My first La Scalas

[mboxler]

[billybob]

Think most could care less about a crossover network.

Others whether serious or just owners like to experiment. 

Some take the conversation way to personally. Most of the time it seems parties in a controversial subject are able to get along well enough to put their points across. Leaving well enough alone appears difficult. Almost like a couple quarrelling over nothing yet, 

much hurt feelings as a result.

Some things are not worth it.

Live with it...

[Travis In Austin]

On 12/15/2021 at 7:09 AM, pcbiz said:

Thanks for the input. I assumed ALK's crossovers are more in line with modern Klipsch crossovers, and Dean G's crossovers are more in line with the originals on steroids. I really should get Dean G's crossover and compare it to my audio memory of the ALKs in my Heresy pair, or just get both.

Um, NO. Roy's latest networks (AL5, and AK6) were both from Paul's notebooks (which were given to Roy). You would have to ask @Edgar about the poles, etc., etc. He was smart enough to follow along with Roy as he was explaining what he did. I simply copied off of Edgar and got an A+.

[Travis In Austin]

5 minutes ago, billybob said:

Think most could care less about a crossover network.

Others whether serious or just owners like to experiment. 

Some take the conversation way to personally. Most of the time it seems parties in a controversial subject are able to get along well enough to put their points across. Leaving well enough alone appears difficult. Almost like a couple quarrelling over nothing yet, 

much hurt feelings as a result.

Some things are not worth it.

Live with it...

I wish I could have said it like that. Well said.

[henry4841]

1 minute ago, Travis In Austin said:

I wish I could have said it like that. Well said.

 

8 minutes ago, billybob said:

Think most could care less about a crossover network.

Others whether serious or just owners like to experiment. 

Some take the conversation way to personally. Most of the time it seems parties in a controversial subject are able to get along well enough to put their points across. Leaving well enough alone appears difficult. Almost like a couple quarrelling over nothing yet, 

much hurt feelings as a result.

Some things are not worth it.

Live with it...

I agree with that statement. But there is one person that will disagree about how important after market x-over are and will keep posting and posting and posting. 

[henry4841]

12 minutes ago, mboxler said:

Yep, a 15 ohm resistor is what is needed for attenuation. Something has to be missing. You did not read my previous post of how much attenuation that would be. Unrealistic amount. No way. 

[Edgar]

I'll just make a drive-by comment and say that there's more than one way to skin a cat. 

 

In a crossover network, as with any network, there are a number of parameters that can be optimized. Fully competent designers may disagree not only on what to optimize, but on how to optimize it. That doesn't make any of them right or wrong, it just means that they approach the problem differently.

[henry4841]

1 minute ago, Edgar said:

I'll just make a drive-by comment and say that there's more than one way to skin a cat. 

 

In a crossover network, as with any network, there are a number of parameters that can be optimized. Fully competent designers may disagree not only on what to optimize, but on how to optimize it. That doesn't make any of them right or wrong, it just means that they approach the problem differently.

I agree with that but engineers have an obligation to their company to design circuits that work for as cheap as they can. Simple with few parts mean saving money. One reason autotransformer are no longer used for attenuation if 2 resistors can do the job just as good if not better. I think actually better. 

[billybob]

17 minutes ago, henry4841 said:

 

I agree with that statement. But there is one person that will disagree about how important after market x-over are and will keep posting and posting and posting. 

At the risk of appearing to take sides, which I do not know enough to do, isn't the end goal basically the same if for instance 2 technicians see the answer, yet arrive at it by using different methods.

Of course, the better course may prevail over time.

Seems at times this discourse is tinged more with personalities rather than the subject matter.

Thanks!

[Edgar]

1 minute ago, henry4841 said:

I agree with that but engineers have an obligation to their company to design circuits that work for as cheap as they can. Simple with few parts mean saving money. One reason autotransformer are no longer used for attenuation if 2 resistors can do the job just as good if not better. I think actually better. 

 

I respectfully disagree with both points.

 

I am tasked by my employer to design the best (whatever) that I can within the cost target. If I am designing a premium product then it is understood that I will not make it as cheap as possible -- then it wouldn't be a premium product.

 

L-pads only work when the load impedance is constant. A loudspeaker load impedance is seldom anything near constant, unless compensated by Zobel or similar.

[Edgar]

2 minutes ago, billybob said:

At the risk of appearing to take sides, which I do not know enough to do, isn't the end goal basically the same if for instance 2 technicians see the answer, yet arrive at it by using different methods.

 

This assumes that there is only one "answer". That is only occasionally true. Hence thousands of different loudspeaker designs, all claiming to do the same thing: faithfully reproduce audio.

[Travis In Austin]

2 hours ago, henry4841 said:

We have drawn the attention of Travis with our back and forth and to me this is not worth it. 

Only the personal stuff draws my attention. I like what you post that is free from it. I have learned a lot from you, although there is much I don't understand. As someone earlier mentioned, most are not going care about the hyper-technical stuff. 

