Dual subs for two channel.

[Jesse111]

It has taken some real effort but I’ve concluded that two Sunfire subs can be integrated into a high end system better than one. My vinyl buddy on the other hand has concluded that it is not possible. So, here we have two opinions and both are valid and true.

The Sunfire sub offers plenty of slam for my hard rock collection. I feel it would be awesome for HT. But for most classical and slow jazz the sub might be best left out of the system. No matter how much tweaking I did I was unable to eliminate 100% of the overhang of the sub while maintaining the strong bottom end I need.

But this is where my buddy and I part ways. You see, my brother plays bass and my brother-in-law plays drums. Both have been in numerous bands so I’ve sat in on many practice sessions and concerts of theirs as well as the professional live shows in my life. To me there is a certain realism with a slight amount of bass over hang, especially when it comes to rock music. That reality is rather convenient because to get the slam I want I have to accept the small amount of bloatiness that comes with it. In order to remove every last trace of the bloat, the slam capability also is extinguished. But I would prefer no bloat at all with the slam as the final desitnation if possible.

But to enjoy the more "audiophile" perspective and pure recorded accuracy of the disc, at the expense of the lifelike performance (in my opinion) of the bottom end, it is clear to us that the Sunfires must be turned off.

One of my main references was the second note of the stand up bass instrument in the song Fever from the Chesky Audiophile Vocal Recordings. The image of that bass instrument is clearly defined through the entire song just behind my right speaker with no sub. Upon the introduction of the subs, if the crossovers were set too high or volume too loud the image would deteriorate during this second note. With the crossovers set at their lowest points (30 Hz) I was able to reduce the volumes until the image maintained itself during this crucial second note frequency. While the image was brought sharply back in to focus there was still just a slight bit of bass overhang that I can live with in order to enjoy the live performance sound I’m looking for.

Just for kicks I also tried the high pass filter system. The Sunfire high pass is factory set at 70Hz. There was a certain perceived change in the resolution that I suppose may have something to do with the B&W 800D’s not having to carry the burden of anything below 70 Hz but also certain “thinness” became immediately apparent. I didn’t spend too much time on this because my goal here is the bass issue. Then of course the entire bass image broke down because the Sunfire is totally incapable of handling 70Hz and below for music. While I enjoyed the 501’s sharing the load with the sub, the high pass route was not an option.

I lean a bit more towards the performance experience while my vinyl buddy leans more to the sound quality. However, I like to think of myself as trying to find the perfect balance between both. Thus I have ordered a pair of Velodyne DD10’s to do some A/B comparisons with the Sunfires.

In the end, I will be a proponent for two subs instead of one for two channel music. While two is harder to integrate, the end result means lower volume translating in to lower distortion and more bass control. The room seemed better balanced and I prefer the subs next to my mains in a time phase aligned position consistent with the technology and design of the B&W 800D. By moving a single sub from the back corner to both subs to their new position next to the mains, I find myself more at ease with what seems to me to be a better paced and realistic bass performance. The subs seem faster.

Since I know that I will keep a pair of subs in my system, it is only a matter of which ones. One very positive option with the Velodynes is the remote capability. Once you tune for Rock, Jazz and Classical then store in memory, you simply push a button without leaving your listening position to instantly change sub settings as well as instantly mute if you like. Since I am very familiar with the software of the DD series I feel the Velodynes may beat out the Sunfires. But I will keep my mind open during the evaluations. Furthermore if the DD 10's eliminate the last remaining bit of bloat and give me the slam I need, I will consider it a complete success.

[Fife]

I too am a fan of two subs if set-up "properly". My setup is located here.
I find for 2 channel, my bass can be quite extreme so I too have to turn my sub volume down a few notches. The integration is pretty good especially for movies, rock, classical and DVD concerts. Because my B&W THX Subs (which mimic the Matrix 801 subs) are passive, I have found that they require good clean power. Using 2 channels from my Amp5 were good but I found the bass was loose. Once connected to my friend's Levinson 23.5, I was like :E :T :-y ;b>
Bass has never been better. I can play Tchaikovsky's 1812 overture loud and the canons are clear and amazing.

With my speaker setup, there are possible placement problems as my front l/r are attached to the subs.

A better placement for dual subs may be one in the front between the L/R speakers and one on the opposite side of the front L/R and on the side wall between the listener and front speakers.

Your mileage may vary but often there are two problems with getting subs to work in general: placement and crossover integration.

[Jesse111]

I am fully convinced two subs are better than one. I agree it's important to be very conservative with the volume. A sub must extend the mains not sound like another speaker. Then when moved next to the mains as if they are part of the mains, the bass intagrated very well. The timing and spacial coherance is obvious to me in this position. One thing for sure, I'll never go back to one sub.

