I think this review took me about a minute to read - there's that little wrong with the speaker, and hence very little to say about it!
Mind you that positive PEQ cause ringing in time domain which can be audible especially at higher Qs and such higher frequencies which is something that the Harman score doesn't take into account:Filter 5: ON PK Fc 2295 Hz Gain +2.51 dB Q 12.00
Good point, and measured distortion (THD) of my JBL 308p at my max listening levels is below 1% across the whole frequency range, although I got a bit torn apart by posting this in another thread, so take my results as you will, I think some people find them questionable:Yeah, looking back at the JBL LSR308P MkII review, it's clear that JBL might be eating its own lunch with that model at an 85% discount versus the 708P. The 308P MkII has smoother in-room response and better directivity, and the only sacrifice appears to be a bit more distortion.
What is the target tilt for estimated room responses? 13 dB from 20 to 20 kHz?They do react very well to EQ. If you push a bit the number of PEQs, you get a score of 6.7 which is as good as Genelec 8341.
Eq is:
Code:EQ for JBL 708P computed from ASR data Preference Score 5.0 with EQ 6.7 Generated from http://github.com/pierreaubert/spinorama/generate_peqs.py v0.4 Dated: 2021-02-02-07:53:25 Preamp: -1.1 dB Filter 1: ON PK Fc 1126 Hz Gain -3.77 dB Q 0.10 Filter 2: ON LS Fc 1961 Hz Gain +2.87 dB Filter 3: ON PK Fc 905 Hz Gain -3.77 dB Q 4.41 Filter 4: ON PK Fc 14315 Hz Gain -4.04 dB Q 1.43 Filter 5: ON PK Fc 2295 Hz Gain +2.51 dB Q 12.00 Filter 6: ON LS Fc 509 Hz Gain -1.70 dB Filter 7: ON PK Fc 7169 Hz Gain -1.59 dB Q 4.17 Filter 8: ON PK Fc 10339 Hz Gain +1.01 dB Q 4.57 Filter 9: ON PK Fc 4385 Hz Gain +0.92 dB Q 11.35 Filter 10: ON PK Fc 667 Hz Gain -1.31 dB Q 12.00 Filter 11: ON PK Fc 607 Hz Gain +2.47 dB Q 12.00 Filter 12: ON PK Fc 752 Hz Gain +1.48 dB Q 12.00 Filter 13: ON PK Fc 1562 Hz Gain +1.58 dB Q 12.00 Filter 14: ON PK Fc 5357 Hz Gain -0.54 dB Q 6.56 Filter 15: ON PK Fc 2494 Hz Gain -0.62 dB Q 12.00 Filter 16: ON PK Fc 1134 Hz Gain +0.80 dB Q 12.00 Filter 17: ON PK Fc 644 Hz Gain -1.77 dB Q 12.00 Filter 18: ON PK Fc 2742 Hz Gain +1.12 dB Q 12.00 Filter 19: ON PK Fc 1937 Hz Gain +0.91 dB Q 12.00 Filter 20: ON PK Fc 1759 Hz Gain -0.93 dB Q 12.00
The PEQs are not sorted by frequency on purpose. You can cut the filter where you want, the most effective PEQ being at the beginning.
Here is how the score evolved per iteration. For example, with 7 PEQs you get a score of 6.04.
After peq 5 you start to see a lot of high Q PEQs which are smoothing the frequency (and then boosting the score) but they may not be that audible.
