I'd like to add my 10" powered, enclosed sub to my 2 channel system, intrigued by the thought of active xover for it, but they seem a bit pricy.
Was wondering if anyone knew of a decent diy active sub xover?
Gene
Hi Gene,
By active, do you mean a Behringer type digital speaker management device, or do you mean a simple analog line level filter?
For external analog line level crossover filters:
http://sound.westhost.com/project09.htm (http://sound.westhost.com/project09.htm)
http://www.marchandelec.com/xm1.html (http://www.marchandelec.com/xm1.html)
Your sub probably has low pass filter adjustments on the plate amp? Those are "active" in that they are line level filter feeding one amp for one speaker. That would be the thing to try first. What subwoofer do you have?
Something that drops in between preamp and amp like the Bryston 10b-sub xover;
http://www.6moons.com/audioreviews/bryston2/crossover.html (http://www.6moons.com/audioreviews/bryston2/crossover.html)
Background: As a result of impending divorce a few years back, began thinking of building new system, always liked the Onyx Reference 3, figured they'd be good for ht and 2 channel. Dropped the Skiing Ninja master xovers in with platinum by-pass, no rez and a few other goodies. Then ex said she'd move out, not me. So, I should have bought dedicated 2-channel speakers, but who knew at the time. Also got an AV123 10" sealed sub, and as many did, my board blew up, so have a PE plate amp on it.
Recently auditioned another members Von Schweikerts, very nice, but for rock and jazz, not tremendously better. But big symphonic work, they really were better.
So, I want to relieve the Ref 3s from handling the bottom end of the bass, and amp as well. I figure that will allow them to reproduce rest of the sound spectrum better.
But, for price of the Bryston unit, I could almost buy my own used VS speakers.
And I'm selling the house in 2 to 4 years per divorce decree, and don't want to buy new speakers till then.
Thus - how to improve what I have already, for short money. I looked at the X1 this morning already, that's certainly a contender.
Maybe something like miniDSP (http://www.minidsp.com/)
The parts express plate amp probably has the filters you need to pull this off without buying another box. It would be better if you didn't have to put anything in the Onix signal path. But to get excellent phase coherence you will need to do that, and the Marchand will work fine. But try it without first, just using the plate amp filter controls.
There are a couple issues to consider when adding sub to mains.
Phase: As mentioned above, you want the subs to be in phase (phase coherent) with the main speakers woofers through the crossover band. This is what makes that bass detail, fast bass that you are seeking with the sub. This is not possible if you leave the Onix ports open because port phase twists like crazy. So you have to seal the main ports, then set the sub to 12dB low pass slope to match the rolloff of the sealed speaker, adjust the sub freq and volume to fill in under the mains by ear or with a SPL meter if you have one, then adjust the sub phase switch or knob so the phases are matched. Adjusting phase is simple if you set the phase to zero and put the sub at same distance from your ears as the main woofers. Up on a stand sounds even better... Your PE plate amp can probably do all this. The Bryston might give you more options or finer control, but in concept the sub controls do the same thing. Whether the sub filters are good enough quality parts for precision adjustments is another question, but probably so.
The other issue is the single sub in a stereo system. Assuming you're not buying another sub, you need to either sum stereo to mono, or choose R or L signal for the sub. Summing smears the detail, so I prefer to choose R signal because most classical bass is on the right side. Most popular and jazz is in the middle. Bass might seem too quiet because you only have half of it, but you can adjust the sub volume for that. Maybe you'll like summing better, for me it loses too much detail, especially with very detailed main speakers.
If you try the plate filters first, just run a speaker cable from the main amp right channel posts to the sub's speaker level input. This will prevent any small phase error picked up by the main amp. If you don't have extra speaker cable you can split an RCA to the sub line in, no biggie, most amps are pretty flat phase anyway.
Gotta say Rich, I'm not hip to using the plate amp electronics, it feels like I'd have wasted the money I spent on the improved xovers in the Ref 3s. Obviously, I don't think much of the PE xover, though I have no concrete reason to think so.
But I guess I should try that 1st to see if it even makes any kind of improvement I'm hoping for. If not, then why continue.
