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Tony
09-14-2007, 09:52 PM
Hi Hello,
I have a pair of Century Gold LE which I shall shortly be bi-amping. I am wanting to go 'active' but I am unsure of what electronoic crossover to employ. It seems that to some extent the passive crossover remains in operation for HF as there are only two connectors - LF and HF.

Does anyone have any experience of taking Century Golds active, or, does anyone have any help they can provide? I have Naim 72 Pre-amp and 2 x Naim160 power-amps (stereo) with HiCap. I am wondering whether the Naim Snaxo 2-4 would do the job powered by another HiCap.

Any help and advice would be very much appreciated.
Tony.:)

macaroonie
09-15-2007, 04:36 AM
JBL M552
As I remember it the Naim x/o does not really allow much adjustment and is tailored to Naim speakers

Tony
09-15-2007, 02:33 PM
Thank you for this - I'll look into the M552 and I wonder if it's still available from JBL.

Re Naim - that is what I think, but I cannot get definite information.

Does anyone have any other suggestions as to active crossover's I could use?
Has anyone in the forum gone active with Century Gold's?
:)

macaroonie
09-16-2007, 10:38 AM
Just had a look and snaxo is no good for you. it is also £1050 and as far as I can see non adjustable. Naim are not big on handing out data but the filters are 18dB/ oct
M552 is not made any more but they do pop up on ebay at about 150US.
There is also the other JBL pro unit 5234 which can be tailored for your system.
Put a WTB message on the wanted section, someone will have one and not at silly money.

hjames
09-16-2007, 10:42 AM
Thank you for this - I'll look into the M552 and I wonder if it's still available from JBL.

Re Naim - that is what I think, but I cannot get definite information.

Does anyone have any other suggestions as to active crossover's I could use?
Has anyone in the forum gone active with Century Gold's?
:)
Got my M552 off ebay for just over $100 US last year - VERY flexible - I'd recommend one ...!
Check it out - the manual is here - http://www.jblpro.com/pub/obsolete/M552%20Owners%20Manual.pdf

I originally used it for my 2 ways (L200s) with a pair of amps, then moved the system to the 4341s I now have. Very nice.
But - as Bo might say - what kind of test gear do you have to set it up for your listening space?

Tony
09-16-2007, 12:08 PM
Ears - do I need special set-up equipment?
Or am I showing my ignorance?
I am no techi

macaroonie
09-19-2007, 12:58 PM
Your speaker tech sheets will tell you the x/o frequency and the 552 has adjustment over quite a range however the front panel is calibrated so as long as you stay within say 10% of the desired frequency you will be ok. You also have individual gain control over each output ( low and hi ).
Just dont do your fiddling at full whack.

Tony
09-19-2007, 02:37 PM
Wouldn't you believe it - the very day before you suggested the M552 one sold on Ebay for about $86. Hopefully one will turn-up soon.:)

Tony
09-19-2007, 05:43 PM
Hi Macaroonie,

Thank you for your help. Elsewhere it has been suggested that the DBX223/234 would suit my needs. It would seem that the XLR version is the better option, but all models are readily available new on Ebay for reasonable $$$ about $130. (I have dug-up a source in Hungary for a supposedly new JBL552 for $550 - but, but .....)

I would value your thoughts (and anyone else's).

Also, where would I introduce the active xover into my system and what connectors will I need?

I have a Naim'72 pre-amp into Naim Hi-Cap into 2 x 160 Naim power-amps.

That's the problem with breaking the Naim regime - going into Naim speakers would be a doddle with a snaxo etc - but I like my JBL Century Golds which are singing pretty at present bi-amped passive but I want to try the active option.

:)

Tony
11-23-2007, 12:18 AM
Having waited an eternity having the necessary interlinks made, I went 'active' last night using a DBX234XL crossover after having progressed through bi-wire and bi-amp - with all three progressions bringing an upgrade.

While using the external electronic crossover does not bring you fully active insofar that presumably the passive crossover still operates between the mid-range and high-frequency, it seems to me to have smoothed-out a slight harshness I felt existed previously with the high-frequency transducer.

At the moment I am a little timid with my 'twiddlings' but it certainly seems that using an active crossover has deepened the sound stage which at the same time has become more focussed, clearer with greater separation - very engaging. In fact I was up half the night riffling through my vinyl!:)

Tony
11-24-2007, 12:25 AM
To update or correct my last post, I have gone active by switching the crossover to the bi-amp position (or in my case leaving it where it was) and have inserted the DBX234XL crossover. This is sort-of halfway way active because the passive crossover is still there but LF is only fed minus 600Hz instead of receiving the whole range and wasting power having to dump the HF; Likewise the HF is only being fed plus 600Hz and does not have to waste power dumping the LF. Or, this is what I think is happening!
Whatever, just this has brought a significant upgrade in performance, with more uplift to come I think if I can move to fully active.
Has anyone any experience of taking Century Gold's fully active, or, any advice as to how I can bypass the passive crossover altogether without having to mutilate the cabinets?
All suggestions gratefully received. :)

djgaloot
11-24-2007, 10:05 AM
I believe you can use frequency equalizers for this and fine tune what frequencies and how much to attenuate/boost. I am considering this route with my Altec Malibus down the road a year or so.