silk purse from sows ear contest?

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The original method was to choose europe or north american and price all of your drivers from vendors on that side of the pond, no matter where you actually bought them from.

For example, say there is a PE driver for $5 with $6 shipping for me. I claim $5 as the price, even if I bought it at the local flea market for $7 as that saved me $4 in shipping. I use the advertised price from how ever many vendors I want, no matter where I buy it from. The only rule was keep it all on the same side of the atlantic. I can see that Austrilia is another ocean hop in regards to shipping. I think as long as you follow the spirit of the law, not the letter of the law you will be fine. Just use a well reasoned explanation for driver costs locally, and abroad, and people should be able to understand. No matter what we do as a collective group it cannot be 100% completely fair as exchange rates change over time, availability locally is very different, plenty of variables are not within our complete control, so why bother trying, just enjoy the challenge.
 
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Damn. Was supposed to be a simple contest. A higher price was set for Europe because of typical prices. Then international relations got in the way. :(

Do what you want. If it looks like gaming the rules, prepare to be called out for it.
Limit per speaker down under is $58 AUS if you buy them there. Isn't that enough?
 
I thought the fun and thought of all of this was to make a silk purse from a sows ear! Some of the drivers folks are looking at are not sows ear quality! ;)


I squeal when I gotta pay $15 for a driver! Com'on, guys.. Make this fun and produce a diamond from a piece of coal. Lower yourself to a car speaker! Show your talent instead of using a predictable driver. Crawl out of the box!
 
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Thanks Tony. From your price list it looks like $58 might be too low a budget in Australia.
Maybe $65?

Well the posted comparisons are probably fairly indicative. I just chose some drivers in the lower price ranges that are available in both the US and at wagner, and the average differential when multiplied by $30 is $65 so that does seem reasonable for an AU $ limit.

I guess if TMM wanted to mix and match purchasing from OS and AU then for stuff purchased from the US it would need to be multiplied by 2.17 to get the AU$ value, and if in Euros then multiply by 1.76.

I think in general that should hold. Choose one currency and everything has to be relative to that. It would not be fair otherwise.

Tony.
 
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What's with the low end of the MCM 6.5 and 8" drivers? When I try and sim them to work out the box that the measurement was taken in, the closest seems to be about 8L sealed which seems rather crazy. The rolloff is appaling. I gave up on the 8" and tried the 6.5"

I got it doing very well from 100Hz up crossed at 3Khz to one of the new dayton tweeters, but It's really bad below 100Hz. Has anyone used them, and are they better in the low end than the published measurements would suggest?

Not bad for $14.50 US worth of drivers though!

Note that the low freq response here has been adjusted to reflect a 20L BR enclosure tuned to 40Hz. I've been playing around with subtracting the sealed enclosure rollof from the manufacturers curve and then adding back in the rolloff that the alignment I choose will be. Works great for peerless drivers which model an almost exact fit to the factory response in sealed 20L enclosure (which a lot of manufacturers use) but the MCM's I can't get a good match (no matter what I try). Maybe they really are using an 8L sealed enclosure, if they were then the adjusted response would look a lot better (I went with 20L sealed for the subtraction model).

By the way the MCM driver here is this one http://www.newark.com/mcm-audio-sel...cfm=true&ddkey=http:en-US/Element14_US/search I can actually get these here in Aus from element14 price $12.93 (ex tax) so adding tax it pretty much comes out like the others, at 2.14 multiplier.

edit: I may blow the budget on the inductors to make this work though!
edit2: tweeter is this one Dayton Audio TD20F-4 3/4" Soft Dome Neodymium Tweeter 4 Ohm
crossover 4th order bessel acoustic at 3Khz

I think I can also get the dayton from wagner, so I'm tempted to give it a go (would probably just make one and if it turned out ok get a second set of drivers to make a pair).

Tony.
 

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Just another Moderator
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I'm using vituix cad for the sim (fantastic program!), but the display is in speaker workshop. I've got to head for bed (it's nearly midnight) but I can do a walk through of the steps I went through if you like :) I might do it for the peerless driver though because the measurements are more reliable!

Almost everything was done in vituix cad, the spl traces, the baffle diffraction modeling, the box modeling and the crossover design. The only bit that was done in speaker workshop was the manipulations to remove the sealed response and then replace with the vented response (should also be possible to do in vituix cad but I haven't worked out how to use the calculator tool yet.

Picture of the whole lot in vituix cad. I used -15mm for tweeter offset.

Tony.
 

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Maybe when our timezones overlap you could do a screen share presentation / tutorial? I think youtube has a live video component, you could schedule it and open it up to the forum even! Otherwise, google hangouts is/was another easy free way to screen share, not sure if that feature is there in the freebie version now tho.
 
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I could possibly do something on youtube. My daughter does screen capture things all the time so I'm sure she could show me how ;) I just realised though that the above has a mistake in it. I forgot to put the baffle diffraction in for the tweeter, it probably won't make too much difference but will make it a bit less smooth.

Tony.
 
The original method was to choose europe or north american and price all of your drivers from vendors on that side of the pond, no matter where you actually bought them from.

For example, say there is a PE driver for $5 with $6 shipping for me. I claim $5 as the price, even if I bought it at the local flea market for $7 as that saved me $4 in shipping. I use the advertised price from how ever many vendors I want, no matter where I buy it from. The only rule was keep it all on the same side of the atlantic. I can see that Austrilia is another ocean hop in regards to shipping. I think as long as you follow the spirit of the law, not the letter of the law you will be fine. Just use a well reasoned explanation for driver costs locally, and abroad, and people should be able to understand. No matter what we do as a collective group it cannot be 100% completely fair as exchange rates change over time, availability locally is very different, plenty of variables are not within our complete control, so why bother trying, just enjoy the challenge.
Absolutely agreed. I'm not trying to find an loophole in the 'rules', my issue was that I was shot down for suggesting that someone outside of the US/EU like myself might include a collection of parts in a design that while all readily available locally, might be difficult for someone in EU or US to replicate because some parts may be more 'EU market specific' while others may be more 'US market specific'. It may be impossible to find EU or US prices for everything since some parts may not be obtainable there or may attract very noncompetitive pricing. The pricing in Australia is somewhat all over the place because the market is so niche. It's difficult to define a "speaker driver index". The most obvious solution is just to allow everyone to pick prices from wherever they want regardless of where they live. That way everyone is on an even playing field.
The impression I got was that by using prices from multiple locations this was considered 'cheating' and instead have to alter my purchasing to emulate living in EU or US, narrowing the choice of locally available parts. I'm speechless that I was given such a hostile response given that this is supposed to be for fun and there is nothing to gain from 'winning' if it can even be decided that there is a winner (i'm doubtful).
 
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