JBL LSR305P MKii and Control 1 Pro Monitors Review

[JohnBooty]

G'day to all. First post. Great site. Thanks Amir!
I'm in the process of downsizing our accomodation and our living room can't accommodate multiple components and conventional speakers.
I've looked at a number of in-wall and on-wall speaker systems but haven't been bowled over. These are bulkier than I would like for on-wall use but the compromise may be worthwhile. I would appreciate advice/feedback on how they might perform when wall-mounted and in close proximity to the rear wall.

They're rear-ported, so their bass output is going to vary quite a bit depending on their proximity to the wall.

As a general rule of thumb, you want front-ported speakers for wall-mounting. Unless it's a situation where there's not much expected bass content anyway, like surround speakers.

 

[DarthVince]

They're rear-ported, so their bass output is going to vary quite a bit depending on their proximity to the wall.

As a general rule of thumb, you want front-ported speakers for wall-mounting. Unless it's a situation where there's not much expected bass content anyway, like surround speakers.

Good point. I didn't see the rear ports.

 

[AnalogSteph]

Now I wonder how the JBL 104 compare, at $54 on special.

A set of measurements was posted on German HiFi-Forum about a month ago.
Ehhh...

Looks like the 1.8 kHz XO spec is dead wrong - I'd say more like 4 kHz or so. What seems to be a passive XO may also explain the more moderate hiss level. (Which in my book is acceptable but nothing to write home about either.) I wouldn't be surprised if these had been designed by another team altogether.

I got a set of 104s for the office when they were just out, to replace some 40€ Genius cheapies that I had borrowed (well, hogged would have been the better expression) - I wanted something compact and "plug'n'play". I swear that when I came in after Christmas break, my ears freshly calibrated by a set of Really Good Speakers(R), the highs peak was pretty much dead obvious. They feel really solidly built though and do not have any annoying pops etc., and the only complaint apart from the bit of hiss I've had was poor contact in the power jack that prompted switching the power lead out for another, though even that is still better left alone.

$54 sure beats the 140€ or so that I paid.

Anyway...
I wonder why so many manufacturers of active speakers don't do anything to address the hiss problem. Can't be that hard to include either a series power resistor for the tweeter or a voltage divider ahead of the power amp (depending on where the culprit lies) and increase tweeter channel output level accordingly, now can it? I can't imagine that a 1" tweeter in a waveguide wouldn't be something like 5-10 dB more sensitive than a 5" woofer, not to mention level handling.

 

[SplitTime]

@SplitTime member @pos has the M2 crossover settings here: http://goo.gl/GdfQ7N and as I understand it, virtually identical to the factory settings.

Also member @dallasjustice is using digital XO and Benchmark amps with his M2's: https://www.audiosciencereview.com/...m2-audiolense-digital-crossovers-w-subs.2369/

Thank you very much!

As a side bar, I went down to the local music shop and demo’d several powered monitors. The demo was in a pretty noisy room with poor source material; but I was able to listen to the JBL 305 mk ii and the 308s. I ended up getting a pair of Yamaha HS8 speakers as I subjectively liked the sound of them better - but I figured it would give me something to play around with in a more controlled setting if for no other reason than just to learn. Eventually I will break down and get a much better pair of speakers; but doing some ”relatively” inexpensive research for now, before plunking down perhaps some serious $$$ for speakers, seems prudent.

All of this has be thinking though that perhaps there’s another variable in the research that (at least, as un-educated as I am in this particular field) might be significant... notably, listener’s hearing response relative to the speaker’s frequency response. I note that Toole mentioned that all listeners (skilled listeners, non-skilled listeners) seemed to rank speakers with the same trends (albeit different magnitudes and different consistencies) during blind testing. But did the listeners have generally the same hearing frequency response? I’d suspect they likely did not - so maybe it doesn’t matter as well. That actually seems like as surprising result to me though - one that my simplistic intuition wouldn’t expect.

