JBL XPL-200 and Rane AC24

Has anyone had any experiences with Rane's AC24 Active Crossover or any of Rane's active crossovers? Supposedly they're on or very close to the top for active crossovers for professional and home theatre.

At the moment I am trying to source some XPL-200 input/output cards for my DX-1 crossovers with no luck and so I am looking at other options in connecting up XPL-200 speakers to an external active crossovers.

Since the XPL-200's are a 4-way setup with two sets of binding posts, one for low and the other for high, I have been thinking about re-wiring the speakers so that each driver has its own set of binding posts and then use Rane's AC24 crossover to drive of the drivers in the 200's.

By using the AC24 crossover, I should be able to gain complete control of how each driver performs in any room scenario. I know the DX-1 from JBL does not have anythin near the prgrammability of Rane's AC24 crossover plus the AC24 incorporates the latest technology out today.

The DX-1 is classified as a classe "A" pre-amp but it would be intersting to see if there are any comparison's between the DX-1 and Rane's AC24 crossovers.

I will attach some info on the Rane so you can decide for yourself.

Any thoughts on whether or not this project seems a reasonable one to pursue?

Hi Pasadena

I'd stick with biamping, using either 12db per octave LR or Butterworth slopes. I haven't yet analyzed the stock XPL200 schematic so I don't know what slope type was actually used or realized.

The project you mention, while interesting, most likely ( because of the steep slopes Rane uses ) will just result in a breaking apart of the existing coherency achieved with the existing driver/crossover combination. This will certainly change the "voicing" of the whole system. Additionally, the 093ti mid gets a bit of EQ from the circuit ( in a LCR form ) that you would need to maintain. It does seem like a lot of work ( & investment in amps ) for an unknown return.

IMO; Biamping will give a lot of bang for the buck ( by keeping th LF wave-forms from muddying up the rest of the band-pass ) . I think going beyond that gets into diminishing returns from investment, pretty fast.

If they were mine; I'd first consider ( after biamping ) modifying those passive crossovers with different/upgraded components ( or more likely building whole complete new portions to accomodate charge-coupling my choice of caps ). Whether that would result inan improvement would also be questionable.

Also, I'd recommend you persevere in your quest to get blank cards for those DX-1 crossovers. Or maybe get some blanks made up. Also, I'm pretty sure there are kits for building DIY circuit-board cards ( along with acid etching compounds ) .

just some thoughts <> Earl K :)

Say; just what is it about the present setup that you feel is lacking ?

I too am a huge (need to go on a diet) advocate for biamping. All three of my stereo systems and my HT system are bi-amped. It can clean up the mid range and it certainly gives additional flexibility and control in setting up the system.

I have crossovers from Rane, Audioarts, Symmetry, Jeff Roland and I used to have the Dahlquist active crossover. The Rane and Audioarts are pro models, the other three are medium to high end home designs.

In reference to your query about Rane. I own the model 22 and 23. I have no experience with the model 24. Both of the Rane crossovers that I have and the two different Rane EQs I have are not great for critical listening. (I use them primarily in my HT.) I would not recommend them if you have the budget to get something better. If you do a search on this forum for "Rane" you will undoubtedly find several references to posts that I have made ripping on them followed by my recommendations and those of others.

Widget

Hey Widget,Whats your opinion about the Audio Arts?I liked em years ago but it been so long that I am not sure what todays expectations would be.They could probably benefit sonically from recapping them.Oldmics

I used to rebuild the old audioarts crossovers ( and their 5200 series Dj mixers ). They were simple types copied directly from the generic opamp schematics as found in the national semiconductor handbooks.

The type was state variable, 12db. The chassis / power supply / grounding schemes left a lot to be desired but that was all that was available to the budget club install market in the '70's...

A better built model from that era was the urei 525 - it was 18db ( constant power in the passband ) and used MUCH better components.

If you really want control, get a new generation DSP model from the highend pro companies ( such as the BSS omnidrive ). These allow infinite filter combinations with delays, gates and EQ's with much lower noise floors and better software control.

As much as I prefer analog, one of these units would replace (3) 6 foot tall racks FULL of limiters, gates, crossovers and EQ's...if you added up the noise floors of the individual components, it would be a LOT more and would require a doctorate in engineering to optimize the gain strutures.....:)

sub

Quote "If you really want control, get a new generation DSP model from the highend pro companies ( such as the BSS omnidrive ). " Have you seen the Lake Technologys,Contour D.S.P.? Were waiting on a pair of units to be delivered.My heads still spinning from that demo at A.E.S. Slope capacitys of 200 db per octave.Thats just nuts.Oldmics

You guys are now talking sound reinforcement. While good equipment makes a difference in that arena as well, it is a different world from what I was talking about. I was talking about critical monitoring or high resolution two channel home audio. In this world with the possible exception of the (very expensive at about $100K for the complete system) Meridian equipment, I have yet to hear a digital system that I thought had high enough resolution.

