standards but matches company advertising:
Here is vertical:
That is seriously narrow which I suspect is on purpose due to far distances people sit from it and need to conserve power.
As I noted, the speaker is still on the stand so no opportunity to listen to it. Owner says it can get loud, seriously loud, and I believe him.
EDIT: I took the time to listen to the speaker now.
Listening Test and Equalization
Speaker was too heavy to haul into my normal listening room. So I tried something new: setup a new station in my "lab" (very large garage) to listen to the speaker. I took it down using my lift so I decided to leave it on that so I could elevate it to any height. This turned out to be important. Speaker is in the center of this very large space which is filled with huge number of boxes and such, providing for rather normal reverberation time. The large volume always helps with room modes, pushing them lower in frequency and hence less bothersome.
At first I had the speaker aligned with the tweeter at ear height. Instant impression was "hey, this thing sounds good!' A few instances later, "but boy this tweeter can be sharp!" I brought out my EQ tool and tried to tailor the highs but without a lot of success. So I took advantage of my lift and raised the height so that the mid-range was at ear height. This did the trick together with a few filters:
I must say, I was not ready for the incredibly positive experience this speaker plus above EQ provided. The sound was clean, clean and dynamic. Without the EQ the bass and highs were emphasized. With the EQ in place, the sound was just sublime in that I could turn up the level really high and the speaker kept scaling up. At elevated volumes, I could then hear a lot more detail that I would often not hear in my tracks.
I have built a large playlist with sub-bass content I use for headphone testing. Usually they stress speakers too much so I only use them sparingly there. Man, where they made for the JBL SRX835P. The experience of hearing these tracks with this speaker, in this space was transformative! It was that good!
You don't believe me? Here is the wife evidence. Half-way through the testing my wife came into the garage. I expected an complaint about the sound level. What transpired was an impromptu dance session to what I was playing then, the famous Steely Dan's My Cousin Dupree:
Except for my Salon 2 speakers, I don't find this track to be hugely enjoyable. But boy, where they the case here. Every track in my headphone playlist sounded superb.
I think what is going on here is that smaller speakers must be increasing in distortion rapidly, causing one to not turn them up. And if you don't turn them up, then you don't enjoy the full dynamics and details in your music.
On directivity, the highs are extremely directional. At my listening distance of 7 to 10 feet, you have a few feet after which the highs drop off. Without EQ, this is not a bad thing as it removes the sharp highs. Interestingly, with EQ, the mid-range is more in charge and provides a wider dispersion and a much more more normal listening width.
Note that the tweeter generates hiss. It was audible in my space to about 3 feet. At my normal listening distance, it was not audible at all.
I cranked the speaker to max volume and even then, there was no hint of stress and distortion. I remember the now departed Greg Timbers of JBL bad mouthing Revel Speakers as being good enough for elevator music. As much as I disagree with him, I think in contrast to these types of JBL speakers, he may have a point. I had a similar epiphany when I listened to the JBL 708P and 4349.
It was an interesting sensation to have frequencies above bass cause physical vibrations in you body!
Yes, listening at these levels for too long is not good for your hearing. But a few minutes of it put a smile on my face that I can't yet wipe.
Conclusions
Measurements show a clearly imperfect speaker here. I am fine with the company saying this thing gets used in venues and such and gets beat up good. My question is why not use the internal DSP and give us a few filters that linearize its frequency response? The heavily smoothed graph portrays a far better picture of the speaker than it deserves. So personally I am quite unhappy to see this situation.
EDIT: I have changed my recommendation post listening tests.
I can't recommend the JBL SRX 835P without equalization. With equalization however, it becomes a highly dynamic and capable speaker and gets my recommendation. You have not lived until you experience a speaker with such high dynamics.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
Note: our company, Madrona Digital is a dealer for Harman and hence JBL line. So feel free to read whatever bias you feel necessary in my subjective commentary.
This is a monster of a speaker and it is still sitting on top of the Klippel NFS measurement system:
I like their sense of humor:
"Easy portability" and 85 pounds don't go in the same sentence in my book! Still, it has nice set of handles on each side which is more than I can say for consumer speakers.
Lots of controls are provided in the back although for anything meaningful you need their app:

The app lets you program up to 20 parametric EQs which is very nice. It also has test signal generation.
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. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber. In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.
I performed over 1000 measurement which resulted in error rate of about 1% to about 8 kHz. Above that due to tweeter going crazy, the sound field becomes very complex and accuracy gets lost above 10 kHz or so.
Reference axis is approximately the center of the tweeter. I could barely see its outline by shining light through the grill so may not be exact.
