Techtalk Speaker Building, Audio, Video Discussion Forum - Tech Talk Forum http://techtalk.parts-express.com/ Want a second or third opinion about your speaker cabinet design or other audio related problem? Post your question or comment on the Technical Discussion Board. Hundreds of technicians, engineers, and hobbyists, nationwide read and discuss electronics related questions each week. We welcome your participation en Sun, 26 May 2013 02:21:16 GMT vBulletin 60 http://techtalk.parts-express.com/images/misc/rss.png Techtalk Speaker Building, Audio, Video Discussion Forum - Tech Talk Forum http://techtalk.parts-express.com/ Math problem http://techtalk.parts-express.com/showthread.php?237719-Math-problem&goto=newpost Sun, 26 May 2013 02:01:44 GMT I've forgotten how to do a math equation and that is how to calculate the volume of a circle like a port or magnet on a speaker.I'm preety sure it invoves PI correct? ]]> Tech Talk Forum DannyG http://techtalk.parts-express.com/showthread.php?237719-Math-problem Suspension compliance for down-firing woofer? http://techtalk.parts-express.com/showthread.php?237718-Suspension-compliance-for-down-firing-woofer&goto=newpost Sat, 25 May 2013 23:41:17 GMT If I'm using a woofer in a downward-firing orientation, should I be looking for something with a specific suspension compliance? Or some other parameter? I've head that the cones/suspension can sag enough to cause problems. I suppose this could happen pretty quickly for drivers design for sealed enclosures with very compliant suspensions.

Any rules of thumb? ]]> Tech Talk Forum philthien http://techtalk.parts-express.com/showthread.php?237718-Suspension-compliance-for-down-firing-woofer Outriggers or bases for tower speaks http://techtalk.parts-express.com/showthread.php?237717-Outriggers-or-bases-for-tower-speaks&goto=newpost Sat, 25 May 2013 21:54:09 GMT I'm looking to get some ideas for a base or outrigger for my speakers. Would anyone care to share some of the pics of their designs.
I need some inspiration.

Rich ]]> Tech Talk Forum richard t http://techtalk.parts-express.com/showthread.php?237717-Outriggers-or-bases-for-tower-speaks <![CDATA[Need a 10-12" woofer for approx. 2 cubic foot box]]> http://techtalk.parts-express.com/showthread.php?237716-Need-a-10-12-quot-woofer-for-approx-2-cubic-foot-box&goto=newpost Sat, 25 May 2013 19:42:18 GMT I had originally contemplated building a single end-table sub w/ a Dayton SD315A-88 12" DVC driver with a passive crossover. Now that I got a half sheet of walnut plywood for only $15, I have enough materials for TWO subs. So I don't really have to have dual-coil drivers.

I'd like to get something that will give me about 89db/watt in an enclosure around 2 cubic feet. I'd like to keep the sensitivity there because I think it will be easiest for me to match to some satellites, seeing as I'm going with a passive crossover.

I'm happy if I get down to approx. 40-Hz. Anything lower than that is a bonus (I'll take it, but I don't want to compromise on sensitivity to get it).

I suppose I could still use the DVC drivers, and wire them in parallel in each cabinet. I like the price of those drivers ($60).

Any other suggestions? ]]> Tech Talk Forum philthien http://techtalk.parts-express.com/showthread.php?237716-Need-a-10-12-quot-woofer-for-approx-2-cubic-foot-box How much excursion should I see... http://techtalk.parts-express.com/showthread.php?237714-How-much-excursion-should-I-see&goto=newpost Sat, 25 May 2013 14:28:18 GMT Another thread about my Keiga 2.1 amp questions. Apologies.

I'm using Boston Acoustics Micro 110x speakers for satellites right now. They have a 3" woofer, and 1" or .75" dome tweeter.

I was playing the Lake Street Dive version of "I Want You Back" and noticed the little 3" woofers were moving quite a bit. More than I'd expect, as I had the variable crossover on the Keiga set at the highest point (about 200-Hz).

So I turned the sub amp level down all the way, so all I could hear was the satellites, and then started moving the crossover knob back and forth. I could hear no difference in the sound reproduced by the satellites. When I do this with the sub amp turned up, I can absolutely hear the difference.

So I think the variable low-pass has nothing to do with the signal going to the satellite amp built into the Keiga. I'm not sure if they have a fixed high-frequency filter or what.

Any thoughts?

