New improved Universal ALK network Version 6

[Hardhead]

I had the same experience as jwcullison. When I replaced the Solen 6.2 uFd and Harmony 1.0 uFd combination of capacitors with Auricap 7.2 uFd capacitors that I had special ordered, I noticed an improvement in the tweeters' (K-77-M's at the time) clarity.

When I replaced the Solen 39 uFd Solen and 1.0 uFd combination with a pair of 20 uFd Auricaps sometime later, I didn't notice a difference (and I wanted to after paying $$$ for the Auricaps). In all fairness--and in defense of my hearing--I will say that I didn't then and don't now push the speakers hard, never more than 95 dB, so the ALK's never had a chance to "open up" as Dean says. They do sound great, nevertheless.

Dean, sorry I hurt your head, too.

[Al Klappenberger]

Guys,

One of the very first people to get the "ALK" network replaced the 6.2+1 uF bypass with a 7 uFd Hovland also noticed no difference. That particular cap is the least important of all so that didn't surprise me. The 39+1 uF combination carries everyhting and replacing those should make some difference.

Al K.

[jwc]

Al. What you and Dean are saying about the importance of that primary cap "carrying everything" makes very good sense. Theoretically, that should be where the money goes.

I am not disagreeing but find it interesting how sometimes what seems to be very important theoretically or objectively doesn't end up being as important as one may think (at least to some ears).

When I was goofin around with testing of my dbb's for the first time, I had Type A's in them with a duplicated lowpass filter to accomidate the two woofer design. I started out with a 13uF midcap and a 2uF tweeter cap. Both were Solen fastcaps.

When I realized that that network would work, I stuck a 2 uF Theta F&F in for the tweeter and left the 13 uF Solen there. The tweeter is a JBL2404 by the way. I DID notice an improvement with tweeter sounds. Now when I replaced the Solen 13uF with Theta 6uF and 7uF in parallel, I would have to talk myself into any difference. That Solen 13uF is little and cheap. That 6 and 7 uF Theta is big and very expensive. I was dissapointed and perplexed at the same time.

I would agree that the midcap would make the most difference but I couldn't notice it. I find it weird that the tweeter filter "slaves" off the midcap and I got subjective/noteable results with the change of the tweeter cap only.

Now I did the same type test with a Type B network. Interchanged Theta caps for the tweeter and found the same results (K77 this time). The Theta sounded better than a Solen or Bob's cans. However, changing around the mid caps didn't make much of a difference. Go figure. Maybe its my hearing.

jc

[Deang]

Maybe what we really need is an air core autoformer:)

[DizRotus]

DeanG wrote: "Maybe what we really need is an air core autoformer:)"

That's a great idea, made from #14 Litz wire it would be about the size and cost of a Buick:)

[Hardhead]

I completely agree that upgrading the 39 uFd Solen and 1 uFd Harmony combination will make the biggest improvement in the overall sound of the speakers, but I think I understand the reasons for what I heard--and didn't hear--based on the sequence of how I upgraded my speakers. I upgraded the tweeter capacitors, then the midrange/tweeter capacitor combination, and then the ALK Trachorn. Had I done that in the reverse order, I believe what I heard would have been more logical.

An audio component/driver/horn/etc. can't reproduce sound better than its physical and design limitations allow. In other words, if a quality-limited component is already reproducing the best signal it can, given its limitations, improving the quality of the signal upstream of that component doesn't result in an improvement in the ultimate overall sound.

I suspect that the K-400 midrange horn was the weakest link in my system and was playing as well as it could, given its limitations, but not equal to the quality of the signal the 39 uFd/1 uFd combination was sending it. Upgrading the 6.2 uFd/1 uFd capacitor combination going to the tweeter with a 7.2 uFd Auricap resulted in an audible improvement in the highs because the signal going through the 39 uFd/1 uFd was already pretty good--better than the K-400 but not better than the tweeter.

