custom crossover for 2 way
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=96384
Printed Date: May 15, 2024 at 2:18 PM
Topic: custom crossover for 2 way
Posted By: sq_impala
Subject: custom crossover for 2 way
Date Posted: August 14, 2007 at 8:47 AM
Hello, I have a pair of Mpyre 65m XBL^2 drivers. (Very similar to Adire extremis) The tweeters I have to use are Focal TN-51's. I have tried to factory MPyre crossover, and the tweeter was way too loud, and the x/o lacked atten. So I tried the Elemental Designs x/o from the 6000s, and the same problem (only sligfht attenuation -3 db). Can I put an L-pad inline with the Mpyre x/o? If not can someone show me what I need to do to build my own crossover to make them sound awesome, or should I pick up an AudioControl DQX (Already have DQT though) Also any recc's on the firing of them? On/off axis? They will be in custom fiberglass kick panels made by me.
Replies:
Posted By: DYohn
Date Posted: August 14, 2007 at 10:40 AM
The Mpyre drivers do look nice. A problem you may have using them with that tweeter, however, is Focal recommends a 24db/oct crossover @ 3KHz, which is pushing the Mpyre into the area where it gets pretty ragged sounding. Plus, the Focal tweets are 94 db sensitive and the woofers are 88.8, which means you need to pad the tweet at least 5to 6 db before they even match the woofer, and then they are titanium domes so they will always sound really bright. If those tweets sound too bright to you, I suggest changing to a fabric dome. If you want to add an L-pad to adjust tweeter sensitivity it goes in the tweeter crossover, not in line with the woofer crossover. ------------- Support the12volt.com
Posted By: sq_impala
Date Posted: August 14, 2007 at 10:58 AM
The Mpyre crossover has a tweeter out, they never receieved their 10T silk tweeter to go along with it, so I purchased the set without the tweeter. Kyle from A/V told me it was a 3.5 khz at 24 db/oct. The Mpyre's sound pretty good up high without any tweeter attached now.....so I think they should be able to handle up to 3.5 khz. Can I L pad the tweeter out of the mpyre crossover, if so whats a high quality lpad to buy? If not, who wants to make me a nice custom crossover?
Posted By: DYohn
Date Posted: August 14, 2007 at 11:23 AM
What is the impedance of the Focal tweeters you have? What is the impedance of the tweeters Mpyre designed their crossover for? ------------- Support the12volt.com
Posted By: sq_impala
Date Posted: August 14, 2007 at 10:55 PM
I can't find definate numbers on either anymore, however, when I started this project earlier in the summer I saw it, and I believe they were both approx. 4 ohms, one may have been 3.4 ohm, is that close enough?
Posted By: DYohn
Date Posted: August 15, 2007 at 8:15 AM
sq_impala wrote:
I can't find definate numbers on either anymore, however, when I started this project earlier in the summer I saw it, and I believe they were both approx. 4 ohms, one may have been 3.4 ohm, is that close enough?
Yes, that's close enough so that the crossover should be functioning at the same frequency. So now we're back to the Focal needing to be damped at least 5db and the fact that metal domes are just naturally very bright sounding - which, by the way, is one reason why I have always disliked the sound of Focal systems. So get a 4-ohm L-pad and give it a try. Connect it between the tweeter output from the crossover and the tweeter. ------------- Support the12volt.com
Posted By: sq_impala
Date Posted: August 17, 2007 at 2:09 PM
I've searched through parts xpress and a few other sites and done some searching, and have not been able to find a 4 ohm L pad. I found an 8 ohm pro audio one on ebay.....that won't do me anygood though. Any ideas where to get one?
Posted By: DYohn
Date Posted: August 17, 2007 at 2:47 PM
You can use a stereo 8-ohm L-pad and wire both pots in parallel for 4-ohms. This one would work.------------- Support the12volt.com
Posted By: sq_impala
Date Posted: August 17, 2007 at 10:29 PM
Do I need two, or just one? How should it be wired (more in depth than parallel, like soldered, where to, etc...) Is there an instruction manual? How should I fiire the speakers, on.off axis?
Posted By: DYohn
Date Posted: August 18, 2007 at 12:01 AM
You need one of the stereo L-pads for right and one for left. No, there will probably not be an instruction manual. You should aim your speakers on-axis to the primary listening location if you can. Here's how to wire the L-pads: Each pad will have three terminals. (A stereo l-pad is actually two pads connected to the same shaft.) Connect the furthest left and right terminals on both pads in one stereo set to the tweeter output of the crossover, negative to one side and positive to the other side. Continue the negative wire to the tweeter. Connect the positive wire from the tweeter to both center tap terminals on the L-pads. Now you can use the L-pad to adjust the volume going to the tweeter. If you don't understand this, you may want to get some help from an installer in your area. ------------- Support the12volt.com
Posted By: stevdart
Date Posted: August 18, 2007 at 12:22 PM
DYohn] wrote:
ach pad will have three terminals. (A stereo l-pad is actually two pads connected to the same shaft.) Connect the furthest left and right terminals on both pads in one stereo set to the tweeter output of the crossover, negative to one side and positive to the other side. Continue the negative wire to the tweeter. Connect the positive wire from the tweeter to both center tap terminals on the L-pads. Now you can use the L-pad to adjust the volume going to the tweeter.
------------- Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
Posted By: DYohn
Date Posted: August 18, 2007 at 3:02 PM
Thank you Steve! ------------- Support the12volt.com
Posted By: sq_impala
Date Posted: August 19, 2007 at 1:37 PM
Should the connections be soldered, or just clips? Would a four ohm L pad be preferable, or same results?
Posted By: DYohn
Date Posted: August 19, 2007 at 3:42 PM
sq_impala wrote:
Should the connections be soldered, or just clips? Would a four ohm L pad be preferable, or same results?
Soldered is better, and in general the same results. ------------- Support the12volt.com
Posted By: sq_impala
Date Posted: October 08, 2007 at 10:31 AM
I finally received my l-pads, they are the exact ones pictured by Stev. I understand his drawing, but can someone tell me exactly the connection points I should solder? Specifically the ngative part.
Posted By: DYohn
Date Posted: October 08, 2007 at 10:59 AM
One wire connects to the negative output from your crossover to the negative terminal on the tweeter. Another wire connects from the same negative terminal on the crossover to both "Right" terminals on the L-pad, which should be soldered into place for best results. ------------- Support the12volt.com
Posted By: stevdart
Date Posted: October 08, 2007 at 6:28 PM
You'll most likely find it easiest to use a short jumper wire to connect the dual right terminals on the Lpad. Then connect a wire from one of those two terminals to the crossover as DYohn described. After all wiring is twisted securely to all terminals, solder every connection. The drawing indicates continuous lines, but the Lpad dual terminals left, middle, and right are each parallel-connected with short wires. ------------- Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
Posted By: sq_impala
Date Posted: October 11, 2007 at 1:36 PM
Thanks for all the help. Justin finished tuning the system, and it sounds great. The L-pads work better than I could have ever expected, and were pretty easy to install after your thorough directions. The finctionality of the L-pads makes me question why more people don't use them? Are most people going active now? Thanks again Steve and Dyohn. I appreciate your help.
Posted By: DYohn
Date Posted: October 11, 2007 at 4:57 PM
Glad it worked out for ya! Commercial system don't use L-pads very often because they can be expensive. I've used them in installs that need them. Most commercial crossovers have fixed attenuators that tend to be sufficient for all but the most critical installations. ------------- Support the12volt.com
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