1st order ? L-R 2nd order? or transient perfect??

[Ken L]

I'm just about to order parts for adding

a beyma CP385nd and DDS waveguide Eng 90-1 to my azurahorns - with Fostex FE208EZ Sigma's in the Azura's.

Charts for these are at
http://www.usspeaker.com/beyma CP385ND-1.htm
http://www.madisound.com/fe208ez.pdf

there's not quite as much overlap for the horns as I would like, but the Beymas are recommended to cross at 1200 or higher, and the FE208EZ's are pretty flat up to 5K -

The Azuras move out of horn loading approximately 1250 to 1500 hz and the 8" drivers begin to beam around 1250. The DDS Eng 90-1 goes down to 900/1000 but is only strong down to 1100 hz.

I'm guessing that the Azura's are close to 90 degree dispersion and the DDS waveguides are 90 degree. One of my priorities is to match the dispersion patterns as best I can.

I am very tempted just to go with a 1st order crossover and caps in series - _not_ from any technical basis but from the knowledge that 1st order has some what of a "cult" following - Indeed, the first notice I took of this was a good while back when diyaudio's Nelson Pass stated words to the effect that only 1st order sounded right to him. My game plan for 1st order would be to order a bunch of caps and do it by ear starting pretty high and going down by trial and error.

However, I went to Rane's site and read their excellent crossover whitepaper - just on the face of it, it looks like a L-R 2nd order looks very good for my circumstances.

I have been enjoying reading Phase Accurate's posts and other posters giving info about Transient Perfect series crossovers - but frankly at this point in my life, I'm simply not able to follow it - but could get someone to help me if I thought that was what would be best for my situation.

Any and all thoughts and comments as to which approach you think would be best and why, would be greatly appreciated.

So what do you think?

Should I go 1st order? L-R?, or Transient Perfect?

Regards

Ken L

 

[slowmotion]

Hi Ken,

I may be wrong, but doesn't the DDS waveguide have a conical shape?
If so , will it have the same type of sound as the LeCleach' shape of the Azuras?

cheers

 

[Ken L]

Hi Ken,

doesn't the DDS waveguide have a conical shape?
If so , will it have the same type of sound as the ....Azuras?

I think I should be OK. The short depth and wide dispersion of the DDS are the reason I selected it.

They are both round, short throw horns. The dispersion angles are closer to each other than anything else I can find. I think LeCleac'h flare and Waveguide are closer to each other than anything else of similar flare and dimensions, at least that I can find.

While the flares are not identical, I also am mixing cone type drivers with compression drivers -

There are several things about this match-up that are not quite as _perfect_ as I would like.

On the other hand, things are so close to each other that it may well be killer.

So I'll give it a shot _big grin_.

If you look at the fact that most compression driver setups cross over to a 15" woofer from a 90 x 40 horn at around 500 to 800 hz with the crossover right in the middle of the vocal range, I believe that by matching overlapping dispersion angles and keeping the crossover effects out of the 300 to 3K range, I have a pretty good chance of having the best of both worlds.

At least that's the plan _ even bigger grin_

regards

Ken L

 

[slowmotion]

Hi Ken

Please tell us how it turns out, will you?
Should be interesting.

If you look at the fact that most compression driver setups cross over to a 15" woofer from a 90 x 40 horn at around 500 to 800 hz with the crossover right in the middle of the vocal range, I believe that by matching overlapping dispersion angles and keeping the crossover effects out of the 300 to 3K range, I have a pretty good chance of having the best of both worlds.

Yes, you've a point there.
I have tried to mate a comp. driver to a woofer for a simple 2-way ,
but must admit I have more or less given up . Others have made it work ok, tho

I get much better results with a 3 or 4 way setup,
so I'm fooling around with my Unity clones trying to make them work ok

Re your crossover, why don't you try to borrow another amp for tweeter duty and cross it over with your Behringer ?

cheers

 

[Ken L]

Hi Ken
Please tell us how it turns out, will you?

Yep. will do - I've got too many things I still need to do that with. I really do need to get some stuff finished

your crossover, why don't you try to borrow another amp for tweeter duty and cross it over with your Behringer ?

Planning to do that also - actually, I've got three Crown Com-tech 410's that are destined for HT. Using two of them for the subs at the moment, got two just sitting there.

While there will be some difference between the amps if I leave the tube amps in the middle, I figure I can get close enough with the Behringer to tweak it - I almost mentioned this in the initial post but took it back out before posting because I didn't want to clutter up the post and make it confusing.

I was really hoping that someone would reply in terms of Transient Perfect to some extent - because it is an option I can't do with the Behringer - and wondered what input I might get, I don't really understand what is going on there.

I've got the DDS horns on the way, and I've _got_ to get the preamp in the system, and from various posts that others have made - I'm thinking that possibly the next step after the preamp is to upgrade the insides of the Behringer -

All that before I'll really be able to tell what's going on with anything -

I don't mind telling you that I am more than a little overwhelmed with what I have _not_ gotten done that I need to get done_ big grin_


The list is longer and longer, not shorter - I used to be a person that got a lot of stuff done but that is not the case recently

regards

Ken L

 

[GM]

Considering the size of the horns and the XO point, 1st order allows way too much comb filtering in a BW where you should be able to hear it. 2nd, or preferably 4th, L-R is your best option in this app. IMO.

GM

 

[Ken L]

Considering the size of the horns and the XO point, 1st order allows way too much comb filtering in a BW where you should be able to hear it. 2nd, or preferably 4th, L-R is your best option in this app. IMO.

GM

I trust your judgement and expertise GM.


I shall pursue higher orders -

Thanks for the input.

Regards

Ken L.