AK Design Collaborative - Insignia-Class Economy Speakers (a.k.a Indignia)

[Robie]

Maybe we track down the Tang Band rep.

I'm looking at Gordon's suggestion, and the price is certainly good.

How's that one going to do in our little box?

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-300

Sensitivity and Xmax are on the low side, looks like, by comparison....

Now that GordonW has weighed in, our best guys are all over this project. As Snade observed, "This is AK at its best."

Sorry for the interruption, but have we decided what "our little box" is yet, or is that a reference to agreed upon cabinet volume? As they say on talk radio, "I'll take my answer off the air."

Carry on, Gentlemen.

 

[lissjw]

need clarification

I'm new here and not technically savvy so here is my question. Are you guys designing a speaker that could be purchased and built buy someone like me?
If so I'm in.

 

[YamahaFreak]

I'm new here and not technically savvy so here is my question. Are you guys designing a speaker that could be purchased and built buy someone like me?
If so I'm in.

I'm kinda in the same boat. I'd like to build myself a set, but the costs involved in building the cabinets would be prohibitive for me.

 

[dnewma04]

there will be a couple of options, you choose the cabinet, as long as it's .25 cu ft (those more skilled don't need to comform to this restriction) or just buy the cabinets off of partsexpress.com

 

[lissjw]

Cabinets

So cabinet design doesn't have much to do with the sound?

I could play around in the garage with templates provided, and eventually get good cabinets, then I could decide on the finish. The inards of the speakers are out of my realm as well as crossovers. If you guys are going for sweet sound I belive I could go a little over your target price for some Kick a-- speakers that I put together.

 

[Zilch]

Now that GordonW has weighed in, our best guys are all over this project. As Snade observed, "This is AK at its best."

Sorry for the interruption, but have we decided what "our little box" is yet, or is that a reference to agreed upon cabinet volume?

Yes, basically, for a start, consistent with "Insignia-class." We're evaluating different drivers that might work in the smallest PE prebuilt cab, with that baffle size and cabinet volume.

I'm new here and not technically savvy so here is my question. Are you guys designing a speaker that could be purchased and built buy someone like me? If so I'm in.

Yes.

I'm kinda in the same boat. I'd like to build myself a set, but the costs involved in building the cabinets would be prohibitive for me.

We haven't gotten to the "How to" of the cabinet yet. I'll be posting some pics and dimensions as soon as they arrive, maybe late this week, or early next....

 

[RayW]

Like Dave said, the "guts" will be defined as we traverse this thread. The enclosure will be up to the end user. You can make a simple butted MDF box (my preferred method ), I'll probably do something with a chunk of Sonotube since I have some laying around, Robie was talking about slitting a piece out of a cyllinder and putting a baffle on the front, or as Zilch pointed out (and Dave said again) you can buy them prebuilt from PE. If you feel like going high zoot then you can do lock mitre joints out of solid mahogany. The idea is that the drivers and crossovers will be agreed upon here and then we'll have several things going for us.

1) some folks who don't know anything about speaker desiging/building can learn along the course of the thread

2) folks who want to build their own but don't care about how the design process works can read the last page and build from plans

3) a whole group of us can have a common "reference" speaker to compare others to so statements like "it has more bass than AK1" make more sense (note: AK1 was the first thing that popped in my head, I'll let more artistic types come up with a cool name)

d) we get to hang out and talk speakers and what's cooler than that?

On the cabinet affecting sound...It can make a world of difference and that's part of the fun of playing around. The single biggest factor is enclosure volume. That will be nailed down. After that, the stiffness of the walls, internal damping, internal shape, materials used will all have an effect. We'll see what shakes out. In general if we all make them the right size and reasonably rigid then we'll all get a very similar sound.

Ray

 

[RayW]

Dave re: the PE tweeter - have you heard it? The design looks cool but I'm not sure about the hump around 6-10k. Could make them kind of hot but I've never heard. Personally, without hearing, I'd rather spend the extra $4 and get the Vifa D27TG-05 with a very flat curve. It's ubiquitous to DIY designs, but for a reason. If you have experience with it, share it. Or get one to play with.