Here's a pic of the final placement although before I got around to cleaning things up. I tend to make a bit of a mess when I'm auditioning and tweaking.

[Karma]

I am fully convinced two subs are better than one. I agree it's important to be very conservative with the volume. A sub must extend the mains not sound like another speaker. Then when moved next to the mains as if they are part of the mains, the bass intagrated very well. The timing and spacial coherance is obvious to me in this position. One thing for sure, I'll never go back to one sub.

Here's a pic of the final placement although before I got around to cleaning things up. I tend to make a bit of a mess when I'm auditioning and tweaking.

HI Jesse,
I'm with you on this one. I got my first subs in 1976 to go with my Dahlquist DQ-10's. I bought two subs and they were actively crossed over and biamped. Since then I have had several different speaker systems, all with dual subs and biamped. I now have two systems both with dual subs. Obviously, I think dual subs is the way to go.

Sparky

[Race Car Driver]

Yup, I am running dual subs as well. It allowed me to balance it out a bit, and turn them down, just to fill in the bottom end.

[Fife]

Hi Jesse,
I am surprised you do not have enough bass with your 501 and 800D. I would think that combo would be great for classical and rock. But whom am I to say since I dont own your combo.

[Jesse111]

Hi Jesse,
I am surprised you do not have enough bass with your 501 and 800D. I would think that combo would be great for classical and rock. But whom am I to say since I dont own your combo.

Enough bass is a personal preference. In fact, my system to me, does have the most dynamic and accurate bass I've ever heard. But the fact is, in order to get to 18 Hz a sub is necessary. But as my review of the Sunfires stated, my vinyl buddie prefers no subs. But for me, intagrating subs has proven to be a very rewarding venture.

Here's a few thoughts I had on that.

http://audiokarma.org/forums/showthread.php?t=90592

[Chris D]

I use dual SVS PC-Ultra subs for both 2-channel and mutichannel audio. (and HT) Works great, lots of power.

[Nick M]

I'm hoping to integrate a pair of subs into my 2ch setup as well.

I'm fairly sensitive to frequency peaks and can't do without equalized subs now (after using dual subs with a BFD in my last setup). Same goes for towers that have bass or midbass peaks in a given room. I'm also fairly sensitive to overdriven subs that have a lot of distortion/ringing. Classical pieces stand out the most to me, as cellos/percussion/organs often lack definition even in uber-expensive setups I've auditioned.

To me, the sunfire units make excellent space-saving rumble-boxes for home theaters, but they simply don't have enough authority or control for critical audio playback. The Velodyne Digital Drives are a whole 'nother story though. I'm planning to integrate a pair of DD-15's with my Paradigm Signature S4's sometime in the future (as cash becomes available). They have enough headroom to play cleanly at relatively-high SPL's, built-in parametric equalization capabilities for knocking down peaks (and smoothing out their crossover frequencies), as well as sufficient depth to truly flesh out the infrasonics found in many recordings.

As mentioned above, I used dual subs in my last setup with each unit placed next to my FL/FR mains (it was a dual-purpose HT/2ch system). Even subs with rock-solid cabinets and low-distortion output usually have some-sort of directionality to me simply due to the pressures they create. While I can't directly point out a good sub in a medium-sized room, I'll have no trouble telling you what side of the room it's on. A sub on each side of the room as close to the mains as possible eliminates this issue for me.

I'm getting by right now with just my S4's for most of my library, but I definitely miss my subwoofers. Authoritative response of pipe organs with 17Hz signals are awe inspiring. Once you have experienced it, the material only has a fraction of it's musical value with setups which can't reproduce those elements. Same goes for the relaxed ease that good subs can handle a double kick-drum hits or complex bass-lines that have even the best towers screaming for mercy.

The Velodyne Digital Drives are where it's at in my book. It's just a matter of coming up with US$6k-$8k for a pair of 'em... :lol: In my case it means an upgrade over the course of a couple years with all my other money-sucking bottomless-pit hobbies vying for the pork... (hahaha)

At low to moderate SPL's I think those DD-10's are going to be an amazing upgrade to the clarity and transparency of the bass you're currently getting out of the sunfires. Just keep the servo controls at their maximum level and spend some time tweaking the FR. Given your room size, I probably would have opted for the DD-15's (or 18's), but it will be interesting to hear what you experience with the 10's. Consider me jealous!

[Jesse111]

I probably would have opted for the DD-15's (or 18's), but it will be interesting to hear what you experience with the 10's. Consider me jealous!