Quote from: shadowlight on April 14, 2012, 04:10:19 PM
Maybe something like miniDSP (http://www.minidsp.com/)
hmmmmm, lot of reading there, but it may have a solution in there somewhere.
The Onix passive crossover is still used from 100Hz up, so your new upgrade passive crossover is still used. The subwoofer crossover is only a low pass filter and is only used for the subwoofer. There would be no high pass filter for the main speakers, they run au naturale, just like now except without the ports... The Onix ports that you seal only function at very low freq. and everything above that is unchanged. Plugging the ports makes a rolloff that acts like 2nd order high pass filter. Your regular amplifier will still power the Onixes through their crossover, no change at all on the main speakers. The sub fills in the missing SPL of the low freqs caused by plugging the ports. The benefits are clearer bass without the ports' phase shifts, and lower extension than the ports can give cleanly.
You could run the sub with even lower freq low pass with steeper 4th order slope and NOT plug the ports, but the phase difference between sub and ports would not line up very well. Worth a try to hear the difference. Ports make a 4th order slope, sealed makes a 2nd order slope. The 2 slope settings of the subwoofer are intended to compliment either type of speakers.
You are right that you would not want to run the Onix through PE subwoofer type electronics. For similar reason, I think you would not want to run the Onix through ANY external crossover box, and you don't have to. Just add the sub to supplement and improve bass quality. The plate amp only affects the sub low freqs, where sound quality is not as important as on the tweeter. You don't hear "air" or much imaging way down low. You're only concerned with level, phase, slope and the plate amp controls let you adjust those.
So you take the signal off the Onix amp to drive the sub. Then you adjust the sub controls to fill in the bass by ear. Simple! :D I can help you by PM or phone if you want.
My MiniDSP sounds terrible by the way ... don't know if I got a bad unit or what, but it sounds like throwing a wet blanket over my speakers. Most users however report no such problem.
While not exactly what you're looking for, I've been thinking of trying one of the new Behringer iNuke DSP amps. Take a look at this and read about all they can do.
http://www.behringer.com/EN/Products/NU3000DSP.aspx (http://www.behringer.com/EN/Products/NU3000DSP.aspx)
Quote from: Vapor1 on April 15, 2012, 05:57:30 PM
While not exactly what you're looking for, I've been thinking of trying one of the new Behringer iNuke DSP amps. Take a look at this and read about all they can do.
http://www.behringer.com/EN/Products/NU3000DSP.aspx (http://www.behringer.com/EN/Products/NU3000DSP.aspx)
I love the name, might work well for driving a couple of subs. 8)
Quote from: Vapor1 on April 15, 2012, 05:57:30 PM
My MiniDSP sounds terrible by the way ... don't know if I got a bad unit or what, but it sounds like throwing a wet blanket over my speakers. Most users however report no such problem.
While not exactly what you're looking for, I've been thinking of trying one of the new Behringer iNuke DSP amps. Take a look at this and read about all they can do.
http://www.behringer.com/EN/Products/NU3000DSP.aspx (http://www.behringer.com/EN/Products/NU3000DSP.aspx)
But can "it core an apple ?" That is a lot of technology there. My buddy sweras by this stuff. He keeps trying to persuade me to take the Berhinger plundge.
For Bass management and crossover for the money and sonics as well it is the piece to buy. Not the amp but the EQ /crossover.
Not saying the Amp is not desired. As an aside my buddy literally has owned in gear what we dream about. He has owned some fine sound, period. He swears by this Berhinger gear. Now using their mono preamp, two amps, and EQ for subs. Speakers are KEF.
I take his word on this as I know what he is used too.
charles
Behringer is great, if you don't mind having to replace it in a year or two. Their reliability is known to be horrid.
I may have a line on a used Bryston unit, we'll see.
Grabbed an unused Dahlquist DQ-LP1
https://sites.google.com/site/mpbarney/home/dahlquist-dq-lp1
Going to listen to it for awhile, then some mods to circuit board, and maybe replace RCA jacks, they're junk.
