I bought the cheapest sub on the planet from parts express for my DML speakers:
https://www.parts-express.com/Goldwood-GW-406D-6-1-2-Poly-DVC-Subwoofer-Shielded-290-352?quantity=1
driving it with a 25 watt plate amp and cross at about 100hz. To me it sounds incredible. I figured it would be good, but not this good. Now I'm getting greedy, and I have another spot by my desk I can fit another 6.5 or maybe an 8 there. A couple questions.
1) the Goldwood specs call for a sealed volume of 0.47ft³. This is huge compared to any other 6.5 I've looked at and even much larger then the few 8's I've looked at. It wasn't a problem, my space limitation is by width, once that's given up, the longer enclosure makes the space somewhat usable because I can set things on top. I would just like to understand the principle behind it, why so much space for this small speaker?
2) I'm happy enough to get another Goldwood, but open to suggestions for both 6.5" and 8". What would really help me is if someone has experience building multiple small subs and can say, for instance, subwoofer A for 75$ just blows away subwoofer B for 25$. Because the cheap goldwood seems to do such a good job, I'm just wondering if it's in the nature of subs, even cheap ones, to get you 90% of what you can get from that size and power.
https://www.parts-express.com/Goldwood-GW-406D-6-1-2-Poly-DVC-Subwoofer-Shielded-290-352?quantity=1
driving it with a 25 watt plate amp and cross at about 100hz. To me it sounds incredible. I figured it would be good, but not this good. Now I'm getting greedy, and I have another spot by my desk I can fit another 6.5 or maybe an 8 there. A couple questions.
1) the Goldwood specs call for a sealed volume of 0.47ft³. This is huge compared to any other 6.5 I've looked at and even much larger then the few 8's I've looked at. It wasn't a problem, my space limitation is by width, once that's given up, the longer enclosure makes the space somewhat usable because I can set things on top. I would just like to understand the principle behind it, why so much space for this small speaker?
2) I'm happy enough to get another Goldwood, but open to suggestions for both 6.5" and 8". What would really help me is if someone has experience building multiple small subs and can say, for instance, subwoofer A for 75$ just blows away subwoofer B for 25$. Because the cheap goldwood seems to do such a good job, I'm just wondering if it's in the nature of subs, even cheap ones, to get you 90% of what you can get from that size and power.
I plugged in different values from woofers and subs, mostly 6.5", and I'm tempted to say the .47 is a misprint. The Vas is also .47, which makes it suspicious. This gives it a Qtc of .89. I'm no expert, but apparently .7 is the sweet spot for sealed enclosures. .89 is by far the highest for the 7 subs I considered, with most .7 - .79. A couple lower values, but then there's this other Goldwood 6.5 woofer (not advertised as a 'sub' for whatever reason even though it goes lower) that comes out at 1.08. So maybe there's just something about these guys being cheap devices.
Ended up ordering the Dayton SD215A-88 8". A couple others I really wanted to try but seems like this is the safe bet.
The 6.5" sub was perfect for getting rid of a stack of reclaimed hard maple flooring I had; was a lot of work to make it usable though. Even with 3/4" maple, that 18$ woofer made me wonder if it's enough. It can really move, so I assume this guy is going to be a monster. I think I'm going to whittle down my stack of frame alder for a core, which is pretty light stuff, but decently strong. From there I can beef it up; we'll see.
The 6.5" sub was perfect for getting rid of a stack of reclaimed hard maple flooring I had; was a lot of work to make it usable though. Even with 3/4" maple, that 18$ woofer made me wonder if it's enough. It can really move, so I assume this guy is going to be a monster. I think I'm going to whittle down my stack of frame alder for a core, which is pretty light stuff, but decently strong. From there I can beef it up; we'll see.
SD215A-88 8 Woofer is a pretty good choice for a small subwoofer. In the near field of your desk top, 10 to 20 Watts should be plenty of acoustic power for your application. EBP is around 80, so either sealed or ported should work. Obviously, a larger box with a port will go lower than sealed. My preference for music has always been for sealed enclosures. Good luck with your project and please, post some pictures. Good luck.
In my experience, if you like the sound of something it is not always the best idea to get 'the next model up' as it were. I have done this several times before I started listening to the music instead of the hifi and been disappointed with my investment. Never forget that sound quality is entirely subjective.
This might be the longest subwoofer build in the history of audio.
got some walnut slapped on the sides, it's thick enough I may be stretching the definition if I call it "veneer". Want it thick enough to to take a small routing profile. can do some really cool looking stuff with veneer, but that little bit of routing can make a big difference.
Finally found a use for this piece of rosewood sitting around for years. One of the worst ever to work; blows my mind people make instruments out of this stuff with hand tools. It should make a spectacular baffle.
got some walnut slapped on the sides, it's thick enough I may be stretching the definition if I call it "veneer". Want it thick enough to to take a small routing profile. can do some really cool looking stuff with veneer, but that little bit of routing can make a big difference.
Finally found a use for this piece of rosewood sitting around for years. One of the worst ever to work; blows my mind people make instruments out of this stuff with hand tools. It should make a spectacular baffle.
