[turkey]

Nope.  As good as they are, they are still box speakers, and thus would not work well in my room.

So CD monopoles won't work, but non-CD dipoles will? What characteristic of your room makes this so?

[Tyson]

Bass gets unmanageable below 200hz in my room.  And the V2's do have a waveguide on the tweeters, so they are better than my last few speakers in this respect (although probably not as good as the Geddes - would need better measurements of the V2's to know for sure). 

[doug s.]

Bass gets unmanageable below 200hz in my room.  And the V2's do have a waveguide on the tweeters, so they are better than my last few speakers in this respect (although probably not as good as the Geddes - would need better measurements of the V2's to know for sure).

tyson, it seems that gedlee's, with multiple subs per earl's recommendations, might be yust the ticket for a difficult room such as yours.  or, even w/your present speakers, another pair of subs to the side or behind the listening position might also help...

doug s.

[jtwrace]

tyson, it seems that gedlee's, with multiple subs per earl's recommendations, might be yust the ticket for a difficult room such as yours.  or, even w/your present speakers, another pair of subs to the side or behind the listening position might also help...

doug s.

This is an approach that I try anyway if I decide to not go with the Abbey's.

It just makes sense...

[Tyson]

Subs are not an option from a WAF perspective.  Plus, distributed subs are only a solution for the under 100hz range, and my problems start at 200hz.

[Tyson]

Besides, open baffle bass has a completely different presentation of the bass area.  To my ears it is simply more correct sounding than box generated bass.

[jtwrace]

and my problems start at 200hz.

Tyson-

It "sounds" like you need some bass traps. 

[Tyson]

Why?  The V2's solve my bass issues completely, and their bass sounds better than any box speaker I've heard, even ones in dedicated rooms with full treatments. 

[jtwrace]

Why?  The V2's solve my bass issues completely,

Oh.  I didn't realize that was the case.

and their bass sounds better than any box speaker I've heard, even ones in dedicated rooms with full treatments.

I think that the "box" with a properly treated room would shock you.  I'm surprised that you think your room couldn't still benefit from treatments.  Have you measured your in room response? 

 

[Bear]

hmmmm,  super v's or abbeys with dibole servo subs ala Toms and Mgalusha....?  Does anyone know where the super v's cross to the servo subs? 

[ebag4]

hmmmm,  super v's or abbeys with dibole servo subs ala Toms and Mgalusha....?  Does anyone know where the super v's cross to the servo subs?

About 200 Hz.

Best,
Ed

[goskers]

I still don't really know why dipole sounds different than monopole.  Considering that bass is attempting to pressurize a room I would make the assumption that the most efficient way to do this is the best.  Dipole is far from the best method when it comes to pressurization.  My theory as to why people tend to prefer dipole bass is that where monopole has one output, dipole essentially has two.  If you look at it from this rationale then it makes complete sense as the more sources the better from an even bass stand point. 

Does this make sense to anyone else??

[cujobob]

I'm not sure why Earl struggled to impress at the show previously...it could just be the appearance making people believe they aren't impressive.  I've heard comments that his electronics (the old Pioneer receiver) and normal speaker wire were also partially to blame... I think it's just affecting their judgement.

Multiple subs are the best way to get great bass in any room, no matter how difficult..but if it isn't an option, open baffle is a great compromise.  I use an open baffle servo sub because of the convenience, mostly.  It sounds wonderful and many people are using multiples with their Gedlee speakers.  I think multiple OB subs guarantees great bass for anyone who doesn't feel like tinkering with measurements too much.

[goskers]

My question or statement was directed more towards why people think that OB bass is the answer to a room problem.  The only things that make sense to me is the fact that OB actually makes a single source into a dual source and the fact that OB doesn't pressurize a room nearly as well as other types. 

I already have a full Geddes system complete with BP subs so I don't need to be convinced.  By the math, multiple subs are the only way to go if you want to have a multi-seat room that sounds good.

[TomS]

hmmmm,  super v's or abbeys with dibole servo subs ala Toms and Mgalusha....?  Does anyone know where the super v's cross to the servo subs?

The Super-V's use the 12" OB servo drivers as both woofer (up to 200hz) and subs since they go down to the 20's. 

I have 2 dual open baffle servo subs and a single sealed servo sub in my setup.  MikeG has 3 sealed servo subs.  I don't use electrical high pass on the Abbeys' so the 12" driver performs woofer duty until it starts to roll off naturally at 80-90 hz.  The OB servos take over from about 80 hz down.  The sealed sub takes care of about 45-50 hz down.  All of the sub amps have subsonic filters so there is a very low cutoff high pass filter on them as well.

