I tried without the grill but ended up not liking it and put them back.
Its easy enough to put them back, you just gotta be careful when removing it because it bends easily.
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JBL 708P Review (Professional Monitor)
- Thread starter amirm
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I tried without the grill but ended up not liking it and put them back.
Its easy enough to put them back, you just gotta be careful when removing it because it bends easily.
Question for you more knowledgeable than I, I feel like my 3 LCRs, which are all 708p's, sound slightly different from each other. At first I thought it was the room, but then I put them all in the same location and listened back to back. I guess it could be placebo, but I could swear they all 3 sounded slightly different in the high frequencies, one was particularly noticeable as sounding harsh at the same volume while the others did not. When measuring, the frequency response looked awfully similar though. But I can't really unhear it. The speaker I use as my center channel has slightly more high frequency presence, the right speaker has less, and the left speaker sounds just right to my ears. I feel like they are almost different enough that it would cause me to make different decisions in an EQ/mastering situation based on which speaker the sounds were coming out of.
Even my 2 705p's sounded slightly different to each other. I tested my father's 308p in the same position and I couldn't tell them apart really at all. So what gives? Obviously I know there's some variation speaker to speaker, but I would expect less in the 7 series than the 3 series. I did purchase my 708s and 705s B-stock back in 2019.. maybe b-stock was a bad idea
Could it be variations in the internal crossover? Just wondering how they could measure similarly but sound noticeably different.(I'm not too knowledgeable on speaker design/science)
Even my wife could tell, and she's not exactly an audio engineer.
Thinking about buying a new 708 to compare as a reference point.
Even my 2 705p's sounded slightly different to each other. I tested my father's 308p in the same position and I couldn't tell them apart really at all. So what gives? Obviously I know there's some variation speaker to speaker, but I would expect less in the 7 series than the 3 series. I did purchase my 708s and 705s B-stock back in 2019.. maybe b-stock was a bad idea
Could it be variations in the internal crossover? Just wondering how they could measure similarly but sound noticeably different.(I'm not too knowledgeable on speaker design/science)
Even my wife could tell, and she's not exactly an audio engineer.
Thinking about buying a new 708 to compare as a reference point.
You can't really "in the same location" and "listen back to back" at the same time since even putting two speakers right beside each other can have different result, and if you have to shift the speakers before each listen it's no longer back to back.
Just randomly swap the speakers every few days and use them normally. If it is room or the speaker, you would know.
For the record, my TV speakers have one side already having a messed up tweeter, only discovered when I decided to measure the speakers for the record. I continue using the speakers since I am not bothered by the difference.
Do remember to reset your 708p if they were returned from a previous user.
Just randomly swap the speakers every few days and use them normally. If it is room or the speaker, you would know.
For the record, my TV speakers have one side already having a messed up tweeter, only discovered when I decided to measure the speakers for the record. I continue using the speakers since I am not bothered by the difference.
Do remember to reset your 708p if they were returned from a previous user.
staticV3
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No use theorizing about a potentially nonexistent problem.
First make sure that there actually is a problem.
If your regular in-room measurements don't show anything, try close-mic'd, gated measurements to isolate the tweeters' inherent response without room acoustics.
That's true. I marked out tape in the location and got them to as close as the same position as a possible, but it did take at least 30 seconds to swap the speakers. I forget where I read our auditory memory is like 14 seconds or something like that. I did factory reset, yes.
Sure, I just also contacted JBL technical support and that's the only thing they thought it might be, the crossovers. They also said they couldn't obviously know for sure without testing them. I'm debating sending them in, as it's $395 a speaker, for them to potentially say they're within tolerances. I will mention I have a heavily treated room, so it is more revealing than most.(Minimum 17" thick on walls, 10"-14" thick on ceiling, combination of broadband and membrane based low-frequency absorption)
The other thing that's potentially relevant, is I recently moved. 2 of the speakers, 1 708p, 1 705p, I was able to package in the original boxes, but those were all I had. So I entrusted the movers to box the other 3 speakers, big mistake. Despite stressing multiple times, they ended up packing the wrong speakers and the JBLs ended up all scratched and scuffed when I found them. They don't have any cabinet dents, and I assumed they were fine, but to be honest, I don't know what all they went through. I'm sure they were exposed to high temperature as the move was over the summer as well. Anyhow, deep regret.
The JBL tech support said they're extremely durable though, so didn't think that was an issue. (I know someone on here mentioned their cat knocked their 708 off their desk and it still survived. Impressive)
Helpful suggestions, thank you. Reading up on gated measurements now.
