Where & how do I place speaker sensitivity input info.

R. Davis

I am a new user of the Driverack PA, and I've yet to find out how do I input the sensitivities of the speakers?, I have a Peavey set up with SP118 for lows, SP 1X 15\"mids, w/2\" Long throw horns. I know the Low Freq. setting is 98db SPL, the Mid's are 100db SPL and the Horns are 110db SPL. How am I to input the information into theDRPA so that I may be able to match all the speaker levels and sensitivity. The manual doesn't show this at all, so if you know how I may apply this to the DRPA please reply to me at: rdavis210@bellsouth.net.

Gadget

You haven't provided anywhere near enough information to for us to be any help to you. It seems you want to tri-amp? the system? Or are you trying to Bi-amp...?

You cannot set up a speakers 'sensitivity' unless it has a power amp built in, and then the amp is usually optomized for that speaker...

For a sensitivity setting you would need to supply amp manufacturer info, and model... Seems like you may be in over your head here? If you are truely trying to tri-amp your speakers, you would need a lot of knowledge to impliment this. If you are in fact trying to bi amp using the passive crossover in the tops I think that is do-able, but you need to provide all the pertinent info on what you have and what you want to do with the system.

Gary Perrett
Twilite Zone Productions

R. Davis

Thank you for your response, I am tri-amping my system and I'm not quite sure of the significant information required from me about my system in order to gain the proper knowledge about setting speaker sensitivity for them. The speakers i'm using are not power equipped, and the Mixer is non powered as well. This system will be used for Live Performances. I do thank you for the information you've so generously provided, and now I know I don't need to worry about that situation any longer. (I Hope!)
Rick Davis

Again I thank you Mr. Perrett
rdavis210@bellsouth.net.

Gadget

I need to know what amps you will be using for the system... model and number of each amp.

You keep talking about setting the speaker sensitivity, and I'm afraid you just don't get it... speakers do NOT have sensitivity settings... they have sensitivity RATE-INGS ...speakers are capable of putting out a specific amout of sound pressure @ a given wattage (usually 1 watt of power, the output measured @ 1 meter) that is the speakers 'sensitivity'. a speaker with a sensitivity of 100 db overall (thats average) is a very efficient speaker, a speaker with a sensitivity of 90 db is NOT a very efficient speaker and will take a LOT more power to get as loud as the speaker that is 100 db efficient...

The amplifiers have a set-able sensitivity... this is most always a number you can find out by going to the manufacturer of the amp, and looking up the spec... If the amp is in the 'preset' of the driverack, it will specify the sensitivity of the given amp... and even show you the corresponding gain pot setting to achieve this without any measurment equipment. A general rule of thumb is that the amplifier should be 2X the program rating of the speaker... this is not the RMS rating. The top speakers you have, to be powered properly would need two thousand 8 hundred watts....of power...thats 2800 watts! At 8 ohms. I'm guessing you don't have that.

If you were to run tri-amped, stereo, you would need at least 3 amps to do so... the sub amp would need to be, 2400 watts per speaker @ 8 ohms in order to be properly powered... thats a WHOPPING big amp! The amp for the horns would need to be a couple hundred watts per channel..If you run fullrange, you nedd even more power...

Now this is to be \"properly\" powered... if you have less power you need to be carefull not to damage the speakers by 'clipping'the amp. What this means is the amp has run out of gas and is sputtering, and when sputtering, the amp puts out a lot of hurtfull energy, not clean energy...

Let me make this PERFECTLY CLEAR... \"clip\" lights are BAD BAD BAD!!! on your amps... they are the billboard telling you to order new speakers because these are about to go up in flames!!! This is where the gain structure, as specified in the back of the manual, is an ABSOLUTE MUST!!

So, with all this in mind, tell me about your amps, and how many of each amp, and speaker you have.
gadget

