Announcement

Collapse
No announcement yet.

Flex Your PCD Mettle:

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Re: Flex Your PCD Mettle:

    Originally posted by tmhutson View Post
    I am planning on buying new woofers to go with my seos12/CD and a matching crossover to have the best sound I can afford and for the type of sound I want.

    Until that time, I am playing around with some Cerwin Vega woofers to see if I can learn how to use PCD7 and some of the more technical side of passive crossover design.
    I have gotten to a point where I am about to start entering data into PCD7 and am looking for willing participants to help me learn to enter the parameters on PCD7 as I see it on a crossover schematic. I am still new to crossover design and have reach a point where I need more help.

    I am using a generic econowave crossover, and not sure how to enter the values into pcd as I see them on a diagram/schematic. I have other designs I want to try out while also learning to play around with other options. I can't do that until I more knowledgeable on PCD.
    I have opened frd files for woofer and tweeter, and played a little bit with basic crossover points. But I don't know the more complex stuff like notch filters and what not.
    Even if I saw a schematic for a filter, I don't know how to enter it into PCD.

    I have been reading papers and what not by Wayne Parham and others that have direct experience with compression drivers. Some of the speak is a little too technical for me, but have still learned a lot from the info.

    I guess I just need help with applying information on PCD7 now.
    I read as much as I could find the last couple of days or so specific to compression drivers, and feel I am ready to start diving into PCD7 with some help. I am more of a hands on type learning, and need some computer time on PCD.

    Here is a link to my current project. I can provide ZMA and FRD files if need be.

    http://techtalk.parts-express.com/sh...stalled-SEOS12

    These woofers are only ok compared to a higher quality, high efficiency woofer like the deltalite II 2512 (the CV is similar to a Dayton Classic). But they will help me learn.
    Thanks to anyone who read this. :D
    Todd
    PCD does have a schematic diagram to which you can refer.

    Post a shot of the "generic econowave crossover" and we can post a few screen shots of the way it would look in PCD.
    R = h/(2*pi*m*c) and don't you forget it! || Periodic Table as redrawn by Marshall Freerks and Ignatius Schumacher || King Crimson Radio
    Byzantium Project & Build Thread || MiniByzy Build Thread || 3 x Peerless 850439 HDS 3-way || 8" 2-way - RS28A/B&C8BG51

    95% of Climate Models Agree: The Observations Must be Wrong
    "Gravitational systems are the ashes of prior electrical systems.". - Hannes Alfven, Nobel Laureate, Plasma physicist.

    Comment


    • Re: Flex Your PCD Mettle:

      I found the schematic when I first opened it. I had obligations today so no speaker fun today.
      Thanks for the reply. I am proficient at MS paint, so can show where my stupidity is as far as PCD is concerned... :D

      Comment


      • Re: Flex Your PCD Mettle:

        I use winpcd which is the same as pcd except the fact that that it doesn't run on office and is faster. It actually has a schematic that shows the parts and where they are as you enter them.

        Comment


        • Re: Flex Your PCD Mettle:

          I will download it and look at it later. If it's faster, that is good. I keep getting stupid security warnings every time I open pcd. So annoying. Thanks.

          Comment


          • Re: Flex Your PCD Mettle:

            so, WINPCD is exactly the same but doesn't need Excel to run, and is faster? Wow, I just purchased Office 2007 to install on my machine just so I can run PCD. Luckily I didn't open the package yet
            nikkolur

            Comment


            • Re: Flex Your PCD Mettle:

              Originally posted by nikkoluvr View Post
              so, WINPCD is exactly the same but doesn't need Excel to run, and is faster? Wow, I just purchased Office 2007 to install on my machine just so I can run PCD. Luckily I didn't open the package yet
              nikkolur
              There are a couple minor differences but they work the same as far as how you input the files and enter the xo parts. The main system graph is different in that it is in a seperate window as are the circuit layout and a couple other things. This can get crowded on a smaller screen but I got use to it. If I had a higher resolution on my old laptop this might not be a issue. You should definately try it before spending money on office. Don't forget that there are other tools that use office though.

              Comment


              • Re: Flex Your PCD Mettle:

                I just tried to install WinPCD. My old POS laptop doesn't have enough memory, and I am not in the mood to delete files. I just need a new computer. :D
                My PC is full as well.
                I will stick with PCD7 for now.

                Comment


                • Re: Flex Your PCD Mettle:

                  Overlay is not working. It worked for a bit then stopped. Have closed the program and re-opened it to no avail. Not sure what is going on. PCD's combined did not look perfectly like my measured combined. Close, but not quite. But now the overlay is not working so I don't know how to fix anything.

                  I was looking at the schematic examples. They show zobels, contour filters and notch filters. This helps me a bit.

                  Here is the diagram of the generic filter I am using now.

                  I am hoping that if the measured combined looks the same as PCD's combined, then I can use my measured CERWAVE with crossover to see if PCD's version looks close. But until I figure out the stupid PCD problem, I don't know what to do.

