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JBL SRX835P Reviewed (Powered Monitor)

sarumbear

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So dynamic capability has been identified as important but is missing from the current test regime. Extra work and possibly software/hardware but could something like: https://m-noise.org/ be added to the test suite?
This is a great idea. I hope @amirm agrees.
 

drplinker

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So dynamic capability has been identified as important but is missing from the current test regime. Extra work and possibly software/hardware but could something like: https://m-noise.org/ be added to the test suite?
Yes, would be nice include this test in measurement regime.

After quick glance if I got it right, M-noise replicates tonality of music and appears to measure mainly HF capabilities - how much and how well it handles output power surge and recovery.

I may be wrong, but my understanding of speaker's dynamic capability is how well it can reproduce an quieter instrument (example) played at the same time as another loud instrument. Or say someone whispering while loud drums are playing. And without increasing the output to high enough level, the whisper would cannot be heard. And @amirm is pointing out in listening test of this speaker is that increasing volume on smaller speakers to high enough level to hear such whispering will introduce distortion in drums, however this speaker can deliver both whispering and drums without adding distortion.

If my understanding is right, then it unclear how m-noise is measuring dynamic capability. Are there better tests?
 

jones

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It just struck me that we are dealing with aktive speakers.
Maybe there are different firmware versions at play?

For example, DBtechnologies recently has redone the tuning of the whole Vio Series.

I can't find any changelogs for JBL firmware.
Maybe sombody knows something here?
 

bobster

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seeing some of the QSC speakers measured would be nice - seems like the dj community has really coalesced around QSC gear.

Not just DJs. Keyboardists use them too - I'm one of them, with a pair of K10 (original version). A colleague who plays keys with a major touring rock act was (and maybe still is) and endorser of the K-series.

I'd be curious to see how they measure.
 

kyle_neuron

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Yes, would be nice include this test in measurement regime.

After quick glance if I got it right, M-noise replicates tonality of music and appears to measure mainly HF capabilities - how much and how well it handles output power surge and recovery.

I may be wrong, but my understanding of speaker's dynamic capability is how well it can reproduce an quieter instrument (example) played at the same time as another loud instrument. Or say someone whispering while loud drums are playing. And without increasing the output to high enough level, the whisper would cannot be heard. And @amirm is pointing out in listening test of this speaker is that increasing volume on smaller speakers to high enough level to hear such whispering will introduce distortion in drums, however this speaker can deliver both whispering and drums without adding distortion.

If my understanding is right, then it unclear how m-noise is measuring dynamic capability. Are there better tests?

M-Noise is a pink noise test signal with >16 dB crest factor in the high frequency area, which more closely represents a broad sample of music that was analysed as part of the process.

By using their suggested testing method, you find the peak output SPL where the speaker becomes noticeably non-linear. That's a useful metric because it gives you the maximum level you're likely to want to listen to the thing.

Comparing this against a typical listening level or stated 2.83 V sensitivity metric gives your dynamic range value.

There's work being done to make this an AES standard, so it clearly has some benefit. In my experience the results of the test can be very telling, but you do need a true 96 KHz capable audio interface and mic that doesn't distort early (ruling out the typical cheaper MEMS mics) to conduct the test properly for many pro audio speakers. I've measured >137 dB linear peak SPL on some of the boxes we use, for example.
 

Kouioui

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This thread has been great reading for understanding why dynamics play such an important role in a speaker. I recently performed with a 4pc band at an upscale 70th birthday party at an opulent home, trying to recreate live those hits from the decade through a SRX series setup that included the reviewed unit with subs. Our stage was next to an outdoor pool, so I was able to listen to them without a room piling on its issues.

My impression was fairly positive at making the pre-show 70s music sound as though a real band was performing. I clearly don't have the same engineering and design chops as those posting here, but this 65 year old had a great time listening to these JBLs in a real world situation.

More audiophiles should consider pro portable live sound gear at whatever price they could afford in a home speaker, if there are no objections to the aesthetics of them in a home. For instance, I use both JBL LSR305/310S nearfields and a full JBL IRX portable PA rig in my project studio. For the $1500 I spent for the complete IRX 2.2 system (with poles), I doubt the usual speakers sold for home use at the same price could make people want to DANCE as a speaker system with adequate dynamics can.

PEQ @ 83dB makes the LSR/IRX measurement graphs come quite close after being calibrated with a UMIK-1, REW, and APOeq. My clients would rather hear their final mix on the IRXs 99% of the time, as most of them have hearing loss from the constant exposure to elevated volumes. There's something to be said for trying to reproduce what a live band would sound like in a private residence.
 

kyle_neuron

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For anyone who would be happy with a powered, plastic PA speaker in their house but was a little disappointed with the results from this JBL, may I suggest having a look at the new RCF ART 945?

Here's some independent data from the Production Partner magazine in Germany. Forgive the tiny screenshots, I only get the digital edition due to needing to translate most of it. My high school German is very, very rusty :)

Most of the magazine’s data is measured by a very skilled engineer, Anselm Goertz, using a robot arm for 360-degree balloon generation in a hemi-anechoic chamber.
 

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tktran303

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Apart from the top octave that RCF speaker would EQ very well.