 

[amirm]

All of this has be thinking though that perhaps there’s another variable in the research that (at least, as un-educated as I am in this particular field) might be significant... notably, listener’s hearing response relative to the speaker’s frequency response. I note that Toole mentioned that all listeners (skilled listeners, non-skilled listeners) seemed to rank speakers with the same trends (albeit different magnitudes and different consistencies) during blind testing. But did the listeners have generally the same hearing frequency response? I’d suspect they likely did not - so maybe it doesn’t matter as well.

I have taken the double blind twice with different set of people in the same event. Both cases my vote for the best sound matched majority of people in the room regardless of age. For their trained listeners, Harman does disqualify people with any kind of hearing impairment/reduced frequency response.

 

[RayDunzl]

Sounds like a typical Trumptard.

*wonders who will become the opposition's candidate

I have taken the double blind twice with different set of people in the same event. Both cases my vote for the best sound matched majority of people in the room regardless of age. For their trained listeners, Harman does disqualify people with any kind of hearing impairment/reduced frequency response.

Are the "untrained" listeners prompted about "what to listen for", "what makes a good speaker", whatever, before their exposure to the contestants?

 

[amirm]

Are the "untrained" listeners prompted about "what to listen for", "what makes a good speaker", whatever, before their exposure to the contestants?

No. These were "dealer training" events run by Harman. First one was 10 to 15 people from different high-end audio dealerships. The second one was "Master ARCOS Training." ARCOS is Harman's Room EQ technology. This was a smaller event with just a few acousticians.

After we were done, we went to the IEC room at Harman and Sean ran his "how to listen" test. Everyone flunked level 2 and higher so definitely "not trained."

 

[sweetchaos]

Try shorting-out the inputs and see if there is a difference. Plug in an input cable(s) and short between the hot pin and shield at the far end.

As requested, I did another set of measurements below in my Room2:

Measurement 1 (red):
Room Noise.
Same test and similar results as yesterday.

Measurement 2 (light blue):
JBL 305p Mkii power cord plugged in.
Nothing plugged into inputs.
Measurement microphone was 0.5in away from tweeter.
Same test and similar results as yesterday.

Measurement 3 (purple):
JBL 305p Mkii power cord plugged in.
XLR to RCA cable plugged in to speaker's input.
Shorted-out the center to shield at far end of RCA cable.
Measurement microphone was 0.5in away from tweeter.
This test was requested.
Results were the same as measurement #2.

I repeated the test several times, for each scenario, with same results.

Overall, *hiss* didn't change, both audibly or in measurements.

Also, thanks for the tip on shorting-out the inputs, i'll keep that in mind for future.

 

[napilopez]

A set of measurements was posted on German HiFi-Forum about a month ago.
Ehhh...

Looks like the 1.8 kHz XO spec is dead wrong - I'd say more like 4 kHz or so. What seems to be a passive XO may also explain the more moderate hiss level. (Which in my book is acceptable but nothing to write home about either.) I wouldn't be surprised if these had been designed by another team altogether.

I got a set of 104s for the office when they were just out, to replace some 40€ Genius cheapies that I had borrowed (well, hogged would have been the better expression) - I wanted something compact and "plug'n'play". I swear that when I came in after Christmas break, my ears freshly calibrated by a set of Really Good Speakers(R), the highs peak was pretty much dead obvious. They feel really solidly built though and do not have any annoying pops etc., and the only complaint apart from the bit of hiss I've had was poor contact in the power jack that prompted switching the power lead out for another, though even that is still better left alone.

$54 sure beats the 140€ or so that I paid.

Anyway...
I wonder why so many manufacturers of active speakers don't do anything to address the hiss problem. Can't be that hard to include either a series power resistor for the tweeter or a voltage divider ahead of the power amp (depending on where the culprit lies) and increase tweeter channel output level accordingly, now can it? I can't imagine that a 1" tweeter in a waveguide wouldn't be something like 5-10 dB more sensitive than a 5" woofer, not to mention level handling.

