JBL 308P MKII Studio Monitor Review

[IVX]

So, If I understand well, this JBL is not to use as near monitor because there is a lot of hiss
But also not as far monitor because the power is limited .

Very few use cases where this monitor is adapted for , no ?

I found that little review

https://www.reddit.com/r/audiophile/comments/acmi4e

 

[hege]

Adam once made a floor stander (Tensor Beta), don't know the price (probably high). It's no longer available.

They had many floorstanders... Classic Column... Artist 6... probably pro market is much more lucrative...

 

[infinitesymphony]

I agree DSP crossover is cheaper and can be better but still questioning if this 308P features A-to-D inside.

Still looking around the web for confirmation but can't find anything.

Different story with 708P of course.

I would not be surprised if all future powered speakers use ADC and DSP. We're at the point where even the $99 Edifier R1280T uses a Burr-Brown ADC before hitting a TI digital amp chip with DSP.

What puzzles me about these manufacturers of cheap high-quality monitors is why they do not make a prettier 3-way floorstander version of them and go to annihilate the hi-fi market at 1200 bucks a pair. Maybe jbl would cannibalize sister brands, while genelec or adam wouldn't.
Anyone knows why?

A passive floorstanding version of these could be interesting because you could potentially get higher volume and lower distortion (maybe even with the same cheap drivers if using more than one?), but it seems like that would require the DSP to be implemented differently if it's even possible because the signal would already be at speaker level.

But generally speaking, the floorstanding market is much smaller than the bookshelf and studio markets, and the studio market wants to place the bass in an optimal position using subwoofers.

 

[infinitesymphony]

So, we have the JBL 30x series and the Adam TxV competing for best active monitors in the ~$400-600/pair range.

Whither Yamaha HSx and Mackie MRx24?

 

[Deleted member 2944]

I wonder if one could measure signal sent to woofers and HF (to determine crossover characteristic) so 305/308 could be converted into proper good monitors using external crossover amps without rubbish hiss.

That's possible with any of these active monitor speakers. A differential measurement between input and the speaker terminals can characterize the transfer function required. (The latency would need to be understood and removed.)

It can get a little tricky making these measurements because the speaker terminals might be floating relative to the ground within the amplifier setup. But it's not something that can't be worked around.

Dave.

 

[richard12511]

Sure, I get that. But it should also be a concern when design a speaker. Maybe less so for a monitor, but they have the same offputting design on the 5XX series as well. No one likes an eyesore.

Personally I find this speaker to be quite beautiful. In particular, love the shape of the waveguide. I also own the JBL 530, and I agree with you there. That is an ugly speaker, especially if you take the grill off .

 

[richard12511]

This better product exists (JBL 708).

For much more money, so not really.

 

[richard12511]

What I find interesting and somehow also strange for a giant like Harman is that it is tuned much more linearly than the here tested 305P MKII and thus en par to the other JBL active monitors and also the first 30x generation, only needs maybe -1db high shelf filter, can't understand what went wrong with the 305P MKII.
The only thing I find disappointing in this is the over 1% distortion at a very wide and audible band between 1-2 kHz which probably shows the limits of a low cost woofer, at least it is the more good-natured 2nd harmonic.

Agreed. This review really has me wondering what went wrong with the 305p.

 

[SpaceMonkey]

That's possible with any of these active monitor speakers. A differential measurement between input and the speaker terminals can characterize the transfer function required. (The latency would need to be understood and removed.)

It can get a little tricky making these measurements because the speaker terminals might be floating relative to the ground within the amplifier setup. But it's not something that can't be worked around.

Dave.

I think Behringer CX2310 Super X Pro V2 + a cheap used Denon receiver with multichannel input will do the trick and wont break the budget.
S/N on Behringer seems quite ok for an analog crossover:

 

[richard12511]

Sorry for my bad, it seems it’s playing at the level of accuracy as the 8030s at half the price ?

Also much more distortion. I've got both here, and the 8030c does sound better(imo).

