14 replies to this topic

[313DJ]

Thanks in advance for help,need peak voltage limiter settings and recommended crossover settings for a few different full range speakers.also if u could post the formula to get these settings that would be great,the music i play mostly is r&b and hip hop song with low bass

jbl srx715 800 watts continous/1600 program/3200 peak

jbl srx725 1200 cont./2400 pro./4800 peak

jbl srx728s 1600 cont./3200 pro./6400 peak


ev zx5 600 cont./2400 peak

[dakos]

Hello again
The formula to translate watts values to volts is this one:
Peak Limiting voltage = SQ Root (Peak speaker rating * speaker impedance)
It's also recommended to further multiply that number by (SQRoot(2)/2)=0.707. That's the number to input the DSP.

As for RMS limiter, if you want 12dB (what I recommend) of headroom then you enter the speakers continuous watts rating divided by 4.
Cheers
Avi

[313DJ]

Hello again also dakos,thanks for the fast reply,is it possible that u can do an example on the jbl srx728 so i can see how u get the peak voltage limiter settings,and for the headroom for the srx728 you would give it 2000 watts on the rms average setting-1600

watts continuous divided by 4=400 + the 1600 continuous = 2000,and i was wondering can u help with the recommended crossover setting for the speakers,and should the xover for the tops match the bottoms?

[313DJ]

hello dakos i have 2 gigs this week is it possible that u could give me the peak voltage limiter settings for the (jbl srx725 1200 cont./2400 pro./4800 peak) and the (ev zx5 600 cont./2400 peak) and once again i play mostly r&b and hip hop music,these settings will be for the itech 6000

[dakos]

Don't know how I missed answering your post so thank you for reminding me

Doesn't matter for which i-Tech the settings are for, just the speakers, so for the JBL SRX725:
Peak Limiting voltage = (SQ Root (2)) X SQ Root (Peak speaker rating * speaker impedance)/2= SQ Root (4800X4) X 0.707=98V

For the EV ZX5:
Peak Limiting voltage = (SQ Root (2)) X SQ Root (Peak speaker rating * speaker impedance)/2= SQ Root (2400X8) X 0.707=100V

For the JBL SRX 728s:
Peak Limiting voltage = (SQ Root (2)) X SQ Root (Peak speaker rating * speaker impedance)/2= SQ Root (6400X4) X 0.707=113V

The itech measures the speakers resistance so you don't need to take it under consideration for the following calculations.
Continuous/RMS limiter setting for the 725:
1200W/4 (to get 12dB)= 300W

Continuous/RMS limiter setting for the EV:
600/4=150W

Continuous/RMS limiter setting for the 728:
1600/4=400W

Hope you have a great gig
Avi

[313DJ]

hey dakos thanks this helps out a lot,but the srx725's are 4 ohm cabinets will that change the peak voltage settings,and if i set the rms limiter to  1/4 of its rms power specs will i get the maximum output or is this just a way to better protect the speakers

[dakos]

You are correct, I updated the calculation to match the correct speaker impedance.

Given that you need about 12dB of headroom then that's the maximum you can get out of these speakers.

What about timing? attack and release times? have you figured them out yet?
Avi

[313DJ]

no i'm just using the factory settings for timing,and one more question should i continue to use my bbe sonic maximizer before the amp or go straight from the mixer to the amp

[dakos]

If you're used to the sound of the BBE I'm not sure you're going to like it without the unit. The problem is that the BBE, unlike some other units, puts allot of strain on the system so the headroom is most needed.

Let me know the factory timing figures you have on the DSP...
Avi

[313DJ]

hello dakos the gig this past sat. night turned out really well,much thanks to u the zx5's sounded great paired with the qrx 218s's,i have a couple of questions,wanted to know if i could get the peak voltage limiter settings for my jbl srx715 800 watts continous/1600 program/3200 peak 8ohms running them off of a itech 6000,

2nd question,thinking about running 3 of my ev qrx 218s's (1200 cont. 4800 peak) off of my itech 8000 lets say if on the rms limiter i would usually set it at 1200 watts each chanell,if i used 1 on 1 channel which is a 4ohm load,and 2 on the other channel,would i give that chanell with the 2 subs which would be a 2ohm load 2400 watts on the rms limiter?also what would be my peak voltage settings for the chanell with the 2 ohm load,thanks in advance

[dakos]

Great to hear it sounded good

Peak voltage for the 715 is 113V.

As for connecting two speakers on one channel, the peak limiter voltage stays the same while the RMS wattage doubles.
Avi

[313DJ]

thanks dakos appreciate it a lot,starting to really like these itechs

[313DJ]

hello dakos it's been a while,and now i know y u said the processing on the itechs are superior to the drpa's,but i have a question,i now have 4 ev qrx 218s dual 18 subs,is it ok to run the 4 subs on the 1 itech 8000,for a 5 hour gig,and will that work on a 20amp circuit,i'm also planning to run 4 ev zx5's on my itech 6000,subs are rated at 1200 rms,the tops are rated at 600rms per box,thanks in advance

[dakos]

Yes, there is no problem running it this way for tops or the subs, even at this configuration the itech has allot of continuous power so don't over do it.

If you have a good 20A breaker for each itech then you're all set

[313DJ]

ok cool thanks a lot