Custom Speaker system

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I am currently making a speaker system. I have made a center channel and now I am working on some rear speakers. This is my first time making speakers: Please bare with my ignorance. The rear speakers are composed of a MB Quart 19cm tweeter(max wattage handling is 70 watts) and a pioneer 4"(max wattage handling is 20 watts); they are each 4 ohms and are in a series. I was wondering if there was a way to change the wattage handling per speaker. I would like to get good highs from the rear and not have to worry about the pioneer adding too much bass. Plus I dont want to Max out the rear at 20 watts. I know running the speakers in a series changes the wattage handling, but I am still concerned I may get some muffled sound. I have tested the speaker in a box I made. The unit sounds great but if I go too high the pioneer maxes out and the MB Quart can't be heard. Is there a resistor or possibly a wiring scheme that would let me
change the power per speaker? My receiver has the capabilities of putting out 80 watts to the rear and I would like to be able to get as close as I can to that. If I should buy other speakers I am up for any suggestions! Thanks in advance!
 
I don't have a Xover. I have some that came with the Mb quarts, but I wasnt sure if they would help in this situation. Again, this is my first time so if I am mistaken let me know. They are in a series to take the speakers from 4ohm to 8ohm. That was the only way I knew how to get them compatible with my reciever. I thought Xovers only allowed you to change the range(Hz) of sound going into certain speakers. Do they also allow you to change the power? Please advise.
 
XOs can be as sophisticated as you want them to be.

one can consider series XOs (andy graddon's site is useful) but i dont think putting a tweeter and woofer in series is going o help much.

in fact i won be surprised if you have not already blow your tweeter using this configuation.

what you will for a basic Xo is a capacitor and an inductor. the tweeter (if still alive) might have come with such a crossover.

if however you are considering parallel connection, www.lalena.com has simple equations for parallel networks.

hope this helps.
 
Just to get you started so the speaker works to some reasonable degree of satisfaction - assuming that you haven't already burned out the tweeter, do the following:

Wire the 4" Pioneer directly to the amp with + on the speaker to + on the amp and - on the speaker to - on the amp.

Attach one end of a 5mfd non-polarized electrolytic capacitor to the + terminal of the tweeter. Attach the other end of the capacitor to the + terminal of the amp.
Connect the - terminal of the tweeter to the - terminal of the amp. The capacitor keeps the low frequencies from getting into the tweeter - this is essential.

The resistance of the speaker combination will be somewhere around 5 ohms and will probably be safe for the amp.

When or if you become dissatisfied with the sound, learn about speaker building from a good book. One of the books written by David Weems would be good for a beginner.
 
First of all thank you both for your great ideas. The MB Quarts did come with some Xovers, I will take a look at them and read about what they can do in terms of power delivery. The funny thing about this set up is well the MB Quart has a much better range (50Hz - 20kHz); the pioneer is only 70Hz-to 20kHz. The tweeter has not blown out, and I didnt think it was possible to blow it out with the setup I had(even though it is pretty simple). I will get a good book, I was hoping I could get away with a few posts. It looks like this will turn into a huge project.
 
It looks like this will turn into a huge project.

Nor necessarily a huge project, but an interesting one where you will learn a lot and - if done right - one that will be very satisfying.

Today I took a mackie HR 624 home, a powered speaker - studio monitor that is supposedly very neutral and is very well received by the pro crowd.

I wanted to cut down on my equipment somewhat, having my diy speakers all actively driven by a total of three amps and a digital x over and a digital equalizer.. If that mackie was any good, I would sell some of that stuff and would live happily ever after.

I set up everything properly, had the auto q roomcorrection done and after ten minutes i knew that my homebuild ones with vifa drivers - a total of 300 or so dollars - were outclassing that mackie by a mile. Good for my ego, but not good for my goal of minimizing my equipment. I really had wished those mackies would work for me.

Of course - the whole system is worth about five times what those mackie cost, but it is all build around those now seven year old homemade speakers who kept improving with each new amp or new and more versatile crossover.
 
Ben,

It doesn't sound like the MBQ driver is a tweeter, I think it's a full range. So is the Pioneer. The way you have it is about the best you can do under the circumstances. You have wired them in series to get your 8 ohms. Having them that way is OK but not what you would call normal. Usually when the drivers are in series, they are the same driver not different ones. But that's OK, it won't hurt anything. It doesn't sound like you need a crossover, both of those are intended to run full range.

When you get a book, it will outline the basics of speakers, boxes and XO's. It's a wonderful hobby, I wish you speedy knowledge.

Cal
 
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