Later, when I upgraded the 39 uFd/1 uFd combination to the double 20 uFd Auricaps, the K-400 simply couldn't play the improved signal any better, given its limitations, so I didn't hear any difference. Then when I upgraded to ALK's Trachorn, I credited the the better horn with the very audible improvement that resulted, but part of the improvement was made possible by the better capacitors from the midrange/high upgrade.

The moral of the story is to identify and upgrade the weakest links in your system in the proper order, or you can be misled.

[3dzapper]

Zeq = Z1*Z2/Z1 + Z2

That equation may have something to do with the failure to hear a significant difference when replacing the 39/1uF combination. Although the signal sees the two caps as a single 40uF block to the low signals, the higher signals see two different reactances. That current will seek the path of least resistance/reactance. In this case the 1uF Hoveland.

Since we are already dealing with a high quality sonically superior capacitor, it would take a quantum leap to apprecially alter the sound.

In the tweeter filter, the reactances are much closer between 6.2 and 1uF than 39 and 1. That may mean that in this combo, we are "hearing" more of the Solen's signiature.

I may be wrong, have been before, and will be again but, that is the basics of the arguement for bypassing.

Rick

PS. I am omitting any "smearing" from phase angle anomolies.

[jwc]

Damn Rick. Whether your explanation is wrong or not.....I like it.

jc

[J.4knee]

Al,

Any plans on offering an "updated" parts kit for those of us with the previous versions?

[chops]

As to a 4500 Hz crossover version, I did a post here on the forum about how the DIY builder can make a 4500 Hz version. I really don't want to offer a 4500 Hz version myself becasue it's nothing more than a crutch made possible by Bob's new tweeter to get around a bad squawker horn (K400 and K500). The RIGHT answer is to upgrade the squawker with my Trachorn or an Altec VOT horn and leave the crossover where it is. I think a good squawker horn will do a better job of reproducing a midrange extended to 6000 Hz than asking a tweeter to do it. If you want the "best" you want my network crossed at 6000 Hz and a better squawker horn. If you want to retain a marginal squawker just becasue it there, maybe you should go for one of Bob's clone networks with the extra coil crammed on top of the existing one.

Al K.

That's fine and dandy, but have you heard the 4500Hz mod? Bob's solution for a lot less than $50 is a big improvement.

Not everyone has $575+ for a pair of networks, and then another $300 to $600 for Altec 511B's or your Trachorn. Just for those networks and horns alone cost more than my CWs new!

Whether the 4500Hz kit of Bob's is a crutch or not, it gets the job done, and gets it done well.

Just my $0.02...

[Al Klappenberger]

Chops,

I agree that not everybody will want to spend big bucks on a crossover network. I am simply here for the people who want no compromisis and will pay for it. If you want to save money you get a simple clone network and add the additonal coil. Just remember that you get what you pay for! Not everybody will buy a Ross Royce when a Chevy will get you where you are going for a lot less money.

AL K.

[Al Klappenberger]

J.4,

No.. I would not want to do a cap replacement on a finished network. It would be a hack job! If you really want to do that, the parts are available from the same source I get them from. Dean Wescott has made cap mods on my "ALK" networks. He may want to do it for you.

Al K.

[chops]

Chops,

I agree that not everybody will want to spend big bucks on a crossover network. I am simply here for the people who want no compromisis and will pay for it. If you want to save money you get a simple clone network and add the additonal coil. Just remember that you get what you pay for! Not everybody will buy a Ross Royce when a Chevy will get you where you are going for a lot less money.

AL K.

Al,

Actually, I was referring to more of what one can afford rather than what one wants.

Sure, I want an all original 1967 Aston Martin DB6, but all I can afford is a used 2002 Mazda Miata.

If I was making the big bucks and wanted to buy your networks, I most likely would, but since I don't, I can't, so I won't.