As for the Audioarts, it is still decent. Not exceptional and only marginally better sounding than the Rane gear. I would agree that the Urei is superior, as is Klark Teknik, Bryston and others.

Widget

Dunno how it compares with things, but a friend of mine has been making great use of a Madisound Sledgehammer 24x4 3-way electronic crossover, in his tri-amped mega-system (per side, 3 12" Eclipse subs, 4 8" Madisound Sledgehammer midbasses, 1 Focal 7" polyglas mid, 1- Seas tweeter... all running from a big Cinepro 3K6SE amp, 400w x 6). It's very close to noise-free... no hiss, no discernable grain or loss of detail, AFAICT...

Regards,
Gordon.

Earl K,

Thanks for your reply and an interesting one. I have attached a crossover schematic for the XPL-200's so let me know what you think? It's a JPG file so the numbers might be a bit hard to read but I have a pdf version, which is much better to view. Let me know and I can send it to you?

I'm only just starting up my system but so far I have a pair of B&W 801 Matrix Series 3 speakers hooked up to a NAD 208THX amplifier using a Denon 1803 as a pre for the 208's. I use a Denon DCD-300 CD Player but looking at replacing this with Denon's DCD-S10 MKII CD player, which I want to mod (another project). I am also looking at replacing the 1803 with a pre-processor amp and had Lexicon's MC-1 in mind until I found out this unit doesn't support XLR inputs (back to the drawing board).

"Where does JBL come into this so far", you ask?

Well, I'm going to buy a pair of JBL XPL-200 speakers (I already know where to get a pair from) and I already own two JBL DX-1 crossover kits, hence my quest for 2 sets of XPL-200 input/output cards.

My aim is to bi-amp the XPL-200 speakers using 2 x NAD 208's to run the low end and one other amp to run the high's, which I currently haven't found. As you can see I'm in the hunt for a second NAD 208 and a single high frequency amplifier, all linked via XLR. Any ideas on what is a good high frequency amplifier to compliment the 208's or a good/exceptional high frequency amp in general (must have XLR's)?

When I first heard the B&W 801's 4 years ago, I fell in love with them straight away ánd it wasn't till mid this year that I eventually found my 801's. Having said this, late last year I was working with a friend of mine who told me about JBL's XPL-200 speakers and how great they were. He went as far as saying that the 200's were the best speakers he's heard thus far and said they were even better than the 801's.

I thought this wasn't possible for a speakers that stopped production some 11 years ago but I decided to do some research on the 200's. Sure enough, from all the reviews I read around the trap and from people I has spoken to had put the XPL-200's in a class of it's own, eating the 801's for breakfast (That's with the XPL-200's using the DX-1 crossover).

So, ever since then, having never heard the 200's and going by someone's opinion, I went on a mission to find pair of XPL-200's. I also read about the much sought after DX-1's that was made for the 200's so I was hell bent on finding these as well, which I did but with no cards....Anyone out there have any spare cards?

During my search for the 200's, I stumbled on an ad on the net selling a pair of Matrix Series 3 801's. I jumped at the oppurtunity and bough them. Being such a rare speaker to find in Australia, I imported this pair from New Zealand....such is my dedication and "Yes", they did weigh a lot. :)

Now that the Aussie dollar is a lot favourable than it was 4 months ago, buying stuff overseas seems so much more attractive. :)

My aim is to audtion the 801's and the 200's in a so called shootout, see what the results are. If I have both of these speakers, I don't think I can afford to keep both of them so whichever wins the shootout, will be the ones I keep. I'm partial to the XPL's but I'm going by what I've read so until I have the real deal in front of me, only then will I experience the truth. Even if I do have both speakers, I don't think I would want to part with either of them.

I suppose I just want to listen to my music being delivered in the best possible way but maybe I'll wait until I get my XPL-200's and input/ouput cards and all my other amps and so forth before making a judgement. I suppose I'm just too eager to find what I want. :)

Hi Pasadena

I have the schematic and Operators Manual for the DX-1 - so no need to post them on my behalf. I took a look at the available info .

Quote:

---

Well, I'm going to buy a pair of JBL XPL-200 speakers (I already know where to get a pair from) and I already own two JBL DX-1 crossover kits, hence my quest for 2 sets of XPL-200 input/output cards.

---

Why two sets ( 4 cards ) ? - you only need 2 cards per DX-1 to biamp a pair of speakers (each card is a 2-chnl HF card type or 2-chnl LF card type ) .

So the two DX-1 crossover kits that you own, have no crossover cards installed in them ? Too bad because if they were in there, an option would be to remove the resistors and caps in the present cards and put in the appropriate value caps and resistors for the XPL200. The HF card has 12 parts in total ( 6 per chnl ) to change while the LF card has 20 parts in total to swap out.

JBL should be able to provide the formulas to you for calculating the necessary values of R & C - to get the model specific slopes one obtains with this crossover. Then your next mission would be to source those parts. The DX-1 manual mentions that "special 50 volt NP electrolytics" are used in these HF cards ( bypassed with polystyrenes ). I'd ask JBL what "special" really means and whether or not "Polypropylene"caps could be used instead. According to the XPL200 Operators Manual the biamp crossover point is set at 250hz in the DX-1 ( not the 300hz of the internal passive crossover ).

