Iron Driver Overall Best Sounding Speaker: Design Details

[ryanbouma]

Matt and I (monoiz15) were pleased to have been voted as the overall best sounding at the Iron Driver event.

Here are the design details. If there are any technical questions, I'd happily answer. If there are any construction or sound quality questions, hopefully Matt or others from the day can tell you their thoughts.

It's an MTM design using the iron driver (Peerless 830656) and the Vifa XT25BG60-04 (found here: http://www.parts-express.com/pe/show...umber=264-1012 )

Here is the model.



Here is my final measured response.



Here is the cross over.



Here is the BOM



Here is a link to the detailed measurements by R-Carpenter: http://techtalk.parts-express.com/sh...75#post1858775

I'll ping Matt to step in here and post box and port dimensions as I forget. He handled more of that. According to him the bass is "In my bedroom the bass is huge and I actually don't think a sub would really help at all other than extending the bass a tad lower at the expense of trying to integrate it properly. Simply not worth it to be honest". Sound good to me ;)

The design philosophy was to extract as much as we could out of the iron driver whilst not going 3-way and spend the extra money on a good tweeter. MTM it was. A quality tweeter from PE made xo design a snap. These drivers are so well behaved it made life very easy.

Thanks for looking.

[jclin4]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

XO network of 5 components? Very impressive!

Looks like you nailed it in terms of where the tweeter needed to be crossed. Congrats and accolades well-deserved!

[mzisserson]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

lol at the tweeter drawing...


Anyway, again, great job. Simple, effective, and certainly got the job done.

[ryanbouma]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

lol at the tweeter drawing...

Ha, it looks like a c0ck. If I drew it like a ring radiator it would have looked like a t!t. :D

[theLinks]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

Thanks for the laugh!
Tim

[ontariomaximus]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

Outstanding crossover. Lemme guess - you tuned it by ear and didn't let the computer tell what should sound good.

[johnnyrichards]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

As a fan of simple networks, I can appreciate this. As a fan of *appropriate* networks, I can appreciate whatever it takes to hit whatever target you are shooting for. Well done, Ryan and Matt.

[ryanbouma]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

Thanks all.

Ontario max. In all honesty, I started by measuring the drivers. Then modeling 4 or 5 possibilities. Then gave them all a hard look and weeded out a couple. I was able to do that based on the cost limitation of the competition and the measurements. Then gave, I think 3 a hard listen. Weeded it down to two. Passed those on to Matt. He then picked this. I confirmed I thought it was best. I do have one I think might be 0.003% better but it costs a bit more.

[bkeane1259]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

lol at the tweeter drawing...

Bwahahahahaha

[WernerM]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

lol at the tweeter drawing...

Funny that was my first thought too... Anyway, very impressive to walk away with the overall best honors with such a small crossover network.

[monoiz15]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

Here's the box

[mzisserson]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

Funny that was my first thought too... Anyway, very impressive to walk away with the overall best honors with such a small crossover network.

As designs get published, you may find all of them were more simple than you think. The 830656 can practically run full range with little issue. It is a very well behaved driver. Cross it high enough to an appropriate tweeter and as you can see attention to detail can yield a good result.

[ernperkins]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

lol at the tweeter drawing...

Maybe the tweeter is the real iron driver in this case :D

Anyway - congrats on an elegant design..

[ryanbouma]

Re: Iron Driver Overall Best Sounding Speaker: Design Details

I had someone ask about an MT design, maybe for surrounds or something. The value is a little lost on the MT, but it is 8ohm this way and a touch cheaper. Anyways, just a simulation, never tried it.



The cross over is 1.8mH and 10uF on the woofer. Tweeter is the same except instead of 1.5ohm it's 5ohms followed by 6ohms in parallel. I'll draw it up sometime if I don't forget. It's as expected. Double the choke, half the cap on the woofer. With a change in tweeter padding.

The same person also asked about subbing the xt25tg30-04 and I can't see why that would be a problem. If someone with experience with both can say otherwise, please let me know. But their impedance and FR look nearly identical.

[Geoff Millar]

Hello from Australia

You have probably got tired of answering these questions, but could the VIFA BC25TG15 be substituted for the XT 25? I already have a pair of the BC25s and the XT series are very expansive to buy here

From the spec sheets, the responses and resistance look very similar, and I love the simple crossover.

The "ratio" measurement is different, and the FS is double the XT but the FS still looks as if it would work ok with your crossover point (ie the crossover frequency is more than double, which is my very rough understanding of these things).

Thank you

Geoff