Huh, I measured the 104 as well a few months ago - I think that member's measurements make the speaker look quite a bit worse than my own.

The on axis curve is similar but their off-axis data looks much worse. I think the 104 is one of those speakers that needs averaging to get a real idea of their sound, since the coaxial driver leads to messiness in the treble that largely balanced out in the listening window. Going to see if I can process the data a bit more to get an ER curve. Also worth mentioning the advantage of the coaxial driver is that these are designed be placed right on a desk with no need to angle (the vertical response is very similar).

 

[Deacon Blues]

YES! More Speaker reviews Amir! Thanks man.

 

[ShiZo]

These are much harder to understand for me compared to dacs and amps lol.

 

[amirm]

These are much harder to understand for me compared to dacs and amps lol.

Read the newer reviews and you will see that they are much simpler to read. This first review was comprehensive to explain the details.

 

[Valentin R]

Thanks Amir

What a great Grown up Toy

Cant wait to see more results on all kinds of speakers

 

[Valentin R]

Amir

could you post the cea 2034 measurements without comments like you did with the kalis
spins and predicted in room response

It would be nice if all of the post be done in the same scale and size so it will be easy to compare

thanks fore sharing

 

[pma]

The Control 1 Pro came with my Klippel NFS speaker measurement system. It is only sold through Pro channel and costs US $164 for a pair.

View attachment 45240

We have quite similar results with JBL Control1 Pro, @amirm . Mine is the passive version, they also produce a model with electronics built in.

Edit: added below is distortion at some 2Vrms. Not bad for such a cheap small plastic box.

 

[LightninBoy]

Little late to the party here, but as an owner of JBL 306mkii thought I'd weigh in ...

* This confirms my subjective impression that the tweater/wave guide on these speakers are really really good. In other speakers in its class, I hear what I call "splashy" highs. Some may call this "detailed", but it always seems artificial to me. Particularly for female vocals. The JBLs though have none of that splash. I've always assumed the splashy highs were just a function of boosted high end frequency response, but I'm beginning to think its a function of messy off axis curves. Therefore, when I saw the JBL on-axis FR measurements (from other sites) that showed a large rise in the high end, I was really surprised. But the listening window curve and DI curves better explains what I'm hearing,
* I hope the 306mkii is measured at some point. I've seen some on-axis FR measurements that would suggest that it measures worse than the 305mkii because the woofer/tweater transition point is not as smooth. Its a really narrow dip though, so I'd be curious to see how that impacts the listening window.
* I use my JBLs in a near-field application on my computer desk and, although there is a hiss, it is not a big issue for me. It is barely audible at all from my desk chair in a silent room and once the computer is on, it is completely drowned out by the computer fans. That said, they replaced cheap 10 year old Tannoy monitors that had zero hiss, so I don't get why there is any hiss at all.
* I do think it would be interesting and useful to measure the electronics within. We've seen amirm review some cheap class D amps that didn't measure well , but are the amps inside this speaker any better?

 

[TLEDDY]

On hiss...

Please tell me the frequency spectrum of hiss. If that is stated somewhere in the previous 21 pages, I apologize because I missed it.

My hearing is gone above 10K, primarily due to complete lack of hearing protection during Army basic training and advanced age. I cannot hear a basket of asps hissing at me, much less high frequency hiss from a tweeter.

*****How about an answer to the above, please. *****

 

[ribosradagast]

*****How about an answer to the above, please. *****

https://www.audiosciencereview.com/...pro-monitors-review.10811/page-22#post-304544
Looks like 1.5khz to 3.5 khz

 

[TLEDDY]

Aha! Thanks!

 

[Thomas_A]

This is a review and detailed measurements of the JBL 305P Mark ii powered studio monitor and Control 1 Pro budget passive monitor. I purchased the 305P Pro Mark ii when it first came out and it currently sells for US $147.50 from Amazon including Prime shipping. This is the price for one so you need to double that for stereo setup. The Control 1 Pro came with my Klippel NFS speaker measurement system. It is only sold through Pro channel and costs US $164 for a pair.