Would I benefit by adding some 350-450 uf caps as bass blockers to the satellites? ]]> Tech Talk Forum philthien http://techtalk.parts-express.com/showthread.php?237714-How-much-excursion-should-I-see <![CDATA[End-table sub w/ 24" square paver top?]]> http://techtalk.parts-express.com/showthread.php?237713-End-table-sub-w-24-quot-square-paver-top&goto=newpost Sat, 25 May 2013 04:17:12 GMT Anyone ever make end-table subwoofers with 24" square pavers as the top? I'm thinking that a 1-1/2" thick 24" square paver, sitting on some thin rubber feet or rubber strips on top of the subwoofer cabinet, would have enough mass that it wouldn't move or vibrate.

I'm including a pic from SketchUp of the end table I have in mind.

I'd probably build two, and I'd have the satellite speakers clamped to the tops using clamps from Pedco:
http://www.amazon.com/UltraClamp-***...ds=pedco+clamp

You can find some neat pavers these days for $30 ish. Maybe I'd finish or seal them somehow.

Maybe I would look around for good deals on small (but thick) pieces of granite.

I'd use passive crossovers and power everything with an external amp, like a vintage Soundcraftsmen or Carver or NAD or something.
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]]> Tech Talk Forum philthien http://techtalk.parts-express.com/showthread.php?237713-End-table-sub-w-24-quot-square-paver-top Zobel http://techtalk.parts-express.com/showthread.php?237712-Zobel&goto=newpost Sat, 25 May 2013 03:05:56 GMT I want to ask someone who has knowledge with x-overs is it comman to have a big cap in a zobel,say 47uf ? I want to ask someone who has knowledge with x-overs is it comman to have a big cap in a zobel,say 47uf ? ]]> Tech Talk Forum DannyG http://techtalk.parts-express.com/showthread.php?237712-Zobel <![CDATA[Fierce Audio 10" flat pack subwoofer enclosure]]> http://techtalk.parts-express.com/showthread.php?237710-Fierce-Audio-10-quot-flat-pack-subwoofer-enclosure&goto=newpost Sat, 25 May 2013 00:22:33 GMT Saw this 10" flat pack subwoofer enclosure on sale at BB for $12.99 free shipping.

http://www.dealsofamerica.com/jump/b...18&sku=9854731 ]]> Tech Talk Forum ntt http://techtalk.parts-express.com/showthread.php?237710-Fierce-Audio-10-quot-flat-pack-subwoofer-enclosure Wondering if this will work ok. AR 8 inch in TL. http://techtalk.parts-express.com/showthread.php?237709-Wondering-if-this-will-work-ok-AR-8-inch-in-TL&goto=newpost Fri, 24 May 2013 23:38:55 GMT Has anyone ever used these and would they be suitable being used in a TL sub. I have no TS parameters for them. Attachment 36629... Has anyone ever used these and would they be suitable being used in a TL sub. I have no TS parameters for them.
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I can't afford a better driver right now and I was hoping these would work as a temp. solution to get the subs up and running. They will be crossed over at 99hz.
If you guys don't feel they would work well enough, I'll just have to use them in another build. For 12 bucks a pop, I'm sure I can put them to good use elsewhere if I have to.

Thanks in advance.
Rich
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]]> Tech Talk Forum richard t http://techtalk.parts-express.com/showthread.php?237709-Wondering-if-this-will-work-ok-AR-8-inch-in-TL Seas ER18RXN cabinet recommendations http://techtalk.parts-express.com/showthread.php?237708-Seas-ER18RXN-cabinet-recommendations&goto=newpost Fri, 24 May 2013 23:18:46 GMT I may have posted this on the wrong forum - I apologise. http://www.madisoundspeakerstore.com...r-cone-woofer/ what is the most practical,... I may have posted this on the wrong forum - I apologise.


http://www.madisoundspeakerstore.com...r-cone-woofer/

what is the most practical, or largest, cabinet to maximize bass for this woofer?

And can the port be on the front of the cabinet to increase bass? Or would it just muddy up the sound?

charles ]]> Tech Talk Forum airtime http://techtalk.parts-express.com/showthread.php?237708-Seas-ER18RXN-cabinet-recommendations Can I replace an air inductor with .1 difference? http://techtalk.parts-express.com/showthread.php?237706-Can-I-replace-an-air-inductor-with-1-difference&goto=newpost Fri, 24 May 2013 22:26:02 GMT With the help of peepaj, this user suggested some components for a crossover. However one of the parts is back ordered until late next month. Peepaj... With the help of peepaj, this user suggested some components for a crossover. However one of the parts is back ordered until late next month. Peepaj suggests Jantzen 1.4mh 18awg. This has .65 ohms of resistance. The 1.3mh version of this is .61 and the 1.5mh is .67 Would any of this cause problems?

