I would like to build my own speakers sometime this year. my plan is to build a pair of 2 way speakers and put an active crossover before the amplifiers. Obviously I’ll have to bi-amp with an active crossover. I’d also like to add 2 subwoofers to the system. What I’m unsure of is how to connect my subs. Should I get a 3 way crossover and send the low frequencies to the sub, or is there a better way? I already have one sub and I will probably buy a matching one, and they do not have high level inputs, so that won’t be an option. One more question: can I utilize the balanced outputs and the unbalanced outputs on the preamp at the same time? For instance, can I connect the preamp to the crossover with the balanced outputs and connect the preamp to the subs using the unbalanced outputs, or can you just use one or the other?
the system will be set up like this: cd transport>dac/preamp>active crossover>poweramps>speakers
Thank you so much to anyone who is able to answer this question.
-Jon
Not sure what you are going to gain here.
That is a lot of cash and money just to power a tweeter. Unless you are going to get fancy and use DSP for Eq and time alignment, I doubt you will have an advantage over a passive design.
I assume you are going to use an AV pre/pro to drive this. In which case you use the sub outs to power subs, then you also capture the LFE signal. If you use a three way active crossover, then you will need to design and build a mixing circuit to blend in the LFE. So a lot depends on the frequency you cross to the sub. If it is 100 Hz and below, then I would not use a three way crossover.
You also have to decide how you will power and protect your tweeter, if you use a two way active crossover. Tweeters take little power for one thing. If you connect a power amp directly to a tweeter, you will soon blow it. You have to protect from pops and thumps. The first turn on thump will be the end of the tweeter.
The real advantages of active bi-amping come from crossover points lower in frequency.
So If you are going to go to this expense and trouble, I would actually design a three way. Then you can select a midrange driver that can handle the whole of the speech discrimination band. So crossover points at 400 Hz, and 3.5 to 4k range. Use a passive crossover for the upper crossover and active for the lower, and then you get to pay dirt. That is what I would do.
The other problem you need to solve is how to handle the baffle step compensation from an off the shelf crossover if that is what you use rather than a custom one. This is to compensate for the transition from half space, to full space radiator. This compensation is a function of the width of the front baffle, and there needs to be a boost of 6db below the transition point. If this is not applied the speaker will sound thin. This is actually more easily done with an active design over a passive one. If you know what you are doing you can make this variable to fine tune a speaker to its position in the room to adjust for boundary effects etc.
If you have never designed a speaker before, then starting with a good two way passive design is a good way to start.
If you have never designed a speaker before, then I don't think you are ready for project where you need a bit of experience under your belt.
To your last question you can use balanced and unbalanced outputs at the same time on a pre/pro. However the only time I can see this being advantageous is if you are designing a truly potent full range speaker (20Hz to 20KHZ) and need to blend in the LFE signal. That is what I do, which is also integrated with variable BSC.