I pretty much agree with your post. Interestingly I actually did have a pair of DD 18's. They were incapable of musical bass in my room. My audiophile buddy and I both tried but were unsuccessful intagrating them. The air volume was enormous but they were just not capable of the speed for critical music. The Sunfires can barely get by but they do perhaps only because of their enormous power and small driver. Thus the DD10 direction I am going now. I feel with the low mass driver while still using the same amp as in the 18, perhaps the musical speed of bass I'm looking for will finally be realized. The servo contro will most certainly be set at max but that may very a bit with some types of music ie. hard rock. One thing is for sure. Velodyne has seen to it that many ours of tweaking options are available and necessary to get the most out of their DD series.

For my taste, I've concluded that I'd not consider a sub over 10 inches. I feel Rel has a very good approach with their 10 inch and dual 10 inch driver designs as well. I've concluded in my mind the mass and air resistance is reflected in the speed in which these units can perform well for my taste.

Stay tuned for my opinion on the DD 10's. I should recieve them next week.

[Nick M]

Jesse - I can't wait to hear your review!

I started a similar thread over on the science forums regarding DD-10/12/15/18's in a 2ch setup. Having listened to (and thoroughly enjoyed)the DD-12, I was thinking about going with the 15's. Some of the bigwigs (like Velodyne reps and Ed Mullen) repeatedly said the 18's would be best. Indeed, Secrets of Hifi reports amazing low distortion at incredibly low frequencies and SPL's with the DD-18. We then got in a long discussion over cone inertia at various SPL's/Frequencies yadda yadda and everyone just quit on the subject. Of course how it sounds is the most important part.

I need to test them all out I guess. I may end up with the 10's or 12's myself if the 15's have difficulties with ringing/transients/etc.

I guess this year it will either be a pair of Digital Drives or a new 1920x1080p display. I may purchase my Digital Drives from a side-street dealer for the cost savings. Here is one place I was checking out...

http://www.digitalcraze.com/results1.asp?Manufacturer=44&Category=12

DD-10 $1700
DD-12 $2350
DD-15 $2950
DD-18 $3500

Not to shabby on the prices...
Of course it would be x2 for a pair.

[Nick M]

http://www.hypeaudio.net/item.aspx?eid=3&pid=105894

This place has the DD-10's for $1500 w/free shipping and a 30day MBG.
With the guarantee you know wou won't get stuck with a DOA, so at that price who cares if you have to dole out a couple bucks in the event you get a lemon that rears it's head after a few months.

Anyhoo, can't wait to hear how the DD-10's work out for you! :T

[Jesse111]

I saw those vendors on the net too but as you know they are not authorized dealers offering any warranty. But the 30 day money back deal would at least save you if there is something wrong form the factory that will show immediately like you said. I just can't bring myself to do it.

The folks at Velodyne recommended the same thing to me...a pair of 18's. However there seems to be more at play than specs here for some reason. At least for my ears, no matter how hard I tried the 18's just continued to break down imaging on critical two channel. They were just too overewelming in wave length and size to me. Finding an improvement with the small sunfires makes me very interested in the superior small Velodyne. Two tens will do the job of one 12 but with what I hope to be just a bit faster. I've gotten several emails from folks interested in the results as you are. So stay tuned!

[gianni]

Jesse111,

I completely agree about 2 subs being better than one in most cases. However, one thing I have found is that sometimes being located next to the mains is not always the best. I have seen them also work very well stacked in a position where you get the least interaction with room nodes. There are various articles on the web addressing this. Yes I do like the idea of locating the subs next to the mains, but if you have not tried stacking them in various locations, it might prove to be an informative exercise.

[alebonau]

I've got a DD15 I've got runnign withmy floorstanders and getting good results with it for 2ch music can only imagine 2 off them would only be better but neitehr have the dollars or the space to fit in two.

I heard a single DD10 and single DD12 instaore both of which I thought did a great job musically.

Will be interestign to read how you go jesse wihtthe two DD10s and how you find them musically.

[Eric_C]

I run dual subs. The ICBM creates a stereo LFE channel for me.

I'll be going down to a single for a while until I build the 2 new ones, see how the difference is.

[Jesse111]

Jesse111,

However, one thing I have found is that sometimes being located next to the mains is not always the best. I have seen them also work very well stacked in a position where you get the least interaction with room nodes. There are various articles on the web addressing this.

I would be concerned with time phase alignment but do you have a link to this information?

[gross30]

I tried positioning my DD-15's beside the mains and wasn't happy. Moved them across from the mains (approx 6') and found the results much more improved. I am very limited with where I can place my subs. Both my mains and subs are on sound anchors, and I like the results. (2) SUBS ALL THE WAY :T

[RobP]

Jesse, awhile back we spoke about the new Martin Logan Descent, well it looks as if they came out, here is a link for information on it, seems like I have to pay my dealer a visit. :T

http://www.us.martinlogan.com/display_speaker/descent_i.html

[Jesse111]

That thing looks like serious business. 700 watts per driver and the 25hz and 50hz db adjustment is interesting. Very interesting indeed. I like servo control and as you and I have talked before, you know I'm big on small drivers. 10 inch drivers are definately my prefered size for sub bass. Those 12 pound 10 inch drivers are most likely going to be fast and furious and hopefully quite accurate. Not to mention its quite handsome as well.

