Before Thunderchild

[dog1]

Pictures by vertical1dog - PhotobucketAfter going back an forth in another thread and showing my inept reasoning, I have decided to begin anew.

Before Duke introduced his Thunderchild line of bass speakers, he and I were working on a lightweight modular bass system that incorporates the fine Eminence 3012LF in two cabiets, with one also having a mid driver and wave guide.

Duke and I lost contact nearly two years ago, through no fault of his, and I finished the cabs on my own. The result was good enough that I have since sold everything else I own (GB NeoX 212T, Aguilar GS 212 & Peavey Pro 410) and only kept the cabs designed by Duke, and a 112 I built with a fine JBL 2204 that he helped me with porting.

I have never tried his Thunderchild cab, but would like to. But, it is hard for me to believe that it can compare with the original version he desiged, and I built.

The sound of this stack is unbelieveable. Solid and deep, but without booms or farts. Even though the E string is more powerful then the others, it is not overwhelming and the other strings are almost equally deep and solid.

Anyway, we all know that everyone has opinions, and opinions are like xxxxxxxx. Also, I am no tech guy. Just a simple bass player. Even though I have played for 45 years, my opinion is no better then anyone else. But for me, I'm not looking for the perfect cabs because I have them already. Light, powerful, and able to handle 900 watts.

Thanks Duke. I can never repay.
[IMG][IMG]s727.photobucket.com/albums/ww278/vertical1dog/?action=view&current=Bottomline2001827x2061.jpg[/IMG][/IMG]

[IMG]s727.photobucket.com/albums/ww278/vertical1dog/#!coZZ4QQtppZZ20[/IMG]

Damn! I need to hire a 3rd grader to help me with this computer. Please forget the (broken links) and just view the stack at the above link. Sorry. Please go to page 4

[GrowlerBox]

Whattup, dog?

Good to see those cabs again and some more detailed pics showing Duke's evolution. Or is that intelligent design? Anyhow, nice fit and finish.

I'm still a bit suspicious of the port placement, which seems to risk losing mids and such out the back where they won't be heard well. That said, I am no techie either, and if they work, I guess they work .

[dog1]

I'm with you brother. For many years I thought that rear ported meant a loss of sound, tone and reinforcement. And when Duke proposed a flared port directly behind the low frequency driver, I thought it was maddness. I was wrong.

[GrowlerBox]

Originally Posted by dog1

I thought it was maddness.

Madness, I tells ya!

[DukeLeJeune]

Originally Posted by GrowlerBox

I'm still a bit suspicious of the port placement, which seems to risk losing mids and such out the back where they won't be heard well.

Don't blame you a bit for being suspicious!

I first tried flared-port-centered-behind-the-woofer on a home audio speaker several years ago, and the results were encouraging. It accomplishes several things:

1) Tuning frequency is a bit lower than standard modelling programs would predict, because the interaction of port flare with rounded Kappalite motor increases the effective port length without introducing sharp edges that can cause turbulence (chuffing). Not that it's totally chuff-proof, but the chuff-delaying benefits of the inner flare are not lost, and the port acts like it's an inch or two longer than it really is.

2) The airload on the back of the cone is very symmetrical, which is a good for long-excursion woofers crammed into small boxes. Otherwise, we can get distortion from cone rocking.

3) I believe that flared ports are inherently lower in midrange coloration than non-flared round ports, but any residual midrange coloration is fired off in a relatively benign direction.

4) With that 4" diameter port and its 6.25" diameter flare, combined with the relatively small magnet of the Kappalite motor, we get good airflow over the cooling fins on the motor.

Like most things in audio this is a juggling of tradeoffs, but I think it's a viable one for this application (3012LF shoehorned into a compact box).

[alexclaber]

Originally Posted by DukeLeJeune

4) With that 4" diameter port and its 6.25" diameter flare, combined with the relatively small magnet of the Kappalite motor, we get good airflow over the cooling fins on the motor.

A very good move with a small 4 ohm cab with high excursion limited power handling!

[jnewmark]

I know this is about the cabs you built, but I'm curious as to what you did'nt like about the Neox 212T ?

[billfitzmaurice]

Originally Posted by DukeLeJeune

Like most things in audio this is a juggling of tradeoffs, but I think it's a viable one for this application (3012LF shoehorned into a compact box).

