Subwoofer for Omega 3 and Super T amp --- updated

John Casler · « **Reply #20 on:** 15 Mar 2006, 03:50 am »

Quote from: masi76gc

This is a very interesting discussion about subs with Omegas. I have the Super 3Rs (similar driver as the TS-3, I believe) and have tried two different subs (1 - sealed box, 2 - bass reflex, both with servo mechanisms)and found that both were too SLOW! Yes, to my ears, the Super 3R's bass so fast that subs could not keep up, resulting in sound that is not well integrated at the bottom end. Have others noticed this? If so, how have you solved this problem?

Integration of subs to mains is a very "DEEP" subject (pun intended

)

Regarding "fast" and "slow" subs: They are supposed to be slower, since they produce the lower (and slower) frequencies.

While there certainly are subs that have "hanging" and overshoot, which might even be common in low quality subs, I think the conditions that are perceived as "slow subs" are as follows:

1) Overlapping of Frequencies

2) Subs that are not "in phase" with the main speaker

3) Assorted room nodes and modes

1) Overlapping of Frequencies - If your mains play down to 38hz and you roll your sub in at 40Hz (just so you don't lose any frequencies) then you are reproducing "and overlapping", an exceptionally "large" frequency range, depending on your "roll off and on slopes".

While this may also happen in your mains (if they are multi-drivers) the speaker designer worked "dillegently" to make that "transitional frequency range" as unobtrusive as possible.

YOU!!! are responsible to do the same thing to integrate your sub.

This overlapping area if not matched and phased "precisely", will sound muddy, boomy, wooly, slow, and drone on with flannel muffled bass, as well as muddying up the upper bass and even lower mids.

Just play your "sub only" sometime to hear just what upper frequencies you are hearing. Of course the higher frequencies are not very loud, "but you CAN hear them", and this is heard as "distortion" and noise, if it is out of phase and delayed or advanced. Now of course your mains are "much" louder, but again this is sound that has to be either removed, or fixed.

So the secret is to roll your sub in "well below" your mains, and simply adjust it "upwards" until you hear the drone, or boom, or wool, then back it down, until it is clear and clean.

2) Subs that are not "in phase" with the main speaker - Now in doing the above, you may notice an improvement, but it wont be complete, until the woofers are all playing together (in phase), or maybe a better term might be in "proper phase".

The best and easiest method to acheive this is to place the subs in the exact same plane (aligning acoustic centers) as the mains. This means that the sounds arriving from your sub are not advanced or delayed, when they reach your ears. This generally means the speakers are arranged in a "semi-circle" to your listening area.

Now there are other ways to do this, through delay/advance, Speaker or room correction or phase adjustment.

3) Assorted room nodes and modes

This will sometimes make one think that the sub cannot be integrated well, but some rooms will set up bass "echo" or "flutter" where the bass energy doesn't dissipate well, and you end up in "bass soup".

So let me assure you that if you have a "good quality" sub(s) with a lot of work, and carefull tuning, you can have bass of incredible depth, dynamics, detail, and without a doubt a 3-D depth that will offer you a "spatial" feeling and perception that can be produced by nothing else.

So don't be too quick to turn that sub off or move to another, unless you have explored these concepts. You might have a great sub and not even know it

konut · « **Reply #21 on:** 15 Mar 2006, 04:46 am »

Great post John. I agree with everything you wrote except for the point at which the sub is "rolled in". If you allow your mains to run full range you'll be getting all the harmonic, phase, and group delay distortion associated with the tuning frequency of the enclosure and the resonant frequency of the woofer. You're also at the mercy of the uneven fall off of the woofer, depending on the box alignment. If you crossover at one octave above the -3db fall off, with a symmetric 24 db per octave slope, you'll get a very well controlled transition between the sub and the mains, avoid the bottom octave irregularitiess of the mains woofer, and gain headroom on the mains. The problem is, I know of no sub that includes such a crossover in its electronics package necessitating the use of an external electronic crossover.

konut · « **Reply #22 on:** 15 Mar 2006, 01:35 pm »

The sub I'm using is the AV123 Rocket UFW-12 that I posted my impressions of here http://www.audiocircle.com/index.php?topic=23039 Just recently a thorough review was posted of this sub at Secrets http://www.hometheaterhifi.com/volume_13_1/onix-ufw-12-subwoofer-3-2006-part-1.html I'm replacing the Behringer electronic crossover with Marchand XM46 passive modules at 70hz. Haven't got them yet though.

Songforyou · « **Reply #23 on:** 15 Mar 2006, 03:07 pm »

Hi Sarchi,

I have the Omega Super 3Rs and I'm using a pair of TBI Magellan VI subs (with their separate TBI200 amp/crossover). TBI use a small (6") aluminium driver that is designed for speed. They blend with the Omegas perfectly.

