setting gains in a bi-amplified system

[helotaxi 5,000+ posts]

sorry for the hijack but is this is what recommended when setting gains for the tweets? i have my system bi-amped too and i set the gains using the tutorial for both mids and tweets using a 1khz test tone. so if you are correct should i use something like 10-12khz for my tweets?

The BEST way to do it is with a combination of an o-scope and an RTA. Using a 0dB sine wave near the middle of the driver's intended freq range, set both amps just shy of clipping on the O-scope. Then with a pink noise track and the RTA, dial the louder of the mid or high amp down to match the level of the quieter of the two and adjust the crossover points to get the smoothest transition between them.

 

[alphakenny1 10+ year member]

^^ hmm so what i'm getting is this for the sub, crossed at 63hz so use a ~40hz tone? mids are BP at 63 and 2.5 so use a ~1.2khz tone and for tweets HP at 3.15khz so use a ~11.5khz tone? do you recommend using your normal listening levels when setting with an oscope (ie +3bass, +2 mid, + treble and sub level setting at max)?

also no RTA around, just an oscope //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif. I can level match on my HU though.

 

[KyleScha 10+ year member]

I have more than enough power and headroom with 100W to make my ears bleed. 150 should be more than enough unless you have hearing problems...seriously. IIRC Bostons tend to be fairly efficient anyway. You should be more than good to go.

If the Pro60's can go as loud as my SL60s without distorting I'll be happy. I actually dont know how loud my SL60's go, I never really properly set the gains until last week (but it snowed so I havent really been out) I just turned it up until I was happy with it.

I've also got a small car (toyota MR2) so that helps as well. They might be coming tomorrow, I'm excited. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[helotaxi 5,000+ posts]

do you recommend using your normal listening levels when setting with an oscope (ie +3bass, +2 mid, + treble and sub level setting at max)?

If you normally listen with those HU settings, then yes. You can use nice round freqs for the test tones, too. 50Hz sub, 1k mids and 5 or 10k tweets.

also no RTA around, just an oscope //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif. I can level match on my HU though.

The point behind the RTA is to set the levels to arrive with a flat response curve all the way across the mid/high range. Subs are just a matter of taste and can be dialed out so just set the gain with the o-scope for them. You can make adjustments with the HU but you want the RTA to use as a reference because the mid and tweet sensitivities are different and setting the gains to max unclipped will probably result in a skewed response.

 

[alphakenny1 10+ year member]

well in my HU i could play pink noise and it will show a graph of the response curve. i'm not quite sure how accurate it is though. if its sufficient, can i use this?

 

[helotaxi 5,000+ posts]

sure. That should work well enough.

 

[alphakenny1 10+ year member]

thanks helotaxi for the help man!!

 

[KyleScha 10+ year member]

I got my Pro60's in yesterday, and they were a huge improvement over my SL60s. I need to break them in, so I didnt turn them too loud. Which is a good thing since I lost a little bit of hearing seeing how loud my SL60's would go on 150w (the answer is too loud)

My only complaints are I cant quite turn the tweeters down enough (so I need to use headunit to turn down the treble, which also turns down the woofers slightly, leaving it sounding very soft. I dont mind the aluminum tweeter so far though. I think it actually makes things sound a bit more realistic since most high frequencies are metal objects to begin with, whats a better way to replicate them than with a metal speaker?

Also, a quick question about the JL amps. It automatically switches the voltage down right? Because with my SL60's I set 150w (with a 1khz test tone) to be at 30/35 on the HU. Since the Pro60's are a lower impedance, at the same voltage it would be producing higher wattage (correct?). But because of JL's regulator, no matter what impedance speakers I use it should be producing the same wattage at the same volume level no matter what speaker impedance is used? hope this makes sense.