JBL SRX 835P Measurements
Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker is and how it can be used in a room. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:
OK, what the heck is this??? Why is there a shelf at 500 Hz? I was doubting my measurements until @MZKM pointed me to their own spec sheet:
Heavy filtering in JBL graph erases a lot of sins but still shows the same shelving. It is because there is no bass reinforcement in outdoor use so they have found that they need to juice up that area out of box? Why not use a few of the filters and have an out of box flatter response?
Whether it is caused by the grill or the tweeter (or both), the response goes crazy above 9 kHz. I am not sure what is causing the dip at 139 Hz. You can see another version of in the near-field measurements:
Why is the mid-range response tilting down that way so early? Note that the crossover between the midrange and tweeter is passive so maybe it is too low of an order?
The tweeter is beyond redemption at this level of magnification. Again, some of this could be due to the grill.
Our early window and predicted in-room response are for ordinary use of this speaker indoor which I am not sure is very applicable:
Our waterfall plot shows a number of resonances:
My pick of 1000 to 3000 Hz directivity plot happens to be in the region where the speaker is more well behaved:
Distortion is quite low at 86 dBSPL as one would hope to see:
The tweeter though remains unhappy:
Directivity is very narrow by our consumer standards but matches company advertising:
Here is vertical:
That is seriously narrow which I suspect is on purpose due to far distances people sit from it and need to conserve power.
As I noted, the speaker is still on the stand so no opportunity to listen to it. Owner says it can get loud, seriously loud, and I believe him.
EDIT: I took the time to listen to the speaker now.
Listening Test and Equalization
Speaker was too heavy to haul into my normal listening room. So I tried something new: setup a new station in my "lab" (very large garage) to listen to the speaker. I took it down using my lift so I decided to leave it on that so I could elevate it to any height. This turned out to be important. Speaker is in the center of this very large space which is filled with huge number of boxes and such, providing for rather normal reverberation time. The large volume always helps with room modes, pushing them lower in frequency and hence less bothersome.
At first I had the speaker aligned with the tweeter at ear height. Instant impression was "hey, this thing sounds good!' A few instances later, "but boy this tweeter can be sharp!" I brought out my EQ tool and tried to tailor the highs but without a lot of success. So I took advantage of my lift and raised the height so that the mid-range was at ear height. This did the trick together with a few filters:
I must say, I was not ready for the incredibly positive experience this speaker plus above EQ provided. The sound was clean, clean and dynamic. Without the EQ the bass and highs were emphasized. With the EQ in place, the sound was just sublime in that I could turn up the level really high and the speaker kept scaling up. At elevated volumes, I could then hear a lot more detail that I would often not hear in my tracks.
I have built a large playlist with sub-bass content I use for headphone testing. Usually they stress speakers too much so I only use them sparingly there. Man, where they made for the JBL SRX835P. The experience of hearing these tracks with this speaker, in this space was transformative! It was that good!
You don't believe me? Here is the wife evidence. Half-way through the testing my wife came into the garage. I expected an complaint about the sound level. What transpired was an impromptu dance session to what I was playing then, the famous Steely Dan's My Cousin Dupree:
Except for my Salon 2 speakers, I don't find this track to be hugely enjoyable. But boy, where they the case here. Every track in my headphone playlist sounded superb.
I think what is going on here is that smaller speakers must be increasing in distortion rapidly, causing one to not turn them up. And if you don't turn them up, then you don't enjoy the full dynamics and details in your music.
On directivity, the highs are extremely directional. At my listening distance of 7 to 10 feet, you have a few feet after which the highs drop off. Without EQ, this is not a bad thing as it removes the sharp highs. Interestingly, with EQ, the mid-range is more in charge and provides a wider dispersion and a much more more normal listening width.
Note that the tweeter generates hiss. It was audible in my space to about 3 feet. At my normal listening distance, it was not audible at all.
I cranked the speaker to max volume and even then, there was no hint of stress and distortion. I remember the now departed Greg Timbers of JBL bad mouthing Revel Speakers as being good enough for elevator music. As much as I disagree with him, I think in contrast to these types of JBL speakers, he may have a point. I had a similar epiphany when I listened to the JBL 708P and 4349.
It was an interesting sensation to have frequencies above bass cause physical vibrations in you body!
Conclusions
Measurements show a clearly imperfect speaker here. I am fine with the company saying this thing gets used in venues and such and gets beat up good. My question is why not use the internal DSP and give us a few filters that linearize its frequency response? The heavily smoothed graph portrays a far better picture of the speaker than it deserves. So personally I am quite unhappy to see this situation.
EDIT: I have changed my recommendation post listening tests.
I can't recommend the JBL SRX 835P without equalization. With equalization however, it becomes a highly dynamic and capable speaker and gets my recommendation. You have not lived until you experience a speaker with such high dynamics.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
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