Beginner notes: I've been spitting out a bunch of numbers about different drivers in our box design. These are merely simulations run using software to predict what each driver will do in said box. I use Harris Tech Bass Box 6 mostly because I've been using it for ...coughcough...years so I'm really familiar with it. I find it fairly accurate and I can have a design cranked out in a couple of minutes. Programs like this use the Thiele-Small parameters of the driver, which are mostly provided by fine vendors like PE.

The numbers that I keep referencing are f3, f6, and f10. These are the frequencies at which the bass response is down by 3dB, 6dB, and 10dB when referenced to the average across the drivers passband. The f3 tells you when the bass starts to roll off, f6 is a good indicator of the low end of usable bass in open air, f10 can be called a bit of a cheat but it is often used as the low end of usable bass in-room counting on a certain amount of room gain.

Make sense?

Ray

 

[YamahaFreak]

Dave re: the PE tweeter - have you heard it? The design looks cool but I'm not sure about the hump around 6-10k. Could make them kind of hot but I've never heard. Personally, without hearing, I'd rather spend the extra $4 and get the Vifa D27TG-05 with a very flat curve. It's ubiquitous to DIY designs, but for a reason. If you have experience with it, share it. Or get one to play with.

Beginner notes: I've been spitting out a bunch of numbers about different drivers in our box design. These are merely simulations run using software to predict what each driver will do in said box. I use Harris Tech Bass Box 6 mostly because I've been using it for ...coughcough...years so I'm really familiar with it. I find it fairly accurate and I can have a design cranked out in a couple of minutes. Programs like this use the Thiele-Small parameters of the driver, which are mostly provided by fine vendors like PE.

The numbers that I keep referencing are f3, f6, and f10. These are the frequencies at which the bass response is down by 3dB, 6dB, and 10dB when referenced to the average across the drivers passband. The f3 tells you when the bass starts to roll off, f6 is a good indicator of the low end of usable bass in open air, f10 can be called a bit of a cheat but it is often used as the low end of usable bass in-room counting on a certain amount of room gain.

Make sense?

Ray

Miraculously, yes!

 

[dnewma04]

Which PE tweeter, the modded 275-070, the stock 275-070 or the new 1-1/8" with the small mounting flange? If so, I have experience with stock 275-070. I liked it in budget applications where a lower crossover point was required where my prior favorite budget tweeter (the Audax TM025F1) couldn't be made to work well. The Audax with a 2500hz 2nd order crossover or preferably 3khz was a better tweeter, there is no doubt in my mind. It measured significantly flatter than the 275-070 and combined elements of the typical soft dome tweeters with the freq extension associated with hard domes (not that I buy into this idea). Speaking of metal dome tweeters, I do see the TM025F7 is still available. I'd hesistate to drop it from the possibilities mix as it performed very similarly to the F1 through much of it's operating range.

The 275-070 does have some brightness issues and it's been a while since i've worked with them, but I recall with a little tweaking of the crossovers, I was able to curb that to a great extent.

I could never complain about that D27TG-05 being used. I haven't used it myself but have heard it mroe than once in other DIY designs and i've come away impressed. There was a peerless tweeter that I really liked but I can't seem to come up with the model number right now, but it's a moot point as it's no longer part of the conensed product lineup.

On a side note, i'd love to see some curves for some of the cheap goldwood products. I'm embarrassed to admit that I have used the 290-309 to surprisingly good effect in a couple of budget car audio setups. Actually i used the 4 ohm version an dlinked the 8 ohm version. Besides an ultra cheap basket, they aren't bad speakers and sound far better than they should.

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=290-309

 

[RayW]

On a side note, i'd love to see some curves for some of the cheap goldwood products. I'm embarrassed to admit that I have used the 290-309 to surprisingly good effect in a couple of budget car audio setups. Actually i used the 4 ohm version an dlinked the 8 ohm version. Besides an ultra cheap basket, they aren't bad speakers and sound far better than they should.

I thought about going that way but I don't know much about them. I've never heard them and PE doesn't seem to do curves on them. Back at my former employer we made a bunch of Pyramid speakers. They were always getting a bad slant simply because they were Pyramid. Some of them weren't bad. I always wanted to do up a whole car system with their drivers just to show that it could be done. I would imagine we could do the same with the Goldwood stuff. Just have to sample them until we find the right one.