Also he suggests 0.05 air inductor of 18 awg. Jantzen and PE are out of stock on these as well. ERSE has two in stock but would mix matching different brands like that cause any concern? ]]> Tech Talk Forum xsundown http://techtalk.parts-express.com/showthread.php?237706-Can-I-replace-an-air-inductor-with-1-difference And so it begins http://techtalk.parts-express.com/showthread.php?237705-And-so-it-begins&goto=newpost Fri, 24 May 2013 22:16:36 GMT Starting a new project always makes for a good day. :) Image: http://s7.postimg.org/jtlwk4asr/New_Project.jpg :drums: :D Starting a new project always makes for a good day. :)

:drums: :D
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]]> Tech Talk Forum DeeEyeWhy http://techtalk.parts-express.com/showthread.php?237705-And-so-it-begins OT: Whats up wth this?? http://techtalk.parts-express.com/showthread.php?237704-OT-Whats-up-wth-this&goto=newpost Fri, 24 May 2013 20:54:00 GMT Was looking at the diysound group subwoofer page and what looks like a mistake,,,there are some sub kits advertised for $1.00..whats up with that? ... Was looking at the diysound group subwoofer page and what looks like a mistake,,,there are some sub kits advertised for $1.00..whats up with that?

http://www.diysoundgroup.com/subwoof...ofer-kits.html ]]> Tech Talk Forum Kingo http://techtalk.parts-express.com/showthread.php?237704-OT-Whats-up-wth-this <![CDATA[Any crossover posted for Vifa 3 1/2" TC9FD-18-08 and Dayton 5/8" ND16FA-6]]> http://techtalk.parts-express.com/showthread.php?237703-Any-crossover-posted-for-Vifa-3-1-2-quot-TC9FD-18-08-and-Dayton-5-8-quot-ND16FA-6&goto=newpost Fri, 24 May 2013 18:53:45 GMT Have a pair of these that did not work out for my original project.... Attachment 36619... Have a pair of these that did not work out for my original project....
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http://www.parts-express.com/pe/show...umber=264-1062
To my ear, they are lacking a bit of "effortless" high end. Sorry for the subjective description.
Has anyone paired them in a miniature two way with these, for instance...
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http://www.parts-express.com/pe/show...number=275-025

Still have not learned crossover software. Just checking to see if anyone else has info on a two way with the 3 1/2 Viva or could suggest a quick and easy crossover for the Dayton 5/8 or other in a sealed box.

Thanks
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]]> Tech Talk Forum frascati http://techtalk.parts-express.com/showthread.php?237703-Any-crossover-posted-for-Vifa-3-1-2-quot-TC9FD-18-08-and-Dayton-5-8-quot-ND16FA-6 OT : Squaring up a tablesaw http://techtalk.parts-express.com/showthread.php?237701-OT-Squaring-up-a-tablesaw&goto=newpost Fri, 24 May 2013 13:59:55 GMT My consumer grade 10" craftsman table saw has been giving me problems for a while now... blade has been pinching against the fence near the back side and burning the wood and causing inconsistencies. I finally read up on how to fix the problem and sorted it out last weekend. Only problem is that it seems the riving knife did not maintain alignment with the blade when i adjusted it. It's funny that the instruction manual explains how to align the knife by using washers, but because it ships with no washer on the "left" side, there is nothing to remove if you need to shift it "left". After going a little beyond the instruction manual and removing the whole mounting assembly i found some thin aluminum (?) spacer pads. I removed them to shift the bracket in the correct direction, but it's still a bit out of whack.

This weekend i will put one of those alluminum pads back in place because i think i shifted things a bit too far, but it seems almost like there's a weird angle between the knife relative to the blade now, even though the blade seems true with the slots on the table.

The blade is not original but i think it's within specs for kerf width - i should get some calipers and double check that.

Curious if trying to keep one of these low end saws running true is a losing battle. It's about 5 years old and has seen a fair amount of use. Including a 5.1 system build of curved cabinets all made via kerf-cut-bending.... i never want to see that much saw dust again :p

thanks ]]> Tech Talk Forum lowpolyjoe http://techtalk.parts-express.com/showthread.php?237701-OT-Squaring-up-a-tablesaw