Home » Sponsored » Pi Speakers » What's going on in Pi world, eh?
What's going on in Pi world, eh? [message #39382] Sat, 07 December 2002 12:43 Go to next message
mikebake is currently offline  mikebake
Messages: 243
Registered: May 2009
Grand Master
Who's got something cooking?

Till, update The Great Flood, eh?

I have yet to take delivery on the 2245H subs, Dale says he is thinking of delivering them tmrw. Good, the wife won't be home and I can sneak the monsters into the shop. They have wheels on them.
"oh, THOSE? I've had those a LONG time"
My buddies will be back for Xmas for a few days, so naturally I have to have them working by then.
MBB

Re: What's going on in Pi world, eh? [message #39383 is a reply to message #39382] Sat, 07 December 2002 16:40 Go to previous messageGo to next message
Wayne Parham is currently online  Wayne Parham
Messages: 18678
Registered: January 2001
Illuminati (33rd Degree)
I've been making a model of an active crossover that implements the same EQ as the passive π crossover. So I've been keeping pretty busy lately.

Active implementation of π compensated crossover using 6DJ8 tube

I'm modeling this circuit using PSpice.

Re: What's going on in Pi world, eh? [message #39385 is a reply to message #39383] Sat, 07 December 2002 20:19 Go to previous messageGo to next message
replay is currently offline  replay
Messages: 284
Registered: May 2009
Grand Master
hi wayne, the x-over is exciting. are you using a 24db/octave slope?. also will the x-over be adjustable? tubes sound cool. are you going to sell in kit or finished form? what's the anticipated retail. i don't mind being a guinea pig and testing your first sample.

cheers,

george
12awg concealed in garden hose and priced at $50 ft sounds best. really!!

Re: What's going on in Pi world, eh? [message #39386 is a reply to message #39385] Sat, 07 December 2002 20:42 Go to previous messageGo to next message
Wayne Parham is currently online  Wayne Parham
Messages: 18678
Registered: January 2001
Illuminati (33rd Degree)
I've based my work on that of Steve Bench because he has extensive hands-on experience with tubes and tube designs. I am designing the filters that precede the 6DJ8 and that's really all there is to the circuit. It's two sections of a 6DJ8 tube, so two tubes are needed for stereo, and then the filter and that's basically it. There's a coupling cap on both sides, which is then really an additional VLF high-pass filter, and then there's the crossover filter and compensation circuit. It's so simple, it almost has the same low parts count of the passive crossover.

The slope for each section can be made first, second or third order and the crossover point is selectable. But that's done by picking components, not by placing jumpers, or setting switches or potentiometers. One of the things that prompted the choice to use an existing design is that there is a circuit board already available which has plate-through holes for additional parts - Hopefully enough for the components needed for the π compensation circuit. I've discussed this matter with Steve, and he believes that this can be accomplished without "hacking" the circuit board.

I've always hated etch cuts, jumpers and "floating" components, but it's attractive to be able to use an existing board as long as a lot of etch modifications aren't required. If extensive cuts are required and I then I may decide to have board etched instead. We'll see how much response there is.

Pant! Pant! [message #39387 is a reply to message #39386] Sun, 08 December 2002 05:11 Go to previous messageGo to next message
Garland is currently offline  Garland
Messages: 269
Registered: May 2009
Grand Master
"Dear Santa" may be "Dear Easter Bunny"! I can wait , but barely!

G

Re: What's going on in Pi world, eh? [message #39388 is a reply to message #39386] Sun, 08 December 2002 06:53 Go to previous messageGo to next message
billfort is currently offline  billfort
Messages: 34
Registered: May 2009
Baron
Hey Wayne - this is exciting stuff! This is exactly what I've been looking for for my Altec 604's. Tube crossover, 12db slopes, compensation for horn. I'm building another 300B SET amp to go with the one I already use, in anticipation of something like this. Can't wait! Keep up posted.

Billf

i am also waiting for a change like this, [message #39389 is a reply to message #39383] Sun, 08 December 2002 07:01 Go to previous messageGo to next message
Zeno is currently offline  Zeno
Messages: 122
Registered: May 2009
Master
when will be the ist review
Re: What's going on in Pi world, eh? [message #39391 is a reply to message #39386] Sun, 08 December 2002 12:40 Go to previous messageGo to next message
DRC is currently offline  DRC
Messages: 169
Registered: May 2009
Master
Oh man! This is just what I'd want for the TAD/JBL/TAD monsters. Not in love with the DBX active I'm using, and would rather not do the passive with this in the wings . . . ..

How long, oh how long . . . . I'll happily volunteer to be a guinea pig on this baby!


Keep your ears and your mind open.

Re: What's going on in Pi world, eh? [message #39393 is a reply to message #39383] Sun, 08 December 2002 14:36 Go to previous messageGo to next message
BillEpstein is currently offline  BillEpstein
Messages: 886
Registered: May 2009
Illuminati (2nd Degree)
Soon I'll have Paramours on top and Ella on the bottom and I'll need some "resistors lying on the beach" type help with the hook-up.
And I'll probably take the Goldpoint's out of the Foreplay and build a 'badass passive' with'm for the 2 amps. I'll need 2 "outs" tho, won't I? May as well put in a selector switch then, too.
I think I'll change the name of my website to: No User Serviceable Parts Inside.com.
Till, check out the Love Kitten in the current "Valve"(nt) [message #39394 is a reply to message #39393] Sun, 08 December 2002 15:18 Go to previous messageGo to previous message
Garland is currently offline  Garland
Messages: 269
Registered: May 2009
Grand Master
...and now is the time to get a pair of cobalt B7 linestage trannies from Mikey!

G.

Previous Topic: An Inadvertent Christmas Present?
Next Topic: Stomberg Carlson really cool tube amp on 4-pi pro/Altec
Goto Forum:
  


Current Time: Fri Apr 26 16:24:56 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