As you stated, you first want to solve your crossover / amp dilemma before starting your comparison process - but isn't there a danger these 200(s) could disappear in the meantime ? If it was my dilemma, I'd buy them now, solve the DX-1 riddle later - & if necessary use a 5234a or 5235 for crossover/biamping duties ( lots of cards or info is available for modifying these cards ). From my reading of the schematics , the "personalizing" of the DX-1 to the speaker type happens in the LF drive portion of the crossover card. Each LF portion has an opamp that can offer LF tailoring through different R & C values in its' feedback loop. That's as technical as I can get. I'd ask others who use 2214h woofers whether or not they felt this speaker needed much high pass compensation/tailoring to sound good or is it nice as is. I'd get on with the evaluation process and not get hung up by the DX-1 configuration problem. I highly doubt that JBL put all their marketing eggs in the one DX-1 basket. They obviously spend a lot of time getting their passive crossovers fine tuned . I'd start the comparison process with both speaker types in passive modes and then move it up a notch to biamping if the XPL200 passed the first hurdle. I think any reasonable quality 2 chnl / 12 db per octave , crossover will enhance your determinaton process. Again, I feel it's biamping that offers the obvious sonic advantages and more than likely, way back in the sonic race, any "personalizing" the DX-1 offers the 2214H woofer.

re; your question about HF amps
I own Bryston 2B-LP amps - they are used to drive 1" compresson drivers in speakers for my small SR company. I listen to one of these here at home because I like to keep my listening experience directly related to what sonics I impose on others. Having said that, I do find it's a nice sweet sounding amp for up close and personal listening.

my 3 cents worth of opinion <> Earl K :)

I still have a pair of the 200's little brothers - 140's - in the basement. Before the L250's arrived they were the top dog in the house. I agree with what's been said here - GET THE 200's NOW and worry about the active crossover later. The XPL series has a very good bi-ampable internal passive crossover which may slow down your quest for an active one once you hear just how good these speakers are. You may (should) consider something other than the NAD for the high end - tubes would be my first choice. And you'll want lots of power for the lows. I was using a 250w yamaha PC2002 for the lows and could have maybe even used more.

Let us know the results once you've gotten them in house....


jblnut

I certainly wouldn't let a DX1 issue stand in the way of pressing the XPL200A's into service. Use them full passive for now.

It appears the list of values for the XPL200A/DX1 card is missing.
I would need to re-calculate the values using the voltage drive.
I don't know when I will have the inclination to slog through that.
You'd probably be better off continuing the search for the cards. Maybe someone else who owns a DX1 and XPL200A's will eventually see this and be so kind as to post the values on their cards...

Earl K,

The reason I'm after two sets of cards because I have to DX-1 kits. I bought two because initially I wanted to use one DX-1 per side, keep the cables short theory but also down the track, if I were ever to find a second pair (heaven), I'd use the second with the second set of 200's as the rears.

I'll definitely keep the NAD 208's for the low end as I think they provide more than enough power and soniq quality but I will agree that sometheing exceptional will be needed to drive the high frequency side of things. I have attached a spec sheet for the 208THX if anyone is interested in some light reading or use its data to match it with some high frequency amps.

I have thought about tubes but I've read a lot articles where tube and solid state amps together cause phasing issues in a bi-amped scenario. Hence my inclusion in my orignal post about using an active crossover such as the rane which has a lot of programmability to correct phasing for such cases. Like you guys have mentioned, there are other active crossovers that will do a better job. Has anyone used Bryston's 10B crossover?

The only reason why I'm holding back on the 200's here in Australia is because I think they're very over priced for the Australian market. Then again, we're talking about Australia where we receive the last of anything technology wise and we get charged like a wounded bull. Plus, the 200's here in Australia is not in top condition.

As a matter of fact, with the Australian Dollar being the way it is, it's actually cheaper for me to source a pair of 200's in the U.S and have my friend in Utah send it to me. Including shipping, it's still way cheaper than those 200's here on the other side of my country.

I know, sometimes beggers can't be choosers but I like to make sure that what I get for my moey is in excellent condition///that's me. I'm thinking hard about it.....those 200's here in Australia are probably the only ones in Australia and I have been posting around the world looking for them. The same goes for my quest of the DX-1 input/output cards.

I agree that I should get the 200's and do my comparisons with the B&W 801's and go from there.

Cheers
Pasadena

I have included some pictures of JBL's DX-1 external active crossover - Front, back and circuit board, which will be of interest to most.

If you require a more detailed pic of the circuit board, I can e-mail it to you.

JBL DX-1 Front

JBL's DX-1 circuit board.

If you already haven't noticed, the voltage has been modified from 110/120v to 220/240v using the DX-1 schematic that's in circulation.

JBL DX-1 Back.