Are you going to get a chance to audition?

[RobP]

I think I will try to get up to my dealer this next week, I am really excited to hear it, I know that mine still suprises me everytime I listen to it. The current model is very acurate and is able to play low with oodles of control. I took a measurement the other night and I am fairly flat to 10hz in my 13 x 21' room with it. I cannot imagine what the newer model with more power will be capable of.
Did you also see the options on the inputs? very versitile.

[Nick M]

http://www.hpdirectav.com/item.aspx?eid=8&pid=105894

This eShop is C/Net certified, and offers a DD-10 with free shipping and 2yr CPS warranty for $1550.

The DD-12 is only $1675.

[Jesse111]

Did you also see the options on the inputs? very versitile.

I may be misreading it but it looks like it has line level RCA only but it has XLR and RCA for LFE. It seems the very few manufacturers offer XLR for line level.

Unfortunately connecting line level XLR output to LFE XLR input won't work.

[Jesse111]

http://www.hpdirectav.com/item.aspx?eid=8&pid=105894

This eShop is C/Net certified, and offers a DD-10 with free shipping and 2yr CPS warranty for $1550.

The DD-12 is only $1675.

They are still not an authorized DD internet dealer but with that CPS warranty you really can't go wrong. I kinda wish I'd seen those guys before ordering mine. I could have saved around 700 on the pair.

I just love the picture they have on their home page of the entire sky scraper as if that whole building is there's. :rofl: Nope, just renting a portion of just one floor most likely.

[Nick M]

Be sure to post pics of the DD-10's! I want all angles, close-ups, final positions in your setup, pics of small animals tumbling across the room with the soundwaves, etc. :lol:

When are you supposed to receive 'em? I'm definetly jealous! :?? :B

[Robert W]

New guy, great forum, few questions. Thanks!

Frequent browser here, this thread got me to register. I've been researching dual subs for a while. Recently I added an older M&K to my system and found that once calibrated properly that the sound is quite good. Don’t think I could ever go back to just 1 sub.

Anyway I have a dedicated HT / Music room in our new house that is in the building stage and have seriously been thinking B&W 800D's with 2 Velo DD-15's or 18's. Haven't decided yet. Demos where I live are non existent. I've owned / own B&W's and am quite happy with their sound though never heard their subs. I also notice that no one seems to mention them much….??

Reading through these and other forum threads have seriously got me in a sub woofer quandary though. I thought I had decided on the DD-15’s but now there’s the Martin Logan Descent i’s being discussed here that has me intrigued, and also I’ve been reading a very long thread on the AVS board about the new JL Fathoms F113’s that are supposed to be the end all of subs today.

Yes I know this stuff is all subjective and what sounds good to one may not to the other person. Personally I like my EP600, it’s quite a good sub for the $$. However the dedicated media room is going to get the best as it will be something that I live with for ever.

Any opinions from any one that has heard these subs would be welcome. I know that the Descents haven’t been out long enough but some of you I’m sure have heard a few of these subs. Room is 27’x21’x10 and will be used primarily for 2 channel listening. Movies too but music is more important.

So what do you think? 800D’s with 2 ??? Velo DD-15’s , DD-18’s, B&W ASW855’s, JL Fathom f113’, or now the ML Descent i’s….so many decisions!

Thanks guys…..great forum.

[Nick M]

Going from Axioms to B&Ws is going to be a big change in response character for sure!

One tidbit I can offer is that the ML Descent offers a 2-Band EQ whereas the Velodynes have an 8-Band. Depending on your room size and where your peaks/nulls are, this could make a huge difference!

I've listened to the DD-12 and loved it. My last setup was dual-purpose HT/2ch and I used twin SVS 16-16 PC+ subs. While many of the respected names in audio claim that the 15" and 18" are the way to go, we see that guys like Jesse have had trouble blending them into a 2ch setup.

When trying to explain why this is, there are a whole mess of variables that must be taken into consideration (not just amp-juice, and cone size). We don't have all the variables defined, so looking past this, the point is that people are noticing a difference in clarity/integration between the bigger DD's and smaller DD's. I may very well end up going with dual 10's for my setup after I do some extensive auditioning.

You might want to consider taking some time off and visiting a good shop to compare products, especially if you're talking about spending upwards of $20k on gear.

[dknightd]

I'd prefer to have two subs. And I'd prefer I could remote control their volume. I'm leaning toward two dd10s. But alas I don't have the money for that yet. I'll have to decide, get two cheaper subs, get one sub now add another later, or wait till I can afford what I really want and see what is on the market when that happens.