Sure, I just also contacted JBL technical support and that's the only thing they thought it might be, the crossovers. They also said they couldn't obviously know for sure without testing them. I'm debating sending them in, as it's $395 a speaker, for them to potentially say they're within tolerances. I will mention I have a heavily treated room, so it is more revealing than most.(Minimum 17" thick on walls, 10"-14" thick on ceiling, combination of broadband and membrane based low-frequency absorption)
The other thing that's potentially relevant, is I recently moved. 2 of the speakers, 1 708p, 1 705p, I was able to package in the original boxes, but those were all I had. So I entrusted the movers to box the other 3 speakers, big mistake. Despite stressing multiple times, they ended up packing the wrong speakers and the JBLs ended up all scratched and scuffed when I found them. They don't have any cabinet dents, and I assumed they were fine, but to be honest, I don't know what all they went through. I'm sure they were exposed to high temperature as the move was over the summer as well. Anyhow, deep regret.
The JBL tech support said they're extremely durable though, so didn't think that was an issue. (I know someone on here mentioned their cat knocked their 708 off their desk and it still survived. Impressive)
Helpful suggestions, thank you. Reading up on gated measurements now.
Even though these are really expensive reference level speakers they are still mass-produced and it could be possible for the compression driver fit to be different into the horn. It would not take much for there to be a (normally) slight difference. Your room is well-treated so it might be easier for you to spot, however, you can't completely disregard the power of placebo.
If you could do an EQ slightly lower on the treble frequency on the rough-sounding speaker, I believe it would mesh better. I know you know thi,s but don't make the problematic speaker your center. The center channel in home theater is the most critical channel the way media is mixed.
(If these were the 3 series I would say it is not worth sending into JBL. It might be worth a service on the 7 series, however since a lot of recording studios and film sound mixing occur on these and they have a vested interest in keeping these speakers to a tighter spec. Genelec can hit between the numbers and that is who they are competing with on the 7 series.)
If you could do an EQ slightly lower on the treble frequency on the rough-sounding speaker, I believe it would mesh better. I know you know thi,s but don't make the problematic speaker your center. The center channel in home theater is the most critical channel the way media is mixed.
(If these were the 3 series I would say it is not worth sending into JBL. It might be worth a service on the 7 series, however since a lot of recording studios and film sound mixing occur on these and they have a vested interest in keeping these speakers to a tighter spec. Genelec can hit between the numbers and that is who they are competing with on the 7 series.)
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There have been reports of inconsistent quality control. I would first spend the money on a UMIK-2 and take some measurements. Can figure out whether you have one bad speaker or two. Maybe the different one is flat and it’s the other two which are broken? Maybe it’s just a room effect.
Um, that seems rather contradictory? These look very good but I want something I can really crank hard rock/metal without the usual has of distortion coming in...would these qualify? Lots of speakers can play jazz or classical or pop loud but massive guitars kill them...
These can handle massive guitars, no problem. They're not perfect, but if you want big, loud, flat, clear music, you're not going to do much better elsewhere. To go much louder and sound as good, you'll probably need to spend 3-5x the money and have a much larger system.
How about 308p and 708p? Hiss? I totally HATE hiss, could never have anything with audible hiss.
Not really. Compression drivers often exhibit bizarrely high H2, but it's clear that they aren't really misbehaving because none of the other harmonics come up (notice that H3 is basically through the floor, never mind H4 and H5). As far as not being able to find its limits, 96dB/1m is really quite loud (~102dB/1m for two speakers in room) and the speaker really isn't complaining even at that level.
I'd opine such a paper is too old. I'm not aware of any modern studies of the spectral distribution of music (or movies)...someday I'll do it and publish again...maybe when I retire ha ha. I can only say from live concert measurements that energy drops off a lot at greater than a few hundred Hertz (Hurtz?
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Page is moved or something...what is the title of the document? Great stuff, I want to read it.
Rahan
Active Member
Yes they share the same CD 2409H. The hiss is from the amp, not the CD. My set up with 708i and 705i is dead silent with the dci4/600.
Anecdotally I could buy the 350Hz, however that reference just shows a table, not any kind of data to justify the numbers within. It also says 1998 which is fairly old, though I would not think music spectrum has changed drastically in those 26 years ago.
We'd have to see pictures of the whole room and setup. Reflections could have a big effect, though yes there can certainly be speaker-to-speaker variations. Ideally you would have someone else swap some of the speakers positions without telling you which goes where, and listen if the problems go to a new position or move with the speakers. Alternatively I have a special green pen you can put certain markings on the back of the case which will fix all these ills, a mere $666, I take PayPal AliPay Zelle Western Union unmarked cash bills diamonds (please provide conflict-free certification), raw lithium...
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