                  I did finally figure out how to ad a simple inline resistor. So I am making headway. Slowly, but surely. I am playing around with different slopes and frequencies just to see effects and learn how things work. Still don't know about phase and what not.
                  Attached Files

                  Comment


                  • Re: Flex Your PCD Mettle:

                    Originally posted by tmhutson View Post
                    . PCD's combined did not look perfectly like my measured combined. Close, but not quite. .

                    .
                    I think you should post this in your other thread as it is easier to go back and see what you have already done as far as how you measured things and set things up ;)

                    Comment


                    • Re: Flex Your PCD Mettle:

                      Originally posted by tmhutson View Post
                      . PCD's combined did not look perfectly like my measured combined. Close, but not quite. .

                      .
                      I think you should post this in your other thread as it is easier to go back and see what you have already done as far as how you measured things and set things up ;)

                      Comment


                      • Re: Flex Your PCD Mettle:

                        I am not sure what is going on here. I entered the LP (C2 L2) onto PCD and now the response of the woofer looks odd. Not right at all. What am I doing wrong?

                        Here is a screen shot of what I entered. When I have PCD calculate the L2 C2 automatically for a second order at 1.2k, I get different results, but close to the econowave. And the calculated still looks off. How can an LP filter increase the response at crossover frequency? I set the filter for 1.2k.
                        The filter has an increase at crossover frequency, which it did not when I was playing around with the woofer with NO zma file attached. Is my ZMA file messing with the crossover?.

                        I got the overlay to work. Just had to redo the frd files again.
                        Attached Files

                        Comment


                        • Re: Flex Your PCD Mettle:

                          I looked over some of the Wayne Parham pdf's about crossovers. I am learning even more.
                          I looked up the schematics on PCD.
                          I am pretty sure I have the hang of entering most stuff now. I was looking at the wrong schematic and the numbers didn't make sense. Now they do.

                          I was able to add a zobel on the woofer to correct the simulation issue where it was peaking at 1.8k.
                          But what I don't understand, is that I don't think it's peaking in my real measurements like it is in the sim.
                          There is no zobel on the econowave crossover, though. I am confused on this.

                          I am having an issue entering the 16 ohm resistor value on the econowave crossover into the R14 slot on PCD. As you can see in the picture, when I click on r14 it already says "16" in the "fx" field. I am not sure why. I had not entered anything. I need to enter the R14 value, as I think it might be a damper.

                          The contour of the tweeter looks all messed up, and the level is a little low. I am getting a little farther, and learning a little more. But still having issues.

                          Screen shot to show what issue I am having with R14...


                          I just looked at my woofer sim with crossover, vs a holmimpulse FR I had for woofer alone with LP crossover. The 1.8k peak is lower on the sim with the zobel. So I think the zobel is working properly in the sim. If I am entering the parameters correctly, and the sim is accurate on the woofer, it may help tone down the resonance at 1.8k a bit. But until I figure out how to enter the econowave HP properly, I won't know how it will work at all. I am getting so close! Dangit...
                          Attached Files

                          Comment


                          • Re: Flex Your PCD Mettle:

                            I think your crossover values are spread far enough apart (best way I can describe it) If you make the capacitor larger or the inductor smaller I think the spike will flatten out. When components get close to affecting the same frequency range (usually when you are trying to get the rolloff really steep) you can get a hump.

                            Comment


                            • Re: Flex Your PCD Mettle:

                              Thanks for the reply, Killa.

                              Right now I am trying to see how close the sim is vs the actual econowave crossover measurement so that I know I am entering the econowave crossover values correctly into PCD. I did play with some values just to see how they would change the sim. A zobel cleaned things up a little. But the crossover schematic I am using does not have a zobel, so am not entering one just yet... I am trying to stay focused here. :D

                              I have attached a pic of the sim'd combined FR that I have so far. It's almost there.
                              The inlay is of the CERWAVES as measured from tweeter axis. I entered the mic measuring distance.
                              The tweeter contour of the sim is not quite right.
                              The only part of the econowave crossover I have not been able to enter into PCD is the 16 ohm resistor. I think I am wrong in assuming that the econowave schematic has the 16 ohm resistor which looks like it correlates to the R14 position. I can't use a leg, as the resistor is in parallel before the countour that is in series.
                              I will include the schematic to see if you understand my confusion. :rolleyes:
                              I will include a pic of the PCD schematic and econowave schematic so you can see what I see exactly.
                              Click image for larger version

Name:	econowave pcd sim.bmp
Views:	1
Size:	709.0 KB
ID:	1154997Click image for larger version

Name:	Econowave crossover less than 95db 4 OHM.JPG
Views:	4
Size:	22.9 KB
ID:	1154998Click image for larger version

Name:	PCD xover schematic.bmp
Views:	1
Size:	595.8 KB
ID:	1154999.

                              Everything else is coming together slowly.
                              I need to know how to enter the 16 ohm resistor from the econo schematic into PCD.

                              Thanks for your patience.
                              Todd
                              Attached Files

                              Comment


                              • Re: Flex Your PCD Mettle:

                                Hi. I would like to go from active Econowaves to passive, and I want to try the standard HE crossover. Is there a BOM somewhere, maybe with links to the parts at PE?

                                Comment

                                Working...
                                X