Active Crossovers

[scott fitlin]

The Massenburg is a great piece. George Massenburgs stuff is all that good. Very transparent, clean, with amazing headroom.

Ive played with the 8200, its a winner, but, definitely not tubey sounding. Crystal clear, very precise, SS EQ! The outboard power supply for the Massenburg is outstanding, and + and - 24v rails are BEEFY!

FWIW, I dig tube EQ,s with both analog and dsp XO,s.

You couldnt really go wrong with any of the choices listed. You just gotta find whats " Soup Du Jour " for you.

[Guido]

I found this always very interesting.
Isn't it that these filters need to be tailored to the input impedance of the amp??

Yet, I'd still like to master the art of passive line levels...

Marchand makes a PLLXO (XM46) right out of the box.

Here is a quote from Phil:

"Because of the passive design the signal-to-noise ratio is very high. The noise generated by the crossover is much lower than for the electronic crossovers. The use of large ferrite pot-cores for the inductors is responsible for the low harmonic distortion levels. The circuit needs no power supply and is ideal for incorporating into other equipment, like power amplifiers, etc. We can also provide these crossovers assembled into a cabinet, with or without output level attenuators."

[Hoerninger]

I found this always very interesting.
Isn't it that these filters need to be tailored to the input impedance of the amp??

Yes, of course. Instead of 8 Ohms you have 10 Kilo-Ohms for example. (Output impedance must be considered as well.)
___________
Peter

[m8o]

Many thanks for the replies gentlemen. Was there talk of a DIY version of the Passlabs at some point?

I haven't heard that but you can check on the Nelson Pass forum on diyAudio.com:
http://www.diyaudio.com/forums/forum....php?forumid=8

I do own the original TaCT RCS which I use to bi-Amp my Martin Logan Sequel IIs which does a very good job, and the technlogy has advanced a great deal since that. Though the closest I have to an 'audiophile' friend prefers when I use an analog x-over.

I can't talk about what's best for tri amplification yet as I don't have the notable experiance others do that already contributed. The DEQX sounds great; like the TaCT I own but much better an newer. I'm undertaking a project where I'm tri-amping my Klipsch La Scalas up front, using 3 mini-Smiths from John W. with 2402 drivers for tweeters, + a mix of full-sized smith horns (for the center) and original K401 mid horns -- all driven by constant current amps of my design... I'll of course be actively crossing over. So I need 3 3-way x-overs. I'm insisting on time-alignment for the tweeters (and mid if it needs it), thus I've settled on digital due to the difficulty in producing long delays for the treble. This happens to be my 'short list' of options that I'm considering, in order of consideration:

http://www.groundsound.com/dcn23.html
in complete kit form:
http://www.groundsound.com/dcnkit.html

OR

http://www.xilica.com/products.html
specifically: http://www.xilica.com/docs/XMSERIES.pdf

There there's also a new Behringer coming out. Though that'll only address 2 of my 3 speakers I need handled, so that's not for me.

[boputnam]

There's also a new Behringer coming out...

[merlin]

M8o,

I'm glad to hear that the DEQX is better than the Tact. I used the Tact like you, and also like you, many friends who were simply music lovers preferred the system without any digital crossovers or dsp.

I like the simplicity of the PLLXO in theory - the lack of any active components or digital conversions. The answer will no doubt be to try all four options - but I'll need to get help with two!

Out of interest, a friend has been looking at these for those of us terrified of all things digital but intent on having some adjustability. Have any of you guys ever heard of them or tried the product? It sounds like a neat idea.

[eyedoc]

What is it you want to do??? You could Charge Couple the crossovers.

Rob

I have been reading (dangerous I know) about the increased efficiency and sound quality with external crossovers, and I am always interested in looking at improvements to the system. I have although, decided that I am probably out of my league at this time. Besides, it has been a few years since my undergraduate physics classes, and in fact, I lost my A for the second semester because the electro magnetic test kicked my butt. Oh well, I guess I will stay with optics... and go back to other projects...

[m8o]

Exqueeze me? I baking powder? [Wayne's World ] ...please elaborate "how"? Merlin asks about "high quality active filters" in the OP of which the said new digital behringer is. Please edjamacate me. (or is this implying "behringer" isn't "high quality" ??? )

[m8o]

M8o,
I'm glad to hear that the DEQX is better than the Tact. I used the Tact like you, and also like you, many friends who were simply music lovers preferred the system without any digital crossovers or dsp.

merlin, Big oops ... I don't want to give any false impressions. I meant the DEQX sounds 'better' then the TaCT "on paper" after reading the capabilities, specs, and comments about it. I did not mean to imply that I had heard it.

I found the Room Correction and subtle differences in the EQ curve I used with the TaCT (which I always based off inverting a measured RTA curve when using a 'flat' EQ curve in the TaCT) had a noticable difference in the 'cohesivness' of the music reproduction. Comments from the 'audiophile' -type friend aside, I still wouldn't give it up. Problem is one of my Audio Research Classic 150 monoblocks got burnt in a lightning strike, and I still haven't sent it in to get fixed, so I haven't used that system in years. ...I'm all about horns lately anyway tho, as you ca tell from my current project.

[Zilch]

There there's also a new Behringer coming out.

Link, please....

[m8o]

Link, please....

http://www.behringer.com/DCX2496/index.cfm?lang=ENG
http://www.parts-express.com/pe/psho...number=248-669

or am I mistaken and that has been out already, just delays in producing new units?

[boputnam]

...(or is this implying "behringer" isn't "high quality" ??? )

Behringer is simply not in the league of gear you are discussing.

In SR, I have been on the giving and receiving end of many Behringer gear - both as the FOH engineer and as the artist. There is nothing subtle nor sonically transparent about them. If we can hear it in the SR world, this is nothing you should consider in the audiophile space. I won't even use their gear in SR - I respect my audience too much...

Behringer do things at their price point, because they want to - no one competes at their "level".

[m8o]

Thanx. Noted. That's info is invaluable to know.

[Zilch]

http://www.behringer.com/DCX2496/index.cfm?lang=ENG
http://www.parts-express.com/pe/psho...number=248-669

or am I mistaken and that has been out already, just delays in producing new units?

Been out for several years, actually. It was discontinued for about a year in the U.S., allegedly because they failed to secure the necessary regulatory agency approvals prior to marketing here.

There seems to be an intermittent noise problem with them, the "Frying egg" syndrome, as yet not entirely resolved.

I haven't talked to Behringer direct about this, but it's on the list. I'm troubleshooting one sent to me by a forum member here....

[merlin]

With the Behringer, if you replace the analogue sections with audiophile components, drop in an off board linear power supply unit, fit decent WBT connectors all round, and bypass the DSP section completely, it can sound almost decent.