Outboard Crossovers - homebrew Kan Mk1

My only experience of outboard passive crossovers with KANs was some years back in the main stores area of the factory, where there were a pair of active KANs being used to pipe Spire FM into that particular space.  IIRC, they had Naim PXOs attached to them.  I'm not sure how ideal they were, or even whether they had been modified in some way to suit, but they seemed to work - not that one could get any idea of how well, considering their less than ideal positioning...

Hi thanks Richard........... I never expected a reply referencing Kans specifically !!!

I am inclined to try it anyway ......... but it would be nice to get more feedback......... if anyone else has experimented ....... even with other speakers...

Rich, outboard passive crossovers were a key feature of Naim speakers.  They also made it easy to remove the passive crossover to upgrade to an active crossover.

What about the Aktive crossovers that Naim built specifically for the Kan’s? I believe it was called the NAXO. I also have Kan’s and would love to hear them driven that way. 

My active Kan 2s came from the previous owner with what was described as external crossovers should they be used for passive operation. The PCB is clearly branded Linn. Anyone know if these were always meant to be external or if someone just adapted some internal ones for this function?

Richieroo posted:

Hi I am finishing my Linn Kan Mk1 - speakers and I was looking at the crossover which has a couple of coiled chokes  ......... and I looked at the proximity of the crossover to the B110 magnet ........ and thought ............ hmm if the coils vibrated within the flux of the magnet - that would generate some sort of emf........ possibly at certain frequencies. So bearing in mind - the proximity of the magnet to crossover do you think it would be a good idea to have external crossover boxes - well away from the magnetic field....... has anybody any experience with outboard passive crossovers???

This makes sense to me.  In fact, a couple of weeks ago, I designed up a new crossover for my speakers, using modern components, and part of the design was a double constrained layer box with thick walls, with vibration Isolation.  It will be several months, but I will keep you posted how that works out.  Perhaps one layer should be magnetic shielding.

Baillyhill

Sandals posted:

What about the Aktive crossovers that Naim built specifically for the Kan’s? I believe it was called the NAXO. I also have Kan’s and would love to hear them driven that way. 

Yes, the NAXO could be specified to work with the active KANs, although, before the arrival of the Naim SBL, DBL and IBL, most were used with SARAs and ISOBARIKs.

ricsimas posted:

My active Kan 2s came from the previous owner with what was described as external crossovers should they be used for passive operation. The PCB is clearly branded Linn. Anyone know if these were always meant to be external or if someone just adapted some internal ones for this function?

IIRC you could buy the Kan 2 version as passive (with internal crossover) or with no crossover and two sets of terminals on the back for active drive. It looks like a Linn or dealer supplied Kan 2 crossover to allow someone to use active Kans passively rather than some attempt at making a previously internal crossover external.

Thanks guys ... very interesting to see the Kan Mk2 x-over ..... falcon could only supply the Mk1 x-over.  Have you any closer shots and also the track traces on the reverse..........???

Richie - are you making Kan 1 copies using the back in production drivers from Falcon and home made cabinets or you have an old pair you're working on ?

Just curious as to your homebrew title...

James

PS - Any pics ?

Richieroo posted:

Thanks guys ... very interesting to see the Kan Mk2 x-over ..... falcon could only supply the Mk1 x-over.  Have you any closer shots and also the track traces on the reverse..........???

I’ll take some this weekend and report back.

Hi James ... I am using matched falcon b110s and hiquivon tweeters.... and a hard wired version of falcon x over... The cabinets are to my design...18mm ply centrally braced... with silicone embedded 2mm lead internal cladding.... the cabinets are totally dead...and weigh about 18kg.....the 110 is rebated into a thickened baffle. The tweeter has rear cladding over internally to stop internal  pressure effecting it. Cabinet is lined with felt over lead...and it will use glass fibre filling...when finished....not very densely packed..... Hopefully it should sound pretty good.....I will report back. If all is not well ... I will buy a falcon cabinet..... It has been fun building it.....  I am about 2/3's the way through build....phew.

Nice - that sounds like a lot of fun. Look forward to hearing how they turn out 

Back in the day Linn shifted the cross over for the passive Isobariks from inside the box to sit under the cabinet tucked inside the stands. It meant that the cabinet/driver construction for the passive and active was the same, and of course upgrade path was made easier. I seem to remember that the Linn guys suggested it was also a sonic upgrade to  the passives too. But they were fiddling with lots of little things over the years so impossible to say.

I'm thinking it would be a better bet to have the crossovers external. I have had good results with hard wiring the cross over, rather than it all mouted on a pcb. But these days I am not sure this applies. Good speaker manufacturers can apply modelling to the crossover design which we Heath Robertson loons simply can't match. 

steve95775 posted:

Back in the day Linn shifted the cross over for the passive Isobariks from inside the box to sit under the cabinet tucked inside the stands.

It meant that the cabinet/driver construction for the passive and active was the same, and of course upgrade path was made easier. I seem to remember that the Linn guys suggested it was also a sonic upgrade to  the passives too. But they were fiddling with lots of little things over the years so impossible to say.

???? STEVE95775,...It was better???????? 

But even better was to completely move the passive crossovers from the stands,..so that they had no contact with the Isobariks.

/Peder ????

Thanks guys all interesting stuff....

Peder posted:

steve95775 posted:

Back in the day Linn shifted the cross over for the passive Isobariks from inside the box to sit under the cabinet tucked inside the stands.

It meant that the cabinet/driver construction for the passive and active was the same, and of course upgrade path was made easier. I seem to remember that the Linn guys suggested it was also a sonic upgrade to  the passives too. But they were fiddling with lots of little things over the years so impossible to say.

???? STEVE95775,...It was better???????? 

But even better was to completely move the passive crossovers from the stands,..so that they had no contact with the Isobariks.

/Peder ????

Yes we have learnt a lot about mechanical isolation of electronics and microphony. Looking back at the early days, it's hard to separate out the tweeks that were the result of applying thorough attention to details from the modification driven by inspired madness. I think of the attention that Naim put into the banana  plugs. Who would have thought of this back in the 80's.

I agree....the isolation in the hi line cable or sl cable plugs .... is amazing...great engineering

Hi Ricsimas ..... have you managed to take the x over pictures for me..........

Here you go:

Many many thanks ........ wow ... that's had a bit of surgery!!! Looks like the bi-wire banana inputs have been linked ........ all I need to find out now is the size of the chokes ........... the bass one looks considerably altered compared to Mk1 ........ it's much larger.........

Richieroo posted:

Many many thanks ........ wow ... that's had a bit of surgery!!! Looks like the bi-wire banana inputs have been linked ........ all I need to find out now is the size of the chokes ........... the bass one looks considerably altered compared to Mk1 ........ it's much larger.........

Yeah, clearly someone played a lot with the original internal crossovers to use them when the speakers were converted to active.