One test my 20-39PC+ failed. (1 Viewer)

[Michael R Price]

After I thought about it I realized I was being an idiot. Of course the drivers have to be electrically out of phase for the distortion to be cancelled.

 

[Jason Brent]

Is a push pull arrangement similar to isobaric?

 

[ChrisWiggles]

yes i believe so.

edit: i can't spell

 

[Robert Cowan]

simply put, if a subwoofer shakes so much that a nickel falls off one COULD assume that its not tranmitting 100% of its energy into the air, that its absorbing some of it. you could argue that the most efficient sub made would have NO cabinet vibrations at all. all acoustic energy is transferred into the air, rather than the cabinet. thats what the test does. it relates to efficiency, not necesarrily to how good it is.

if a ferrari was only 50% efficient, it would still blow away a stock car that is 95% efficient... BUT, the ferrari could be better if it were 95% efficient...

 

[Mike SJ]

I remember my dad putting nickels on his Altec Voice of the Theater speakers and cranking them way up. but the enclosures were folded horn and not sealed. Now Martin Logan Descent has tried to combat the loss of energy through cabinet vibrations by situationg 3 drivers facing out in a "equilateral triangle" setup. I can see how this works but IMO their cabinet is too small, and I would think the cabinet itself takes care of the vibrations. it would be neat to see a TUMULT version of this....well I guess on to the DIY section.

 

[Jesse Sharrow]

Bill: That metallica DVD-Audio has no sub out. It sounds great. But it has no sub out. I think mine is messed up though.

 

[Bill Blank]

Jesse,

Why do you say yours is messed up?

Bill

 

[Mike SJ]

Jesse, actually if the engineer wanted it to, the LFE on DVD-A can be as full range as your mains. So you might be listening on DD instead and not getting that track cause DD thinks its too high? [speculation speculation]

 

[ScottCHI]

what are your player's bass management settings? try setting all the speakers to SMALL.

 

[Arthur S]

Chu

You seem to have a good understanding of push-pull setups. I've been trying to find out how I would have to set up 2 HSU 1220's in the push-pull arrangement. My guess is that the ends of the tubes with the driver would be brought as close as possible facing each other (cone to cone).

Is this correct? Would the woofs be in phase with each other or out of phase with each other.

Tying 2 of these 50 inch tubes together presents placement problems. In your opinion would it be worth it to even try to set up this push-pull arrangement? The HSU is down only 3db at 15Hz and can produce 107 db (using 2 tubes) at 12.5 Hz. However, there is a moderate amount of distortion getting this output. A lot probably is the result of the bass boost equalizer that HSU sells separately or is included in their 500 watt amp.

The push pull arrangement might be worth it given the distortion when pushing the 1220's hard.

All comments will be appreciated.

Thanks

Artie

Thanks