[Nick M]

Save, and buy what you really want! :T

[Robert W]

Yes, big difference from B&W 800 series to the Axioms, but I have a pair of 704's that have had to have the midrange replaced twice. That's why I went the Axiom route. That and the deal with the wife is that the rest of the house be finished first (it is now) before I started on "my" room. To tell you the truth for me anyway, side by side there is very little difference between the 704's and M80's.

But back on topic. I have heard the 800's and they are wonderful. But still lack the bottom end that I have come to enjoy. Don't really need loud in your face thumping bass so to speak, but rather musical soundstage and depth / clarity. Hense the need for dual subs. The room has always been planned for this.

With all the recent developments in sealed design I start to think that maybe 10 - 13" sealed subs would provide enough of what I want. Space and WAF is not a factor and I keep reading reviews that claim better musical response with sealed design. But I also think that the 800's might very well cover the punch and lower end in the 30 - 50hz range. So since they already have 10" drivers I keep leaning towards the DD-15's or 18's for the real low end.

The trouble with demos for me is that it's literally a days drive or more for me (each way) to find any dealer that has this kind of equipment in stock. Then trying to find one that has everything that I'm interested in is another story entirely. Have to do as much research first then maybe a road trip is in order.

Anyway if some one gets to hear the ML Descents, or the JL Fathoms please post a review.

[Chris D]

Yes, pictures of Double D's are always welcome. (or triple D's, or whatever)

[Nick M]

Jesse - Well, did you get 'em yet? I've got enough clams set aside for one, but I'm going to wait until I have enough for both before I order. Perhaps after income taxes I'll have enough for both...

I made a couple mock-up 11.75"x11.75"x13.5" boxes from cardboard and duct tape to see how they (dual DD-10's) would fit into the system physically. Hopefully Sunday I'm going to go and compare the 10 and 12" units. I'm actually leaning towards the DD-10's like you, and can't wait for your review (and photos!).

I called up the bargain sites above, and found that the only colors offered on the last two links are black lacquer. Considering that my 'Digm S4's are finished in rosewood, I think the black lacquer would be the only color I would want anyways.

[Jesse111]

Be sure to post pics of the DD-10's! I want all angles, close-ups, final positions in your setup, pics of small animals tumbling across the room with the soundwaves, etc. :lol:

When are you supposed to receive 'em? I'm definetly jealous! :?? :B

I love sharing system pics so you can count on it!
I will receive them this coming week. They were shipped out this past Wednesday.

Frequent browser here, this thread got me to register. I've been researching dual subs for a while. Recently I added an older M&K to my system and found that once calibrated properly that the sound is quite good. Don’t think I could ever go back to just 1 sub.

Ah yes, a confirmed dual sub man. We’re always looking for a few good men. And welcome to the forum. :T

Anyway I have a dedicated HT / Music room in our new house that is in the building stage and have seriously been thinking B&W 800D's with 2 Velo DD-15's or 18's. Haven't decided yet. Demos where I live are non existent. I've owned / own B&W's and am quite happy with their sound though never heard their subs. I also notice that no one seems to mention them much….??

For music I wouldn’t recommend anything over 12 inch. But as you have read in this thread I feel the 10’s are the best way to go. Same amp and much lower mass. But some may argue big drivers move with less throw. However, with dual 10’s I can’t imagine running short on bass for HT. However, I suppose if your room is very large and you are primarily HT then 15’s or 18’s may be your choice. I’ve auditioned the 18’s in my dedicated sound room and found them impossible to integrate with my 800D’s for music. Keep in mind that I am pure 2 channel music only. The huge wavelength and air movement was just not musical. Perhaps in a gymnasium.
As for B&W subs, surprisingly they seem to have a reputation for the HT sound by many folks. Some really like them for music. I find them to be a good sub but not great for the money.

I thought I had decided on the DD-15’s but now there’s the Martin Logan Descent i’s being discussed here that has me intrigued, and also I’ve been reading a very long thread on the AVS board about the new JL Fathoms F113’s that are supposed to be the end all of subs today.

However the dedicated media room is going to get the best as it will be something that I live with for ever.
Room is 27’x21’x10 and will be used primarily for 2 channel listening. Movies too but music is more important.

So what do you think? 800D’s with 2 ??? Velo DD-15’s , DD-18’s, B&W ASW855’s, JL Fathom f113’, or now the ML Descent i’s….so many decisions!

Thanks guys…..great forum.