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Your cabinet work looks vg for the first attempt, even better. And if it sounds incredible to you thats the entire point.
You might look back from the future and chuckle like I have at some of my speakers. That doesnt count we live in the now. But it helps with overall experience, more importantly the curiosities and fun in it never stops. Its always there keeping you interested.
BTW the very first speaker I built was with pine wood, the laminating stuff for shelves. It worked as good as I needed it to. I was blown away by Pioneer sx750 and big 3 way diy speakers with heavy powerful 12's. That started to hook me on audio initially.
You might look back from the future and chuckle like I have at some of my speakers. That doesnt count we live in the now. But it helps with overall experience, more importantly the curiosities and fun in it never stops. Its always there keeping you interested.
BTW the very first speaker I built was with pine wood, the laminating stuff for shelves. It worked as good as I needed it to. I was blown away by Pioneer sx750 and big 3 way diy speakers with heavy powerful 12's. That started to hook me on audio initially.
I was able to get the speaker hole cut today and fits snug, but won't post because it's a bit embarrassing. My first subby, for the 6.5", I cut the template perfect the first time and I guess I was confident. For the 8", I cut 3 templates and f'd up all of them and no more mdf. Since the final one was too small by a bit, I opened it up freehand for a good fit but not pretty. So I used that template and the speaker fits nicely and good thing it covers the hole.
Turns out I have a pic of the top in production. It hit me that now is a good time for a trial run with a starburst, something in the back of my mind for years and never got around to it so I went for it. Was rushed and it was a pain, but turned out good enough for a sub.
W went shopping tonight so suddenly have some free power tool time, so burned through a cleanup with belt sander and RO and since I'm out of grain filler threw on a first poly coat to raise grain and I'll get it flat enough that way.
Turns out I have a pic of the top in production. It hit me that now is a good time for a trial run with a starburst, something in the back of my mind for years and never got around to it so I went for it. Was rushed and it was a pain, but turned out good enough for a sub.
W went shopping tonight so suddenly have some free power tool time, so burned through a cleanup with belt sander and RO and since I'm out of grain filler threw on a first poly coat to raise grain and I'll get it flat enough that way.
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It looks better than my first box build. Practice and try to buy some tools in priority along way.
What did you use for cutting?
I bought a compact Bosch router with spiral cutting bit then made a circle cutting jig that makes it pretty much impossible to mess up the baffle. My routers get more use than anything in the box.
What did you use for cutting?
I bought a compact Bosch router with spiral cutting bit then made a circle cutting jig that makes it pretty much impossible to mess up the baffle. My routers get more use than anything in the box.
If you mean the template, it was cut on a router table with a porter cable 8902 and a carbide spiral bit. No problem with that thing cutting clean. However, the idiot doing the cutting didn't clamp down hard enough the first time so it moved. The other two failures were because I'd measured wrong. Unless I missed it, Dayton doesn't provide the radius for the hole. So how do you measure it? Well, if I were to do it again, I'd wrap a string around the housing to get the exact circumference. I was really rushed due to too much multitasking including building my DML panels that take up lots of working space in my small shop.
Things have slowed down now so the last half of the build has been more enjoyable.
Things have slowed down now so the last half of the build has been more enjoyable.
I think the modern method of making a circle in ancient Greece was string 😉
If you don't have a compass two holes in a ruler works great too.
If women don't find you handsome they better find you handy.
If you don't have a compass two holes in a ruler works great too.
If women don't find you handsome they better find you handy.
Subby's little brother is finished. Pics with the brothers together and then the DML speakers I built that they are enhancing bass for. The dimensions weren't my first pick design wise, but to fit the space he's going to occupy. The back doesn't match great but would rather get rid of scrapwood since it will never be visible. The sides also; I could have book matched the walnut or used Peruvian walnut which would have looked killer, but sides won't be visible either and the one side picked up sapwood anyway so this was a good application for it.
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As for sound, I think it's working correctly and it's going to have some bounce to it. With hard rock, nothing too crazy, it's definitely putting out some bass and it's barely moving. I've got another sub amp on the way so right now I just have the 25 watt Dayton plate amp that's been driving original subby.
My first impression is the original 6.5" Goldwood sub is a perfect match for the DMLs and at low volumes it sounds better, although, the 8" Dayton isn't in its place yet and its test spot is not as good as it's brother's. I anticipated this actually, and I may have mentioned my original plan was to buy 3 of the Goldwood subs when they were on sale for 15$, but, those subs are (I think this the right technical term) high Q and require a very large enclosure for their small size and wasn't going to work.
I think the reason is that while my DML's put out pretty good bass for panel speakers, the Goldwood barely qualifies as a sub and is more of a mid-bass, or just a woofer, and so it's filling a gap you wouldn't have with conventional 3-way cones.
