Hook up both coils for my IB? (1 Viewer)

[Lee Weiss]

I am in the middle of my IB install in my attic. I have one Dayton DVC 12" (so far) and a PE 250w amp. I have read that when running two drivers, only one voice coil for each should be used, and wired in parallel.
What do you do when you have only one driver? I assume I want to it at 4ohm.
What are the benefits of one/both?
I also want find out how I can add a couple of extra hours in a day.

 

[Brian Bunge]

Lee,

With two drivers and the PE 250w amp you'd wire the voice coils on each driver in series and then parallel the two drivers to get an 8 ohm load. With the single driver simply wire the voice coils in parallel for a 4 ohm load with your amp.

If you figure out how to add a few hours to a day let me know!

Brian

 

[ThomasW]

Lee
Wire the VC's in parallel.
Also take some pics of the install and I'll put them on the Link Removed

 

[Rick Guynn]

Lee, from what I understand, the reason for wiring it as you have described is to 'adjust' the Qts of the driver. Using only one coil on the driver effectively doubles the Qts from ~.38 (very underdamped, I think) to ~.76 (nicer neighborhood).

This value can actually be 'dialed in' on DVC drivers by putting a resistor of appropriate value across the unused coil. You might go look at the white paper for resistively damped operation (RDO) over on the Adire site.

Rick

 

[Lee Weiss]

Rick,

Will check into it. Thanks for the responses. I still have to get a book and spend some time learning.

*** EDIT ***

Just read the Adire site about wiring the DVC. It seems like the "right" thing to do would be to figure out the RDO math and what end result I want, and get a resistor.

Using Adire's spreadsheet, a 250ohm resistor would give a Qts of .70. Should be good for HT.

Call me a geek, but this is fun!

Tom,

I will take some pics, but I am afraid my setup would look a bit lame next to the others on the site. If I do like planned and recess the amp in the wall or come up with another scenario, I will post pics.

 

[ThomasW]

Lee
It's not a competition
I'd like the gallery to showcase a wide selection of different installs/designs.

 

[Lee Weiss]

It is more a disease that I, as many do, suffer from.

Will do on the pics, and this will be more incentive to make things tidy.

 

[Lee Weiss]

I am confused on one thing regarding RDO. If I cannot pick up the POT that I need, should I just short the second coil, or leave it open?

I understand that with a POT, I can nearly double the Qts, to get what I want, but will running just one coil and leaving the other open, be way underdamped?

I tested out the amp and manifold before I mounted it up in the attic, and it vibrated the floor, but did not sound that great. I am assuming that is because of lack of separation of front and back waves.

Two weeks of vacation starts today, time to make sawdust.

 

[Jack Gilvey]

I am confused on one thing regarding RDO. If I cannot pick up the POT that I need, should I just short the second coil, or leave it open?

I understand that with a POT, I can nearly double the Qts, to get what I want, but will running just one coil and leaving the other open, be way underdamped?

Leaving it open will result in a Qtc of ~.8, technically "underdamped" (although when Mike Knapp heard Rich Kraus' this way, he called it the best bass he'd heard). There would be no point in shorting it if using just one driver, I would just run in parallel for a Qtc of ~.4, technically overdamped.

Using resistors, or a potentiometer (variable resistance), will allow you to pick anything in between. If I recall correctly, I used 6.3ohm resistors on my Tempests for a Qtc of ~.5.