Have to add caps to bring it inline with my amps input impedance of 50k ohms. The LP1 is built to expect something in the range of 75-100k ohms.
Gene, here are some nice caps you can use for your xo.
http://www.partsconnexion.com/capacitor_film_silvermica.html (http://www.partsconnexion.com/capacitor_film_silvermica.html)
.027uF = 27pF etc
So you could add 15pF at Cx location to maintain ~60Hz crossover as described in the manual.
Or you could get a few caps that allow 40-100 crossover frequencies in 10Hz increments to play around with. The higher the xo, the fuller but less resolved the sound will be. Raise the sub off the ground to improve it's resolution in upper bass. Stuff your main speaker bass driver reflex ports also might improve resolution around the xo range.
You should also replace the original .027uF cap with an audiophile approved variety like these silver micas, since it is in the signal path to your main speakers and will have a profound effect on the overall sound. Since the cap is so small your choices are limited, but silver mica is good choice.
You might as well replace the power supply caps in it while you have it open, since electrolytic caps deteriorate with age. If you tell me their size and voltage I can recommend replacement parts. Panasonic and Nichicon are good quality. For power supply storage caps you can increase the value and voltage rating over the original size as long as they still fit.
There may be some other electrolytic caps in there. Depends on how crazy you want to go. Better listen to it first, and see if it sounds like you want.
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.
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.
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
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.
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.
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.
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/ (http://www.marchandelec.com/)
Bryan
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
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
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 (http://www.diyaudio.com/forums/analog-line-level/153925-reckhorn-f-1-others-suggestions.html)
Hope that helps.
Bob
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?
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 (http://www.amazon.com/Master-Handbook-Acoustics-Alton-Everest/dp/0071360972)
Quote from: rollo on July 05, 2012, 08:09:24 AM
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.
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.
(http://cathealthstore.com/sites/default/files/imagecache/product_full/Product_Images/Ore_Fat_Cat_Placemat.png)
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. :-k
Quote from: etcarroll on July 06, 2012, 04:30:59 PM
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.
I've repaired two of the Onix Rocket UFW10 subs by replacing the bad caps. I've got links to threads with pictures if you need help. If you can solder, it's very easy.
Let me know if I can help.
Bob
"I had a G2g a last winter sometime and I put a lot of bass absorbtion in the corners...."
Was that before you made your custom panels? I really liked those.
Not for nothing, listening to Porcupine Tree LOUD, and digging it. Think I may be almost there, though do need a stereo sub. Recent addition of TWL power cord a very nice tweek, and replaced a weak Tele in pre offset imaging imbalance I'd developed.
Though I'll probably hear something at CAF that will set me off.
Heard some OB speakers I loved last year, though went back in afternoon and they s*cked, go figure.
Breaking my bass out seperate is nice so far, the mids and high end 'crisper', guess cuz neither main amp nor lower speaker drivers are dealing with those big, fat low frequencies.
Thanks Bob - help is always good. I PMed with the guy on AVSForum who outlined the MWF15 repair, he said UFW10 repair was just a variation on the theme.
But I'm open to anything you have that's specific to the UFW10.
Yup - can solder, did all my speaker xover repairs. But I do suffer from 'fat finger disease'.
You're welcome.
>> HERE'S a thread << (http://www.badcaps.net/forum/showthread.php?t=6751&highlight=onix+rocket) on a forum dedicated to bad capacitors.
Yea...there's a forum for bad caps and it's called "Badcaps.net".... go figure. :lol:
Anyway, I come along halfway through page three, of this five page thread, complete with all my photographs.
The first sub took me a long time to repair. The second one I repaired in just a few minutes. The "tip-toeing" into the first unit took quite a while. Once I knew what I was doing, I barged into the second one like gangbusters.
To date, they're both working perfectly and my son tortures them on a regular basis.
Lemme know if I can help further.
Bob
Quote from: etcarroll on July 06, 2012, 06:07:23 PM
"I had a G2g a last winter sometime and I put a lot of bass absorbtion in the corners...."
Was that before you made your custom panels? I really liked those.
Thanks..
It was last fall I think. I had the panels up also, these were big ugly things in the corners.