SEOS12 and AE TD12M design

Discussion in 'DIY Speakers and Subwoofers' started by BillWaslo, Sep 22, 2012.

  1. Robot bunny, I want to see a build thread with lots of pictures from you! It sounds like you have built a winner.
  2. Bill, as far as the treble goes, I thought the shaping was perfect. I did consider building that section of the crossover in a modular fashion in advance so I could adjust easily, but it doesn't need it to my ears...and I'm gonna trust those until I can eventually measure the system accurately. Honestly though, after listening for about an hour in various positions around the room, I'm extremely pleased. The mids and highs blended seamlessly.

    Here's the gallery of my build:
    Build Thread:
  3. Here's another source for the 3.5 mH coil
  4. one-stop shoppers rejoice!
  5. Is it fine to use for L1 since 255-046 is out of stock? Strange since Amazon says PE as 12 in stock.
  6. Sure, no problem with that.
  7. Erich,

    Do you have an eta on the baffles or flatpacks for this project and the Daniels?

  8. Erich,

    I've been checking in daily to see a flatpack for the td12m. I will assume since it is close to christmas that we will not see it, but will be looking for it after christmas.

  9. Hey bwaslo, would the following work well together and would it be difficult to set up in a digital crossover? TD12M with SEOS Fiberglass Raal and a minidsp. Also why not use the TD12S since it has a higher qts and qes. Correct me if I'm wrong but I recall that having a higher qts/qes makes it more suitable for a sealed configuration. Would the Raal tweeter be serious overkill or would I be better off with a DNA-360 or perhaps a BA-750? I'm looking for the best sound quality for music period. Movies I'm not to worried about. I'll just turn up the volume and add a higher wattage amp.
  10. Should work, Bill lists a max 0.4ohm DCR for that coil and the Erse 18awg I-core is within that number.
  11. Thanks.

    RobotBunny suggested I use this one instead, so I bought 3.
  12. Hope you don't mind I used your files Bill. I checked I was using them correctly by inputing your cross over first. These should work ok.

    LR4 (linkwitz Riley 24db/oct) @ 1000hz
    No delay
    No level
    No eq

    BW2 (butterworth 12db/oct) @ 1700hz
    Level = -11db
    Delay = 0.22ms
    3500hz, -5.0db, q = 0.8
    2300hz, -2.0db, q = 2.0
    8000hz, -2.0db, q = 1.0
    1300hz, +2.0db, q = 1.5
    19,000hz, +6.0db, q = 1.0 (optional)

    This is only a simulation. I've never used these settings.
  13. JFA , sorry I missed your post questions. The TD12S would give lowest bass in smallest box. I don't know much about the RAAL, so nothing to say on that, sorry. But the SEOS12 and dna360 does more than fine on music.


  14. To use the RAAL tweeter, you'll need a dedicated midrange between it any AE 12" woofer. Without the SEOS waveguide, I wouldn't use the large RAAL below 3K...and the waveguide doesn't appear to have enough loading to seriously decrease it's effective range.
  15. I ordered my 3- AE TD12M's today and am working on ordering the correct parts for the passive crossovers.

    I have the majority of the items in checkout at PE, however I had a couple clarifying questions concerning the crossovers before I submit my order to PE.

    1. As already noted, the PE part number for L3 3.5mH Inductor (266-569) returns as invalid. I saw several alternatives listed here but wanted to make sure this (266-916) is a proper replacement for the intended inductor?

    2. Also as already noted, C2 (027-415) shows up as 2.2uF on PE. Is the schematic missing the .2 or do I need to source a 2uF cap?

    3. I was reading through RB's thread on AVS and he noted he used 14ga wire for interconnecting components he ordered from Meniscus. Is there a note about the preferred gauge wire to use? Is there an alternative that PE carries? I was unable to find anything that was not sold in bulk. I do have a lot of 16 and 14 gauge speaker wire left over from other projects. Would this be ok to utilize? Also, where would I source the solid copper wire used in the center of the board.

    Sorry for all of the questions. I just want to make the correct selections before I order.
  16. Hi Chris,

    For the 3.5mH go with 266-560 (sorry for the typo). 266-916 would work, too, but I don't see the need to spend twice as much for it.

    2.2uF is right. I forgot to update the schematic value for the part number.

    The wire between parts will be so short that the wire gauge is pretty much irrelevant. Even #26 would work. A good source of heavy solid wire (if you want to go that way) is to use the wire in "Romex" type house wiring. Or you could strip the insulation off stranded speaker wire, twist it tight and "tin" it with solder to make it solid. But any wire you're likely to use will be fine electrically, though heavier might be easier to keep solid on the mounting board.
  17. Awesome! Thank you Bill. Hoping to finalize my order tonight.
  18. Was 2.0uF actually the calculated value? I have a couple matched pairs of 1.0uF polystyrene/foil caps (wired in parallel) that I had already purchased for use in this crossover. Alternately, if 2.2uF is indeed closer to the calculated value, I have some .22uF teflon/foil caps I could also parallel. Please let me know.

    I agree on the Romex suggestion. I have a roll I purchased for "GND" wire and crossover applications. At any rate, I would not use a wire of any larger gauge (smaller diameter) than the inductors in the crossover, but that's because I'm a sucker. ;)
  19. Go with 2.2uF. I usually tweak a model using continuous values and then substitute standard values then tweak again with those. Other values are varied to best fit when going to a standard value so you don't want to back up on just one component.

    On wire gauge think in terms of resistance. An inch of 26AWG has way less resistance than the many, many feet of (say) 20WAWG of a coil. If there are actual resistors in series there, the wire gauge is totally in the noise. In fact if there is a resistor in series with a coil, it is good to leave the coil's wire gauge (dcr) alone - using a thicker gauge there is NOT an upgrade. I try to use lightest gauge there and design the extra series resistance into the network.
  20. Thanks for clarifying in regards to the capacitor. I've found myself with an assortment of inexpensive Russian capacitors to play with, so I'm glad to have my values straight.

    I grasp the wisdom in what you're saying: any series resistance get's lumped into an inductor's DCR anyhow, so why not opt for a more lossy inductor which cuts cost and component count. Makes good sense.

    Along these lines, I was wondering if a 3.6mH (0.23 ohms DCR) inductor could be substituted for the 3.5mH (<0.4 ohms DCR) inductor (L3 in the schematic)? I could also have it slightly unwound to drop the inductance a tenth of a milliHenry.
  21. Yeah that should work fine. No need to unwind turns.

  22. Hi Bill,

    Were any horizontal/vertical polar measurements made around the crossover frequency?

  23. Unless Bill posts otherwise, I'm pretty sure he never physically built the actual crossover. The crossover was designed via measurement & simulation. Not sure if anyone who built this speaker took any polars.
  24. To anyone who has built these, I am stuck on the enclosure volume. Unlike RB I have no real space constraints. I plan on using the same 50Hz tuning via a slot port but have not been successful in using any modeling software to consider volume and keeping the air speed in the port in check. Any help would be greatly appreciated.


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