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Similost's Speaker Build - Watch this space for lots of laughs.

Thanks David, and all the rest..

I sure hope this pans out, and I don't get bored with the project before I get it done.. but I can't imagine that happeneing for the simple fact I just GOTTA hear what everyone is raving about with the guides and the sound.. plus from just plugging up these drivers and listening to them laying on the floor.. wow.. they should be pretty fantastic sounding...

I got everything ordered up last night for the crossovers, but one of the inductors is on back order until the 29th. I hope...

I got so much crap I need to get done around the house before I can really dive in heavy, but I do hope to get into my garage on Saturday and Sunday to try and dig out my table saw, and get started on the baffles and backs for the cabs. I hope to have everything mounted up and usable by next weekend...

I hope... man do I hope... It's killing me having these Lambda's just laying there and not being able to see what they really do...
 
squirrelnest said:
When you get your speakers up and running........turn up the volume so I can hear them play from by house or at least feel the base!
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You're more than welcome to come over and give them a listen.. bring what ya wanna hear.. I'm sure after I get them done, there will be a few of the guys that will be dropping by to check them out...

Sure would be nice if I could get them done for the 30th at Rygens.... :scratch2:
 
similost said:
LOL.. I sure didn't see that...

So... I guess that if these drivers are at the very least they sell 430g, then the only way I could get them lighter is to start drilling lightly into the back of the masonite to lighten it more.

If I get it lighter, how would I know what the free air resonance is to input that. How can I also tell how much the piston weighs? Probably only by taking it out of the frame and weighing it? I sure don't want to do that..

So basically what I am trying to get at here.. is from what I am seeing even with the numbers I'm using, these drivers are very usable in this box? I just need to work on the tuning point...
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I'll bet that 430 grams will work fine. I like to have 'em tuned low... it seems to work well with "room gain", when the speaker is close to a wall. With the passive on the back, it'll "couple" with the wall behind it very well... that seems to "cheat" a bit more low bass out of them. Could balance out nice.

Try it at 430 grams... I bet you like it.

Regards,
Gordon.
 
If my PR's are 430g, then that's what I'm going with, but if they are the 700 or even 1400g, then all I could do is drill weight from the back side.. The problem is, I have no way to find out what the weight is without taking the thing apart to weigh it..

I really wish they would at least stick a sticker on their PR's with the part number so you could have a clue what you're working with...

Is there any way I could measure deflection in some way to get an idea of the weight maybe? I don't know.. I'm shooting in the dark here for ideas..

BTW.. yep, they will be close to a wall.. with the PR pointing at the wall..
 
similost said:
If my PR's are 430g, then that's what I'm going with, but if they are the 700 or even 1400g, then all I could do is drill weight from the back side.. The problem is, I have no way to find out what the weight is without taking the thing apart to weigh it..
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If you have a starting weight, then just weigh the whole thing. When you remove some you'll know all the weight you're removing comes from the moving mass so you'll know how much is left.

I really wish they would at least stick a sticker on their PR's with the part number so you could have a clue what you're working with...
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Wait a sec...you're getting a PR and you don't know the starting value? If that's the case then your questions make more sense. :D

Is there any way I could measure deflection in some way to get an idea of the weight maybe? I don't know.. I'm shooting in the dark here for ideas..
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If you have a signal generator and a similar sized active speaker you can estimate Fs and work backwards if you have some other parameters but it's far from precise. Put them face to face with a little gap. Start running the frequency up and you'll see the PR moving. Watch for the maximum movement and that will be your Fs. You can make a little jig with a straw to measure maximum excursion off the back fo the cone to help out.
 
Right Ray...

I bought these from an individual, not from AE. Theses were bought for a project, and the guy never went that route, so he sold me these.

The TD15M's and these PR15's were bought when John was making them, long before AE took over making the Lambda's..

SO, I have NO CLUE what the weight of the piston is on them... but I was told they were sold as a set to work in 4 to 5cuft boxes.. which I'm at 4.5, but will be reducing that some with bracing..
 
Gotcha. In that case, I'd say build it up as-is. Then measure the impedance and you'll be able to figure out the tuning frequency from there. You can add or remove weight at that point and season to taste.

And do you mean when Nick was making the Lambdas? John is the guy at AE, Nick McKinney is the one who started Lambda back in the old days.
 
If you worked as much on the speakers as you post,
you would be finished!! :yes:

Oooops! Did I say that??







I really hope you take that as a joke!
 
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I think Simi might be posting from work while the workload is light. They might frown on him wheeling a tablesaw into the IT department. 'Course you never know... :D
 
Hmmm? :scratch2: posting from work!


That is where I get my best ideas for my home projects too!
 
RayW said:
Gotcha. In that case, I'd say build it up as-is. Then measure the impedance and you'll be able to figure out the tuning frequency from there. You can add or remove weight at that point and season to taste.

And do you mean when Nick was making the Lambdas? John is the guy at AE, Nick McKinney is the one who started Lambda back in the old days.
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Sorry, yes, that's it.. Nick... I was thinking backwards.. THat's the reason the plug on mine is black, along with the edges of the frame arms not being ground down through the power coat..
 
LOL.. Yeah.. I'm kinda like a fireman at work.. I just wait until they need something then rush to piss on the fire.. SO, I only wish I could work on them while I was sitting there in my office.. At least I can figure numbers that don't mean much to me...
 
Now that you started a thread we need to see results, the pressure is on. :D

Are you going to run the stock grills? If so you'll need to mount everything from the back side.

To answer your question mine are crossed over at 1,200 hz.
 
Yes, I'll be leaving the grill in place. I will run the woofer on the back side of the baffle, and recess the horn flush on the front side. It's also the only way I will be able to get them both to fit in the baffle. I'll also add a brace between the horn and woofer on the rear.. I think. I think I'll have about an inch between the woofer frame, and the cutout for the horn. This should help support all the weight and keep the baffle from cracking.

I'm going to mount the radiator on the outside of the rear panel to keep from taking up as much internal volume.

Thanks for letting me know about the 1200 cross.. I am kind of wondering if mine will be better at 1200, or 1600.. but guess it's too late now since I spent all the jack on the crossover parts for a 1200 cross...

I'll be taking lots of pictures, and will try and get these done as fast as possible just so everyone isn't sitting around waiting so much..
 
James, while you have the cabinets apart I'd sand them down lightly with some 200 grit, or OOOO steel wool if you prefer, and then apply 3+ coats of tung oil. I think you'll like the results. Here's the top of mine after applying 3 coats.

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hhhmm.. interesting idea.. I had just been treating them with Howard's wax... Those do look pretty nice..
 
Are they baby butt smooth? I use Howard's on speakers I don't want to put much time into. For speakers I'm keeping a light refinish will make a lasting difference. You don't want to remove all the stain just make them look consistent and smooth. They are worth spending a hours worth of elbow grease on. :yes:
 
4.5 cu ft tuned to about 35-38hz is about where you want to be with the TD15M, it's really a little on the shy side, ideally you'd want to be in the 6 cu ft range.
 
They aren't baby butt.. but they are really smooth, and the finish is perfect on them. Other than the banged up corners on the rear at the bottom from being tipped back, they are perfect.. no scratches, no dings, no rings or stains..

Kind of what I had thought Dave looking at the numbers I was coming up with. I figured it would probably lower that max excursion bump below 100hz.. but I got what I got for a box... I'm hoping like hell it works..
 
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