Home » Sponsored » Pi Speakers » 4PI Cabinet plans / question
4PI Cabinet plans / question [message #73067] Thu, 21 June 2012 01:07 Go to next message
thatsnasty is currently offline  thatsnasty
Messages: 12
Registered: June 2012
Location: Niagara Falls
Chancellor
Hey Wayne, I was wondering if you could send me the cabinet plans?
Smile

I have a couple quick questions in regards to assembling them as well.

Do the plans include a terminal cut-outs? Should the terminals just be standard red/black if not? ( I won't be bi-amping )

Will the $125 pre-assembled x-over work fine with the 2226h? I assume you can upgrade components as well if needed.

Reason being is I just got 2x 2226's from the bay at a good price. They were both pulled from matching cabinets as well so they look to be legit / original cones.

I'm in the same boat about the CD as well. The other AVS'er posted about the Denovo-360 being a good replacement, so I'll most likely get that as well.

Edit: one more thing. If I build a 4pi center, can I build it sealed and ignore the port (similar to the other build thread in the listening room) and not have to worry? I figured since the 2226h works good sealed I'd only be sacrificing bass extension.

Cheers.
Re: 4PI Cabinet plans / question [message #73069 is a reply to message #73067] Thu, 21 June 2012 09:32 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18676
Registered: January 2001
Illuminati (33rd Degree)

I've sent plans to your email address.

Kits include the binding post terminal, but crossovers by themselves do not. The one we ship in the kits need a 2-1/8" x 2-7/8" hole cutout.

The four π speaker and its crossover are specifically designed for the JBL 2226H. You'll want to buy our H290C waveguide, because the crossover was designed for that as well.

For a center channel, you can simply omit the port, if you wish. I would leave the left and right mains vented, as designed. Also use flanking subs to smooth room modes and the self-interference anomalies from floor bounce and the reflection off the wall behind the speakers.

Re: 4PI Cabinet plans / question [message #73070 is a reply to message #73069] Thu, 21 June 2012 10:18 Go to previous messageGo to next message
zheka is currently offline  zheka
Messages: 80
Registered: June 2012
Location: Chicago burbs
Viscount

Wayne Parham wrote on Thu, 21 June 2012 09:32
For a center channel, you can simply omit the port, if you wish. I would leave the left and right mains vented, as designed. Also use flanking subs to smooth room modes and the self-interference anomalies from floor bounce and the reflection off the wall behind the speakers.

what is the down side of doing sealed versions of 4PIs other than higher LF roll-off point? why do you not recommend going sealed for the L/R speakers?

It is often said that sealed mains are easier to integrate in multisub setups when mains and subs overlap. Do you think it is a valid point of view?

Thank you
Re: 4PI Cabinet plans / question [message #73072 is a reply to message #73070] Thu, 21 June 2012 11:07 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18676
Registered: January 2001
Illuminati (33rd Degree)

I do not think it is valid to consider sealed mains to be easier to integrate with multisubs. In fact, I'd say this presumption goes against the whole multisub concept, which is to blend sound sources having various phase relationships and physical locations in the modal region.

The additional extension from vented mains helps increase overlap between mains and flanking subs. The venting also reduces excursion. It is a good thing, all the way around.

I'd rather the center be vented too, but I don't think we lose much to have one channel sealed. It has a different phase characteristic, but then again, being in a different location is sort of the same thing, and is even better. It's the various locations that matter the most.

Re: 4PI Cabinet plans / question [message #73074 is a reply to message #73072] Thu, 21 June 2012 11:09 Go to previous messageGo to next message
zheka is currently offline  zheka
Messages: 80
Registered: June 2012
Location: Chicago burbs
Viscount
very interesting.
thank you!
Re: 4PI Cabinet plans / question [message #73082 is a reply to message #73069] Thu, 21 June 2012 13:34 Go to previous messageGo to next message
thatsnasty is currently offline  thatsnasty
Messages: 12
Registered: June 2012
Location: Niagara Falls
Chancellor

Wayne Parham wrote on Thu, 21 June 2012 09:32
I've sent plans to your email address.

Kits include the binding post terminal, but crossovers by themselves do not. The one we ship in the kits need a 2-1/8" x 2-7/8" hole cutout.

