Ultimate Open Baffle Gallery

[diypole]

Erik that is an excellent idea and implementation.

Great build, kudos!

[vitalica]

Originally Posted by pkaro

Your planned build is super interesting. Could you share some of the thoughts behind your build? For example, why you went with a 3 way and a non-dipole diaphragm tweeter, and what you expect the polar response of the system to look like?

Your choice of some components, the frame and baffle shape remind me of the Kryon Audio Kronos. Did you come to this structure or is it a deliberate hommage?

How will you implement the crossover, amplification, DAC, etc? Will room correction come into play?

Excited to see more renders, photos, and description!

Initially I wanted to go on TPL200 and 2xAE 15.
But I talked to John from Acoustic Elegance, he told me the following:
"I have had quite a bit of experience with the TPL150 and the TPL200. For open baffle use, you could go to 1000hz because the power requirements are much lower than in pro sound use. However, they are better crossed higher. Distortion will stay much lower.
I wouldn't go with the LO15 up past 1000hz. Any 15 "narrows to less than 90 degrees by 800-850hz. That is really the upper end you want to take a 15" driver.
Personally I would use 2x Dipole15, the TD8M, and the TPL200H. Crossing about 250hz and 2500hz. The TD8M has plenty of output to keep up with the TPL200.
The 2x Dipole15's will give you far more output ability down low and the TD8M gives the best midrange of all the options."
So I decided to go for the 3-way active version, including the TD8M speaker.

You're right, I was inspired by Kryon, for many years I wanted to do something similar

The system will be made up of W10 - JRiver - EKIO software crossover - an 8-channel DAC (DAC8PRO) - two XA30.8 amplifiers for highs and mids + a class D PRO-2M amplifier for bass.
I will also try the correction.

[ErikdeBest]

Originally Posted by diypole

Erik that is an excellent idea and implementation.

Great build, kudos!

Thank you! Together with my wife we built a "room divider line array speaker" set which made the Frankenstein obsolete for the moment, but once the line array is tuned in I could equip Frankenstein with the NEO10 and Mundorf AMT D17.2 (and active crossovers) to see how they compare.

As this thread is meant for pictures, here one of the line arrays. I have a thread for them, which needs some updates

Dipole Line array with GRS Slim 8" and Visaton WS25e

[joensd]

Very nice room divider! I see 9pcs of WS25E!

[pkaro]

Thanks for the reply. Your choice of DAC is great, I have been thinking about upgrading from my miniDSP 4x10HD. Those Passlabs amps look and likely sound awesome, it seems you're not constrained by budget in your build!

The Kronos is of course a drool-worthy system, though with regards to the other comments regarding the benefits of 4 way systems, I wonder how even the polar response is around the crossover point between the woofer and the tweeter.

Did you consider other options for the tweeter section? Using, for example, two back-to-back BlieSMa tweeters BlieSMa_T34B-4 would allow you to have a dipole tweeter section. They have excellent FR, super low distortion, great off-axis characteristics, and can be crossed over at 2,5 kHz too. I'm not sure how well they would integrate with the AE woofer though in terms of FR, dispersion, and sound.

[TimA]

Having recently finished my first open baffle design I thought I'd add it to this interesting thread.

I'm very pleased with their very open and transparent sound.

[joensd]

Having recently finished my first open baffle design I thought I'd add it to this interesting thread.

I'm very pleased with their very open and transparent sound.

Love the design. Somewhat futuristic but still elegant and classic. Unique for sure.
How did you construct the frames for the cloth?

[pkaro]

Originally Posted by TimA

Having recently finished my first open baffle design I thought I'd add it to this interesting thread.

I'm very pleased with their very open and transparent sound.

Beautiful, particularly your work with the fabric covers looks very nice. Could you share further specs of the speakers and your system, and some of your design considerations?

[TimA]

Thanks for the favourable comments.

The rear frames are rather complex and took a few days to construct. Materials are a combination of hardwood and mdf. They are at least strong enough not to fall apart on their own. I considered easier/stronger alternatives but none would have been as open acoustically. They are attached with small magnets.

Design criteria was that they need to sound at least as good as my Quad 63s, which they do, and to look good. from previous listening experience I wanted to keep the capacitor count in the treble section to a minimum, therefore the HP filter needed to be 2nd order at most, hence the need for a 1.5kHz notch filter connected across the tweeter which was not necessary with a steeper slope but which I consider much less of a problem sonically than a second series capacitor. I have attached the Xover.

Drive units are
Eminence Alpha 15a
Seas H1571
Mundorf 2330 (chosen due to its open back design).

Modelling in Tolvan Edge showed that the midrange needed to be offset as far as possible to the side for the flattest response but this also made the rear frame more complicated due to the large magnet. Another consideration was keeping the 'wings' as small as possible, again for the most open rear radiation.

[pkaro]

Thank you for the additional details. The choice of components looks fine indeed and the overall FR is smooth!

Have any issues arisen with choosing to have such a shallow low-pass filter for the sub-woofer? At 2 kHz it's only 20 dB down, and while I'm not aware of the details of how the Eminence performs, sub-woofers often have issue with 2hd, 3hd at those frequencies. Did you consider going for active cross-overs to implement steeper curves?