Velodyne Digital Drive Series subwoofer in stereo

Au contraire, the tone of my last post was intended to put some reality into the guys who were bashing Truthseeker personally without offering one shred of backup other than their own unique "experience". And they still aren't, other than the "magical human ear" theory - which is far less plausible than the "magic human imagination" theory, formerly known as the placebo effect, or the out-of-phase sound effect.

The 65 Hz crossover point was custom chosen for me to match my speakers by Velodyne themselves at LOWER than the stock sub's point. And obviously it's not an infinite slope crossover so my mains are operating well below 65hz. The stock Velodyne DD-18, by the way, has a fixed, built in high-pass at 80hz. But I guess there's people here who know more than the Velodyne engineers.

Quick quiz - Do you know how low 65 hz. actually is? It's the very LOWEST note on a cello or a BASS trombone. Tenor trombone's lowest is 82 hz. The very lowest note written for a human bass voice is the same. Low E on a Guitar is also at about 82hz. Timpani - 87 hz. The very LOWEST note an acoustic double bass or bass tuba can possibly play is about 42 to 44hz. And nearly all the notes played even on double bass or tuba are above 63 hz and up to 300 hz. They're not down there banging the low E in every measure.

So what kind of bass are you all talking about? Exactly what instruments or pieces of music sound so much better in "stereo" bass? Organ and Tuba duets?

Quick quiz ..have you ever tried it? Most of the nay sayers are the same people who have never tried stereo subs. Also you've forgotten the Piano goes deep into the 20 Hz range. Oh I forgot the Piano's not a musical instrument either... right? Or you'll give me your theory on why I or anyone else shouldn't be able to detect it's presence in stereo..right.

What if I had 3 bassist in the same recording from left to right. You trying to tell me the stereo subs can't differentiate between the right and left player? Even at the lowest frequency of 41 Hz. I've already tried this using indentical subs. Both subs responded at different times depending on who was playing. Apparently there are recordings with the lowest notes in stereo on some cds.

It's possible to have this in a movie track. Why do you not believe it's possible in some other recordings? I guess some people know more than the engineers of Lexicon and Meridian who have mutliple sub outputs just for such a thing.

Next thing you'll tell me is that bumble bees can't actually fly. Because there's not a shread of evindence that suggests otherwise. Me and 4 billion other folks just imagine seeing them fly ..right.

First of all - I'm not saying there's anything WRONG with having two subs. It may make placement (which is the REAL issue people should focus on with subwoofers) easier in some rooms. And yes, I did have two smaller 12" Velodynes before I sold them to go with a single larger one, which I keep in a slightly off center position - not in a corner.

The reason you have the potential for multiple subs for movies is because some DVD's may place bass tracks in multiple locations - intentionally WAY out of phase for FX purposes - not for music. You can hear that because two sub channels may be mixed 90 degrees apart. But we (at least I) haven't been talking about DVD/Home theater, which I have no interest in. Perhaps I should have been more specific.

As people have said above, the STEREO location of a piano, for your example, even at the 27.5hz Low A comes from the ample myriad of higher pitched overtones that ONLY arrive through the mains. Good subwoofers (if set up properly) playing NORMALLY recorded music, especially on LP - which is all I listen to - are fed no recognizable stereo information through the crossover to transmit. It isn't there unless intentionally placed by the engineer using digital delay effects - like done in a DVD.

In a true musical stereo recording, the pure bass frequencies cannot arrive at the mics far enough out of phase to be audibly placed - only the overtones can. Even in what is called an "exaggerated separation"/ "ping pong" effect by engineers, 2 stereo mics are placed maybe 10 feet apart with a 3rd one in the center. Even assuming the lows aren't later panned to the center during mixing (which they are), the TRUE bass might be out of phase enough to jump a needle from the groove, but still not enough for you to guess where it's coming from.

re: "Both subs responded at different times depending on who was playing. Apparently there are recordings with the lowest notes in stereo on some cds." Or, as you said earlier, "I can put my hands on each driver simultaneously and feel them vibrate at different times on the same tracks."
- - - - Of course you can! Nobody said the recorded signals to both channels are identical - but that doesn't at all mean if you had your eyes closed (and didn't already know the music) you could point to where the bass is coming from.

Anyway, I give up on this one... there's no argument that defeats the Magic Ear theory.

re: Bumblebee flight

From Straightdope.com:
"The basic principles of bumblebee flight, and insect flight generally, have been pretty well understood for many years. Somehow, though, the idea that bees "violate aerodynamic theory" got EMBEDDED IN FOLKLORE."

From David Wilkinson of Quarksoft:
"bringing two wings flat against each other and then moving them apart, very strong vortices were produced which could generate unexpectedly large lift. The earlier "disproof" was based on an inadequate model but THE STORY HAS AN INSTANT AND LASTING ATTRACTION TO THE NON-TECHNICAL MIND."

'Nuff Said.

re: Spacekadet's original post -

Well, since I don't know much about DVD/Home theatre I just called Velodyne tech support directly - and they completely agreed that there should be no "stereo" advantage in having 2 subs. He stated that, even for home theater, the only advantage of 2 subs is, depending on the room, having a smoother response curve attainable across a very wide or deep seating area. He specifically reiterated that the frequencies emanating from a DD-12 or DD-15 are completely non-directional for movies or music. I'd trust the manufacturer more than some Audiogon knowitalls (like me, for example).

He also said that the bass output from one DD-12 is about the same as two DD-10's, so it's (IMHO) an insane waste to buy 2 DD-10's at $2,000 each instead of one DD-12 at $2400, or one DD-15 at $3,000.

Opalchip...LOL..I really enjoyed getting under your skin.
No doubt your very brilliant. It's been a pleasure.My only point is, I as well as others enjoy what stereo subs do for the music and movies.Thanks for all the great info.Will it stop me from ever using two subs again..not hardly. Just like a die hard tube fan, we all have our preferences whether anyone else likes it or not.
It may not be sane for some.But hey there's nothing really sane about the hobby anyway.Lighten up.. it's only audio.

Good listening!