Caladan by Clayton Shaw DIY

Like many on here, I'm going to attempt to clone the Caladan as my first DIY project to use with my 300b Audion amp,

Has anyone actually heard the Caladans with a low power tube amp?

After having built two pairs of DIY open baffles with large woofers/passive x-overs, my gut sense, and a look at the few online comments I can find regarding amplifiers and the Caladans, is that they would want significant power to deliver solid bass. To me, their bass is the only truly impressive thing about them, from my hearing at the Seattle show. They are priced well and nice all around, but from hearing them, my thought was: “the midrange is really good for a 12” pro woofer”---which does not mean that it is among the best, so to speak.

At this point it is my experience that open baffle-low bass needs power, especially when using passive crossovers. Designers have circumvented this in the past by using large, high-ish sensitivity, hi Q, pro woofers; but those woofers have higher Fs, thus cannot go very low, and have less precise bass transients. They make more bass by having less electromagnetic control over the cone.

This may well go along with the single-ended tube/valve aesthetic---which seems to emphasize hard-to-measure timbrel qualities---that are quite pleasing to many---at the expense of powerful, precise bass response (which the Caladans do seem to have, with the right amplification).

Any open baffle with relatively flat response, decent bass and low distortion can be a revelation to those accustomed to box speakers. The sound-stage can just be so open and deep. Sitting in the “sweet-spot”, tends to matter much less as well.

Interesting to note (again?): the Caladans are di-pole only for the mid-woofer response. There is no rear tweeter. Due to the low order roll-off, the woofers probably do have significant output above the 1000hz crossover point.
 
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This is really interesting to me Howard, and fits with my assumption that 300b amplification might not play nicely with the Caladans. I’ve recently begun to think more along the lines of a 3-way, but I’m presuming that would involve significant tinkering with the XO’s.

Do you believe that the monopole tweeter arrangement is less than ideal for an open baffle - ie are there better options to consider?

I’m still keen to make these things as it seems like a good place to start my DIY journey, but being mindful that they aren’t necessarily going to be end-game. Would you agree?

If anyone has played their Caladans via 300b amps, please do let us know your thoughts!
 
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Hi Marshall,

I don't remember what I thought about the lack of the rear tweeter when I listened to the Caladans at the show. A rear tweeter tends to make a more expansive, deeper, sound-stage, often at some expense of precise imaging. With a rear tweeter you can experiment with relative level and filter knee-frequency to vary the effect. On a commercial offering, an extra tweeter would increase the cost and maybe affect sales. For DIY, the cost would be minimal enough.

For DIY+300B: To get started you might want to try a sensitive full range driver with bass support on an open baffle. This idea has been discussed a lot for about 20years. Tons to read on this website. I forget all the acronyms, but F.A.S.T. is one, I think. Search for references to Martin J King. He first used a small Fostex and an Eminence Alpha 15, as I recall (remember to be wary of links on less-secure http websites). There are many “full range” options these days.

I like the 3-way approach. I have found that using lots of drivers does not mean that the crossover has a high component count. If drivers behave well outside their assigned range, the crossover slopes can be low-order. If a driver sounds pretty good with no filter, there is a good chance that it will be easier to work with. The woodworking part is more intensive with more drivers, naturally.

For a first project, an established design, especially one with a simple crossover, is probably better.
 
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Word on the street is that Clayton changed the crossovers for the Caladans! There has been a minor "facelift". From what i can tell there is now a 13uF cap on the tweeter. There is also another resistor in the mix. Not sure of any values that has changed beyond the one cap or how it's configured yet. The baffle thickness has also been increased from 1,5" to 2" thick for rigidity.
 
Sorry, my bad! It's supposed to be a 15uF cap and a 0.1uF Jupiter copper foil bypass cap in the tweeter circuit. And it looks like there is also a resistor in the woofer circuit. I have a vague memory of someone talking about that in this thread? How would that effect the frequency response?
 
To be fair, the finish looks great. But it is not what is advertised. I saw a post on another forum from a customer who got a pair that was mismatched. One of the speakers had almost like a maple burl holographic effect from the wood while the other speaker was kind of matte and darker in color. I guess this could happen to every manufacturer. Too bad they had to wait for over a year for that realization...
 
Hi everyone,

I'm really interested in building a DIY version of the Caladan open baffle speakers by Clayton Shaw. Unfortunately, the original speakers are out of my budget at $3500, so I was wondering if anyone here has designed or built their own DIY version of the Caladans and would be willing to share their CAD files or plans for the open baffle design.

I’m curious how close your DIY builds are to the original in terms of sound and aesthetics. Any details on drivers, crossovers, or overall design would be incredibly helpful. If there’s a specific resource, website, or person where I might find CAD files or detailed plans, I’d greatly appreciate it.

Thanks in advance for any help or guidance!
 
This is the information i have gathered the past year.

The Baffle
2" thick hardwood: H - 38" (960mm) W - 18" (460mm). 45° chamfer around woofer - do not chamfer the full depth of material, check pictures for reference.
With the help of adjustable feet, there is supposed to be about a 6-8° tilt backwards, helps with time alignment of the drivers.

Tweeter: Dayton Reference RST28F
Woofers: Beyma 12BR70

Crossover parts:
4x 20uF cap
2x Jupiter Copper Foil Beeswax 0.22uF cap
2x 7mH air core inductors
2x 1,25mH air core inductor
2x DPR10-0.51 0.51 Ohm 10 Watt Precision 1% Resistor
Jupiter cotton cable for the drivers.

Recently the crossover was altered by Clayton Shaw and i don't know the exact value or configuration yet. There is just minor differences from what i can tell.

If someone has other information or want to add anything, please do.
Good luck!
 
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