I think it's important to make it clear that the main tradeoff is the midrange and high frequencies being able to exit via the port. That's far less a concern with a multi-way cab than with a full range driver, but still a concern, as it complicates cab placement.

[BurningSkies]

Just to be helpful, here is the cab in question:













Nice looking 'micro' version of a two way with horn.

The only thing I'd say is that maybe a bit more mid-panel bracing wouldn't hurt.

[Joe Louvar]

Off topic, but related ~
Just in case you gentlemen would like to know or haven’t heard “A Brown Sound” in San Rafael, CA USA is making hemp-fiber cones. Hempcone (patent pending) Speaker Cone Technology! Hempcone Speaker Technology 415-479-2124 info@hempcone.com

[KJung]

Looks like an early prototype of the Thunderchild. Makes sense. I assume the driver, the crossover, the porting, the tuning, and of course, the size and weight are all meaningful improvements. That being said, I'm sure that stack sounds great!

[BurningSkies]

Originally Posted by Joe Louvar

Off topic, but related ~
Just in case you gentlemen would like to know or haven’t heard “A Brown Sound” in San Rafael, CA USA is making hemp-fiber cones. Hempcone (patent pending) Speaker Cone Technology! Hempcone Speaker Technology 415-479-2124 info@hempcone.com

Besides it being hemp, what does it have to offer? The 15" neo doesn't have a spec sheet, and the spec sheet for their standard 10" ceramic bass speaker is pretty limited in actual info.

[Passinwind]

Originally Posted by dog1

I have never tried his Thunderchild cab, but would like to. But, it is hard for me to believe that it can compare with the original version he designed, and I built.

Apples and oranges, considering Duke uses a custom driver in the TC cab. For some of us, it's much, much nicer than a stock 3012LF. But as always, a different set of compromises. Vive la difference!

In any case, that's a very nice build and I'm sure it sounds great.

[Joe Louvar]

Originally Posted by BurningSkies

Besides it being hemp, what does it have to offer? The 15" neo doesn't have a spec sheet, and the spec sheet for their standard 10" ceramic bass speaker is pretty limited in actual info.

Strength, longer lasting cones, etc - call or write them, they can tell you more.

[BurningSkies]

Originally Posted by Joe Louvar

Strength, longer lasting cones, etc - call or write them, they can tell you more.

I've not had a problem with the strength or 'life line' of traditional cones. What I'm more interested in is things like x-max, xlim, Vas. You know, things that might tell us how the speaker performs.

[Joe Louvar]

Ok, but if you want to know more call or write them.

[dog1]

Originally Posted by jnewmark

I know this is about the cabs you built, but I'm curious as to what you did'nt like about the Neox 212T ?

I didn't mean to be misleading. I loved the NeoX. But considering that I only used the 2 112 cabs that I built, the three that I sold were collecting dust for almost two years. The GB was solid, punchy and clean. Maybe the best 212 cab available at that time. But, after having a heart attack about 8 years ago, I got to the point that moving gear was next to impossible for me. After having a near miss about three years ago I needed light. At 31 and 34 pounds, the two cabs I use are easy to carry and load, even for an old fart like me. I carry them one at a time.

As for tone though, the 2 112's I use are superior to the NeoX, or any other I have played through. Everyone hears things differently, and most are looking for their "ideal" sound. I am just fortunate to have found what I am looking for, so I look no further. The stack that I use could just collect dust in someone else's home, just as the GB, Aguilar, and Peavey did in mine.

[dog1]

Originally Posted by BurningSkies

I've not had a problem with the strength or 'life line' of traditional cones. What I'm more interested in is things like x-max, xlim, Vas. You know, things that might tell us how the speaker performs.

Yeah. I mean no disrespect, but for the life of me I can't fathom how hemp cones will make a speaker better sounding, or more durable. I'm laughing to myself because I am thinking about the "Reefer Maddness" movie that Growler Box posted (a movie that I saw many years ago) and am hoping that those guys don't show up and grind up the cones and smoke them.

[Joe Louvar]

Dog1 it may seem funny - but fiber coning isn’t a joke. Anyway, those who want to know about leading technology may be interested - others, maybe not.

[dog1]

Sorry. The hemp fiber cones are not funny to me. The "Reefer Maddness" movie is. (was)

Thank you for providing a link to the manufacturer.