Announcement

Collapse
No announcement yet.

How are you suppose to enclose Planar Transducers for midrange?

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

  • How are you suppose to enclose Planar Transducers for midrange?

    I want to try a project using Neo8-PDR planars for midrange xo 300 to maybe 2k while I'll play around with with an active crossover, but I have never used planars before. Does enclosure volume matter with these for midrange use and does it need a separate enclosure from woofer/tweeter? I would like any advice on the proper usage.

  • #2
    I have not used them either, but from other comments, I believe it should be large enough not to damp the diaphragm, and I have seen them tapered as to reduce refection. Usually stuffed away from the driver.
    Their own chamber of course. BG intends them to be di-pole on a large baffle. Keep us posted. I would love to see their response without the drop off a di-pole baffle.

    Comment


    • #3
      I'm trying the Neo8 in a 3" deep waveguide for midrange and up, in a 2 way system. I haven't done much beyond a prototype using a NE315W-08. I know this is unconventional. I'm using a MiniDSP HD and Sure 4 channel amp. So far the sound is promising. Paul K generously designed a T/L chamber for the NE315, and the Neo 8 is in a separate open back chamber. I have only the one cabinet, the other is similar, but includes an NE265W-08 and a HiVi RT2C(?) tweeter. This configuration is definitely not worthwhile, and I have replaced the planar driver with the Peerless Corundum dome. The NE265 and Corundum dome are promising. I know the above is a bit off the topic, but mention it as I have an extra prototype waveguide you can have for the cost of shipping.

      Comment


      • #4
        Everything you need to know is right here, including 'a carefully designed rear enclosure provides additional equalization at the low end of the reproduced frequency spectrum.' https://www.parts-express.com/pedocs...ions-44311.pdf
        www.billfitzmaurice.com
        www.billfitzmaurice.info/forum

        Comment


        • #5
          Application note only has the one comment. It does not say anything about what that "carefully designed enclosure" is, which was Fusion's question.
          This was covered probably over in DIY , maybe 10 years ago. Rings a bell. Back when their 6 footer was all the rage.

          Comment


          • #6
            Keep us posted on the Peerless. It, as well as the new SB ceramic caught my eye. They look easier than the Seas to implement and way less expensive than the Transducer Tech.

            Comment


            • #7
              Originally posted by tvrgeek View Post
              Application note only has the one comment. It does not say anything about what that "carefully designed enclosure" is.
              You can't exactly plug the driver specs into WinISD. In this case carefully designed means the old fashioned way, seat of the pants trial and error.

              www.billfitzmaurice.com
              www.billfitzmaurice.info/forum

              Comment


              • #8
                I used the Neo8 in a 3--way design, the Amaroso, in 2012. I've attached a photo of the complete system. The Neo8 is in a compartment with internal dimensions of 10"W x 12"D x 8"H which is a short, tapered TL with a deflector at its rear and exiting a vertical slot thru the back panel. I've attached drawings of the whole cabinet side view and a top view of the Neo8 compartment. The 1/4-wavelength resonant frequency of the tapered TL was 400 Hz, and the primary goals of the midrange enclosure design were to eliminate back-wave reflections through the driver and reduce standing waves, while providing a controlled rear output for a small enhancement of soundstage spaciousness and depth, yet allowing the cabinet’s back to be fairly close to the wall.
                Paul

                Paul Click image for larger version  Name:	100_0615.jpg Views:	0 Size:	122.5 KB ID:	1449042 Click image for larger version  Name:	Amaroso Cabinet Sideview.jpg Views:	0 Size:	304.0 KB ID:	1449043 Click image for larger version  Name:	Amaroso Midrange Enclosure.jpg Views:	0 Size:	198.0 KB ID:	1449044

                Comment


                • #9
                  If i were to try one, I would build a triangular chamber about 5 inches deep and stuff it. As this is a midrange with limited displacement, I would expect it to have no loading effect. Stuffing and angles dealing with the back wave . I would use OC 507 for the stuffing. My first guess. Bigger as Paul has done could be better.
                  So, the correct answer is PROTOTYPE.

                  Comment


                  • #10
                    Originally posted by Fusion916 View Post
                    I want to try a project using Neo8-PDR planars for midrange xo 300 to maybe 2k while I'll play around with with an active crossover, but I have never used planars before. Does enclosure volume matter with these for midrange use and does it need a separate enclosure from woofer/tweeter? I would like any advice on the proper usage.
                    Whoa. The Neo8-PDR is a tweeter! I used them for a number of years on OB. Xo was 1.7kHz initially, but I raised it to about 2.2kHz because I thought it sounded better there. LR24 (4th order) high pass on a digital processor. No way can they play down to 300. They now make a Neo8-S version that goes lower, something like 800Hz in a single, maybe lower in a line of them. But I think you really need the Neo10 if you want to go to 300. For close to $400. Erin's Audio Corner (?) has a test of them.
                    "She don't love my speakers anymore..."

                    Comment


                    • #11
                      In the enclosure design for the Neo8 in the Amaroso, the 400-Hz, 1/4-wavelength resonant frequency from the short, tapered TL raised the low-end response of the Neo8, resulting in it being successfully crossed at 610 Hz and 2.7 kHz.
                      Paul

                      Originally posted by wavefunction View Post

                      Whoa. The Neo8-PDR is a tweeter! I used them for a number of years on OB. Xo was 1.7kHz initially, but I raised it to about 2.2kHz because I thought it sounded better there. LR24 (4th order) high pass on a digital processor. No way can they play down to 300. They now make a Neo8-S version that goes lower, something like 800Hz in a single, maybe lower in a line of them. But I think you really need the Neo10 if you want to go to 300. For close to $400. Erin's Audio Corner (?) has a test of them.

                      Comment


                      • #12
                        For a simpler approach, you could review my Matrix Revolution writeup (access from my website or search the Tech Talk forum). Those had a 1.5" thick baffle. I had a rectangular cutout through the full baffle and basically attached a back plate to that. I didn't tightly seal the wire holes because I didn't want the chamber to pressurize, and I used loose polyfill as stuffing. The low end rolloff was well-behaved and the speaker performs well.
                        Keep an open mind, but don't let your brain fall out.

                        Sehlin Sound Solutions

                        Comment


                        • #13
                          Thought I should clarify that I didn't come up with the Neo8's enclosure design for the Amaroso; it was Dan Neubecker's idea. He was going to design the crossover and thought this midrange enclosure would be a good choice. I built a text box for it where the triangular deflector between the tapered TL's end and the exit slot on the back panel was movable fore and aft over a couple of inches. I shipped the test box to Dan where he determined the optimum location for the deflector as well as the stuffing regimen.
                          Paul

                          Originally posted by Paul K. View Post
                          In the enclosure design for the Neo8 in the Amaroso, the 400-Hz, 1/4-wavelength resonant frequency from the short, tapered TL raised the low-end response of the Neo8, resulting in it being successfully crossed at 610 Hz and 2.7 kHz.
                          Paul


                          Comment

                          Working...
                          X