La Scala/Belle Crossovers AA AB AL-3

[DillonW]

I have two pair of La Scalas and one set of Belles, each have a different type of crossover. La Scala (1) has AA crossovers, it is the industrial La Scala with the K43 woofer, La Scala (2) has the AL-3 crossover, and the Belles have an AB crossover. These speakers make up my HT surround system. Would it be worthwhile for me to get all the same type of crossovers for them? I hadn't really paid too much attention to the crossovers till recently. I'm just looking for ways to get the best out of them. The AL-3s seem brighter than the ABs. The AAs are in the industrials. Please give me some insights.

Thanks!

[Randy Bey]

I would go with AA's throughout, but I'm not sure they play in the Belles.

There are probably many AA networks floating around the board, since the ALKs are so darn popular.

This is not a recommendation for ALKs however.

[Al Klappenberger]

DillonW

First and formostly --> Get rid of the stupid AB networks in the Belles! They stink in my book! AL networks aren't too hot either.

The AA will work in any of you speakers so they might be a good choice. A few mods will make them work pretty well. Of course, I recommend mine as best! (no surprise there I guess).

AL K.

[j-malotky]

Dillon

When I built my HT. I had Al build me a set of 3 crossovers for the front of my HT. My Khorns had AK in them originally. I put the ALK in my center first. It sounded good. About 2 weeks later, I replaced my mains AKs with ALKs the HT really came alive.

There is an advantage to having your networks all from the same family

I agree with both of the above. Go AA or ALK if you can.

JM

[CaptnBob]

Don't the Belles have a higher crossover point between the squawker and woofer than the La Scalas do? I would think that would limit how much crossover swapping one could do between the two.

[Al Klappenberger]

CaptnBob,

It would seem true that the Belle would need a different crossover, but PWK didn't think so. When I got my Belles back in 1976 they came with AA networks. All his big speakers had AA networks for a while. Khorn, Belle and La Scala all had AA netwroks. The reason is that the AA (like mine) are first order crossovers. That is such a slow slope that the horns own roll-off takes over. The horns cross over wherever they naturally want to!

Al K.

[edwardre]

According to Mr Al, 'The AA will work in any of you speakers so they might be a good choice. A few mods will make them work pretty well. '

Mr Al, I would be interested in a quick rundown of the abovementioned mods, if you have a moment. Thanks!

[Randy Bey]

The mods are as follows:

1) remove the wires (OK, just one is enough) from the Zener diode(s).

2) take the screw out of the squawker coil (the one with the little plastic frisbee in the upper left corner) and glue it down. Throw the screw into your junk drawer.

3) add another 4uF capacitance to the 2uF cap in the tweeter circuit. I thought this raised the crossover point but was corrected by Dennis, it just changes the characteristics of the slope.

I would add a fourth, optional tweak: bypass the woofer inductor. You can do this with a jumper wire on the barrier strip, after lifting the black wire going to the inductor. PWK said that adds 3dB to the woofer around 100hz, don't know if that's so, (I'm not saying PWK is wrong, I'm saying my memory might be), I took my jumper out a while back and put the inductor back in.

[Al Klappenberger]

Ed,

For more on the mods to the AA, see:

» Home Audio » » 2-Channel Audio » Difference between AL and AA crossovers

Al K.

[Trey Cannon]

If you have a speaker with a K-55-M mid driver you may not want to use the AA network on it...The "M" is a bit "hotter" than the "V". You may not like the change. The Belle started with the AA then went to the AB last to the AB-2. We are working on the AB-3 now...

The AA was crossed over a bit low, thus the change to the AB. There was no LF crossover in the AB, allowing the cabinet to roll the woofer off on the high end. Thus the AB-2 over all a much better crossover. Of course driver changes played a part in the crossover changes.

The La Scala with the AA prob. has a different mid driver than the PRO LS.

The 43 woofer will sound a bit different as well.

You can use the AL on the 33 woofer, but not the "V" mid...

IF you want them as close as you can, make the LS woofers the same, mid the same as well as xovers. On the BK use the AB-2.

If you need the schematics let me know.

[tubelion]

Hi Mr Cannon,

You said AB-2 is a overall better crossover, people in this forum usually think ALK or Type A is better.

Please elaborate your comment, and your comment is much respected because you are a insider.

I own a Belle with AB-2, I am buying parts to build a new crossover.

Do you have comment on the quality of the parts/ I ask this because I think only all the crossover designs built with similar quality can make a reasonable and meaningful comparison. For example, the popular ALK use a superior transformer, caps and coils etc, it should be better than type A or AB2, but not necessary better in the way of design.

I am going to rebuild the crossover with best parts anyway, it is the respect to Mr PWK and Klipsch , and see how far can the sound be improved of the classic, but I have get the information to decide which design to go first, for example, I can rebuild the AB2 with best parts if you can further elaborate your claims. I shall post the result to all who is the same confused by the mestery of crossover.

I understand the design of crossover by klipsch is changed because more customers use high power SS amplifier. I use high quality SET amplifier, so protection of the tweeter is not my concern.

