Bi-amping 2 1/2 way speakers

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I am thinking of Bi-amping my Leema acoustics Xone 2 1/2 way speakers and have been researching how to go about this using Rod Elliot's "Benefits of Bi-Amping (Not Quite Magic, But Close)" as a kick off point.

The more I look into this the more complex things seem to become, but before going too much further I would like to know whither just simply disconnecting the initial passive crossover would work for this type of speaker and what if any pitfalls I may experience along the way.

From what I have learned so far is if the HF filter goes to the tweeter and the LF goes to the mid woofer/woofer things would be more straight forward than the HF filter feeding the tweeter/mid woofer and the LF only the "1/2 way" woofer.

please excuse my limited knowledge. I have the four amps and am prepared get someone in to disconnect the speaker crossover and to invest in an electronic phase coherant crossover and learn how to set the speakers up using it but before going any further even a simple "Yeah, no great mountains to cross" or "Nah, things are going to become a bit too techy for you my son" would suffice.

It's this "2 1/2 way" thing I can't seem to get clear info on to do with Bi-amping.
 
A 2.5 way pair of speakers will need 6 channels of amplification to copy the current crossover in line-level form.

We'll take 200Hz and 2kHz crossovers for simplicity...

The tweeter will see frequencies of 2kHz and up, so definitely needs its own amp. That bit's easy.
The mid-bass will see 2kHz and down, so will need an amplifier. Again, easy.
The woofer will see 200Hz and down.
You can either filter 200Hz at line-level and feed that signal into another amplifier (optimum) or keep the big inductor for that woofer, and put it in parallel with the previous amplifier (cheaper to implement).

If the mid-bass and woofer drivers are identical, you could try an MTM (or TMM) format, where both would see 2kHz and down. That'd get more complicated (you'd likely need BSC and vertical off-axis would get fun), but you could use your current set of amplifiers.

HTH
Chris
 
Thanks for that reply Chris, I liked the "that bit's easy" parts!

That has made things alot clearer. I think I will go down the route of leaving the big inductor in and going in parallel with the mid/bass amp. The problem of sorting out the vertical off-axis was the one i wanted to avoid.
I know it's not the optimum way of doing things but imagine that the end result will be more than worth while; opening the sound right out without going back to school :eek:!
 
Thanks for that reply Chris, I liked the "that bit's easy" parts!

That has made things alot clearer. I think I will go down the route of leaving the big inductor in and going in parallel with the mid/bass amp. The problem of sorting out the vertical off-axis was the one i wanted to avoid.
I know it's not the optimum way of doing things but imagine that the end result will be more than worth while; opening the sound right out without going back to school :eek:!

You're welcome.

IMO, if you've got enough line-level filtering to do the 2.5 way properly, and all you need is another amplifier, you could do a lot worse than one of the £5 tripath boards off eBay. I'm still surprised at the sound they make - add an old wall-wart or even a battery and give it a try.

Worst case is you've got a spare 15w/ch amplifier lying around, and you're a fiver down.

As I said - if you've got the rest of the kit to do it all properly, putting £5 here to do the tri-amping properly, its worth doing to get rid of the big inductor.
Have a read-up on sound.westhost.com/articles for more - I can't provide a proper link as the site appears to be down at the moment. Hopefully it'll come back up as its a fantastic resource for general HiFi knowledge

Chris
 
Hello again Chris. Thanks for your continued interest in my project, yeah I want to get the best out the speakers as possible and after posting my previous reply was sort of resigned to a second best approach; the best being seemingly beyond my capabilities. Thanks though to your continued enthusiasim and confident talk I think i will now go the whole hog.

I remember reading an article about my speakers which talked about some sort of "dip" at a lowish frequency and lo and behold they do lack a certain richness are a bit tight in the lower mid range, which with my new found knowledge I think probably equates to that big Inductor in the crossover. I don't really want to change speakers to ones that are easier bi/tri-amped as they are the right size for my room,they already sound great and I love the look of them. The vertical off-axis bridge can be crossed whenever......

I am not quite sure what you mean by enough line-level filtering, and are you saying that I could run the tweeters on the £5 amp (Moderator please have mercy on me).

I am not sure how much you want to get involved in this but i could post the specifications of the kit I have at the moment and when I'm home could post a photo of the speaker's crossover if that would help with any advice you can offer me.

At the moment I am at work on a ship in the North Sea and won't be home for three weeks. The internet on here runs at snail speed and sometimes is lost completly if we are in the shadow of an oil platform. I did write last night but lost the message during posting.

Cheers Hugh
 
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I have the four amps and am prepared get someone in to disconnect the speaker crossover and to invest in an electronic phase coherant crossover and learn how to set the speakers up using it but before going any further even a simple "Yeah, no great mountains to cross" or "Nah, things are going to become a bit too techy for you my son" would suffice.
I'd go with option B, just at the moment. A phase coherent electronic crossover will get you nowhere, unless you're talking about a phase coherent crossover and driver to driver combination...and even that's the tip of the iceberg (the person you get in had better know his speakers ;), and rates with a weekly discount)

You can still get usable results leaving the current passive crossover in place (if it's any good), and running each leg (two or all three if you choose) from separate amps. Maybe this will allow some wider scope for your future experiments but I'd have to add, there are many other factors of more importance than bi-amping.
 
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