Why not put crossover networks in accessible compartments?

Because it is difficult to predict what people want we (Analysis Audio USA) decided to let the customer decide whether they buy inboard or outboard crossovers. Some people place their Analysis speakers in a living room and don't want extra boxes and wires. Others want every last ounce of performance and choose outboard crossovers. Others like to have the option of trying active bi-amping at a later time. Even though the Analysis chassis/cabinet is rigid and fairly well damped there is still some vibration. Being a flat panel speaker the cavity for crossover parts is quite small so extra isolation is almost impossible. There is a noticeable improvement using the outboard crossovers. I have demonstrated this many times to potential customers. Outboard crossover cost more. That is a consideration as well. We use Dueland, Mundorf and V-Caps in our REF outboard crossovers. Those components do not fit inside the speaker cavity. We let the customer decide: inboard crossovers, outboard crossovers using the same parts as the inboards and outboard REF crossovers. I understand why most manufacturers don't want to encourage their customer to redesign their speaker crossovers. Besides the obvious, technical support becomes challenging.  It is much easier to offer one flavor

Yes indeed. Stock sand cast resistors that sound relatively grainy compared to the Mills MRA or the even better Path Audio resistors. The Mills would only cost builders some $4 each, but instead they use $ .25-40 cent crappy sand cast resistors. This in $30,000 speakers! Spend the $4 bucks each builders! 

Open baffle loudspeakers usually have their crossovers on a board right behind the upper drivers. Danny Richie does his GR Research OB’s that way, and uses unusually high quality parts (Sonicaps, Mills resistors) to create them. In his Tech talk Tuesday videos, Danny takes apart mainstream speakers that have been sent him by clients for upgrading, showing all the crap x/o parts used in even fairly expensive speakers, and describes what he replaces them with.

@mofojo . It does amaze how many, if not most, speakers that retail for up to $30,000 use $ .40 cent resistors and $7 capacitors. I mod and upgrade speakers for myself and clients and see this all the time. The sonic gains realized with a few well chosen and implemented upgrades is shocking.

Volti Audio is another.

Living Voice is another company that uses outboard crossovers. Other benefits beyond vibration control include...

- More room for proper spacing of inductors.  Far too many speakers have them jammed together due to limited space and this negatively impacts the Sonics as they interact. 

- Some of the better parts are just plain huge like PIO caps and heavy gauge, air core inductors for bass drivers. They won’t fit in the cramped internal speaker cabs. 

I believe a lot of these manufacturers would not have the crossovers accessible on purpose to hide the cheap parts they are using. 

Thank goodness the dismal science doesn't rule everyone.

Some speakers do have a separate compartment such as the Dali Epicon line. Great way to keep the parts out of  direct proximity of the bombastic cabinet. Nola and others use outboard crossovers which add wiring complexity, but totally removes the vibration sensitive parts from the cabinet.

Isolating the crossover from vibration is a good thing, easily accessible compartments that allow changing components is a different thing, how often a speaker need to replaces crossover parts?

I believe encase in resin helps isolating the crossover components from vibration.

A few speakers used to come with the crossovers encased in an entirely separate box, that you then connected with multiple leads to the speaker itself.  You don't seen much of that anymore.  If I remember correctly, one reason stated was trying to avoid vibration.

Vandersteen use a slew of high quality parts, custom drivers, graded and sorted to match within amazingly tight tolerances... and then the whole shooting match goes in the Anechoic chamber for tuning....

Treo and up filters are in a separate cabinet within the cabinet w constrained layer damping and a very unique buss bar/lug attachment to the other driver and input connection, heavy duty :-) I might post up picture on the Poverty Bay system page...

Sorry, I was unclear about something:

Wilson, like other highly regarded makers, uses straight off the shelf parts

Here what I meant to say was "off the shelf drivers."

Hope that clarifies.

so how do you know what they use?

No one does, it's a trade secret. A secret most other manufacturers only do minimal work, if any to hide. For instance, using branded OEM caps. You can't tell if they are expensive or cheap and you can't buy them  yourself.

I should point out not all speaker makers use cheapest possible parts or go through any more trouble than putting crossover components in the speakers.

B&W uses Mundorf in some speakers, as does Magico and Joseph.

They literally pot (encase in black resin) their crossovers so you cannot see anything, even if you disassemble the speakers.

so how do you know what they use?

I think Wilson kind of helps answer this question. They literally pot (encase in black resin) their crossovers so you cannot see anything, even if you disassemble the speakers.


Wilson, like other highly regarded makers, uses straight off the shelf parts you could buy yourself. If you knew what the crossover values were, you could make a straight up clone. Focal used to have little windows so you could see the parts.


It’s also true that the economics are such that putting in high quality crossover components is rarely a win for makers. This makes a couple of brands like Focal and Wharferdale ridiculously good upgrade targets.


Of course, if you want to play with parts this badly, the DIY speaker kit market is probably what you should be looking at. :) Lots of kits and plans out there which you can tweak to your heart's content.

It is also extra expense and complexity in a build, which raises retail prices, in order to satisfy maybe less than 0.01% of the potential buying public. That one in 1000 or less...who might tear the speaker apart and modify it. 

This^^^ Duh! 

Economics, the dismal science, apparently no longer taught or everyone would be able to figure this out.

The compartment idea is nuts. A better idea is to put the crossover outside the speaker cabinet. This has the added advantage of improving sound by removing the crossover from the high-vibration environment of the speaker cabinet. But again, the improvement is so slight compared to the cost it'll never happen. Except among modders. But they already know and have been doing this for years.

Its not practical when designing speakers.And in some cases it will look bad.Good luck though!!

The Watkins WE-1 from the early 80's had a recessed area covered with a Plexiglass cover so that the crossover and the circuit board it sat on was visible. It was done not so the owner could fiddle with it; it was done because the crossover actually looked good and to show that the speaker wasn't just a cabinet with twenty bucks worth of resistors and capacitors in it.

It is also extra expense and complexity in a build, which raises retail prices, in order to satisfy maybe less than 0.01% of the potential buying public. That one in 1000 or less...who might tear the speaker apart and modify it.

There are other reasons to compartmentalize the crossover, and that is separation from the physical interactions of the drivers energy input into the box. To get the crossover isolated in all ways.

We use outboard passive crossovers, in the speakers we have made, over the years. Which makes it easier to go to active crossovers.

pmboyd

Why not put crossover networks in accessible compartments?

Some have, such as Infinity.

Because most designers don't want you messing with them. They work hard to dial them in just the way they want them.