Way back in May 2003, 6moons reviewed the (then VBT) Magellan VIII and gave it a Blue Moon award for "pitch definition, pace and rhythm" (they have a category for everything). The subs were mated with Duo horns. 6moons have also reviewed the smaller version with an internal amp (April 2005) and gave the sub a strong recommendation. You can check out the reviews if you like:

http://www.6moons.com/audioreviews/vbt/magellan8.html
http://www.6moons.com/audioreviews/tbi2/diamond.html

The subs are unconventional: the driver is completely sealed with only a small port at the back of the enclosure. The enclosure itself is less than 15" square and only 5" high. It is raised about 2" off the floor by 4 brass spikes that screw into the bottom of the enclosure.

The small size makes them very easy to place. I have mine right behind the Super 3s (which are sitting on Skylan stands). I have found that placing them as close to the Omegas as possible works best. TBI recommends placing them between and in line with the mains, but I have swinging doors on a wall unit that prevent this.

The strength of this sub is its ability to disappear COMPLETELY. It is fast and unobtrusive. It provides a solid foundation that the Super 3s need. There is all kinds of contradictory hook-up info on subs, but I am running the Omegas full range, using speaker level ins to the sub amp and dialing in the subs' crossover somewhere around 60Hz. This adds some fill in the Omega's lower range, but in my opinion it is needed (the Super 3s are fast, but a little lean on their own).

I'm using a Mapleshade modified Scott 222 integrated to drive the Omegas. I am so happy with this combination that the only upgrade I am considering is swapping out the Super 3s for the 3XRSs and moving the 3s to my den to use with my little Sonic Impact. I no longer think in terms of changing my system; instead, I think of multiplying the same system in different rooms in the house!

Here is the TBI site. Louis has used their subs with his speakers and was the first to point me in their direction. He may have other recommendations as well. Hope this helps!

http://www.tbisound.com/

dgu · « **Reply #24 on:** 16 Mar 2006, 05:08 pm »

Like Sarchi, I have Super 3s paired with a Super T. And like him, I love the Super 3s, but want to supplement with a sub. My question is this--can you run a sub and the Super 3s off an amp like the Super T that has pretty low output and just one line out? I may someday upgrade to a Clari-T that has outputs for both, but if I could get a sub on the Super T in the meantime, I would get the sub first. Thanks!

Sarchi · « **Reply #25 on:** 16 Mar 2006, 05:21 pm »

Quote from: dgu

Like Sarchi, I have Super 3s paired with a Super T. And like him, I love the Super 3s, but want to supplement with a sub. My question is this--can you run a sub and the Super 3s off an amp like the Super T that has pretty low output and just one line out? I may someday upgrade to a Clari-T that has outputs for both, but if I could get a sub on the Super T in the meantime, I would get the sub first. Thanks!

dgu- in my tv system I had that problem, my Sony receiver has no sub output, and even though it has two sets of speaker taps, the amp can't handle the load it 'sees' with a sub and a pair of monitors. A small A-B speaker selector box ($20 at Radio Shack) solved it, basically the box gives the amp a friendlier impedance load. I'll give it a try with the Super T and confirm if it works...I'm pretty sure it will.

kbuzz3 · « **Reply #26 on:** 16 Mar 2006, 05:28 pm »

ive been fooling around with a tbi sub with my super three narrow baffles. Im very impressed thus far- way more musical then my prior sub. Highly reccomended

The only issue thus far is the itch to fiddle with the settings.....

Sarchi · « **Reply #27 on:** 16 Mar 2006, 06:36 pm »

Quote from: Sarchi

dgu- in my tv system I had that problem, my Sony receiver has no sub output, and even though it has two sets of speaker taps, the amp can't handle the load it 'sees' with a sub and a pair of monitors. A small A-B speaker selector box ($20 at Radio Shack) solved it, basically the box gives the amp a friendlier impedance load. I'll give it a try with the Super T and confirm if it works...I'm pretty sure it will.

I guess the other (probably better) alternative...once you've come to terms w/degrading your signal a bit by going through 'a box'..... is to get a sub that has high pass inputs and outputs, and feed the Omegas from the sub's outputs. So then you've overcome the load problem, + *presumably* the sub's built in crossover network will make your sub/mains integration easier as well -- the problem of overlap described by John in his eloquent post. I think the MRS-10 has both ins and outs.

Jampot · « **Reply #28 on:** 16 Mar 2006, 06:45 pm »

Careful with the super Tspeaker connections and subs- see this thread:-

http://www.audiocircle.com/index.php?topic=19141

Jim

Sarchi · « **Reply #29 on:** 16 Mar 2006, 06:53 pm »

argh

tvyankee · « **Reply #30 on:** 16 Mar 2006, 07:03 pm »

i have the omega xrs and i use them with this sub.

alot of people don't talk about this sub but i have to tell you that its fast and goes real deep and is very musical.and its not that much money.

http://www.vonschweikert.com/vrs1.html

tyee · « **Reply #31 on:** 16 Mar 2006, 07:04 pm »

I was planning on trying the TBI but Louis didn't recommend it. Read the second post on this page - http://www.audiocircle.com/index.php?topic=24054&start=10

I don't know why, if a couple of you guys like it??

mcgsxr · « **Reply #32 on:** 16 Mar 2006, 07:13 pm »

tvyankee - looks like a nice sub, and good for music - small, powerful, sealed, and simple.