The four π speaker and its crossover are specifically designed for the JBL 2226H. You'll want to buy our H290C waveguide, because the crossover was designed for that as well.

For a center channel, you can simply omit the port, if you wish. I would leave the left and right mains vented, as designed. Also use flanking subs to smooth room modes and the self-interference anomalies from floor bounce and the reflection off the wall behind the speakers.

Thanks for the quick response!

Sealed center seems like a good idea then. It will keep the speakers looking "even" as opposed to offsetting the port either way in the center.

I asked about the terminals because it'll likely cost more for shipping 3 terminals to Canada from PE then it would to get them when I buy the x-overs. Is it possible that I can buy 3 from you, without the kit, and get them shipped with the x/o?

Thanks again, if anything else comes up that the search function cannot find, I'll be sure to bug you Cool
Re: 4PI Cabinet plans / question [message #74826 is a reply to message #73072] Sun, 09 December 2012 10:04 Go to previous messageGo to next message
zheka is currently offline  zheka
Messages: 80
Registered: June 2012
Location: Chicago burbs
Viscount
Wayne Parham wrote on Thu, 21 June 2012 11:07

I do not think it is valid to consider sealed mains to be easier to integrate with multisubs. In fact, I'd say this presumption goes against the whole multisub concept, which is to blend sound sources having various phase relationships and physical locations in the modal region.

The additional extension from vented mains helps increase overlap between mains and flanking subs. The venting also reduces excursion. It is a good thing, all the way around.

I'd rather the center be vented too, but I don't think we lose much to have one channel sealed. It has a different phase characteristic, but then again, being in a different location is sort of the same thing, and is even better. It's the various locations that matter the most.




Is there any reason why the same logic cannot be extended to tapped horn subs? In other words, can THs be mixed with sealed and bass-reflex subs in multisub setups?
Re: 4PI Cabinet plans / question [message #74832 is a reply to message #74826] Sun, 09 December 2012 12:48 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18676
Registered: January 2001
Illuminati (33rd Degree)

Tapped horns, front-loaded hornsubs, bandpass boxes and front-loaded direct radiators - All can be mixed in home hifi and home theater environments. It will help spread out the modes.

This is a big no-no in prosound environments through. The path length differences between horns and direct radiators make integration difficult. Even if you match them with delay, this really only matches them at one frequency because the acoustic center shifts through the passband. So when outdoors or in a large space - where you want point source summing - use only one type of subwoofer.

Re: 4PI Cabinet plans / question [message #74834 is a reply to message #74832] Sun, 09 December 2012 13:09 Go to previous messageGo to next message
zheka is currently offline  zheka
Messages: 80
Registered: June 2012
Location: Chicago burbs
Viscount
Excellent. Thank you.
Re: 4PI Cabinet plans / question [message #75035 is a reply to message #73067] Sat, 22 December 2012 02:39 Go to previous messageGo to previous message
thatsnasty is currently offline  thatsnasty
Messages: 12
Registered: June 2012
Location: Niagara Falls
Chancellor
Hey Wayne, just following up on this thread.
I have my 4Pi's built and they sound fantastic!
The center is sealed as I was talking about above, but I had a question.

I'm currently crossing over the center at 80hz and the L/R at 50hz. I originally had the center at 50hz as well, but during more bass heavy content, I saw it was seeing some pretty decent excursion.

I was wondering if you had an idea how much power the 2226H can take with a 50hz cross in a sealed box?
My receiver (pioneer vsx-1018) will put out around 100-150w at max so just making sure I don't blow the thing up, lol.

Cheers.
Previous Topic: 4pi Crossover Questions
Next Topic: Value of L1 on 7Pi schematic?
Goto Forum:
  


Current Time: Fri Apr 19 18:55:20 CDT 2024

Sponsoring Organizations

DIY Audio Projects
DIY Audio Projects
OddWatt Audio
OddWatt Audio
Pi Speakers
Pi Speakers
Prosound Shootout
Prosound Shootout
Smith & Larson Audio
Smith & Larson Audio
Tubes For Amps
TubesForAmps.com

Lone Star Audiofest