I think I made a rookie mistake when ordering the drivers for my 2 way speaker build. Its my first one and have been meticulous with the details right up to the important part. I ordered 2 midbass @ 8 ohms and the tweeters @ 4 ohms. Each speaker getting 1 driver a piece of course. I could have sworn i got both 4 ohms but a quick check says otherwise. Can this work? if it will work, will it affect sound quality. They are 2500 hz crossovers and will be powered by a 2ch 100 watt amp if that makes any difference. I'm afraid I havent done a lot of studying on the electronic side of this yet and have been mostly focused on the mechanicals so feel free to educate me.. Thanks
Edit: Was able to go in and cancel that order. It appears that I need to study up a little...or a lot more before making any purchases. Thanks for the responses
Edit: Was able to go in and cancel that order. It appears that I need to study up a little...or a lot more before making any purchases. Thanks for the responses
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You can mix them, but your crossover is of interest. Halving/doubling the driver impedance, calls for a similar change to the crossover part ratings. So if you have a pre-built board for 4 or 8, one half will be wrong. However, if you are making your own, carry on, using the values of the drivers you have. Driving impedance is a major influence in the part values needed, but doesn't restrict your options. I do however think the parts would be cheaper, had you got the driver impedances the other way around.
Yes, no big problem.
You will have to pad down the tweeter anyway, so the impedance can be kept around 8 ohm. But even if impedance will be lower in the tweeter range that's no problem for most amps.
I just went with Dayton prebuilts on this. They say the woofers are good for either 4 or 8. No mention of the tweeter.
I'm seeing in the third pic that the highpass filter is rated for 8 ohms which I assume will not work for a 4ohm driver. Good news is I ordered them yesterday (sunday) and I should be able to catch them if I call first thing this morning
Usually tweeters are more efficient than midwoofers, and these in turn further loose midband efficiency due to bafle step compensation, so you almost always have resistors in the tweeter filter to bring its level in line with the midwoofer's. As the simplest example, say you have a 4 ohm tweeter that needs to be padded down by 6 dB: stick a 4 ohm resistor in series with it and there you have it, plus now the impedance of the resistor + tweeter is 8 ohms.
In reality it's rarely that simple, but with the right combination of series and parallel resistors, you can always get the right level and impedance. Which drivers are you using, and do you have a schematic of the crossover?
I was able to catch them before they filled the order and cancel it. I've been reading and youtubing about crossovers. Theres way more to all of this than I had thought. I came from car audio where crossovers werent necessary. The amp filters the frequency. There is a lot I dont know. Some of it is going right over my head. So, build postponed for awhile. Thank you for the response
I edited my post earlier to say I had caught Parts express before they filled the order so I got it canceled. In a nutshell, I didnt do enough homework before ordering everything. I also had modeled so many different drivers that I got mixed up with what I needed . In being extra thorough, I made an obvious mistake that I caught after having made it. It's good now. I've watched and read up on crossovers for the bigger part of the day today. I am now still far from being an expert but, I'm a little more educated. Just enough to be dangerous now I suppose. Thanks for your response
I guess the point being made is that if you can show plots of response and impedance for the drivers you plan to use, they can be modelled for a simple comparison of whether the generic 4 ohm or 8 ohm filter gives you a better (or indeed a good) response, and where the actual crossover frequency will be.
Yes AllenB. If we know what these speakers are (not the cancelled parts, but what you have) we can offer suggestions. Though crossover design might be the kind a DIY the OP want's to do themselves.
The first consideration is going to be how low the tweeter can go. That ensures nothing gets broken, or sounds terrible. This might be 2.5khz. Then look how high the woofer can go. It might be happy to 5khz. The overlap between the two, the area between 2.5khz and 5khz, would be a good place to crossover between them. How fast we crossover, depends on just how fast things go wrong with these speakers, outside of that 2.5khz window.
Many manufacturers of 100 coin bookshelf speakers, won't cross over the woofer at all. They will choose one who's volume fades away nicely enough, to just let it play everything. Using a tweeter, to increase the volume, where the woofer fades out. if the fade is slow, the tweeter only need come in to aid it slowly. So a single capacitor is often found, with it's shallow effect seen of graphs, of 6db. This simplicity would certainly be a start, if there is a rush to spend just a single golden coin, to get them doing something.
In most cases, our woofer doesn't come as high as we would like, and the tweeter must be used as low as possible. That might mean a tweeter that can only play down to 2khz, actually being used down to 2.5khz, with a very sharp cutoff filter below this. To avoid any 2khz noise.
That might be as much as many of us ever want to know. The perfectionist will take that 100 coin bookshelf and do it again though. Finding peaks and troughs in the driver and crossover performance, and ironing them out with individual filters, each more complicated than the whole speaker started with. They may even select crossovers that favour different performance criteria.
The specs of the woofer and tweeter are the primary dictators.
Good luck, whichever path you choose OP 🙂
The first consideration is going to be how low the tweeter can go. That ensures nothing gets broken, or sounds terrible. This might be 2.5khz. Then look how high the woofer can go. It might be happy to 5khz. The overlap between the two, the area between 2.5khz and 5khz, would be a good place to crossover between them. How fast we crossover, depends on just how fast things go wrong with these speakers, outside of that 2.5khz window.
Many manufacturers of 100 coin bookshelf speakers, won't cross over the woofer at all. They will choose one who's volume fades away nicely enough, to just let it play everything. Using a tweeter, to increase the volume, where the woofer fades out. if the fade is slow, the tweeter only need come in to aid it slowly. So a single capacitor is often found, with it's shallow effect seen of graphs, of 6db. This simplicity would certainly be a start, if there is a rush to spend just a single golden coin, to get them doing something.
In most cases, our woofer doesn't come as high as we would like, and the tweeter must be used as low as possible. That might mean a tweeter that can only play down to 2khz, actually being used down to 2.5khz, with a very sharp cutoff filter below this. To avoid any 2khz noise.
That might be as much as many of us ever want to know. The perfectionist will take that 100 coin bookshelf and do it again though. Finding peaks and troughs in the driver and crossover performance, and ironing them out with individual filters, each more complicated than the whole speaker started with. They may even select crossovers that favour different performance criteria.
The specs of the woofer and tweeter are the primary dictators.
Good luck, whichever path you choose OP 🙂
This is what i landed on. Crossing them over at 2500 hz. The crossovers are prebuilt. It was more than I wanted to tackle on my first go around with multi-way speakers. Maybe next build. Definitely next build
Dayton Audio Pro 6.5 in. 8 Ohm Neodymium Midbass Woofer Odeum 6.5N
Dayton Audio DC28FT-8 1-1/8" Silk Dome Truncated Tweeter
These are the new drivers after canceling the original order.Someone asked to post them
The only problem I see is that the low pass filter will be different, and the woofer will have ~3dB less sensitivity than the 4 Ohm counterpart, but there's no reason why you should not use these parts in a 2-way system.