Yeah, I'm probably missing out not using your networks, but what I don't know won't hurt me, right? []

Charles

[J.4knee]

Al no I would do the work I built the networks from your kit. Anyway I don't see how that would differ from repalcing a failed cap or other component in such an instance. In that case IMO one would not repalce an entire network in lieu of a simple repair. I do this and a good deal more for a living on combat systems equipment Navy ships. What I was referring to was the fact you match the caps you put in your kits and networks or more to the point would you make matched sets available? I lack the requisite equipment at home to match caps or more importantly I don't want to have to order more caps than I need just to get a matched set. Anyway you answered my question thanks.

[meagain]

Yeah, I'm probably missing out not using your networks, but what I don't know won't hurt me, right? []

It's what I don't have that curiousity drives me nuts. I'd like to hear one of these things! My goodness - are there no other people in Chicago with khorns or LaScalas?

[Al Klappenberger]

J.4,

I might consider supplying matched sets of the Sonicaps. It would help in keeping the volume up. I will have to spend over $800 on the Sonicaps alone before I build another set of the upgraded version 6. This is the price of the minimum quantity to get a price break. I usually match them to within 1% of each other. If you buy them in low quantnty the variation could be 10 times that.

Al K

[J.4knee]

J.4,

I might consider supplying matched sets of the Sonicaps. It would help in keeping the volume up. I will have to spend over $800 on the Sonicaps alone before I build another set of the upgraded version 6. This is the price of the minimum quantity to get a price break. I usually match them to within 1% of each other. If you buy them in low quantnty the variation could be 10 times that.

Al K

OOOOH Al,

Please let me know if you choose to do that!

[meagain]

J.4,

I might consider supplying matched sets of the Sonicaps. It would help in keeping the volume up. I will have to spend over $800 on the Sonicaps alone before I build another set of the upgraded version 6. This is the price of the minimum quantity to get a price break. I usually match them to within 1% of each other. If you buy them in low quantnty the variation could be 10 times that.

Al K

I had no idea caps can have variances between each other. Like matching nos tubes? So are you saying that if you buy them in quantity, you're ensured of buying a 'run' where the caps would be more similar to each other and buying here & there - there is more risk in them not matching as perfectly? And - if you have more of a mismatch of caps between 2 crossovers - would one perhaps hear a difference between the 2 speakers - and that would be a distortion issue?

[Al Klappenberger]

Guys,

Yes. Capacitor values will be within a specified range. A 24 uF +-5% capacitor could actually be anwhere between 22.8 and 25.2 uF. If you buy just two, the values of the two could fall at the extremes and you will have a 10% match. Chances are they will be much closer than that, but if you measure a pile of them and sort them lowest to highest you will get matched sets of two. If you have two in parallel to make 48 uF, like my new woofer filter requires, you match 1 with 4 and 2 with 3 as you go down the list. That makes the matching extremely close. Matching like that yields a better stereo image becasue the insertion phase will be more equal between the two netwroks, left and right. It's left to right phase and amplitude that the brain uses to "compute" the direction a sound is coming from.

BTW: If you look at the picture I post to begin this thread, you will see the measured value of the two 24 uFd Sonicaps written on them. These were measured by the manufacturer so he could supply me with the needed matched sets in a quantity of 4. They may do that matching for anybody. I'm not sure if there is an extra charge. I paid list price for them the first time even though they were samples for quantity orders later.

Al K.

[psg]

The Solen F&F are a good value. Of course, by the time you pay the brokerage fees to have them shipped UPS Ground from Canada, the price difference between those Solens and the Hovlands is only a few dollars.

Sounds like what is good value to those of us in Canada is different than what is good value to you. It makes little sense to me to buy a crossover from the US whose parts came from Canada. Two border crossings inflates the prices. It would be great if you guys had kits for us that excluded parts originally from Canada but included a parts list from Solen or PartsConnexion.

Or do only Solen caps come from Canada?