Unfortunately, I'm pretty lazy and I'd rather go with a known entity for this project. But if somebody wants to go that direction I'll go with ya.

Oh yeah Dave, Zilch, Gordon, and anybody else who's been this route before, if I say something stupid in my little "beginner comment" posts call me on it. We all make mistakes and I'm the guy bringing up the average.

Ray

 

[lissjw]

Beginner notes: I've been spitting out a bunch of numbers about different drivers in our box design. These are merely simulations run using software to predict what each driver will do in said box. I use Harris Tech Bass Box 6 mostly because I've been using it for ...coughcough...years so I'm really familiar with it. I find it fairly accurate and I can have a design cranked out in a couple of minutes. Programs like this use the Thiele-Small parameters of the driver, which are mostly provided by fine vendors like PE.

The numbers that I keep referencing are f3, f6, and f10. These are the frequencies at which the bass response is down by 3dB, 6dB, and 10dB when referenced to the average across the drivers passband. The f3 tells you when the bass starts to roll off, f6 is a good indicator of the low end of usable bass in open air, f10 can be called a bit of a cheat but it is often used as the low end of usable bass in-room counting on a certain amount of room gain.

Make sense?

Ray

I think I need to go back and read your other posts again, as my eyes just glazed up as I read those numbers. I think I have a hint of it, but its late. I'll check again tomorrow.

Thanks for taking the time to explain this. From the short time I have been lurking here it appears that this is a group of people who know what they are talking about. I feel like a 5 year old at college.

 

[Fedallah]

Madisound still has the Loudspeaker Design Cookbook on sale. Great general reading and reference for any audiophool. Just a quick once-through and you should be able to understand most/all of the numbers being bandied about in this thread. As for contributing intelligently, well, that requires a bit more investment in equipment, software, and stuff to test. Oh, and time.

Sorry to worsen the SNR in here. Keep it coming, gentlemen...

 

[Zilch]

I'm answering Robie's question above with "Insignia-class," and saying to myself, "HEY, what size IS Insignia?"

So, I go to the website, and it says 18-3/10" high by 12-1/5" wide, which would seem to be way wrong.

Would someone who has Insignias measure H, W, & D for us and post the actual size here, please, without the grille? :yes:

Madisound still has the Loudspeaker Design Cookbook on sale. Great general reading and reference for any audiophool.

That edition features design details of his Studio Monitor kit, very similar to what we're building here. His are 0.28 cuft. and ours 0.25 cuft. -- "Mini-Monitors," I'd call them.... :thmbsp:

 

[jimbofish]

For a newbee to speaker design, would there be any reason to get the 7th edition, or would the 6th edition be more than enough. At that price I would go for it, full price... maybe not.

 

[Zilch]

For a newbee to speaker design, would there be any reason to get the 7th edition, or would the 6th edition be more than enough. At that price I would go for it, full price... maybe not.

It's fine. The basics are all there.... :guitar:

 

[YamahaFreak]

The Insignias are...

13 3/8 inches tall, 10 1/2 inches deep from the back edge to the front baffle edge, 8 3/4 inches wide at the front, and roughly 1 3/4 inches wide at their narrowest point, the back. :yes:

Would someone who has Insignias measure H, W, & D for us and post the actual size here, please, without the grille? :yes:

 

[Zilch]

Thank you, YF. :thmbsp:

Do we want to step up to PE's 0.38 cuft., which would be more comparable to Insignia, externally, now that we've had a look at achievable bass performance in 0.25 cuft.?

 

[YamahaFreak]

Thank you, YF. :thmbsp:

Not a problem. I'm happy to be helping this project move along. :thmbsp:

 

[Robie]

Thank you, YF. :thmbsp:

Do we want to step up to PE's 0.38 cuft., which would be more comparable to Insignia, externally, now that we've had a look at achievable bass performance in 0.25 cuft.?

Again, not sure this helps but does it make sense to go with the volume that provides the biggest bang for the buck? In other words, if the bigger cabinet volume makes cheaper drivers available that should be the route to go. Probably a trade-off though.

Ray and Zilch, you both have a knack for explaining things so that even this resident of the lower end of the bell curve (me) can understand. Thanks for taking the time. As for the DIY aspect, the hook has been set here.