Guide for active crossover for Prodigy?
- Thread starter 18000rpm
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Tosh
Well-known member
Tosh, just to make sure I read the diagram and the comment correctly:
- It needs a low-pass xo set to 250Hz for the rear speaker
- The front speaker needs a bandpass with a low-pass set to 250Hz and High pass set to 80Hz
So this arrangement needs 4ch of amplification + an XO that can do both types of XO, and I think the Crown XLS1002 can do this, just need two of them.
Tosh
Well-known member
I am assuming the rear woofer does not play all the way up to the 250Hz xo point of the front woofer, but I don't know at what frequency the low pass point is in stock form. But once you go active you would set it to taste.
Well, let's turn this thread into exactly that.
To start, there are existing threads that discuss the process for various Gen1 models, IIRC, even a Prodigy. So let's start by collection links to those threads or to the relevant posts within them, and paste those here for reference. The search function with the right keywords should surface them, or scan of the DIY, Tweaks & Modifications
I can go into detail about this, but not until the weekend. Having those links here by then would be a great help.
Russr
Well-known member
Here's a thread doing that, but for an older ELS (Aerius). I think there are posts about the Prodigy as well, but the basic fundamentals are there.
https://www.martinloganowners.com/threads/how-to-active-bass-section.19237/
If the Prodigy has 2 woofers, you might end up using 2 separate amplification channels, tho' I'm not sure that is necessary. Keep us posted!
https://www.martinloganowners.com/threads/how-to-active-bass-section.19237/
If the Prodigy has 2 woofers, you might end up using 2 separate amplification channels, tho' I'm not sure that is necessary. Keep us posted!
Oh this is good stuff here. I’ll throw this into the mix for what it’s worth. I went active on the bass speakers on my Odysseys which also has 8” front and 10” rear woofers. I also replaced all 4 speakers with drivers of my choice. I also don’t use the Crown amps so I’ll just make general statements. I already had my multiple subs set up on a Behringer DCX-2496 and had 3 channels left to work with so I use that as my crossover, and yes I use 2 class AB amps for 4 channels of amplification. A Behringer KM-750 and a Crown XLi 800 both 200watts/ch @ 8ohms to match my main amp 200watts/ch @ 4ohms. I started in with those crossover numbers exactly then started playing around and I’m not sure I’m done yet but I settled in at 260Hz on both 8” and 10” and a high pass on the front 8” of 51Hz.
Looking forward to following this thread for sure.
Tosh
Well-known member
Russr
Well-known member
OK, so I'm confused here. The literature for the Prodigy states that is has 2 10" woofers, each in a separate enclosure. Are they being fed the same signal from the X-Over, or as per the diagram attached in the previous post, are they "tuned" independently? The diagram shows differently sized drivers with different impedences... help?!
I’m glad I saved these pics now they may actually help someone else. Follow this as I will post a few different replies to try and keep it simple. When they say two separate enclosures there is just a panel in the cabinet that divides it into two halves a front and back half that’s what they mount the crossover board on. And yes both front and back woofers are controlled by that crossover. But here is the pic of what it will look like inside.
Ok now I’m going to speak to disconnecting the woofers only from the factory crossover because that’s what I did. In the pics you can see the low pass and high pass connections the low pass are the woofers, loosen the nuts on the low pass and take the wires off of them and the woofers are now off of the factory crossover, I taped mine up good with electrical tape so if I ever wanted to put the speakers back to the factory crossover I can. That is them circled in the second pic. You then take the woofers out and remove the factory wire connections and tape those off as well. You can then add the third pair of binding posts and run wires from the binding posts to the speaker connections. You are then ready to connect amps directly to those speakers, and control your settings with those Crown amps.
Let me know if this helps you or just makes it worse and never be afraid to ask questions. These folks here are great at helping out.
When you put that front woofer back in with the new wires on it you’ll have to drill a hole through the panel and feed the wires thru to hook up to the binding posts you silicon up the hole after feeding the wires thru to seal it like this:
Let me know if any of that helps. Believe me it is very worthwhile doing this. The improvement in sound is not small. And having the control over setting the parameters of the crossover is such a big advantage over the passive crossover.
Why do we need to install a new pair of binding posts? Why not just use the old ones at the bottom of the speaker? Cant you just directly connect the wires from the woofers to the old posts? I guess maybe the new pair of binding posts is for the 2nd woofer?
Yes that’s exactly right you are powering 4 woofers so you need 2 pairs of binding posts. You use the one factory pair and add a second pair of your own.
This gives you the independent control over the two pairs of woofers.
Duh! I didnt think about that. I was thinking just hook them both up to the same, but you need to have separate control. Makes pefect sense. I guess its not too hard of a project. I should do it someday. Id like to maybe just pay someone to do it for me, im lazy these days.
Is it worthwhile to crossover the panels too, or not so much to be gained there?