Thanks with best regards

SZE

MSB platinum plus CD player

First sound preamp

Jadis 300B Mono

Belle

[Guy Landau]

Tubelion,

You can have more crossovers info by searching threads on the 2-channel audio .

[tubelion]

Hi Guy,

I have seen them all, trust me I've worked very hard.

I shall try them one by one, likely type A first.

But the commment from Cannon is new and he is the klipsch technician, it would be great to listen to him.

I think, until proven otherwise, same quality of parts is essential for a meaningful comparison of different design. In this aspect, no doubt the ALK design has taken the advantage to be fair, I am going to experiment that. Now I only need one or even two pairs of transformer.

I have contacted the universal transformer, even with the help of Randy, they don't yet reply for my request to sell and ship the 3619 to Hong Kong in one month time. otherwise I would have posted my findings.

regards

SZE

[Randy Bey]

SZE,

they still haven't sent you the pricing info? He said he would fax it to you that afternoon.

I will call him again and see if there is a problem.

[Guy Landau]

Tubelion,

You can try and use the T2A transformers from your Belle.

Trey Cannon probably knows what he is saying but do remember that for the last 30+ years,Klipsch had designed the crossovers for higher powered solid state amplification and soundwise he prefered the simpler type A and since you are using the Jadis 300B monoblocks the type A may suit your system better.

I would like to clarify that I am not trying to bring AL K into closing his business and have enjoyed his crossovers for more than 2 years.I have just found a crossover (type A) which sounds better to my ears and matches my system/speakers/taste in a better way.

[edwardre]

Tubelion wrote: 'For example, the popular ALK use a superior transformer, caps and coils etc, it should be better than type A or AB2, but not necessary better in the way of design.'

Tubelion, I think that Al's 'claim to fame' as it pertains to enhanced networks designed for several Klipsch Heritage speakers lies with superior design. The fact that he uses, and suggests using superior components is more or less a bonus......

[tubelion]

Dear ED,

It is possible or likely ALK's design is a better one, I am not saying no. I just get the impression from my search that few comparison was done in my so-called fair setting with same or similiar quality of parts, despite so many reports were there in the forum.

By the way, do you think my suggestion is a fair one and worth doming? or you know someone had done the comparison in this way before giving their reports.

As an audiophile, I will find out the truth with sincere respect to all. I always enjoy hearing good music and the process of experimenting how to improve it.

Best regards

SZE

[DillonW]

WOW, thanks for the overwhelming response. Klipsch nuts are the greatest!! I had honestly considered the ALKs based on feedback posted on this board, BUT... needing six of them make it a bit cost prohibitive. Picking up four more AAs seems a little more realistic. I do plan on replacing the K-43s so all woofers will match. Interesting mods for the AAs I will have to begin experimenting.

Thank you all VERY much!

[edwardre]

Hello Mr Tubelion...."yes"...I have great respect for your approach. I do not believe that I have read of anyone replicating an AA with all high end parts and comparing with stock. I for one will be very interested in your results as I have great admiration for the AA, especially for some of the qualities that cannot be adequately put into words.

I was simply offering my view on Al's nets. From what I've read here on this board as well as personal communique, Al places a great emphasis on the engineering aspect.

For the record, I would just like to say that PWK was THE MAN. Especially in the early days...'40's - '60's. We all spend hours and $$'s trying to improve upon his nets. Simple mods to full on replacements. But the fact is we're all building upon a truly unique thing especially in relation to what other mfg's were offering. Last week I purchased a vintage University xover. An N-3. Looking through my '50's University catalog, this was the top of the line. I received it yesterday. Very nice looking closed box unit. Stellar baked enamel forest green heavy box with a fine brushed brass faceplate, sporting 2 control knobs, also with brass faces. A real 'looker'. I naturally had to crack this thing open to check out the goods. What a POS. 2 leaky cardboard caps and 2 minute transformer looking things. Just for giggles, I hooked it up, replacing a Klipsch network. The resulting hodgepodge of noises was so substandard to the Klipsch net of the same era words can't even describe. I was completely embarassed for University. Likewise, I have a pair of late 50's Jensen xovers. The good ones used in their very positively lauded 'Imperial'. I can't crack these open as they are like sealed in a black epoxy-type resin, as if a big secret lies within. But I can and have hooked them up. PU. Weak. Not anything that I would ever consider using in anything.

PWK was a true pioneer.

[tubelion]

Dear Ed,

Thanks for your encouragement to try on a fair basis comparison.

From the research I did, someone had experiemnt with cheaper part like solid coils without sucess in the ALK design, best air core is strongly suggested by Mr ALK.

So it further consolidate my thought that if ALK design demand best quality parts to avoid produce poor sound, it would be unfair to ask for a type A design with usual grade parts to produce good sound.

The second fair setting would be ALK against Type A both with usual grade parts, right? Of course I unlikely do it, but it can be easily done with little cost.

I am still waiting Mr Cooper 's answer to my mail for the 3619. Thanks again Randy, I will wait for one more day before asking your help. maybe Cooper is busy.

Thanks

SZE