all CSS heavyweight compact 3way

[Henkjan]

Originally Posted by WaVeInFoRm

A sports hall is a very eco'ey enviroment... wouldnt you be better of at the top of a hill... or at least in a hot air balloon.

and if that probably isnt possable, surely halfspace in a field is more accurate than a hall that bounces sound around as efficently as a basket ball

I did a gated measurement, that keeps out the echoes.

outside: not with our weather and the other noises outside (wind, birds, rain, traffic, kids, wife, dogs, Ronaldo, etc) would introduce too much noise into the measurement.

[5th element]

Yes I know the measurements aren't smoothed, however if you take measurements that really are completely free from room measurement artefacts then smoothing isn't necessary.

Such as this, 1) the clean impulse.



Followed by 2) the completely unsmoothed frequency response.

[DavidL]

Perhaps the measurements are being contaminated by very low frequency noise that isn't apparent to the OP but is being picked up by the sensitive mic? For instance, A/C air rumble, traffic rumble, etc.

[5th element]

Noise at specific frequencies typically shows up in the measurement at the frequency that the noise is at. The OPs measurements look just like measurements that are contaminated by reflections.

For example here's the frequency response of a tweeter with a very short gate first, then longer and longer ones that capture small reflections from the room. The last one captures a particularly bad one, but you get the idea.



If your response ends up looking like this.



Then it often means that you've got a noisy system with broadband noise. You can easily reduce its effects by taking say 5 measurements that are then averaged out. ARTA does this automatically if you ask it to.

[Henkjan]

So, here is the filter schematic:
Trio CSS - filter schema.png

Some clarifications on the main components:

• the + and - in the driver symbol indicate how they are connected: the mid normal (so driver + on amp +), the woof and tweet reverse polarity (so driver + on amp -)
• All capacitors preferably >160V
• For the 8.2mH inductor I chose an I-core type, probably the best price quality ratio of the cored types; aim for the lowest series resistance your budget allows for
• use air core inductors (foil type if budget allows) for all others, to be sure that you'll achieve the lowest distortion possible; there is no benefit in thick wires (in the mid and tweet sections) so no big dent in the budget and limited benefit from solid cores
• RCL in tweeter net and the small caps over the series inductors of mid and woof are for the final touch, if budget is tight these can be omitted
• the 1uF over the tweeter resistor is optional and the effect subtle, let your ears decide

[badman]

Regarding the efficacy of small roundovers, I always look at it this way- if one traced rays from the driver to the edge of the baffle, only those s that are perpendicular to the cabinet edges will encounter the minimum size of the roundover. Those rays that are angled relative to the baffle edge encounter a much slower transition from 2pi to 4pi and thus the small roundover is effective lower in frequency than the nominal roundover size would seem to be capable.

[Henkjan]

while waiting for the "final" filter components to arrive, been playing a bit with the damping and placement of the speakers. first I added more twaron, now there is 200gr elves hair in the woofer compartment. subtle difference, but enough to justify the effort.

placing them proved an issue in my listening room, because I noticed a large difference in bass if I moved my listening position by a foot or so (it was easier to move myself than to move these heavy boxes with the filter free-wired on a piece of wood), much more than I had with other designs. having a deep bass does not make everything easier to be continued.

but apart from that, I am happier every day with what these deliver. the speakers disappear completely, imaging is among the best I've heard (at least the same as a good fullranger, which is my reference; this really surprised me, never expected that a multi-way could be a match for a full range in this aspect), details are beautiful, instruments and voices are as if the musicians are in the room playing live. orchestral music is impressive, especially live recordings.

Now all I need to do is to convince my wife that these deserve a place in our livingroom

[mwmkravchenko]

Soldier on Henkjan. The sharks are out and your wearing tuna flavored shorts!

Well thought out, and your measurements will improve with practice.

[Henkjan]

did you mean solder on?

just received all the final filter components, next is to make some nice prints (a zelfbouwaudio.nl member is making the prints for me) to mount them, and then I'll also finnish the veneer

@Mark: a bit odd to notice that much of the discussion was on details of the measurements, and less on the loudspeaker design or the filtering

[mwmkravchenko]

Tis the perils of posting.

I'm sure they sound awesome.