Series BSC?

[PeteMcK]

will this work?

[lineup]

most probably not

you will hear sounds
but will hardly be a corossover that works, whatever vlaues you use

there are readings and schematics of series crossovers in the web
however, they are only a fraction as usual as parallel x-overs

try this google search:
series 3-way crossover OR "x-over"
http://www.google.com/search?q=serie...R+%22x-over%22

[pjpoes]

I don't want to say unquestionably no, but I couldn't make it work in my model. I've never used a series crossover in a 3-way system quite like that. I think the more common approach is a series parallel arrangement in which the upper midbass and tweeter are connected and crossed over in series, while the lower woofer is connected in parallel to the terminals and then uses a simple 1st order crossover. There is a way to add BSC in a series crossover, but the way you have shown isn't how I would do it. The problem I had with your idea is that when I adjusted the value of the lower woofers capacitor so that it was where I needed it crossover wise, it impacted the crossover point for both woofers, and created problems I couldn't get rid of.

The arrangement I would use, personally, would be to wire the woofers in parallel, and treat them as a single woofer as far as the crossover is concerned. Then use an inductor in the lower leg of the crossover. Adjusting its value just as you would a parallel crossover with an over-sized first inductor position. The problem with this method is that you would have to use an MTM or a fairly low crossover point for good summing. My personal preference would be to the series parallel arrangement.

[PeteMcK]

Guys, I'm aware of the standard way to wire series xovers.

Pjpoes, re: "when I adjusted the value of the lower woofers capacitor so that it was where I needed it crossover wise, it impacted the crossover point for both woofers, and created problems I couldn't get rid of" - can you expand on that a little, what were the problems, and how did the woofer cap affect the mid-bass xover point????

Lineup, Re: "most probably not" &"will hardly be a corossover that works" - that's a car audio answer, what are your reasons for thinking so?

[Andy G]

Pete,
I don't have time to analyse that x-o, but if you are using a 3-way series, the lower x-o point should be aimed somewhere near the BSC frequency, thus negating the need for anything like what you are suggesting. With the right driver choices you should only have to balance the mid and tweeter levels anyway !! If you need to apply BSC, you have not made the right driver choice.

The 3-way linked series is a true 3-way, and I don't think it should be used as a 2.5 as your design seems to indicate (and pipeo's results seem to back up).

[PeteMcK]

Andy, It was just a half-a$$ed idea I had when thinking about avoiding too many inductors in 2.5 way, I'm just interested in getting (reasoned) reactions...

[rabbitz]

I can't see how you can reduce the inductor count in a series xo. I've done a few 2.5 ways but the 0.5 woofer is always done as a parallel network and not within the series 2 way filter.

Andy's spot on with the woofer SPL and xo point being critical to the success of a series 3-way and provides the BSC when implemented correctly.

I find it easier to do BSC in an AR series than a standard series but the inductor count is still high. There may be some info in these links.

http://www.acoustic-reality.com/ar-sxo2.htm

http://www.acoustic-reality.com/ser-...n-3-way-xo.jpg

Tony Gee has a lot of 3-way looking speakers but the network is a series 2-way with a parallel 0.5 woofer xo.

http://www.humblehomemadehifi.com/

[Andy G]

Hi Peter,

That AR 3-way is not a true series cross-over. The top x-o point is series, but the lower x-o point is actually a parallel.

[rabbitz]

Yep... know that Andy and it's sort of what I tried on a 2.5 way once but preferred the 0.5 being a separate network away from the series. They tended to bang heads and I don't think the parallel and series like to co-exist inside the same network. I read something long ago about shared ground wires being an issue but it may be :bs:.

I did try that AR 3-way network on my mains at one stage and it was a bit bleh.

[Andy G]

As you know, I find the standard 3-way linked series VERY nice to work with .. IF you use the right drivers.

Blackwood, Rockettes, Deloreans, The Juke.. even Sauron, are all 3-way linked, all pretty well balanced speakers, and none of them use anything except the simple 3-way linked layout with padding on the mid and tweet.
(iirc, one of them has a zobel somewhere).
IMO, a 3-way should not require such things as special BSC bits and pieces.