Oh, and a car woofer too! That is exactly why I build DIY subs with car woofers - with the advent of affordable sub amp power, the lower sensitivity of car woofers, is easily absorbed in the design.

Now, if only I could veneer!

Songforyou · « **Reply #33 on:** 16 Mar 2006, 10:05 pm »

Quote

I was planning on trying the TBI but Louis didn't recommend it. Read the second post on this page - http://www.audiocircle.com/index.php?topic=24054&start=10

I don't know why, if a couple of you guys like it??

I saw this, was curious and actually corresponded privately with Louis about it. Fine fellow that he is, he responded and satisfied my curiousity. I don't want to speak for him, so I'll let him chime in if he desires. That is why I suggested in my original note that he might have additional recommendations. All I will say is that I am extremely happy with my Super 3s and my TBI subs and they work very well together.

But Jampot makes an excellent point regarding T-amps and speaker level ins on subs. I'm not sure how the TBI is wired. I'm curious about this because I have the little sonic impact and have ordered the Super-T too.

Louis O · « **Reply #34 on:** 17 Mar 2006, 02:57 am »

Hi,

This is a great thread about subs and some great ideas and choices. I do need some help for the recommended subs page. At one time the Creative sound sub was occupying the page and since then it has been discontinued. This was great sub for the money and design by Adire and used an Adire driver and Hypex amp. For now all feedback is welcome.

The TBI situation stemmed from a sub I had and it had issues with the port, which is resolved now. So all is good with the TBI.

Of the subs I have heard which use long throw drivers, I like sealed box alignments and steep low pass slopes. Another way to go is to use large pro sound drivers in huge boxes, but often times they wont go below 30Hz.

I did hear Adire is coming out with some new stuff very soon.

Thanks again,
Louis

dgu · « **Reply #35 on:** 17 Mar 2006, 01:51 pm »

Sarchi wrote:

Quote

dgu- in my tv system I had that problem, my Sony receiver has no sub output, and even though it has two sets of speaker taps, the amp can't handle the load it 'sees' with a sub and a pair of monitors. A small A-B speaker selector box ($20 at Radio Shack) solved it, basically the box gives the amp a friendlier impedance load. I'll give it a try with the Super T and confirm if it works...I'm pretty sure it will.

I guess the other (probably better) alternative...once you've come to terms w/degrading your signal a bit by going through 'a box'..... is to get a sub that has high pass inputs and outputs, and feed the Omegas from the sub's outputs. So then you've overcome the load problem, + *presumably* the sub's built in crossover network will make your sub/mains integration easier as well -- the problem of overlap described by John in his eloquent post. I think the MRS-10 has both ins and outs

So i think i understand all that, but then there's Vinnie's comment from the other threat:

Quote

This is just a reminder that you should not connect the speaker outputs of the Clari-T-Amp or Teac AL700P (modded or stock versions) to the speaker-level inputs of a subwoofer (or any other equipment) that ties the L and R negative speaker inputs together...usually to GND.

I'm a complete novice, so please bear with me. My question is this: does Vinnie's comment mean you can't use the Super-T with a sub as Sarchi was proposing, or does it mean that it depends on the sub? Or am I missing the point altogether. Thanks![/quote]

mcgsxr · « **Reply #36 on:** 17 Mar 2006, 01:57 pm »

It depends on the sub - ping Vinnie directly, he can assist you, as he knows the math, and can likely translate it into English for you...

Most plate sub amps and tripath amps do NOT mix, with high level inputs, due to how they are tied at negative or something... but there are exceptions, so I would ask Vinnie, as he has played with many tripath boards.

Jampot · « **Reply #37 on:** 17 Mar 2006, 03:29 pm »

Vinnie will hopefully chime in as Mark says (if he has time) but he makes it clear in the last 3 posts of the other thread. If the L/R ground is tied it will screw up a tripath chip - if they are sufficiently seperate it shouldn't.

The Sonic Impacts use tripath boards (AFAIK) which are practically identical (before Vinnie works his magic) to those he uses for the Clari-T, and therefore the recomendation applies.

Wouldn't like anyone to fry their 'chips' this weekend other than in the kitchen!

Jim

bsuhy · « **Reply #38 on:** 17 Mar 2006, 04:43 pm »

I believe the Creative Sound sub is identical to the Acoustic Visions MRS10.

Sarchi · « **Reply #39 on:** 17 Mar 2006, 08:51 pm »

I've emailed Kyle @ Acoustic Visions and waiting to hear back.