My Sachiko Build Process

[HCB]

Aaaaarrggghhh. try again...

[HCB]

mmmmmm, and again!

[cervelorider]

Nice work on the Sachiko! I'm not sure Scott & his Frugal staff realizes, or at least it is worth repeating, how much his designs and effort mean to people who are creating and enjoying his works of musical art.

[Scottmoose]

I'm glad you guys are enjoying them.

Dave & his frugal-horn contributers would be a more accurate description. If it wasn't for his hosting of the site, many of the designs would be at the very least, far harder to find, and in my case, stillborn.

[hm]

Hello,

looks good,

are there measurements available,
specially from the mouth and an imp.

Is there no problem with the mids?
look this link:
part 9: Fe206E aktualisiert neu
http://www.joern-hohmann.de/
compare the Fostex with the
selbstbau measurements of the FE206E,

Therefor it would be helpful to take a measurement,
to see what happens in the mids.

Is for this horn any measurement available,
from the constructor, i found only poor simulations.

[Scottmoose]

Indeed they are poor Horst. Unfortunately, though the existing MathCad software can handle a horn & air cavity, it does not take the effect of the folding scheme into account (no software does AFAIK). The folding is very deliberate -it wasn't a case of simply trying to pack the horn into a given box: it's a part of the design, based on Olson's work -see his seminal text Dynamical Analogies if you're interested. It works in a couple of ways, the most significant being that the multiple bends in the first part of the expansion attenuates those higher frequencies the air-cavity does not filter off, both from passing through in the first place (as you know, HF hates sharp bends), and also preventing standing waves at the mouths from being reflected all the way back along the path & modulating the driver. There are several other elements to it as well -again, it's a case of a little latteral thinking though as it doesn't involve horn theory.

All of this because I don't like too much damping in a cabinet... I must be mad...

Anyway, the cabinet in practice should actually have little effect on the response above 300Hz & needs little damping. I'll leave comments on the sound up to people who've built them, though Derek noted their smoothness (it was nice to get that confirmation).

Hopefully someone will be able to measure a pair at some point. Word of advance warning: this one won't be an easy box because you have to measure the total response (it's a single horn bifurcated. I'm working up a curved front as an option for it -that one will be easier to measure in practice due to the focusing of the wavefront on a specific point).

Hope that helps (& best regards for a happy new year to you all)
Scott

[hm]

Hello,

that means no controling, no measurement???!!

whow, do you buy a porsche like this?

I am afraid by the using material, and most
parallel horn parts, my experience tells my
you load enclosure sound in the mids.

[Scottmoose]

And my experience & physics tells me they only have what I designed into them. I work within physical principles which last I checked, don't have a habit of changing. If you want to investigate the physics, I've pointed you in the right direction. If you don't want to investigate it, equally, that's up to you.

Actually, while we're discussing this issue, & just to throw a complete spanner in the works, I remember Terry Cain commenting on a conversation he had with Dr Bruce Edgar about gain a few years back. The latter was apparantly chuckling somewhat about concerns over gain. His take was that it doesn't matter -gain is gain. Just goes to show how many different views there are around.

[cervelorider]

I'll weigh in since I'm one of the few who has built and lived with the Sachiko for many months.
One also doesn't buy a Porsche looking at the specs on paper only. One takes it for a test drive. Reading about a Porsche and taking one for a drive are two different experiences. Climbing in, noticing the attention to detail and craftsmanship, wrapping your hands around the steering wheel, smelling the German car smell, turning the key, carving turns... the specs. are quickly forgotten and the whole experience overwhelms you. I've driven a Porsche and owned a BMW 325 for several years.
The Sachiko is among the finest sounding cabinets I've ever experienced and well worth the effort to build. I found them to be quite smooth and extremely dynamic. You forget about specs and measurements and are transported into the music.

[TerribleT]

Hello,
I have a pair of Fe206E drivers and the Sachiko looks like a possible box to make them sing. Can someone direct me to a site where the Sachiko box design dimensions are given? Thanks in advance.
Regards,
David