After a day's work on the computer...

[tomzarbo]

...this is what I have to show for it.



I'm so bleary-eyed, I can't see straight, but at least it's a start.

I really can't imagine how many hours you guys who know what you're doing must've spend learning this stuff; it boggles my mind.

I'm not really even sure what I've done here; I know there's a bunch of stuff wrong with this. I worked a little, watched some tutorial videos, worked a little more...
I'll revisit it in a few days and see if it makes any more sense to me. Did this in WinPCD BTW.
Please don't ask to see the phase graphs, the lines in those look like someone dropped a rock on a pane of glass.

I'm happy I finally got my feet wet with this 'cause I really want to bring my own creation to the 2014 MAF but dang, my head hurts. :o

TomZ

[donradick]

Re: After a day's work on the computer...

I feel your pain! Been there, done that, gonna do it some more, call it a fun hobby.....
At least the little squiggly lines look good.

[Ryan_M]

Re: After a day's work on the computer...

FR looks great, I'd still like to see those phase graphs though. Come back to the designs from time to time and tinker. It'll start to get a more intuitive as to what results changes will have. BTW what drivers are you using?

[lowpolyjoe]

Re: After a day's work on the computer...

Congrats. I just started playing with PCD myself. Lots to learn. You're a lot further along than me . Good luck.

[relder]

Re: After a day's work on the computer...

I worked a little, watched some tutorial videos, worked a little more...

Which videos did you find helpful?

[tomzarbo]

Re: After a day's work on the computer...

I feel your pain! Been there, done that, gonna do it some more, call it a fun hobby.....
At least the little squiggly lines look good.

Pain is a good word to use. After dinner and a little break I feel a bit better, at least I don't want to throw my laptop out of the window anymore.

FR looks great, I'd still like to see those phase graphs though. Come back to the designs from time to time and tinker. It'll start to get a more intuitive as to what results changes will have. BTW what drivers are you using?

Wise guy, huh? I'm tinkering with the DS drivers, an 8" and two passives for the bass line and the 5" for a mid, and for now a ND20 tweeter until I can get FRD and ZMA files for the ND28F-6 which I haven't been able to locate yet. I think it's incredible how when you make changes in the value fields of the crossover components, the graph changes instantly. A lot better than X-Over Pro I'll tell you.

Well, you asked for it: :eek:

Congrats. I just started playing with PCD myself. Lots to learn. You're a lot further along than me . Good luck.

It seems to be an amazingly powerful program, doesn't it? It will take a knucklehead like me a bit of time to get this down, but we start with baby steps, right? Keep at it joe, I will as well. I was fortunate to have a snow day today from school so I had a lot of hours right in a row to immerse myself in it. It's hard for me to gather much momentum with just an hour or so to work with it.

Which videos did you find helpful?

Johnny Richards made a very good video of PCD. Here is the link: https://www.dropbox.com/s/v73tkc8byw...titled%208.avi
He posted about it on this thread: http://techtalk.parts-express.com/sh...ghlight=videos

I've watched it a bunch of times and every time a little bit more sinks in; but really, I have to just start playing with it as much as I can to get familiar with it. I've also been reading and re-reading Speaker Building 201 by Ray Alden, it covers basic concepts very well... I just ignore the troublesome math portions.

Also Dave (DLR) has some videos of WinPCD up on the Meniscus site under 'video lessons.'
http://www.speakerdesign.net/WinPCD/index.htm

[rpb]

Re: After a day's work on the computer...

Just a WAG, but try a smaller value coil, and a larger value cap on the mid lowpass to raise the output of the mid in the 2k to 3k range, and create a sharper knee in the rolloff. I'd probably lower the mid / woofer x-over point to 400 hz too, but what you have there looks good.

[Pete Schumacher]

Re: After a day's work on the computer...

I'd spend a little more time on the mid/tweet XO. You've got a summation that undercuts the tweeter response which means your phase tracking is a bit off. Try a bit steeper slope on the mid.

[LITTLEME60]

Re: After a day's work on the computer...

i'll get there some day.

[tomzarbo]

Re: After a day's work on the computer...

Forgot to mention that the mid and tweeter are rev. polarity.
Thanks for the ideas rpb and Pete. I'll fiddle some more.

TomZ

[Pete Basel]

Re: After a day's work on the computer...