Your room size is close to mine. The 800D is the most realistic, spectacularly emotional speaker I’ve ever heard. The bass is extremely accurate and realistic. The 800D bass response is place sensitive in a room. I will give exact placement of mine later for anyone concerned. I am of the opinion that the DD 15’s and 18’s simply can’t keep pace with the 800D. Although the Descent may prove to be a spectacular performer, my ears have come to prefer time delay and phase accuracy as regards placement. In other words, placing forward firing subs next to my 800D’s in the proper place offers me better integration and musical accuracy. That can’t be done with subs designed for corner placement several feet behind the mains and/or multidirectional drivers. But the thing is, you may prefer corner sub position and the corner designed subs like the Descent over the time phase alignment position of forward firing subs. It is an established fact that sub placement in a corner will give more bass and integrate easier into a room than subs placed somewhere towards the inner part of a room (ie. next to the mains). But Velodyne’s software has greatly improved on that problem.

For HT, corner placement is a must. But for me, time phase alignment is the priority I choose for my music.

[Jesse111]

Jesse - Well, did you get 'em yet? I've got enough clams set aside for one, but I'm going to wait until I have enough for both before I order. Perhaps after income taxes I'll have enough for both...

No not yet, but maybe as soon as Monday. 8)

I made a couple mock-up 11.75"x11.75"x13.5" boxes from cardboard and duct tape to see how they (dual DD-10's) would fit into the system physically. Hopefully Sunday I'm going to go and compare the 10 and 12" units. I'm actually leaning towards the DD-10's like you, and can't wait for your review (and photos!).

Excellent idea on the mock-ups. Did you draw in a nice big driver and write Velodyne on the bottom with a blue marker? Someone may accuse you of mocking up some Sunfires. :lol:

Intagrating dual subs in the middle of a room is painstakingly fun but time consuming. It'll take me a couple of days but I'll be dropping in with small updates as I go. I'm pumped and ready.

[Nick M]

LOL, no I didn't draw in the drivers and logo (haha). I've set up and equalized (with a BFD) dual sub before in my previous setup. It definetly takes a little while!

Looking forward to the thoughts and photos next week.
Have fun.

[Karma]

With all the recent developments in sealed design I start to think that maybe 10 - 13" sealed subs would provide enough of what I want. Space and WAF is not a factor and I keep reading reviews that claim better musical response with sealed design. But I also think that the 800's might very well cover the punch and lower end in the 30 - 50hz range. So since they already have 10" drivers I keep leaning towards the DD-15's or 18's for the real low end.

HI Robert,
I have been using dual subs on various systems since the mid-seventies. I have learned a little about what works and what doesn't. I currently have two systems; a main system used strictly for music in my main listening room and a 5.1 HT system in my bedroom. Both systems have dual, biamped subs.
Both systems offer outstanding bass. OK, enough of establishing credentials. Let's now talk about real world bass integration problems and solutions.

Subs are band aids for mains that don't have deep, powerful base. 800's are not that type of speaker. They have wonderful bass.

Most true full range speakers are very difficult to integrate with subs, no matter the maker. Think about what you are doing. The 800's are rated to 32 Hz. All but the very greatest subs (very expensive) will only go to slightly below 20 Hz. With proper overlap, the subs will cover the range of from about 32 to 20 Hz. That's 12 Hz, or slightly more, of range devoted to the subs. The crossover slopes and natural roll off will never allow the subs to operate in a linear amplitude range. About the time the subs are approaching linearity, they start to roll off again. You end up with a hoseshoe shaped frequency response from the subs. No good. They will never operate in a linear frequency range.

For comparison, my 805S mains are used with dual ASW800 subs in my bedroom 5.1 HT system. The 805's naturally roll off around 50 Hz. I use the foam port plugs which raises the low frequency roll off to around 60 Hz. I do this specifically to ease the integration problem. This gives the subs approximately an octave and a half of operating frequency. It's not ideal but much better than the integration issues faced by 800 owners. The 805's are speakers that can be be successfully subed. My system bass performance is outstanding for all types of program material.

If it were me, and I had 800 mains, I would get some Velo 18 inch subs and use them strictly for HT. I would not let them overlap the 800's bass at all. I would not want to mess up the 800's beautiful bass performance. For HT, all we really want is good solid thuds, bumps, and bonks from the subs. Since the vast majority of music recordings do not have extreme bass, the subs are not needed or wanted. For music, the 800's native bass performance is better than good.

If you can't live with this, buy some mains that have less impressive bass performance. This will give you a real chance of good integration and save a lot of money. Then plan on using the subs for both HT and music. This is a viable way to get great overall system performance for all types of program material.

Do not screw around with small subs. Either buy serious subs or forget about them.

This is just my view but it is backed up with about 30 years of experience. And I follow this philosophy with my systems. It works.

BTW, I love great bass. I am not a wuss when it comes to moving the walls. Not at all.

Sparky

[Nick M]

It's easy to find a sub that will hit well into the infrasonics in a moderate sized room. What's difficult is finding one that has the features of the Digital Drives that allow a nice clean setup outside an anechoic chamber while also keeping distortion low.

