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    B40 replacement driver

    So both my B40's have issues with their drivers....of which one has a 3" voice coil and the other has a 4".
    Opinions/Comments on this Dayton driver for use as a replacement?!
    https://www.parts-express.com/dayton-audio-um15-22-15-ultimax-dvc-subwoofer-2-ohms-per-coil--295-514
    Allen 5300-DK, Hammond A-105, Conn Custom 905-DK

    #2
    Looks like an impressive driver! I'd be tempted to try it just for coolness factor There are probably specification factors that may or may not make that driver suitable though, and I suspect someone will weigh in on that (toodles is very helpful with those kinds of things).

    What's wrong with the existing drivers? I ask only because if the problem is a foam deterioration issue that is easy enough and cheap to fix. I've used Springfield Speaker Repair to get replacement surrounds and they seem to have quality surrounds and their guide is easy enough to follow if you don't already have experience. Just a thought...
    Viscount C400 3-manual
    8 channels + 2 reverb channels (w/ Lexicon MX200)
    Klipsch RSX-3 speakers and Klipsch Ultra 5.1 subwoofers

    Comment


      #3
      The subwoofer guys should like this unit. With an xmax = 19mm you can get 100dB SPL @ 1 meter at 16HZ.
      Since a 500watt flood lamp gets very hot, I wonder how hot the speaker gets running at 800 watts for 10 minutes?

      Comment


        #4
        That's one of the very few subwoofers that has a chance to work down to 16 Hz vicinity, but it's a lot of money. Before I spent that, you ought to at least get a price on a replacement from Allen. Spare parts from Allen are never cheap, but neither is that subwoofer.

        You might consider this alternative: https://www.parts-express.com/dayton...4-ohm--295-206 at about half the price. Should get to 17.5 Hz in the B40 cabinet, though you might have to change the tuning from what the original drivers used (different port length).

        Comment


          #5
          I know folks want to get down to 16 Hz with their subwoofers, but I doubt that the B40 was designed to use one of those ultra-compliant woofers. And I am sure it was originally built with an ordinary 8 ohm driver. Trying any kind of exotic driver in it would be purely experimental and might result in a very poor match with the box and the port.

          Keep in mind also that the Allen stock amplifiers produce no more than 100 watts per channel. So any kind of woofer that can absorb a kilowatt is overkill for sure. And many of the exotic high-excursion drivers actually require more power than a simple Allen amp can comfortable produce.

          I haven't had to replace one of those drivers, but just looking at it, I'd assume it has a rather ordinary textile-accordion surround, not nearly as compliant as the expensive drivers so often used in exotic sub designs. It's probably a plain vanilla Eminent high-power 15" woofer, such as the "Gamma" woofer.

          I'd be inclined to replace it with something like this:

          http://www.mcmelectronics.com/produc...-2983-/55-2983

          Yes, the bandwidth isn't specified to go down to 16 Hz, but if you look at the published response curve, you'll see that it still has appreciable output below 20 Hz. And installed in the B40 box it will surely knock your socks off.
          John
          ----------
          Church: Allen MDS-45 with Allen MIDI-DIVISION-II expander
          Home: Allen Renaissance R-230 with expanded four-channel audio and MIDI-DIVISION-II
          Shop: Bunch of organs in varying conditions, some good, some not...
          Half of an incredible two-man organ service team -- servicing all the major digitals in Arkansas churches
          https://www.facebook.com/pages/Birds...97551893588434

          Comment


            #6
            I wouldn't go with that mcm driver--the audio engineers at Allen understood loudspeaker design theory, and it's very unlikely they chose a woofer with a resonant frequency of 44 Hz. Whatever anyone wants to think, the laws of physics apply to loudspeaker design even when used with organs, and you do need a very low resonant frequency to get below 32 Hz response. The response doesn't have to be flat, but the roll off does need to be smooth.

            I think I've mentioned this before, but it definitely bears repeating: OEM manufacturers of organs can get custom designed drivers from Eminence and others very easily, and these drivers are not available for sale to the general public. When doing so, builders like Eminence are going to use relatively stock components, like frames, surrounds, and voice coils, with some tweaking. In case of a woofer for this cabinet, they very likely went with a much heavier cone to lower the resonance.

            I do suspect that in some cases Allen has used very high compliance speakers, as some of their sub bass cabinet crossovers incorporate a high pass filter set around 16 Hz to prevent excess cone excursion.

            It would be best if someone who owns a B40 cabinet could remove the driver and run it through something like the Parts Express woofer tester so we could have the Thiel Small parameters. I don't have a B40, but I do own 2 of the B20's. I should test those drivers, but from the outside they look like very high compliance drivers.

