Is there a good diy active sub xover?

[etcarroll]

Thanks Rich - I'll probably do just that.

First though, want to slowly raise the xover point until I get to the point the mono sub/bass begins to distract from the stereo image higher up.

Then find another sub for a stereo pair.

Then begin upgrading the LP1.

The RCA jacks are crap as well, they gotta go.

[richidoo]

Switchcraft RCA panel jacks from mouser are tempting, but the barrel is .001" too small, plugs don't ground well.

Vampires $11/pair at percyaudio.com

Maybe the original jacks are just dirty? They might be plated brass which would be better to keep than to replace with Chinese zinc parts like Dayton.

[etcarroll]

No - they're junk.

Lot's of links about upgrading LP1, almost all start with 'dump the RCA jacks'.

How high would you raise a 10" sub up off the floor?

G

[richidoo]

My 10" sub has clearer details and more open sound when up on a 27" speaker stand than on the floor but I never tried any other heights.

[etcarroll]

Whoa - 27"?!?

I was thinking of getting some Herbies isolation products for my speakers, sub as well. But up on a stand.

Well, I do have stands, guess I can try it.

[richidoo]

The same sub sounds very clear when in another room down on floor up against the wall. So it's probably just room acoustics why I liked it up on a stand. But worth experimenting with the location to get the best out of it.

[bpape]

Might want to look at these guys.  Have had many customers use these, either pre-built or in kit form with great success.  Have heard a couple of them and always thought they sounded great.  Tons of options too....

http://www.marchandelec.com/

Bryan

[BobM]

I have an NHT X1 subwoofer crossover that I use with my Calipers. They also made an X2, which I think will control 2 subs. It sits between the preamp and the amp. It has a very rudimentary switch toat allows you to cut off the signal going to the amp at 50Hz, 75Hz and 100Hz.

There are RCA outs to your subwoofer with some very complex controls for variable volume, phase, etc. I can say that this has been very effective for me and it is an incredibly transparent unit, not having any deleterious effect on the transparency of the main speakers at all.

Good luck,
Bob

[rollo]

   Try placing your Subwoofer off the floor at 20% of your room height. Very affective, give it a try. Amazed me.
   However the biggest improvement was adding a third sub in the rear of the room. Thanks Scotty.
     Active Crossovers IMO are one of the hardest devices to design properly. Saying that a lesser kit design may be moot compared to say "F" Mods" passive in line filters. As the quality of sound just may be equal. IMO I would try running the sub up to the mains that are cut off at your desired frequency range and not use an active for both.
  Relieving the main speakers and Amps from producing frequencies it cannot support is the most affective thing you can do for your system. Then experimenting with the subs crossover to get synergy IMO wins hands down. Now if your sub has no built in crossover your fooked. Have fun trying.


charles 

[Bob in St. Louis]

Check out the Reckhorn. They've got a tidy little crossover unit. I can't speak for its performance, but it looks neat for what it's advertised to do.

--> CHECK HERE

Hope that helps.
Bob

[etcarroll]

Bryan, Bob & Bob -

Thanks for the pointers, but I have recently purchased a unit, a Dahlquist LP1.

Now I'm dialing it in.

Then I'll probably perform some upgrades/tweaks, Rich was pointing out some potential upgrades for me to consider.

Charles - is there some documentation/white paper to support the 20% figure?

[richidoo]

It is common belief to put speakers at the 1/5 position, or 1/3 position relative to room dimension. I don't know where it comes from but 5 and 3 are prime, and primes are often used in acoustics to create pseudo randomness which is what you want to mix up the modes that would otherwise form in simple proportional dimensions.

I think Alton Everest talks about it in his Master Handbook of Acoustics., but I can't remember for sure.
http://www.amazon.com/Master-Handbook-Acoustics-Alton-Everest/dp/0071360972

[BobM]

  Try placing your Subwoofer off the floor at 20% of your room height. Very affective, give it a try. Amazed me.
  

Or if it is a down firing sub just turn it upside down so it fires upward, and put a large enough piece of wood or butcher block on top of those upturned feet with a weight of some kind on top to hold it down. I also found that moving it out of the corner into the center of the room helped definition tremendously, contra to the common philosophy. I found that corners lead to one note booming bass, which is fine for dinosaur stomps, but not optimal for music.

That worked very well for me for the longest time.

[etcarroll]

Forward firing Onix UFW10 with the PE amp, though I ordered the needed caps to replace the cheap Chinese ones that blew on all the original amps.

I need to find another blown one on ebay and buy it for short money.

Mains are Onix Reference 3 with Skiing Ninja Master Xovers, Platinum bypass caps and fully lined with NoRez.

I heard Mike's Von Schweikert VR44jr and thought my system better on top end, tied in mids, but I really came up short down low. Bill agreed. So that's what set me off on incorporating the sub. The 3 panels behind cover the fireplace, have one in each corner for bass, and on left have panels I slide in front of RPTV screen and glass doored piers flanking TV.

The Siamese cat gets moved to attenuate bad frequencies as needed. Though at 19, she's lost half her weight and doesn't do the job she once did.

[richidoo]

I had a G2g a last winter sometime and I put a lot of bass absorbtion in the corners before the meet. It sounded about right although too ugly to leave there all the time, cotton insulation stuffed into black trash bags.   But when the room was filled up with well fed audiophiles, the bass become overbearing. I had to remove the treatments and it came back to just right.

Like cats, people make great bass traps. GIK are you listening? I know there's a product idea in there somewhere.