The EQ software/hardware is essential for me (a dedicated BFD user in my last setup). I have an annoying peak in my room around 50Hz and a couple smaller ones above and below that. It works great for the large bookshelf speakers I have helping their tail-end, but makes unequalized towers and subs sound like doo-doo. Extensive room-treatment not being a viable option, an EQ is the next best thing.

My twin SVS 16-46 PC+ subs had no trouble hitting infrasonics down around 12-14Hz at SPL's in the 100dB range. Plenty of films have info in this range, and many music selections get down into the upper teens. I also find that having a system with an extension this low makes the frequencies in the 20's and 30's sound much more effortless and natural. The SVS units had so much headroom in my sub-2000 cubic foot room that their distortion was imperceptible. Only trouble was that they seemed to "ring" or "roll" a bit with things like slap bass where the lower end moved around so quickly.

I believe the "wavelength" is the same for a given frequency whether it comes from a 10" driver or 18" driver, just one needs to work harder (greater cone excursion) to displace enough air to create that wave at the desired SPL. One thing I do notice is how those waves sound/feel and I'm not sure why. For instance, I vastly prefer the multiple 7" bass/mid-bass drivers in the slim-cabinet of the Paradigm Signature S8 or B&W 803D to say, the larger bass drivers in the 802D's. I notice this effect the closer I get to the speakers. I believe it has to do with the physical dispersion of the wave, but I'm not a physicist (althouh I did take a semester of physics w/calc in college, I've never really read any audio engineering books). Paradigm & B&W both claim that multiple drivers in a narrow cabinet help with this issue. I think the same can be said for massive cones in subwoofers vs multiple smaller cones.

Anyhoo, B&W doesn't make a single tower/bookshelf that reaches with authority into the low 20's/upper teens. I find that range essential for many of my recordings, and also for the ease at which they produce frequencies in the 20/30/40Hz range. In my listening space I like bookshelves that can get down around 60Hz, and then subs that can cleanly take over down into the soul-shaking range of pipe organs.

Just a difference of experience and opinions I guess. I'm hoping that with smaller subs I eliminate that overpowering effect that I get - similar to having big imposing towers to close to your chair regardless of SPL. Given the sealed/servo controlled design of the sub (and high muscle to mass ratio) in my relatively small room, I'm shooting for very-low distortion and ringing as well. Only thing I'm worried about is their extension. So long as a couple of them can reproduce 18Hz frequencies at moderate SPLs with the servo settings cranked up I'll be happy. The EQ and adjustable XO capabilities are a no brainer for my demands.

[Robert W]

Thanks for the replies gentlemen.

Karma - One of the primary concerns that I’ve had is exactly what you speak of. That being crossing over into the 800’s range with the subs. It’s a tough decision for me to make because as I have mentioned demos are all but impossible. I heard the 800’s while traveling last year, though without any sub and found them to be wonderful. However as with any other “full range” speaker that I have ever heard I definitely thought that the low end that I have come to love so much was missing. This may have been a product of under amping, I don’t know. Can’t remember what amps the place had hooked up. (Bryston or Krell??) I would love to hear them with either Classe or Mac monos. I am going to try and achieve that soon.

I have also though about going the 802 route just because of the sub integration issue, but if I did that I would always wonder if I shouldn’t have.

Quite a bit of the music that I listen to reaches well down into the low 20s or below.

I realize that it’s apples/oranges and the room that they are in is an acoustical nightmare….but my Axioms are rated to 34hz, though I’m not sure I buy that after listening to them, ….anyway after some tweaking with sub placement, crossovers and phase everything sounds quite good with the mains run full and the subs crossing over at 60hz (EP600) and 80hz (MX-200). My thinking is that in most real world situations even B&W’s specs are probably going to be a bit different from what I actually see/hear. I would bet that the 800’s sound awesome to about 40hz and then roll off. Hence my thinking that I will want to integrate the subs into that range. Maybe I’m way off. Tough to tell till I get them in my home and listen. But I’m still leaning towards DD15’s or 18’s. I can always just use the lower end of them if I find the 800’s to be enough. There will also be bass shakers integrated into the raised seating for HT.

As for small subs, yeah probably not. But the JL Fathoms at 13.5” still look interesting. People are drooling over them, rave reviews....but that may just be the new kid on the block scenario.

Jesse - The room is being built from the ground up and will be completely treated acoustically. This will make a big difference as far as trying to get the subs / mains to sound proper together. I’m 99% sold on sealed designs.

Also could you elaborate on this: “I am of the opinion that the DD 15’s and 18’s simply can’t keep pace with the 800D.”