I like what you're doing, a 3-way is challenging and you'll learn a lot.

I suggest that you think more about your crossover points and go bigger
on the woofer since you might as well have the output and extension if
you are going to pay for the extra cost in a 3-way. A 3-way provides the
option of using a true midrange with minimal breakup in the operating
range unlike mid woofers that are just small woofers.
If your intention is to have in-phase crossovers then they will be -6 dB at
the crossover. Your woofer is so high and tweeter so shallow that they are
both contributing a good amount at about 1.5 -2K and therefore you never
need the full output from the midrange.
Did you have a particular layout or another system in mind that you'd like
to model the design after?
I like the PSB Stratus Golds, might give you some ideas:
http://www.stereophile.com/floorloudspeakers/704

[[email protected]]

Re: After a day's work on the computer...

with pcd Ill get the files loaded and offsets entered and then save it. Reload the file and go nuts. If it all goes to hell, Ill reload the saved file and try again. maybe Third order instead of 2nd. maybe the padding before the crossover instead of after. maybe split for and aft. at this point you just want to play until you have some ah-ha moments. when it goes to hell, clear it out and reload the saved file and try some more. don't over think it. Don't decide before hand where the xovers have to be.. let the drivers talk to you.

[Wolf]

Re: After a day's work on the computer...

with pcd Ill get the files loaded and offsets entered and then save it. Reload the file and go nuts. If it all goes to hell, Ill reload the saved file and try again. maybe Third order instead of 2nd. maybe the padding before the crossover instead of after. maybe split for and aft. at this point you just want to play until you have some ah-ha moments. when it goes to hell, clear it out and reload the saved file and try some more. don't over think it. Don't decide before hand where the xovers have to be.. let the drivers talk to you.

Good advice that is.
Darn- I sound like Yoda....
Wolf

[mattk]

Re: After a day's work on the computer...

The biggest question with any three way is what does your impedance look like?

[tomzarbo]

Re: After a day's work on the computer...

I like what you're doing, a 3-way is challenging and you'll learn a lot.

I suggest that you think more about your crossover points and go bigger
on the woofer since you might as well have the output and extension if
you are going to pay for the extra cost in a 3-way. A 3-way provides the
option of using a true midrange with minimal breakup in the operating
range unlike mid woofers that are just small woofers.
If your intention is to have in-phase crossovers then they will be -6 dB at
the crossover. Your woofer is so high and tweeter so shallow that they are
both contributing a good amount at about 1.5 -2K and therefore you never
need the full output from the midrange.
Did you have a particular layout or another system in mind that you'd like
to model the design after?
I like the PSB Stratus Golds, might give you some ideas:
http://www.stereophile.com/floorloudspeakers/704

Pete, by "bigger" on the woofer, do you mean larger size, or larger (higher) crossover point? This alignment should reach almost 101 db at 30 Hz while barely breaching X-Max, while keeping a specific 'aesthetic' that I'm going for in this particular design. I sort of already have a vision of what I would roughly like this design to look like, so I'm trying to keep within that 'look' if possible.

I see what you mean about the midrange situation. I think some of my problem is that I'm trying to 'tweak' this too much to make up for the fact that the mid is several db less efficient than the woofer, and I know I should not pad the woofer. I will look at a few dedicated mid-range drivers to see if they are a better match. Trouble is finding the files for some of these things. Thanks for the link to the PSB Stratus Gold speakers, I read the info, but I'll look it over more later.

with pcd Ill get the files loaded and offsets entered and then save it. Reload the file and go nuts. If it all goes to hell, Ill reload the saved file and try again. maybe Third order instead of 2nd. maybe the padding before the crossover instead of after. maybe split for and aft. at this point you just want to play until you have some ah-ha moments. when it goes to hell, clear it out and reload the saved file and try some more. don't over think it. Don't decide before hand where the xovers have to be.. let the drivers talk to you.

Good advice that is.
Darn- I sound like Yoda....
Wolf

Thanks for that tip. That will save me a bunch of time and trouble. Let the drivers talk to you, got it. I can see this process being an awful lot of fun once you know how things work.

Thankful, I am.

The biggest question with any three way is what does your impedance look like?

I'll try to post that up tonight, but I've changed things since I posted the above, so...

Thanks everyone,
TomZ