Lascala cabinet resonance

[the real Duke Spinner]

Damping Factor I'd an interesting chase Many of my Crown amplifiers I e. studio Reference have a damping Factor of 4000 or so

They can sound very dry.

[Schu]

That is why you only use ultra high damping on LF sections...

[OO1]

, the Crown Reference Studio Reference I or II have a Damping Factor: of   >20,000 from 10 Hz to 400 Hz.

[82 Cornwalls]

And yet it's just as meaningless as 4,000.

[OO1]

[Flevoman]

OK, I'm a bit confused now... 

So what is better, a high or a low damping factor? 

[OO1]

high  

[82 Cornwalls]

1 hour ago, Flevoman said:

OK, I'm a bit confused now... 

So what is better, a high or a low damping factor? 

 

Here is a summary that of course is slanted to their amplifiers, but it is fairly accurate.

https://benchmarkmedia.com/blogs/application_notes/audio-myth-damping-factor-isnt-much-of-a-factor

 

Here is a better summary

https://butleraudio.com/damping1.php

 

Floyd Toole basically says a damping factor of 20 is sufficient, the rest is up to the speaker.

 

[Islander]

On 12/22/2023 at 10:11 AM, mikebse2a3 said:

 

What is it about the shape that causes the 148Hz peak… ?

 

Looking at the Impedance Plots seem to indicate resonances of mechanical/acoustical nature.

 

Finite horn length and mouth size cause reflections in the horn due to impedance mismatching at the mouth/room interaction leading to what I understand to be standing waves and resonances in the horn.

 

@Chief bonehead maybe you can clarify what causes the 100Hz - 200Hz region of frequency/phase anomalies of the La Scala models.

 

miketn

 

What causes it?  Mike, that's beyond what I understand about horns.  I just know that the 148 Hz peak seems to be a characteristic of the La Scala bass horn, and is not due to resonance.

[Shakeydeal]

1 hour ago, Flevoman said:

OK, I'm a bit confused now... 

So what is better, a high or a low damping factor? 

I would rather have a great sounding amp than buy one just because of one measurement.

[82 Cornwalls]

@Islander

You made a comment about it in a thread from 2010.

 

"Since that bass peak is caused by the dimensions of the La Scala bass horn"

 

 

[Islander]

8 minutes ago, 83 LSIs said:

You made a comment about it in a thread from 2010.

 

"Since that bass peak is caused by the dimensions of the La Scala bass horn"

 

 

 

Yes, some topics seem to come around and go around.  Just don't say that you think that speaker cables bigger than 16 gauge might sound better, lol.

[billybob]

That is why got confused about which LS. The original had a  null or void caused by the AL crossover, which caused by measurement or ear, had people going to another network like the AA. Here we are talking an  LS-5 being haunted by recordings creating resonance like sound at approximately the same frequency. Or, maybe this is just a twilight zone moment.

IIRC... thanks.

[82 Cornwalls]

19 minutes ago, Islander said:

 

Yes, some topics seem to come around and go around.  Just don't say that you think that speaker cables bigger than 16 gauge might sound better, lol.

 

Happens on all forums.

 

I have Belden 9497 which is 16 gauge, but use it doubled up for @ 13 gauge.

In certain circles I don't mention the doubled up part so I don't have to hang my head in shame. 😁

[Islander]

17 minutes ago, billybob said:

That is why got confused about which LS. The original had a  null or void caused by the AL crossover, which caused by measurement or ear, had people going to another network like the AA. Here we are talking an  LS-5 being haunted by recordings creating resonance like sound at approximately the same frequency. Or, maybe this is just a twilight zone moment.

IIRC... thanks.

 

When it comes to that upper bass peak, it seems to be part of the horn's performance.  I can only suspect that PWK reasoned that in the compromises that are part of engineering any device, that "loss" was outweighed by a gain somewhere else.

 

Also, since the newer horns (up to and including the LS-5) still sound like that, it looks like Klipsch gets very few complaints about it, other than from the persnickety members of the Forum, who wish that the Heritage speakers were all perfect, just different flavours of perfect, with the bigger ones having bigger performance envelopes.

 

BTW, there is a slight difference in the newer (LS2 on) bass horns.  The new ones are about an inch longer, making the cabinets about an inch deeper.  This is noticeable in that the point of the Vee of the bass horn is recessed about an inch farther back than the Vee point of the original Scala.

[Islander]

8 minutes ago, 83 LSIs said:

 

Happens on all forums.

 

I have Belden 9497 which is 16 gauge, but use it doubled up for @ 13 gauge.

In certain circles I don't mention the doubled up part so I don't have to hang my head in shame. 😁

 

In my home, you won't find any wires smaller than 12 gauge, including the living room and bedroom systems.  When it comes to the bi-amped LS2s, the woofers get 8 gauge and the tweeters get 10 gauge, both in twisted pair configuration.  The 8s were bought before I got La Scalas, when their size made more difference.  However, they were still good, so I kept using them.  The 10s were a step down and were for the tweeters (which are rated at 50 watts max), so that seemed right.  The cables are 15 feet long, which may be a small factor.  However, the bigger cables cause minimum loss to the amplifiers' damping factor, as well as minimizing resistance/impedance.  And that's all I've got to say.

[Marvel]

I thought the peakiness was from the parallel sides (doghouse to outer side walls) for the 10 or 11 inches. Then John Albright said the Peavey FH-1 cabinets had it too, but I've not read that anywhere else.

 

Whatever, it never bothered me when I had La Scalas. I may end up with some again one day. If I do I will keep them, as I've missed them as soon as I let them go.

[billybob]

On 12/24/2023 at 3:20 PM, Islander said:

And that's all I've got to say

Yes, tell me more...

[OO1]

On 12/24/2023 at 3:01 PM, 83 LSIs said:

 

Happens on all forums.

 

 

[Woofers and Tweeters]

On 12/24/2023 at 1:04 PM, Flevoman said:

OK, I'm a bit confused now... 

So what is better, a high or a low damping factor? 

Higher, to a small amount. This subject has been debated since the Caveman days. From what I recall, there is too much to consider, such as the resistance of the cables, the construction of the speaker, the EMF produced by the speaker... and more, than to go by only the numbers.  It seems to hold to be true when looking at the DF of tube amps or the loved KH730 Twin (DF of 30).
I am not sure what curve it produces on a zy plane, but the gain on the x plane moves very little while adding a lot of y. I have read that anything past 40 is close to meaningless and is more for sales literature than for how well the system will sound. 

Knowing this, I still want a Sansui AU A907MR. Not because of the 0Hz to 300kHz, THD of only 0.003%, DF of 150, or that it weighs close to 75 lb, but because it sounds great.