Code:(pid=98842) ITER LOSS SCORE ----------------------------------------------------- (pid=98842) 0 +722.43 +4.97 (pid=98842) 1 +13.52 +4.34 (pid=98842) 2 +8.23 +5.23 (pid=98842) 3 +13.93 +5.34 (pid=98842) 4 +8.69 +5.80 (pid=98842) 5 +9.03 +5.91 (pid=98842) 6 +7.84 +5.93 (pid=98842) 7 +6.56 +6.04 (pid=98842) 8 +6.65 +6.03 (pid=98842) 9 +6.27 +6.09 (pid=98842) 10 +6.07 +6.15 (pid=98842) 11 +5.32 +6.23 (pid=98842) 12 +5.34 +6.36 (pid=98842) 13 +5.04 +6.52 (pid=98842) 14 +4.94 +6.54 (pid=98842) 15 +4.98 +6.56 (pid=98842) 16 +4.88 +6.58 (pid=98842) 17 +4.48 +6.58 (pid=98842) 18 +4.05 +6.65 (pid=98842) 19 +3.92 +6.71 (pid=98842) 20 +3.70 +6.72 (pid=98842) 21 +3.70 +6.72
View attachment 110058
and then the EQ version:
View attachment 110059
JBL claim to have 2 channel amplification for these speakers with a 250W amplifier for the LF and a 250W amplifier for the HF. Clearly they understand the importance of having equal capability power delivery across the audible spectrum, unlike many other companies who economise on the HF amps. Not that a single tweeter compression driver voicecoil could absorb 1/4kW for long...
JBL claim to have 2 channel amplification for these speakers with a 250W amplifier for the LF and a 250W amplifier for the HF. Clearly they understand the importance of having equal capability power delivery across the audible spectrum, unlike many other companies who economise on the HF amps. Not that a single tweeter compression driver voicecoil could absorb 1/4kW for long...
@amirm most interesting review! The menu/selector wheel reminds me of my Canon EOS cameras. Do they have captive nuts/mounts on the bottom for standmounting BTW?
I think better max SPL (less bass distortion) is a main factor. Also, the 308P has the PIR starting to slope down at around 200Hz, whereas this 708P is around 100Hz, so bass could be heard as louder. This 708P also has wider directivity (which Amir probably prefers, but reduces it‘s score).Yet the preference rating of the 308 is so much higher to nearly clear the range where you'd expect one to prefer it rather conclusively.
I'm also interested, though I'm assuming it doesn't at this price range. Do compression drivers even have hiss issues? I have no experience with them.Thanks Amir!
Does the 705p hiss? Is it worse than 305p mk2 ?
Yeah, same - those are the prime candidates for me if I ever want to get an endgame upgrade from my 308p's. Interesting that with a quick look at sweetwater(not sure if they sell at MSRP), the JBL is by far the cheapest at $1799, followed by KH310A at $2200 and the 8350A at $2399 - but here in Europe if I take a look at local pro audio retailer I've used before it's ~$2050 for the Neumann's, followed by ~$2280 for the Genelecs and with the JBL selling for a whopping ~$2340. I guess it makes sense with Genelec and Neumann being European brands, but I didn't expect this much of a difference on the JBLs.Now with this and the Neumann KH 310 A (wich objectively did better than the JBL) reviewed, I'd really like to see how the Genelec 8350 APM does.
Do they have captive nuts/mounts on the bottom for standmounting BTW?
Because the short peaks are not impossible. And where is the crossover frequency? At 1.7kHz!! You will have full energy up to 5kHz. It seems to me many of you guys just do not understand what you speak about.Can you explain why it is important? I don't understand why a tweeter should ever need 250W.
Because the short peaks are not impossible. And where is the crossover frequency? At 1.7kHz!! You will have full energy up to 5kHz. It seems to me many of you guys just do not understand what you speak about.
There are many more Hi-Fi enthusiasts than pros buying upper class studio monitors, I guess. There is a German saying that goes: "why will a dog lick his balls? - because he can" The marketing dept. has a nice point od sales etc. Similar to having 100M pixels in a phone camera (or was it 200?). Or amps with frequency response touching the long wave radio spectrum (with funny side effects sometimes). Ken Ishiwata once in the good old days of Marantz had called this "popular technology" - spot on IMHO.Anyone got a reason as to why companies bother making drivers do anything beyond 20kHz in this sector? I get perhaps if you're using singal generators to output some odd sounds in some scientific field. But 36kHz? I don't get it.