What do you think would be better? For Music. One of the primary reasons for thinking Velodyne for me has always been that they are servo controlled and I have read nothing but great things when it comes to music about them. They are sealed and with their software control I would think that they would be best for forward firing integration next to the mains. I do not want to go the route of having to worry about placement, ports, muddy, bouncing off walls, standing waves etc etc. Though I realize we all have our own tastes I’m pretty sure that the Velos represent the best way to go with what I am looking for. Have you heard the two together?

It’s funny to research this stuff and reading all the different opinions. One of the things that I’ve noticed is that there seems to be two camps on size. Some that say a bigger 15-18” sub can’t keep up, and others that say a 12” can but can’t give the SPLs needed at real low end, can't move enough air. Though I think a LOT of it depends on the room and treatments.

Seems that it’s like everything else though. Every one always thinks that the grass is greener with_______. 

Thanks again guys, much appreciated.

Robert

[Jesse111]

Nicholas and Karma are much more technically educated than I am. They both are offering very good knowledge and advice. But one thing is for sure. Everyone hears different. That's why so many different opinions. Even peoples ears make a difference. Put your fingers behind your ears and push them out just a bit. The entire sound of your system changes.

I find the 800D to have the most accurate bass I've heard. No, it doesn't produce sub bass but I feel this is a plus. I've never much cared for the idea of one driver doing duty for 20hz up to 350hz and more. I believe B&W has done an incredible job of assigning the best frequency range to each driver to produce the best music from any speaker in it's price range and even much more.

I disagree with Karma. But that doesn't mean he's not correct. The fact is, he's correct for his ears. I am looking for real music that is correct for mine. When I go to concerts or recordings I hear things that no full range speaker in the world can produce on its own, but that is what I want. While speakers like the Wilson Watt Puppy 7 bass impressed me at first, I found myself suffering with fatigue after less than an hour of listening to them. So since I will always have sub woofers in my system, I chose to get the best speaker on the planet that played music from around 30hz on up. That turned out to be the 800D for me. It is distorton-free in my opinion. I can listen for unlimited time. I audtioned the 802D and the difference was immediately noticeable. If you can afford the 800D, get it.

I feel I have achieved true real world sounding intagration with dual subs with the 800D and it is spectacular. But I could not do it with DD 18's. Perhaps for your ears you can. The intagration of the subs has not only thickened the emotion of the low end but actually added depth to the sound stage by supporting and enhancing imagery of the bass instruments especially the drum kit in rock music. That could not be happening if I was introducing distortion, bloat or overhang. The difference is subtle. But that is the goal. A sub should not transform the sound of full range speakers. Especially with the quality of the B&W 800D. They should only extend them, enhance them and add realism. It can be done. I don't know how to explain it but for me it works better with smaller drivers. Drivers more closely related to the size of the main speakers seems synergistic to me. More of an extension instead of an addition.

I have found the perfect placement for my 800D's in my room. The bass is very impressive and some of my lesser audio ear'd friends can't believe it when I tell them the subs are off. When I turn on my subs there is very little difference but the difference is definate nonetheless. No one says "WOW feel that bass?" No, instead you see the kick drum in the stage become more visual. You see the stand up bass closer to you. That's what correctly placed, high powered quality subs will do. If you go in to a dealer and he turns on a system and the first thing you think is "wow, that's incredible bass". I can almost guarentee you that that will be the first thing you come to hate about that system. Same with bright stunning highs.

I'd also like to add that I don't believe any sub can accurately handle frequencies for music above 40 or maybe 50 hz. They just don't control those higher frequencies well enough while handling 20hz and below. But that would depend on what quality of speakers a person has been exposed to. If you've never heard true quality bass performance like the 800D setup properly then you may feel subs do well at those frequencies. I'd never consider bookshelf or any speaker for that matter configured through the crossover of a sub and crossed at 50, 60, 70 or 80hz. It may sound better than with no sub based on one's experience and in some circumstances but I personaly woudn't enjoy it. Because of the truly high end bass perfromance of the 800D, I could never go that route. The 800D is phenominal above 30hz.

The 800D in most cases is set up completely wrong in most dealer show rooms. I've seen them and it's pitiful. If you were to come to my room you'd think you were listening to a different speaker than if you went to my local dealer and heard them there.

[Karma]

Removed post.
I decided that you have made your mind up and don't need my advise. Good luck.

Sparky

[Nick M]

Jesse - Did you get the subs?

[Nick M]

Subbage Yet? I need pics and a review! :B

[Jesse111]

Subbage Yet? I need pics and a review! :B

Dual Subbage has arrived.

Arrived yesterday. Plugged them in and letting them get to know their new friends - Bowers, Wilkins and Mac. Already took a few pics. I'll start a fresh thread Entitled "Dual DD 10's" in the next few hours with the pics.