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  • #16
    Originally posted by Chris Roemer View Post
    Thing is, 10" 2-ways are virtually unheard of. (I KNOW they were popular back in the '70s, but not much was known/understood about speaker design back then - it was very much trial-and-error). Even 8" 2-ways are pretty uncommon. You'd have to read/understand off-axis dispersion (or driver "directivity") to appreciate this. Basically, above a certain freq. a 10" driver will "beam" (like a spotlight) - and this may be as low as 1000-1500 Hz. When a designer "in-the-know" sees a 10" that can play up to 8000 Hz, they basically ignore everything above 1.5-2k anyway (so should you).

    A "wave guide" is sometimes used to throttle back the (very wide) dispersion of a dome tweeter so it can be used more successfully with those big(ger) woofers.

    A good read is "SpeakerBuilding 201" by Ray Alden - available... guess where?
    What would you do in a case like mine then? I have next to no experience in the speaker building hobby and was hoping to just mess around with something I already have rather than design something from the ground up, which is the direction this seems to be going now. Bottom line here is I have 2 cabinets with 3 drivers each and I want to put decent drivers and a simple crossover in them and hopefully come out with decent speakers for what I've paid in drivers. I don't need a super flat response and I don't want to build a super complicated crossover considering it's my first time. Is this unreasonable for someone with no experience? This will likely be a project I'll iterate on in the future I just want to get a good start on it and learn along the way.

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    • #17
      Do you have any woodworking tools, or a place to work? Does your old (4"?) mid have a "cup" behind it (its own enclosure - so it's not pressurized by the 10" woofer)? It's VERY likely that you can't find drivers to "drop in" the existing holes. Even if you buy some (by "spec'd" frame O.D.) you might find that the through-hole (through the front baffle) is 1/16" or 1/8" too small to drop the driver in. Then what? Are your current drivers "flush mounted" - meaning the frames are cut down into the baffle - or surface mounted (where they stand proud)?

      The DSA270 is a worse fit in your box (parameter-wise) than the DC250. You can model these things yourself using the FREE WinISD from linearteam.org .

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      • #18
        I have the tools I need to enlarge the holes enough for larger drivers if need be and all the drivers are being surface mounted. I would rather not replace the whole front baffle if I can get away with the one that's already there. If I did replace the baffle I would section off the 10" from the other drivers in its own chamber with some poly-fill in there. Right now I'm just doing a bunch of research to find what speakers and tweeters would work best together and how I would go about designing a 3-way crossover since that's turning into a necessity. I'm not trying to delve super deep into the design process since this is my first project, I'm just trying to throw something together that will work and that I can improve on later. Once I have a good set of quality drivers and have practice wiring and tuning crossovers then I'm planning on working on building a proper enclosure to house them in or start a new project. As of the moment though I'm not looking to build a 100% perfect set of speakers, I just want to know what will work good together and how it all sounds once it's assembled. To be honest, after getting all this input and seeing how much more complicated it is than I thought it would be, I might just buy a pair of emotiva B1 speakers and be done with the idea of building my own.

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        • #19
          Can you post a picture of your speakers showing drivers and baffle. I linked a perfectly good 3 way by a competent designer. Did you look at it?

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          • #20
            Sorry, I must have glazed over the link you posted but I just read all the way through it and it seems more promising than any of my other options and for a good bit cheaper. These are the cabinets with the original 10" and mid, I frankensteined a tweeter I had laying around onto it just to mess around

            Click image for larger version  Name:	20181105_165937.jpg Views:	2 Size:	720.7 KB ID:	1392889
            Attached Files

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            • #21
              No need to make a whole baffle really. You could/should cut round "plugs" from MDF, and fill old holes using epoxy or construction adhesive. From the main PE page, goto Technical Resources and look at the "Woofer Selection Guide" (WSG). Pick a 10" (if you insist) that'll work in your box volume (about 1.8cf). You can sort the data by clicking on the comlumn header (ex: clicking on "sealed box volume" - or whatever, will sort all enclosures by size, then scroll down to your box size (maybe look at 10"ers that'll work in 1.5-2.0 cf). A "closed back " mid will make it unnecessary to cordon off your box internally to protect the mid (which is already getting small for a 10"). MOST of those are 5" though, I think (not 4"). Nothing wrong w/the Dayton tweeters that it looks like you already have.

              Your tweeter should be at seated ear level (30"-34" typical) w/the mid as close as possible underneath. The woofer can be higher, or closer to the floor, or where YOURs is now. You won't have to learn XO design, as there are peeps on here that'll do that for you (like me), the only thing is that you have to pick drivers that have published graphs for freq. resp. and impedance.

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              • #22
                Alright that sounds reasonable, I'm really hoping to keep the original 10" cutout but if that's going to negatively impact the final design a lot then I guess I could try to plug it with MDF and us a different size driver if it'll work better. I'll scope out some drivers in the selection guide and post back here, thanks for the help I appreciate it.

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                • #23
                  So, now im looking at the Dayton DC250-8 as the 10", the GRS 5SBM-8 as the mid (Can't find graphs for any of the sealed mids), and the Dayton PT2C-8 as the tweeter. I couldn't find any good 8" drivers rated close to the sealed volume of the cabinet but the dayton 10" seems like it would be alright. If there's anything wrong with the woofer selection let me know.

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                  • #24
                    if you already have the DC250 and DC28, you could build these: http://techtalk.parts-express.com/fo...waynej-s-lyras (just add the dome mid).

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                    • #25
                      Right now I have no drivers except spare ones lying around from old speakers.

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                      • #26
                        Ok after doing a bit more research and driver hunting I've found a sealed midrange with graphs posted (Goldwood GM65/4), a tweeter that I think will be a good match with the midrange (dayton RST28F-4), and it looks like the dayton DC250-8 is the only driver that has a good sealed volume rating for my cabinet. Unless there's a good reason I should swap these out then these are the drivers that I'm deciding on and any help designing a suitable crossover would be very much appreciated.

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                        • #27
                          I'm PM'ing you.

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