 

Lately, it seems, networks and their components have become a very, very contentious subject. Perhaps it has always been that way and I just never noticed? I don't care if their are opposing viewpoints, I do think there are ways to stick to your guns without going off the tracks. 

 

One thing I do know, after watching Roy explain this stuff, modern network design isn't something for the uninitiated. One change causes multiple other changes (impedance is just one example). Then you have to voice it across an entire line. 

[Travis In Austin]

4 minutes ago, Edgar said:

 

I respectfully disagree with both points.

 

I am tasked by my employer to design the best (whatever) that I can within the cost target. If I am designing a premium product then it is understood that I will not make it as cheap as possible -- then it wouldn't be a premium product.

 

L-pads only work when the load impedance is constant. A loudspeaker load impedance is seldom anything near constant, unless compensated by Zobel or similar.

Don't you also have to account for phase? As an additional factor to contend with?

 

"No sound in nature has constant phase" RDJ

 

So you have phase, slope, impedance as intertwined parameters? There are others as well are there not?

[henry4841]

The crossover network is the brains of a speaker system. Deviating from what the engineers designed is not for the novice. Very very few individuals has access to an anechoic chamber for testing or the equipment needed to do so properly. Most of the time best to leave well enough alone. Changing parts will change the sound but one may not like what they hear. Crap shoot actually. I did experiment with different ones a long time ago and it took months and months trying 30 or more designs. Some I like better then stock but in the end I just put my AA's back in my LaScala's. No fancy caps or inductors either. Went with what PWK liked best motor run caps as well. 

[Edgar]

1 minute ago, Travis In Austin said:

Don't you also have to account for phase? As an additional factor to contend with?

In my opinion, yes; phase is extremely important. Others feel that it can be ignored entirely. Who is correct? Well, there are plenty of good-sounding loudspeakers with crossovers that were designed without regard to phase.

 

Quote

So you have phase, slope, impedance as intertwined parameters? There are others as well are there not?

 

Oh, yes! For example, very few people even consider time domain response. I am in the camp that believes it to be vitally important.

[Travis In Austin]

28 minutes ago, henry4841 said:

 

I agree with that statement. But there is one person that will disagree about how important after market x-over are and will keep posting and posting and posting. 

I agree with you. There are many who disagree on a number of things. If doing just a straight update for example, there is this battle on whose update is better. 

 

"Imitation is the greatest form of flattery" was the ad campaign that they ran in response to the Speakerlab copies, they got one and put it in the chamber and it was compromised. 

 

If people are going to change drivers, horns, etc., then they are going to get their networks for those, etc. Just don't call it Klipsch. 

 

If you want the real deal, call JEM.

 

If you want the latest and greatest, than an AL5 is where you need to be.

[mboxler]

1 hour ago, henry4841 said:

Yep, a 15 ohm resistor is what is needed for attenuation. Something has to be missing. You did not read my previous post of how much attenuation that would be. Unrealistic amount. No way. 

 

If one assumes the impedance of the K55 is around 15 ohms, then I would say the AK-4 filter was designed for a 30 ohm load, and the voltage drop across the K55 would be around 6db.

 

If one were to design the same filter with a 15 ohm L-Pad, then you simply double all the capacitors and halve all the inductors to get a similar frequency curve.

 

I'd be happy to simulate the above, just to see if I'm close.  

 

Oh...I never said adding a series resistor would not decrease the current through the circuit.  I fully realize that, with a properly designed L-Pad, all other component values can remain unchanged.

 

Edit...should have said 6db

 

Mike

[OO1]

4 hours ago, Travis In Austin said:

 

 

"Imitation is the greatest form of flattery"

Copies of  Klipsch PWK  Crossover Designs  are called   "custom built crossovers  for Klipsch speakers".......

[henry4841]

42 minutes ago, mboxler said:

 

If one assumes the impedance of the K55 is around 15 ohms, then I would say the AK-4 filter was designed for a 30 ohm load, and the voltage drop across the K55 would be around 6db.

 

If one were to design the same filter with a 15 ohm L-Pad, then you simply double all the capacitors and halve all the inductors to get a similar frequency curve.

 

I'd be happy to simulate the above, just to see if I'm close.  

 

Oh...I never said adding a series resistor would not decrease the current through the circuit.  I fully realize that, with a properly designed L-Pad, all other component values can remain unchanged.

 

Edit...should have said 6db

 

Mike

Interesting and I believe you are correct. Never seen a crossover designed like that but what made me reconsider the design is the wattage of the 15 ohm resistor in the mids and the 5 ohm in the tweeter. Burning a lot of juice by their rating. Do not understand why they designed it the way they did but I am sure they had good reasons. Eat crow, not the first time though. 

[mboxler]

19 minutes ago, henry4841 said:

Do not understand why they designed it the way they did but I am sure they had good reasons.

 

My theory, it's all about real estate.  A 4mh inductor takes up maybe 20% more space compared to a 2mh.  It seems as though Klipsch likes 50uf capacitors max, which are almost as large as the inductors.  Without stacking you are doubling the capacitor space occupied when you double the capacitance.

 

Again...only a theory.