 

[Pearljam5000]

So, we have the JBL 30x series and the Adam TxV competing for best active monitors in the ~$400-600/pair range.

Whither Yamaha HSx and Mackie MRx24?

Also focal Alpha

 

[Deleted member 2944]

I think Behringer CX2310 Super X Pro V2 + a cheap used Denon receiver with multichannel input will do the trick and wont break the budget.
S/N on Behringer seems quite ok for an analog crossover:
View attachment 92098

No, that's a primitive crossover with no equalization capability. I have one of those CX2310 units sitting on my equipment rack. It's pretty much useless. You can have it if you want it.

Most likely, at least a few bands of PEQ (for each driver) would be required.

Dave.

 

[richard12511]

For people wondering about this vs the Adam/Mackie/708p/8030c, I think it's important to stress the price difference. If one is willing to wait a few months, these are essentially $300/pair monitors(that's what I paid for them, as well). For $300/pair, these things are one of the best values we've seen. Yes, they do have issues. That distortion is most likely audible(guessing), and the hiss is a deal breaker for some, but again...$300/pair.

Does Adam run sales like JBL? I don't follow their site as well as I do Harman's. If you can wait for the inevitable Harman sale, the 308p is half the price of the T8V(not on sale), and shows better objective performance.

@Tangband's idea of improving the cabinet has me interested. I'm not sure I agree that the cheap cabinet is the cause of the high distortion, but perhaps better bracing might still be of some benefit? These do feel very cheap. My first reaction when picking them up for the first time was "wow! these are way lighter than I was expecting", pretty much the opposite of the reaction I had when I picked up the 8030c for the first time .

 

[SpaceMonkey]

No, that's a primitive crossover with no equalization capability. I have one of those CX2310 units sitting on my equipment rack. It's pretty much useless. You can have it if you want it.

Most likely, at least a few bands of PEQ (for each driver) would be required.

Dave.

Just still tried being in super budget/analog mode. DCX2496 is a natural choice here as minidsp 2x4 and 2x4hd seem to be rather poor in analog/digital terms.

 

[stevenswall]

Hopefully we find such a beast as we keep testing. We are so close....

Need to test a Phantom! Other companies are years out from something that compares as a package when it comes to dispersion, bass extension, and even response. If they made a non-app version with regular inputs and let users adjust the bass tilt, I'd put it up there as a Genelec 8260 alternative.

 

[IVX]

Actually, it is not a big deal to test the noise of the monitor's tweeter from 1" distance, at least to compare with others. A decent power amp has SNR >110db, and technically t is a trivial task, of course, need to use at least $1 opamps and $3 ADCs but that's so sweet to save money with dirty-cheap parts like njm4558 25pcs/$1 and CS5340 for $1/2 + STA350 for $1

 

[SpaceMonkey]

Anyone measured drivers themselves(and their distortion) and the waveguide?

 

[infinitesymphony]

Actually, it is not a big deal to test the noise of the monitor's tweeter from 1" distance, at least to compare with others.

Agreed, I think this could be a useful metric for those sensitive to hiss, along with maybe a FR chart of the noise.

 

[RayDunzl]

Well, all the data in the attached Spinorama text file that Amir attached is at 110dB, so I'm thinking we can just use that data directly for EQ purposes without any "normalisation".

Within their normal range, I haven't seen speakers change their response curve

Measuring in-room, at level too low, the ambient noise will intrude on the low frequency measurements, so, don't go too low.

Here is a set of measurements fom about 45 to 93dB, with 2db intervals in SPL, in-room.

You can see the confusion at low SPL (bottom left) where ambient noise intrudes on the low frequency measures. From 70dB on up, the traces match despite increasing SPL

 

[richard12511]

Can you describe the difference?

To my ears, the Genelec sounds cleaner/clearer, and throws a tighter center image. The Genelec is also the "bigger" sounding speaker when I close my eyes(I know this is a question you've asked in the past). Genelec also sounds ever so slightly more tonally correct to my ears, but it's not a huge difference.