R. Davis

Thanks for your response, I am definetly tri-amping my system and I am powering it with the model 1400 QSC amp which rates 400 watts. This I use chnl. left & right for the highs (2\" horns), and for the mids i'm using the GPS Peavey 900 amp which rates 2x450 watts and for the Mids, the GPS Peavey 2600 which gives 1000 watts per side. The speakers i'm using are the Peavey SP 1X split for Mids & Highs, and the SP 118X for the lows (18\" spkrs). The SPL settings for the Low Freq. states that for the 15\" spkrs. in the SP 1X (Mids) show 100.0db SPL (2.83 V input), The High Freq. setting for the SP 1X shows 110.0db SPL (2.83 V input). The maximum sound pressure level (1 meter) shows Low Freq. 127db SPL continuous & 133db SPL peak, the High Freq. shows 129db SPL continuous and 135db SPL peak. The SP 118X shows the Sound pressure level 1 watt @ 98.0db SPL (2.83 V input). Maximum sound pressure level (1meter) shows Sub Bass 125.0db SPL continuous and 131.0db SPL peak. I hope this information will be sufficient enough. I'd like to know how to set the proper settings so that each spkr. level match. Please note I've been told so many different ways to input different settings and the manufactors tech's can began to explain yet send me proper info. on how to do it. Again I thank you and I hope you'll be able to give me some knowledge of this unit and the proper way to use it as it has been a very great unit to put into my rack.
rdavis210@bellsouth.net.

Gadget

Ok,
Here goes...
this assumes you want to run stereo...for mono start out with mono input
1. start the wizard, select strero, (this will be a 2 x 6 mode 3 band..seepage 38 ) each of the next steps are simply answering/selecting the prompts, so follow the dirrections on the screen... these changes are accomplished by the use of the 'data wheel' and 'next page' buttons
2. (graphic eq setup) select stereo GEQ
3. (main speaker) select bi-amp ,'custom'
4. (select subs) select bridged, 'custom'
5. (select amplifiers) in each case select 'custom' at this point we WILL NOT worry about amp sensitivity
at this point we won't worry about the Auto eq wizard or AfS wizard, we are not ready yet..
6. you will be prompted to store your creation/setup...follow the prompts, I suggest putting the setup on preset 9, or 10..as these are presets you will most likley never use.
7. Now you are in the program we just set up, the red 'store' light should be lit...more on this later..
8. now press the xover button , you will need to be able to move around within these modules, so familiarize yourself how to do this if you don't already know... here I want you to set up :
A. HPF, (the lowest frequency we want the speaker, subs in this case,to go to) here we will set 45 hz by selecting an 18db/octave butterworth (BW18)next the subs
B. LPF(highest frequencies the speakers..subs in this case.. will be allowed to go) here select a LR/24 @ 120hz(linkwitz Riley 24 db/octave)
C. now for the mids, set a HPF of 120hz @ L/R 24 , set a LPF of 2000hz @ L/R 24
D. now for the (1\"exit horns), Set a hpf of 2000hz @L/R 24. there is no available LPF on the \"hi\" outs of the drpa so they are pre-set to \"out\" which means the speakers will be allowed to reproduce whatever they can.
9. the amps will then hook up to the appropriate outputs on the drpa 'hi' outs to the QSC 1400, Mid outs to the GPS 900, and the left mono lo out to the GPS 2600 set to bribged mono.

I recomend here that you consider running the mids bridged also since you have so little power here... this would almost double the power to the 15\"mids ... you have plenty of power for the horns so thqats not a problem

Now its time to rough the system in. hook everything up and have a CD hooked up so you can play it... if you don't have a CD with Pink Noise , go to \"BINKSTER.COM\" AND DOWNLOAD HIS SYSTEM SETUP cd WITH INSTRUCTIONS. Next go to the back of the DRPA manual and follow the instructions and do a gain structure,this is of the utmost importance!!!

once you have done that and rehooked the speakers up, we are ready to rough in the system. We know where every part of the system clips, and have those points memorized or better yet marked. play a CD through the system ( a good full range CD such as, Steely Dan, or Toto...or whatever you know pretty well) remembering that we NEVER exceed the marks set on any amp, they can however be turned DOWN if necessary... set a rough ballance by turning down the loudest components(speakers) to match the others... this may require turning 2 of the three down.. whatever works... There are gain controls on each individual crossover if necessary...

Now your ready for the Auto EQ 9assuming you have a \"measurement\" mic. Use the method I described called \"new indoor RTA method\" here
http://www.driverack.com/drug/view_thre ... d_id=41419

If you don't have a RTA mic you will need to eq by ear... that is after all the final step anyway...

I think I covered everything, let me know how it works.. I'm sure you will have more questions, I'll be here if so..

Good luck
Gadget

R. Davis

Gadget, you Rock dude, you've put my mind at ease now. I just want to say thank you, thank you again and again. I'll go and set this up immediately.
Thanks.
Rick: rdavis210@bellsouth.net