My room is rectangular with a flat ceiling, so I have predictable and measured modes at about 23, 42, 76 hz (and of course multiples).  I believe they are pretty much all excited to some extent regardless of whether I use the OB's, sealed subs, or both.  Distributing them throughout the room and adjusting the phase evens it out some, without too much fuss.  I quit obsessing about getting it ruler flat as long as the averaged response right around my single listener position is decent.  As a result, it sounds quite good as is.

[poseidonsvoice]

The Super-V's use the 12" OB servo drivers as both woofer (up to 200hz) and subs since they go down to the 20's. 

I have 2 dual open baffle servo subs and a single sealed servo sub in my setup.  MikeG has 3 sealed servo subs.  I don't use electrical high pass on the Abbeys' so the 12" driver performs woofer duty until it starts to roll off naturally at 80-90 hz.  The OB servos take over from about 80 hz down.  The sealed sub takes care of about 45-50 hz down.  All of the sub amps have subsonic filters so there is a very low cutoff high pass filter on them as well.

My room is rectangular with a flat ceiling, so I have predictable and measured modes at about 23, 42, 76 hz (and of course multiples).  I believe they are pretty much all excited to some extent regardless of whether I use the OB's, sealed subs, or both.  Distributing them throughout the room and adjusting the phase evens it out some, without too much fuss.  I quit obsessing about getting it ruler flat as long as the averaged response right around my single listener position is decent.  As a result, it sounds quite good as is.

I'll throw in my hat and state that my subwoofer setup is similar to Tom's and we've freely e-mailed each other and exchanged these ideas. I use a pair of U-frame subs (using a special Shiva-X 12 inch which has a higher Qts of 0.6), they are crossed over at about 90 Hz. Recently, I have been in receipt of a sealed Rythmik servo sub, which will be crossed over at about 45-50 Hz but the actual crossover point remains to be determined after some measurements are completed. Even without the Rythmik, I had a response of +/- 4 dB from 30 Hz to about 200 Hz. I just didn't have much output below 30 Hz so I recently got a used Rythmik. The Abbey's run full range just like Tom S's setup. Even at 100+ dB at the listening position, that 12 inch driver on the Abbey barely moves. Tom's system will most definitely sound better than mine because he has a better room (aside from any electronics differences). The goal is to get the best room you can. Although these speakers do FAR better than most others in small rooms due to their narrow CD response, they will thrive in a larger room that is well treated from the ground up. That's my goal and it should be a reality by next August/September, fingers crossed.

Anand.

[Tyson]

Box subs radiate in an omnipolar fashion.  This means the bass is bouncing off all 6 surfaces of a room (roof, floor, front wall, side walls, rear walls).  Open Baffle bass radiates bass in a figure 8 pattern, so it eliminates the side wall re-inforcement and nulls.  Not a perfect solution, but certainly a good solution.  IMO, you want to excite room modes LESS, not more, in an ideal world.  Having multiple subs excites MORE room nodes, but they are spaced at closer intervals, so don't sound as offensive.  But, a room mode is a room mode, and they are best avoided, where possible.

[sts9fan]

That's not reall correct Tyson. All a room mode does is cause uneven response. By exciting more modes you even that out. No harm no foul.  Your room is already overun with high frequency modes so what's the diff?

[Russell Dawkins]

I see it pretty well exactly as Tyson does, if I read him right.

[poseidonsvoice]

Box subs radiate in an omnipolar fashion.  This means the bass is bouncing off all 6 surfaces of a room (roof, floor, front wall, side walls, rear walls).  Open Baffle bass radiates bass in a figure 8 pattern, so it eliminates the side wall re-inforcement and nulls.  Not a perfect solution, but certainly a good solution.  IMO, you want to excite room modes LESS, not more, in an ideal world.  Having multiple subs excites MORE room nodes, but they are spaced at closer intervals, so don't sound as offensive.  But, a room mode is a room mode, and they are best avoided, where possible.

I see it both ways. However, one method is far more inefficient, requires equalization, has reduced SPL capability etc...than the other method  when comparing a similar driver (optimized for the right Qts of course) in a sealed/vented enclosure. You pick your poison and I've heard both types and can enjoy both types as well. But if value is of concern for that one variable alone, then dipoles are going to be more expensive. But value is a parameter which is variable from one client to the next.

YMMV,

Anand.