Gone active

Posted by: Marksnaim on 27 January 2016

After a couple of weeks hunting around I've managed to get hold of a Snaxo 2-4, HiCap2, Nap 250.2 and two 3 meters runs of Naca5. It took a couple of hours stripping everything down this afternoon but now everything is settling down nicely.

I had been considering changing my much loved IBL's but room constraints and WAF were making that difficult. I've had active systems in the past and fondly recalled what they brought to the party back in early 90's. With the number of good 250/2's currently on the market I decided to take the plunge. The total cost of this upgrade has come in at just over £2,000 which feels like the bargain of the century at the moment. Seen as a single upgrade (a package if you like) it's by far the biggest jump I've made with the current system. Far greater clarity than the passive configuration, voices sound more natural and stand out from the instruments to a greater degree and yet you can really feel the interplay between musician and singer. Bass has improved considerably too, more controlled, deeper and the notes are far better defined. Good old IBL's continue to deliver.

One odd thing though that feels counterintuitive; I can now turn the volume knob higher than previously, now just past nine o'clock whereas before for the same volume it would have been just below nine. Given that there are now 2 power amps I'd have expected if anything to have gone the other way. The other consequence is that watching the TV now really shows up the limitations of the BT Vision box feeding the sound. Not that I really feel the need for high fidelity replay of the Great British Charity Bake Off.

Posted on: 31 January 2016 by tonym

Actually, neither. The pots just alter the levels of each channel. The chap who I bought my DBLs from used them active with a two Pass Labs four-channel adjustable crossovers (two channels being redundant). How the dickens he managed to tune them I'll never know - using front pots you could alter slope, crossover and relative volumes.

Posted on: 31 January 2016 by Claus-Thoegersen

And I suppose the really odd tweak to remove the cover of the Snaxo also works on this model? It is easy to try out and free. 

Claus

Posted on: 01 February 2016 by AMA

TONYM> Actually, neither. The pots just alter the levels of each channel.

I do not get it. 

X-over is a combination of two HF/LF filters (passive or active) which cross over at certain frequency with two slopes (could be the same or different). 


Normally manufacturers fix the x-over point and only let users tweak the slope (same for both channels).

In my experience this is not very efficient method and if x-over point is not accurate than changing slopes will only move the sound sideway rather than better/worse.

If I can tweak the x-over point -- I get a much better flexibility to match my custom drivers.

If I can tweak both slopes independently -- even better, because drivers may (and normally do) have different sensitivity (and hence respond to the same slope differently).

Obviously, tuning up the x-over point and two slopes for two specific drivers is a routine work which can be only done in a professional setup (room and equipment). 3-way is the same but twice more work.

If one has very good ears he can actually tunes x-over manually (at least x-over point and average slope for both channels). 

I'm just curious  what is it exactly SNAXO allows to tweak with "pots". It looks more like a slope in my words ...

Posted on: 01 February 2016 by jfritzen

In my understanding with the Snaxo pots you adjust the output levels of the individual passbands (low/mid and high for the 242), ie the gain of the flat portion of the high and low pass filter curves. In the graphic the gain is at 0db for both curves, but your speaker or your room might require a small adjustment to sound just right. Crossover frequency and 18db/octave slopes are fixed. Afaik the crossover frequency can be adjusted at the factory.