Active 3way dcx-2496 open baffle.. help wanted

[matt12v]

Hello, any of you guys out there using the Behringer dcx-2496 in open baffle designs!?... I need help! So far this forum has been a great indispensable wealth of knowledge for me I don't post on here much but I'm looking for some help with my system. I'm in the process of finishing these mains but I'm having trouble with the low end.

Right now what I am running is a Marantz Preamp into the Behringer dcx-2496 active 3way crossover into 3 amps. 1. a modded Sonic Impact T-Amp runs the 2 Seas 1212 1" Tweets 2. a Carver TMF15-CB 100x2 running 4 of the new 6.5" Ascendant Audio Mid basses at 8ohms. 3. another Carver TMF15-CB 150x2 running 2 TC-1000 10" in vented enclosures at 4ohms. I have the mid/tweeter crossover point at 1.7khz 48db/octave and the sub/woofer crossover at 184hz 48/db lol. ops: Before you yell at me here is the trouble.

I am new to open baffle designs but to me open baffle is the only way to go 8) . My last set of speakers I made lasted me 9 years and had enclosed Seas Excel Magnesium 6.5" and Scan-Speak 9300 tweets. When I first heard an open baffle design It blew my old setup away! The thing im going for this time is a warm sounding midrange. The trouble I am having is after shelv EQing the midbass almost flat I still have to crossover the Sub up at 184hz to get the best warmth in the midrange. When I do that everything is Exellent but the low end is then lacking punch. When I cross the Sub/mid over at 100hz or so then I have plenty of punch or slam but not the warm midrange.

HHrrrm I have tryed eqing every which way but there seems to be a loss in dynamics somewhere. Has anybody else experienced this? Maybe I am doing something wrong or I need a more powerfull amp for the TC-1000? Better yet maybe I need a separate sub.. maybe a 15" Sonosub :twisted: hehe. I need some bass management please. Any input or suggestions would be appreciated, thanks.
Matt

[ThomasW]

Thoughts....

Is there baffle step?

A single 10 in a dipole has pretty limited output.

Do you have any FR plots?

[matt12v]

Hi Thomas, thanks for the reply as for the baffle step and the frequency response plots. I had one of my friends help Eq the mid basses almost flat from 2k down to 100hz using the dcx-2496's built in parametric eq's and his True RTA but I dont have his measurements. I'm sorry I forgot to mention the TC-1000 10"s are actually each in a vented 1.7 cubic ft. enclosure tuned to 26Hz with a rear firing vent that is 3"w x 3"h x 18.5"long. The design is a hybrid of sorts. I have True RTA but I guess I need to break down and buy a mic and input box to see whats really going on?

[ThomasW]

Ruler flat frequency response is usually pretty boring. So I think you'd find that the inclusion of BSC would be beneficial even with the close proximity to the wall.

The bass bins look to be than larger than 1.7 cu ft?

[cjd]

Push the tweeter down a bit, say 1.4 or 1.5k. See if that helps any.

Alternatively, try 1.7 or 1.8k with a shallower slope.

My listening experience with the DCX (and the DEQX) left me thinking they were good for crossing in subs and for experimenting.

What kind of music are you using? What things are causing you to have the "lack of dynamics" feeling?

C

[Paul W]

Nice looking speakers!

Are you sure you have EQ'd for the same FR at both XO frequencies? Were all of the adjustments made with the speakers in their current position? As Thomas mentioned, they are extremely close to the wall so reflections will play a substantial role in response.

Another thing to check would be the reverse null at crossover. If you can't bring that in with slope EQ, try adjusting "short delay" on the mids...the 2496 auto adjustment for delay works quite well.

Yup, you need a microphone!

[matt12v]

Thanks for the kind words. Hehe flat response is boring to me too. I just used that to start from and go back to. I have a flat response from the sweet spot with all drivers in the place that they are in the pic saved in the EQ settings. I then can tweak to my hearts content after that :W

Yes the enclosures are 1.7 internal I swear :lol: accounting for bracing displacement and port area. What do you guys think would be optimal spacing from the wall? Right now I am stuck in a small @#! apt. but moving this weekend to a house finally :T I've been waiting 6 years to unleash the Real Jarassic Park in my living room!

Well I tried pushing the tweeter down, but my ear still prefers the 1.7khz point on axis.. I spend all my time in the sweet spot usually. I tried the short delay on the mids and that made a huge difference in SQ at about 8ms.. should I use some delay on the tweets too? My source right now is an upper model Harmon Kardon single CD player and I mostly listen to classic rock and jazz, but the music is still missing the slam I want from the 10" at lower volumes.

The thing is the crossover doesn't seem to be seeing enough input signal maybe because when I set the preamp level out at high levels and set the amps at low levels it seems to let a stronger dynamic signal through to the crossover? So then the sound is better at lower volumes (What I want). But the trouble is I am still using the same Preamp/7.1 A/V Reciever to power the center and 2 rears so the Preamp level has to be usable for HT. Man, I never realized how much work it would be to get active speakers dialed in.
Best reguards, Matt

[BobEllis]

My guess is at the lower crossover frequency your 6" drivers are running out of steam. Linkwitz's Thor uses 8" drivers to go down to 100 Hz. It there an issue running your suba at 184 Hz.?

Yes, correcting the Mid-Tweeter timing will have a positive effect.

[sfdoddsy]

Are you sure you are applying enough dipole boost to the mid range? I use the DCX 2496 and have it set up to provide similar EQ and crossovers to the Orion, albeit tweaked for my setup.

My mids are boosted by 22 db, for example.

Cheers

Steve