For professional musicians (that is; those whose job relies on the sweat and tears of live performance) who know- whatever venue one is performing in, is a constant variable in live audio; so processing is needed; even for the perfectly neutral speaker…

But it is a narrow dispersion speaker and looks awfully utilitarian in a typical living room. Nice outdoor speaker for your weekend parties…
 
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kyle_neuron

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But it is a narrow dispersion speaker and looks awfully utilitarian in a typical living room. Nice outdoor speaker for your weekend parties…
I don’t class a nominal dispersion of 80-90 degrees from 500 Hz up as narrow, myself? The orange to yellow transition is the -6 dB division on those isobar plots.
 

More Dynamics Please

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It's really great to be seeing some measurements of pro gear, even more so after reading Amir's listening test here. Like mentioned in the thread, seeing some of the QSC speakers measured would be nice - seems like the dj community has really coalesced around QSC gear.

Another PA speaker that would be really interesting to measure is RCF's new ART 9 series which (marketing wise) promises better sound with modern things like waveguides and DSP.

https://audioxpress.com/news/rcf-ce...-active-speaker-series-with-new-art-9-designs

RCF's new ART 9 series does sound interesting. Haven't seen any measurements yet but did find a German review that's reasonably positive:

 

DLxP

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I wonder how well the passive SRX815 would perform in @amirm 's tests. The spec sheet measurements certainly indicate they'd have a tidier FR.

Here's the SRX835P again:

1643056523628.png


And here's the passive SRX815:

1643056443740.png


That looks like +/- 1dB from 400Hz to ~12kHz, although lots of smoothing.

It has the same CD as the 835, so I'd imagine the HF performance would be similar to the results in the test. But I'd bet quite a lot of that >9kHz mess was caused by those heavy duty grilles.

As I think I saw @mitchco point out, the CD in these is the same as in the JBL 4722. A lot of people replace those in the 4722 with a Be CD (replacing the stock CD with the 2435HPL, I think). I wonder if that could be done with the SRX815, without having to mess with the crossover? If that's the case, then the SRX815 used without the grilles + the 2435HPL could make for a killer high SPL passive speaker, at 95dB sensitivity, with max SPL 136dB.
 

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eddy555

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I can affirm that most pa grilles cause pronounced response diffraction. here's an example of a CD driver in a cab with (purple) and without(yellow) the grille
 

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Energy

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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:

View attachment 143933

I like their sense of humor:
View attachment 143935

"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:

800-series-back-panel.jpg


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:

View attachment 143936

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:

View attachment 143937

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:

View attachment 143938

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:

View attachment 143939

View attachment 143940

Our waterfall plot shows a number of resonances:

View attachment 143942

My pick of 1000 to 3000 Hz directivity plot happens to be in the region where the speaker is more well behaved:

View attachment 143943

Distortion is quite low at 86 dBSPL as one would hope to see:

View attachment 143944

The tweeter though remains unhappy:

View attachment 143945

Directivity is very narrow by our consumer standards but matches company advertising:

View attachment 143946


View attachment 143948

Here is vertical:

View attachment 143947

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:

View attachment 144175

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/
Hi, thanks for doing this review I found it very interesting. I have read both good and bad reviews for this speaker and watched only one video review did you manage to get the speaker in your room to listen??
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:

View attachment 143933

I like their sense of humor:
View attachment 143935

"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:

800-series-back-panel.jpg


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:

View attachment 143936

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:

View attachment 143937

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:

View attachment 143938

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:

View attachment 143939

View attachment 143940

Our waterfall plot shows a number of resonances:

View attachment 143942

My pick of 1000 to 3000 Hz directivity plot happens to be in the region where the speaker is more well behaved:

View attachment 143943

Distortion is quite low at 86 dBSPL as one would hope to see:

View attachment 143944

The tweeter though remains unhappy:

View attachment 143945

Directivity is very narrow by our consumer standards but matches company advertising:

View attachment 143946


View attachment 143948

Here is vertical:

View attachment 143947

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:

View attachment 144175

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/
Hi, thanks for the review, I found it very interesting nice to know you can custom the sound on these.
I am considering buying a pair of for DJ use and home listening and was wanting to find an Independent opinion on these speakers before I commit to them, as they are quite expensive £1,600 a piece U.K. retail.
I watched the below review which is the only one around at the moment on YouTube

Did you manage to get the speaker upstairs to your room for a listen?
 

Energy

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I briefly owned these speakers as “floorstanders” in a 4x5m room. The “chest thump” and in-room bass extension to the mid 30hz range was great, but two things killed the experience for me. The hiss is unbearable at 2-3m listening distance (a bit louder than the JBL 305p), and the amp has a cooling fan that kicks in and makes a very audible and annoying hum during listening sessions.

I took some REW measurements and will try to dig them off my old hard drive.
Guy on here
says he heard no hiss from the highs. Could you possibly have a faulty unit? Have you sorted the hiss issue out?
 

drplinker

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Guy on here
says he heard no hiss from the highs. Could you possibly have a faulty unit? Have you sorted the hiss issue out?
The hiss is present, audible within 6ft ~ 10ft. My JBL835P went into protection mode (after connecting 4Volt XLR, but selecting input level as 2Volt consumer). JBL replaced the plate amplifier for free and exact hiss is present, even on new amp.
 
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