So here's one example: on some rando jazz I was listening to, you've got the bass walking around, and with the Dayton, it's uneven because as it gets lower the sub really kicks in while the Goldwood is seamless. Crossover point is the same for both at 80-100 hz. Granted, I had the sub turned up too high, but I turned it up because it wasn't filling in the sound. Now, I could have gotten another Goldwood or maybe two of them, but the hope is that once the other amp comes, the Dayton will handle true lows that the Goldwood can't. The drawback of the Goldwood is that these things really move at mid-volume. The DML panels can be removed from the wall area and set up in the center of the room in a more normal listening arrangement, and it's 200w going to those and they can really crank. So subby can't really keep up. If I can find room for a second goldwood ...maybe...
My first impression is the original 6.5" Goldwood sub is a perfect match for the DMLs and at low volumes it sounds better, although, the 8" Dayton isn't in its place yet and its test spot is not as good as it's brother's. I anticipated this actually, and I may have mentioned my original plan was to buy 3 of the Goldwood subs when they were on sale for 15$, but, those subs are (I think this the right technical term) high Q and require a very large enclosure for their small size and wasn't going to work.
I think the reason is that while my DML's put out pretty good bass for panel speakers, the Goldwood barely qualifies as a sub and is more of a mid-bass, or just a woofer, and so it's filling a gap you wouldn't have with conventional 3-way cones.
So here's one example: on some rando jazz I was listening to, you've got the bass walking around, and with the Dayton, it's uneven because as it gets lower the sub really kicks in while the Goldwood is seamless. Crossover point is the same for both at 80-100 hz. Granted, I had the sub turned up too high, but I turned it up because it wasn't filling in the sound. Now, I could have gotten another Goldwood or maybe two of them, but the hope is that once the other amp comes, the Dayton will handle true lows that the Goldwood can't. The drawback of the Goldwood is that these things really move at mid-volume. The DML panels can be removed from the wall area and set up in the center of the room in a more normal listening arrangement, and it's 200w going to those and they can really crank. So subby can't really keep up. If I can find room for a second goldwood ...maybe...
How come you made the other enclosure much nicer?
I was looking at the way you laminated the boards, is it causing any leaking or vibration?
Good bar clamps are worth there cost a thousand times over. Especially for laminating boards lengthwise. It looks like you glued every other board on the end grain. It may work itself apart from expansion and/or sound pressure. Plus glue doesn't like to stick as well as it does on side grain. It looks ok other than that.
I was looking at the way you laminated the boards, is it causing any leaking or vibration?
Good bar clamps are worth there cost a thousand times over. Especially for laminating boards lengthwise. It looks like you glued every other board on the end grain. It may work itself apart from expansion and/or sound pressure. Plus glue doesn't like to stick as well as it does on side grain. It looks ok other than that.
I usually measure the outer diameter and use a caliper to deduct the space behind the ring.
Thats how I do it usually. When extra carful I use a caliper to make a ring template so I can trace it directly on the baffle. Then double check that. That mistake can be a big mistake, one I have made once. Now I triple check, quadruple, before the cut.
Not sure I understand the critique of the laminating and possible leaks -- I think you mean the strips covering the end grain, but I did that for every end on the original subby out of necessity. Subby 1 is made from a load of maple flooring a friend gave to me and it has lines (for glue?) on the underside. For new subby, I just covered the end grain on top to make a complete border for the starburst. With the bump 25w can produce, it feels at least as solid as the original, mostly due to the increased width, I think. I don't have any stability concerns or leak concerns with it, except there is a visible hair-line gap in places between the rear plate and the body. On both units, the back is screwed on with basic silicon glue to make the interior more accessible for unforeseen circumstances should I need more room than the speaker hole. If that becomes a problem, I can add more screws, as subby 2 has fewer, or fully commit and deploy the big Bessey IBEAMs and Titebond II.
Of course, I could be wrong, and if it begins to fall apart structurally then I will be forced to make another one.
Of course, I could be wrong, and if it begins to fall apart structurally then I will be forced to make another one.
In other news, Subby 2 is in its home now and barely fits, but it fits. I still think with accoustic guitar, Subby 1 sounds better, but deep drums etc., 2 is doing it's job and substantially bigger on the bottom end.
The second one went smoother and faster. Except I didn't shave quite enough off the circumference, the cement was tacking up. I wasn't sure if the baffle would seat the full 1 1/2" without breaking it with the mallet. But I managed. It probably self sealed without cement its that snug, but why risk it. I silicone the inner joint too. Everything gets extra done or else over done in my shed.
It takes me more or less a whole day to make and install one baffle. The cut for the speaker is last, so yea, no I might cry if I cut it wrong. I leave it intact because it makes the other steps easier. If I had a full shop I'd do some of it differently.
Laminate just means to join one or several pieces along the edge grains to widen boards, and flat side's to add thickness. Clue and clamp them together, its as easy as that. You need a jointer for side edge grain if you want them 90 degree. If the store's source hasn't already machined them.
It takes me more or less a whole day to make and install one baffle. The cut for the speaker is last, so yea, no I might cry if I cut it wrong. I leave it intact because it makes the other steps easier. If I had a full shop I'd do some of it differently.
Laminate just means to join one or several pieces along the edge grains to widen boards, and flat side's to add thickness. Clue and clamp them together, its as easy as that. You need a jointer for side edge grain if you want them 90 degree. If the store's source hasn't already machined them.