The 305P Mark ii has good heft and feel to it for a budget priced monitor:

View attachment 45226​

Back panel shows the connectivity and configuration:

View attachment 45227​

The Control 1 Pro doesn't feel like junk but not anywhere close to 305P:

View attachment 45228​

Introduction
This being the first measurement of speakers being published using this new measurement system, it will also act as a tutorial on how to read the measurements. What is presented is a small subset of what is captured but it is the most useful one. Going back to early work performed by Dr. Floyd Toole while at Canadian Research Council (NRC) (early 1980s), a collection of measurements are performed around a speaker to better characterize how it might sound in your room. This work has been refined over the years and the latest version is memorialized in standard known as CEA-2034 or CTA-2034. They are for sale publications but if you search enough, you can find online copies.

The standard and research requires that measurements be performed in an anechoic chamber, i.e. a room without any reflections. If you measure in a room, then you impart its signature on the measurements and the data is no longer valid. Anechoic chambers cost from a million dollars and up so outside of realm of all but biggest manufacturers. Fortunately we now have a Klippel NFS system which using an automated system and heavy math can extract anechoic response of a speaker that is measured in a standard room. In my case, that "room" is our three-car garage. The room has large volume and dimensions which helps a bit but still would not be good without the Klippel NFS system.

One great advantage of the Klippel system is that it measures the speaker at close distances and then computes what the measurements would be like at longer distances. CEA-2034 for example requires measurements at 2 (?) meters. That is actually a bit too close to the speaker for large tower speakers (measurements should be performed in "far field"). Not an issue for NFS system since it measures very close (inches from the speaker) and as such, can get very strong signal captured by the microphone. This makes it immune to environment noise which is a great asset as I measure speaker. NFS system generates CEA-2034 compliant curves given their guidelines and requirements so you don't need to understand these differences.

Harman called the measurements that create these results "spinorama" since the microphone was kept constant and the speaker rotated to make individual measurements. The name has stuck so you might as well be familiar with it.

If you want to understand this topic to as much depth as you like, I highly suggest purchasing Dr. Toole's book, Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms: https://www.amazon.com/Sound-Reprod...-Loudspeakers-Engineering-ebook/dp/B074CHY128

CEA-2034 "spinorama" Measurements
The classic set of measurements required for CEA-2034 is 70 as indicated (really 72 but two are duplicates):
View attachment 45229

The Klippel NFS system doesn't work this way. It scans up close and then models what the far field response looks like. It requires more points if you have a more complex speaker or are operating in a small room. For the results you are about to see, 550 or so points were used. I will be refining these measurements more so this may vary. The scan normally takes an hour but I told the system to make multiple measurements and average them. This lengthened the time to two hours but I don't think it did much useful (lowering noise). Fortunately the whole process is automated after setup so I ate dinner and watched a movie while it was doing its thing.

Here is the overview of the system results:

View attachment 45230

The red line shows the on-axis (direction of tweeter) if you did not use the Klippel NFS. It shows a bunch of ups and downs that get worse as you go lower in frequency. These are room reflections (shown in dashed blue) which are interfering with the direct sound. Once these are mathematically removed, we are left with the blue solid line which is now free of room variations.

The vertical dashed line delineates a different technique for getting reflections which is to cut off the measurement after certain time. If you do this right, you can capture just the direct sound. Alas, using a short window of time means that you lose low frequency information. So this technique does NOT work for low frequencies and you need another method. Here, we are letting NFS system solve that problem for us.

None of this is important with respect to understanding of the speaker measurements. So stay with me.

Overall and On-axis Response
When measuring speakers, you select a an acoustic center which is typically a line perpendicular to the tweeter. Keep that in mind and now let's look at this series of curves:

View attachment 45231

Amir, how can the near-field response be almost similar to the far-field response in terms of woofer output in relation to tweeter? (If I understand the graphs correctly.)