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Driver Escalation [message #38799] Wed, 23 October 2002 12:22 Go to next message
DRC is currently offline  DRC
Messages: 169
Registered: May 2009
Master
Wayne,

Did you ever sell the TAD 1602's you were parting out over the summer? If not, I'll take 'em!

I must have read 500 posts today on Hi Eff and Pi, and finally fell over your discussion of using these babies in a 4PiBR Pro 3.5 ft3 box, as well as the fact that you had a pair (at some point) to sell.

I'd put the cabs on 11" mass-loaded stands, with Bill Martinelli's horns and Eminence PS 2002's on top of them, using your 800hz (??) xover. I'd upgrade the 2002's when I recover from the shock of the initial outlay!

I would expect this combo to be quicker, lower distortion, sweeter, albeit less efficient than the Theater 4's. Does that make sense? I'm after horn speed and effortlessness used with SET's, not ultimate SPL's.

Thanks!
Keep your ears and your mind open.

Re: Driver Escalation [message #38800 is a reply to message #38799] Wed, 23 October 2002 13:18 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18677
Registered: January 2001
Illuminati (33rd Degree)
I've still have the TAD 1602 drivers, so if you want them, E-mail me and we'll make arrangements. PiAlign recommends a 3.85 ft3 motor chamber tuned to 37.5Hz with a 4.65" dia. x 4.4" long port, or a rectangular port that's 3.1" x 5.5" height and width and 4.4" long. They're perfect for a three-way cornerhorn, like the ones I've made with a 2123 midrange driver.
Re: Driver Escalation [message #38801 is a reply to message #38800] Wed, 23 October 2002 13:26 Go to previous messageGo to next message
DRC is currently offline  DRC
Messages: 169
Registered: May 2009
Master
Excellent!

Drop me a line, offline if you like, as to the total including shipping to 06033, and how I can make payment. I'm rarin' to get started, now!

Hmmmm . . . What driver will suit Bill's horns and play nicely with the 1602's in a two way system? 2426's? TD2001's (Gulp!) I really don't want to turn this into a 3-way circus if I can help it.
Keep your ears and your mind open.

Re: Driver Escalation [message #38802 is a reply to message #38801] Wed, 23 October 2002 13:30 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18677
Registered: January 2001
Illuminati (33rd Degree)
The TAD 1602 sounds nice down low but you'll want to crossover lower than I would be comfortable with a 1" exit driver. You might consider pairing it with a TAD 4001 2" exit compression driver. Most 2" exit drivers don't reach the top octave but the beryllium diaphragm in the 4001 makes it sound nice all the way up.
PSD2002 [message #38803 is a reply to message #38800] Wed, 23 October 2002 15:14 Go to previous messageGo to next message
LuxmanLover is currently offline  LuxmanLover
Messages: 164
Registered: May 2009
Master
Could the PSD2002 get down to 1100Hz if power levels were kept low?
Kelly
Re: PSD2002 [message #38805 is a reply to message #38803] Wed, 23 October 2002 16:04 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18677
Registered: January 2001
Illuminati (33rd Degree)
Certainly, it could be used at lower frequencies if diaphragm movement was limited by use of less power. In this de-rated mode of operation, maximum SPL and dynamic range are reduced. Alternatively, you might use a high slope HP filter in the crossover, to help reduce out of band LF energy and thereby reduce excursion.
Re: PSD2002 [message #38806 is a reply to message #38805] Wed, 23 October 2002 16:34 Go to previous messageGo to next message
DRC is currently offline  DRC
Messages: 169
Registered: May 2009
Master
Okay, so if the 2002 is rated at 80w at a min of 1.5k, it would be good for 20w or so at 750hz, and presumably more than that at 1200. Bill's Classic horn is nominally 800, so crossing it over at 1200 using amps that won't be bigger than 8w/ch shouldn't pose a threat. May not be ideal, but won't get cooked, either.

TAD quotes the 1602's range as 21hz-2k, crossing over nearly an octave lower - 1,200hz ought to be okay, shouldn't it. Again, maybe not ideal . . .

I would expect the 2426 or TD-2001 to work better, and allow the 1602 more breathing room, since they are spec'd as having usable ranges of 500hz -20khz+.

I'm not being argumentative, just trying to learn here, guys.

Thanks for the input!


Keep your ears and your mind open.

Re: PSD2002 [message #38807 is a reply to message #38806] Wed, 23 October 2002 16:55 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18677
Registered: January 2001
Illuminati (33rd Degree)
I think your reasoning is sound. All two-way speakers of this scale are pushing each subsystem to its limits, and the idea is to get two parts that are the best you can get. Sound like that's exactly the direction you're going, so let us know how your speakers turn out!
Cabinet considerations for TAD 1602's [message #38809 is a reply to message #38800] Thu, 24 October 2002 08:33 Go to previous messageGo to next message
DRC is currently offline  DRC
Messages: 169
Registered: May 2009
Master
Wayne,

You've got mail! ;-)

You wrote:
>That's right. PiAlign recommends a 3.85 ft3 motor chamber tuned to 37.5Hz
>with a 4.65" dia. x 4.4" long port, or a rectangular port that's 3.1" x 5.5" height
>and width and 4.4" long.

Okay, 3.85 is a touch bigger than the Pi4 Pro, but that's considering external dimensions, as if the walls had no thickness, and the 1602 occupied no space at all. Hmmmm . . . How do I ramp up the externals to get 3.85 internal using 3/4 stock with a doubled baffle?

In terms of proportions, I'd like to have 29"-30" height and 17" width to get Bill's horns to the right height for seated listening (spkrs on short stands), and match the horn width.

If I take the Pi4 Pro cab, and arbitrarily bump each dimension up .75" for illustrative purposes, I'd have 26.75"x18.75"x14.75" or about 7,400 in3 or 4.3 ft3 externally. Reshaping this, maintaining the volume, I'd have 30"hx17"wx14.5d.

I'll want to hit the volume more precisely, which will change the dimensions, but will those sort of proportions keep me out of trouble? Is the height too close to being an even multiple of the depth?

This is getting exciting - Diverse drivers rolling along in brown trucks all over the country . . ! ;-)
Keep your ears and your mind open.

Re: Cabinet considerations for TAD 1602's [message #38810 is a reply to message #38809] Thu, 24 October 2002 11:12 Go to previous messageGo to previous message
Wayne Parham is currently offline  Wayne Parham
Messages: 18677
Registered: January 2001
Illuminati (33rd Degree)
A good enclosure size for the TAD 1602's is 30" x 20" x 14.5", using 1" stock and a rectangular port that's 3.1" x 5.5" and 4.4" long. That would look very good with Bill's horns too. You could reduce the width to 17" and increase the depth and/or height a little too, if desired, matching the width of the cabinet to the width of the horn.
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