Flex Your PCD Mettle:

[Zilch]

Re: EconoWave 4x

As an early adopter of the economical D95HF-1 PT waveguide, I liked its potential, but did not have the skills to tweak the E-Wave circuit sufficiently. Thanks for doing this.

PCD is TRICK!

Is the woofer on the left an Eminence?

JBL 228H:

http://www.jblproservice.com/pdf/AE%20Series%20Compact%20Models/AC1895-WH.pdf

[Another variant.... :rolleyes: ]

[Skywave-Rider]

Re: EconoWave 4x

Oh yes. I remember.
Hard to keep all your variants in buffer memory.
Unobtanium woofers?

PCD is still gonna happen here.

PCD is TRICK!


JBL 228H:

http://www.jblproservice.com/pdf/AE%20Series%20Compact%20Models/AC1895-WH.pdf

[Another variant.... :rolleyes: ]

[Zilch]

Re: EconoWave 4x

Unobtanium woofers?

Worthy pursuits: copper-clad aluminum voice coil, SFG motor, copper-clad vented pole piece. Pro Parts can't sell these direct, but authorized JBL Pro dealers and service centers can get them.

http://www.jblpro.com/catalog/support/getfile.aspx?doctype=3&docid=1080

Not terribly expensive, as I recall, $118.

[Biggest magnet I've ever seen on an 8".... ]

[darrellh44]

Re: Flex Your PCD Mettle:

At the risk of sounding like a complete blithering idiot, what the heck does PCD stand for? I hate TLAs.

Thanks,
Darrell

[Flacjunky]

Re: Flex Your PCD Mettle:

At the risk of sounding like a complete blithering idiot, what the heck does PCD stand for? I hate TLAs.

Thanks,
Darrell

PCD = Passive Crossover Design

[Zilch]

Re: Flex Your PCD Mettle:

http://techtalk.parts-express.com/showthread.php?t=217994

[Skywave-Rider]

Re: Flex Your PCD Mettle:

No ladder delays in PCD. Who can really complain about its feature set considering the price?

[Zilch]

Flex It Round #5.0 - Econowave SR

The new Dayton Pro 12" PA310-8 rear-mounted in Dayton KD Trapezoid cab with bolt-on Selenium D220Ti-OMF-8 compression driver on QSC 152i waveguide:




Raw driver responses:




First attempt in PCD7:




The measured response:




Four hours less dinner from raw driver measurements to actual proto crossover response within 1 Hz XO frequency at max inverse null.

[PCD rocks and RULEZ...! ;) ]

[Zilch]

Re: Flex Your PCD Mettle:

As with most higher-efficiency pro woofers, these need subs. In this 1.65 cuft. ported alignment tuned to ~35 Hz, a 6 dB Q=2 assist at 45 Hz coaxes them to play 40 Hz, but not commandingly.

Measured at 44" mic distance on axis midway between woofer and waveguide centers, the pair being 10" apart. Woofer piston diameter 10", waveguide throat entry 1". FRD files include minimum phase, HF driver with L-pad set at 1:00....

The files for PCD:

[Pete Schumacher]

Re: Flex It Round #5.0 - Econowave SR

The new Dayton Pro 12" PA310-8 rear-mounted in Dayton KD Trapezoid cab with bolt-on Selenium D220Ti-OMF-8 compression driver on QSC 152i waveguide:




Raw driver responses:




First attempt in PCD7:




The measured response:




Four hours less dinner from raw driver measurements to actual proto crossover response within 1 Hz XO frequency at max inverse null.

[PCD rocks and RULEZ...! ;) ]

Looks excellent Zilch. What's to improve upon? :D

[Zilch]

Re: Flex It Round #5.0 - Econowave SR

Looks excellent Zilch. What's to improve upon? :D

I coulda used shorter screws, maybe.

That's one heavy beast of a magnet on the PA310, after working with the Eminence neodymiums. :p

Looks like giving up a couple of dB with a low-Q broadband notch at 400 - 900 Hz wouldn't hurt.

[Dunno, you've surprised us with "refinements" before here.... ;) ]

[Pete Schumacher]

Re: Flex It Round #5.0 - Econowave SR

I coulda used shorter screws, maybe.

That's one heavy beast of a magnet on the PA310, after working with the Eminence neodymiums. :p

Looks like giving up a couple of dB with a low-Q broadband notch at 4 - 9 kHz wouldn't hurt.

[Dunno, you've surprised us with "refinements" before here.... ;) ]

Well, if you want to get really nit picky . . .

A broadband notch from 400 to 800 would be helpful too.

I'll play around with the files and see what kind of complicated XO I can come up with . . . ;)

[Zilch]

Re: Flex It Round #5.0 - Econowave SR

A broadband notch from 400 to 800 would be helpful too.

Yah, that, instead.

[It slipped a decade.... :o ]

[Pete Schumacher]

Re: Flex Your PCD Mettle:

OK, two notches!!!

Tweeter polarity is positive along with the woofer. For the woofer notch, .7mH 20ga and 3 Ohm instead of the slightly off values shown will work. Ignore the woofer name. I'll update that later.

[Skywave-Rider]

Re: Flex Your PCD Mettle:

You guys are an amazing team.
Looking on, entertained and floored.