External Crossovers

[The Black Adder]

Has anyone made their own external crossovers by removing the originals from the cabinet? If so is there any improvements in sound?

I've been toying with this idea for a bit now but just wondering if the extra set of cables negate the improvements gained from vibration and magnetism.

Cheese
Joe

[The Black Adder]

lol

[Beobloke]

Well worth doing IMHO. I did this on my Ferrograph S1s and it made a noticeable difference.

Also, for those cynics out there who say it can't possibly make any difference, consider for a moment that the S1 crossover fetaures six inductors. Inside the cabinet these are sat a matter of a few inches away from the rear of a KEF B139 drive unit with its whacking great magnet! It's not difficult to work out that moving all these ferrite cores away will make a difference to their behaviour.

One thing to remember though - don't, whatever you do, put the PCB into a metal box....

[Reid Malenfant]

Well worth doing IMHO. I did this on my Ferrograph S1s and it made a noticeable difference.

Also, for those cynics out there who say it can't possibly make any difference, consider for a moment that the S1 crossover fetaures six inductors. Inside the cabinet these are sat a matter of a few inches away from the rear of a KEF B139 drive unit with its whacking great magnet! It's not difficult to work out that moving all these ferrite cores away will make a difference to their behaviour.
Aye, get them out of the enclosure... Vibration is a bitch, minimise it as capacitors & to an extent inductors are microphonic ;)

[Rare Bird]

But for people who use speaker properly & not like some kind of PA system! i hear no vibration interaction issues

[Welder]

Yes and maybe.

When I rebuilt my Volts I brought the crossovers out of the cabinet and mounted them on the back of the speaker enclosures.
I did this for a number of reasons;
a) to help get an increase in internal volume with major changes to the exterior dimensions
b) the internal wiring actually works out at less distance than before.
c) it makes crossover tuning a lot easier because of easier access
d) I vented my crossover enclosures and this helps keep the component temperature down.
e) it helps minimize the possibility of the crossover components interacting with the driver magnets
f) As Adam says, don’t use a metal enclosure, not even aluminum.
g) it reduces the chance of internal box vibration effecting the crossover as Mark writes.

I can’t say whether it had any sonic benefits because it was a complete rebuild so lots of changes. However, for the reasons above it is quite a sensible option if you’re building from scratch. I’ll let Andre be the final judge of whether or not there are sonic benefits ;)

[Rare Bird]

Big deal. if my speakers were meant to have external crossovers they would.

[The Black Adder]

Big deal. if my speakers were meant to have external crossovers they would.

That could be to keep cost down?

[Rare Bird]

That could be to keep cost down?

Once apon a time you used to buy a stereo & listern to it. What happened?

[alfie2902]

Big deal. if my speakers were meant to have external crossovers they would.

Just like mine ;)

[DSJR]

Once apon a time you used to buy a stereo & listern to it. What happened?

Normal people do Andr'e :lol:

Some of us here are fortunate to have one setup for listening to music through and a secondary one for bodging :lolsign:

[The Black Adder]

it's great to have a test bed to try stuff out... if it works well change the main system too!

[bobbasrah]

John's list pretty much covers all the bases (I guess the question is over existing cabinets rather than new build where you can design these issues out)

Why not test the idea and decide yourself? It should not take long to resolve. Cable runs should not be excessively different to be critical.
Where do you site the crossover if this proves worthwhile? Plastic or wood boxes on the back of the cabinet do little for aesthetics.

Are components affected by audio frequencies in a sealed box? Gut feeling, yes, logic, no.

[Z-A]

I built external crossover cabinets for all of the electronics built into my Martin Logan Spires, and definitely feel that it is worthwhile. Would I swap back? No way, absolutely not. Mine can be seen on the tweaks section of the martinloganowners.com site
http://www.martinloganowners.com/forum/showthread.php?9600-Spire-with-External-Crossovers-amp-Electronics.
If you think that at some point you might rebuild the crossovers, then build the cabinet/ box a bit bigger than needed now, the extra space will be needed for larger caps etc.

Any questions feel free to ask..
Cheers,
Paul

[YNWaN]

Paul, congratulations on a very nice job. I have done something similar to the cabinets of my speakers. As a matter of interest, how did you fix the granite panels to the cabinet?

I think you will find quite a significant improvement upgrading the capacitors.

[The Black Adder]

Paul, that looks superb matey! :)

[Z-A]

Thanks Joe & Mark,
Replied to your message Joe.
I use many vertical lines of silicone mirror adhesive to bond the stone, they are supported by some aluminium tabs underneath too, not visible. Surprisingly, I did hear continuing improvements for the few days that the adhesive took to cure, likely the resonances being damped by the stone better. The crossovers were very close to the magnet and coil of the 10" bass driver in the Spire, so removal was beneficial here, other speakers may not be as cramped inside though.
Regards,
Paul