            Comment


              #7
              Thank you all for your comments and suggestions! I 'm still wondering what originally came in the B40 since each of mine (2) have what appears to be the exact looking driver except one is a 3" VC and the other is a 4". I have a pair of copycat B20's (Think Goulds music...Pasadena) that were made in the early 80's for a MOS 301 organ. I tried them last night. They work fairly decent though only at very low volume or soft celeste type settings. As soon as you get to a moderate volume, though not loud, you instantly lose the bottom end. If I crank up the outboard amp (TOA 250 watt per Ch....Freq Response 10-30k) the woofer immediately starts over excursion.
              I might take that advice above and get ahold of Allen and see if the original or newer replacement is available. I know this subject of "sub-woofers has been exhausted here on the forum but my question is more of what can be a good or better replacement driver in a Allen B40 rather then build from scratch
              My current B40 drivers were reconed by OC speaker just before they closed their shop. One of the Drivers has developed a "open" in its windings and the other is the 3" VC...it works but since I'm going to have to fix the open driver I might as well match them up correctly
              Allen 5300-DK, Hammond A-105, Conn Custom 905-DK

              Comment


                #8
                Update:

                I ended up buying 2 Dayton Sub Woofer Drivers (https://www.parts-express.com/dayton...4-ohm--295-469) and installing them in my B-40's as replacements. I went into this project wondering if I was just kidding myself due to box size, interaction of of said box size and venting vs driver...etc. Well, the new drivers would not fit right into the stock round hole because the basket struts of the driver protrude out further than the stock Allen driver. I was contemplating cutting the existing hole out larger but saw that the wood insert nuts on the back side were right at the edge. So I came up with using 1/2" plywood as a spacer and cutting the hole for the speaker via using the cardboard packing as a template. Worked like a charm.
                So the big test.........works great! I have 2 of these Allen B-40 cabinets and wow!! what an awesome sound/feel!! I highly recommend these as replacement drivers!
                I was using 1 TOA P75D Amplifier and then found another amp exactly like it and now I'm running 1 amp bridged per subwoofer......just awesome!
                Allen 5300-DK, Hammond A-105, Conn Custom 905-DK

                Comment


                  #9
                  The math says that that driver in the B40 box ought to be able to produce pretty astounding results--good to hear it worked out!

                  Comment


                    #10
                    First, you can get replacement voice coils from the companies that sell speaker repair parts - cheaper than buying a new driver - Allen's price is well over $100.

                    Second, and as I now read below it may be too late, I may have that driver. look on the back of the B40 driver for an Allen part #, something like 292-xxx.
                    john
                    Can't play an note but love all things "organ" Responsible for 2/10 Wurli pipe organ, Allen 3160(wife's), Allen LL324, Allen GW319EX, ADC4600, many others. E-organ shop to fund free organ lessons for kids.

                    Comment


                      #11
                      Hopefully you can see the drivers. I still have to remove them and the plywood spacer and paint the plywood spacer and clean up the rest of the wiring along with mounting the amps in the rack.
                      Attached Files
                      Allen 5300-DK, Hammond A-105, Conn Custom 905-DK

                      Comment


                        #12
                        That's quite a hefty looking driver! Glad it worked for you.
                        John
                        ----------
                        Church: Allen MDS-45 with Allen MIDI-DIVISION-II expander
                        Home: Allen Renaissance R-230 with expanded four-channel audio and MIDI-DIVISION-II
                        Shop: Bunch of organs in varying conditions, some good, some not...
                        Half of an incredible two-man organ service team -- servicing all the major digitals in Arkansas churches
                        https://www.facebook.com/pages/Birds...97551893588434

                        Comment


                          #13
                          This would be a great replacement.....low fs, high efficiency and adequate power handling.....plus excellent reviews from users and sorta cheap.

                          https://www.parts-express.com/dayton...4-ohm--295-206

                          Comment


                            #14
                            That one (the cheaper one) looks like an Eminence or a Chinese Eminence knock-off, and is probably much closer to the original Allen driver than the more exotic driver that Hamman used. But the more exotic one probably does a better job, at least if it works well with the B40 cabinet. The catalog description indicates that it can work even in a smaller box, so it probably loves the B40 enclosure.

                            We have a job coming up that will call for replacement of the enormous woofer in an Allen SR-5. It's a 15" driver, but really unusual in that the rubber roll around the edge is very wide. I suspect the driver has an extremely low free air resonance, super compliant. And somehow matches up with the pair of 15" passive radiators in the same box. I'm planning on paying the money, whatever it costs, to get an exact replacement from Allen, on that job. I always have excellent luck with Parts Express speakers (and even cheaper ones from Newark, etc.) but for a very new Allen SR-5 I'm taking no chances. (The cone has been chewed up by a squirrel.)
                            John
                            ----------
                            Church: Allen MDS-45 with Allen MIDI-DIVISION-II expander
                            Home: Allen Renaissance R-230 with expanded four-channel audio and MIDI-DIVISION-II
                            Shop: Bunch of organs in varying conditions, some good, some not...
                            Half of an incredible two-man organ service team -- servicing all the major digitals in Arkansas churches
                            https://www.facebook.com/pages/Birds...97551893588434

                            Comment


                              #15
                              (The cone has been chewed up by a squirrel.)

                              Time to also add a squirrel proof grille to the speakers.
                              Ed Kennedy
                              Current Organ - Conn 645 Theater

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