Finished My "Cornscala" Project

[TubesGlo]

6 hours ago, mopardave said:

Ok, what is the spl of your woofer?  Just curious to how many db your running the mid above the woofer.  Our combos are a bit different, but I’m just curious to your final setting.

Not sure about that, I haven't changed anything there. It just goes through the choke for low pass. This pic is how they were shipped and I followed Crites instruction recently to move the lead on tap 1 over to tap 2 while joining the terminals under the shrink wrap that connect the top capacitor to tap 5. I was asking for lower output from the squawker and Mike said this adjustment would put it at -12db vs -9db as in the picture.

That 3db attenuation brought everything in to balance for me, I like it much better. 

[mopardave]

28 minutes ago, TubesGlo said:

Not sure about that, I haven't changed anything there. It just goes through the choke for low pass. This pic is how they were shipped and I followed Crites instruction recently to move the lead on tap 1 over to tap 2 while joining the terminals under the shrink wrap that connect the top capacitor to tap 5. I was asking for lower output from the squawker and Mike said this adjustment would put it at -12db vs -9db as in the picture.

That 3db attenuation brought everything in to balance for me, I like it much better. 

Ok, I just looked it up. Your Crites 1526 spec is 97db spl, so with 12db of attenuation your running the mid 1 dB above your 110db spl mid driver.  The drivers are playing close to the same output.   Maybe I should try that setting on mine just to see.    Our mid horns are different and mine being open is very laid back, I actually think my mid could be bumped just a notch higher output. I’m now at 4db above my woofer output.I will have to try both ways again now that the speakers are in a much bigger room.

[Deang]

The picture shows Tap 1. 

 

Tap 1 is -12

Tap 2 is -9

 

When you moved it to Tap 2, you made the midrange 3dB hotter. 
 

Didn’t we just this (page 2).

[TubesGlo]

1 hour ago, Deang said:

The picture shows Tap 1. 

 

Tap 1 is -12

Tap 2 is -9

 

When you moved it to Tap 2, you made the midrange 3dB hotter. 
 

Didn’t we just this (page 2).

Dean, I don't build crossovers but I understand you are are an authority on the subject. I only quoted what the builder of these particular crossovers stated to me verbatim in his email. I suppose he could be mistaken or I'm mistaking the definition of attenuation.

 

"If I wanted to cut back the mid horn output just a bit, is there a simple tweak I could make on the network? I listen primarily to Jazz with sax and trumpet that comes through a little hot even at moderate levels."

 

 

"Jim, 

 

This mod simply changed the midrange attenuation from 9dB to 12dB. We originally intended them to be set at 12dB, but due to what people wanted we changed it to 9dB.

 

With this change the speaker will be more “correct”, we definitely prefer it that way.

 

Now you actually have the speaker the way we designed it.

 

Thanks, "

 

 

 

 

 

 

 

 

[Deang]

On 12/13/2021 at 10:03 PM, mopardave said:

The HM4750 has a slot, the HL4750 does not. The HM is still a 400hz horn.

 

Is the HM4750 the same as the M2380 or different? 

[Deang]

To attenuate means "to turn down". So, if you thought the midrange was "too loud', you would have wanted to go from Tap 2 to Tap 1.

 

I owe Michael a phone call anyways and I'll get some clarification on this. I do know what Bob thought, because he was aware of all of the complaints about the midrange being too forward. They definitely used to send them out on Tap 2 (-9dB).

[TubesGlo]

24 minutes ago, Deang said:

To attenuate means "to turn down". So, if you thought the midrange was "too loud', you would have wanted to go from Tap 2 to Tap 1.

 

I owe Michael a phone call anyways and I'll get some clarification on this. I do know what Bob thought, because he was aware of all of the complaints about the midrange being too forward. They definitely used to send them out on Tap 2 (-9dB).

Yes that's always been my understanding hence my request to decrease (attenuate) the midrange. He was aware that they were shipped with mid connected to tap 1 and knowing I wanted to tame it explained with a photo how to achieve it by moving the lead to tap 2 and connecting the 2nd 2.5uf cap leads attached to tap 5 that were shipped disconnected under heat shrink tube. This as stated was to drop (attenuate) the mid output by 3db down from -9 to -12. I have no way to measure this other than listening with my ears which tell me the mid is less forward and the drivers appear more balanced. I don't know the numbers, the right or wrong of it. I just did as instructed to achieve my goal and it worked. Clarification would be nice though I suppose.

[mopardave]

1 hour ago, Deang said:

 

Is the HM4750 the same as the M2380 or different? 

Their both 90x40 elephant butt cheek design, but the M2380's are a 500hz horn.    HM4750 is 400hz.  Both look the same to me.

[Marvel]

1 hour ago, Deang said:

 

Is the HM4750 the same as the M2380 or different? 

Different...

 

Here's pics of my hm4750 horns

 

[mopardave]

7 minutes ago, Marvel said:

Different...

 

Here's pics of my hm4750 horns

 

 

OH yeah, A lot different. Thanks for the great pics.   I may be trying a different horn in my CS.  I really miss the in your face mids that the old 600 horns had.

[mopardave]

10 minutes ago, Marvel said:

Different...

 

Here's pics of my hm4750 horns

 

 

Do you have any good pics of the M2380 horn?

[TubesGlo]

22 minutes ago, mopardave said:

Do you have any good pics of the M2380 horn?

Not the best pic I realize.

 

[Deang]

Is the 2380 like the HM4570 or the HL4570?

 

I’ve got 9 spec sheets up. JBL/Selenium doesn’t make it easy on you. All horns tested on different drivers, and those drivers on different horns.

 

No substitute for a microphone and a controlled environment. 

[mopardave]

1 hour ago, Deang said:

Is the 2380 like the HM4570 or the HL4570?

 

I’ve got 9 spec sheets up. JBL/Selenium doesn’t make it easy on you. All horns tested on different drivers, and those drivers on different horns.

 

No substitute for a microphone and a controlled environment. 

I agree.

[Deang]

@TubesGlo Okay, Michael says 12dB down is the correct setting (Tap 1). That would be for the D405 on the M2380. The Tap 2 setting is provided for those who prefer the midrange a bit more forward. He says it's possible he may have misunderstood your original email.

[mopardave]

1 hour ago, TubesGlo said:

Not the best pic I realize.

 

Ok, I’ll see if I can find one today.  I really like the looks of your CS.  Everything centered on the motorboard and the stain. Very nice. Mine started out as vertical CW home built. After 20 years I wanted something different.   That’s why my components might look kind of odd with their placement.   I’m now thinking seriously about trying a butt cheeks style mid horn just to see.

[mopardave]

6 minutes ago, Deang said:

@TubesGlo Okay, Michael says 12dB down is the correct setting (Tap 1). That would be for the D405 on the M2380. The Tap 2 setting is provided for those who prefer the midrange a bit more forward. He says it's possible he may have misunderstood your original email.

I checked the specs on my BC DE85 and says 108db spl not 107db like I read somewhere else, so I’m at 101db on my mid giving me 5db above the woofer spl.  That is very close to the same as TubesGlo . I like how I can hear everything in the recordings, very articulate, but missing something. In your face vocals and mid bass punch seems to be missing with this open horn.    I also noticed in the BC specs that this driver goes down to 500hz, the cross over and horn are capable of 400hz.  Do you think that could be an issue?

[Deang]

You have different horns. A horn will change the stated sensitivity of the driver. Look at the difference in the Directivity Index on these horns. So, your numbers won’t necessarily align with his.

 

Aren’t you using an ALK? So, 12dB/octave on the midrange, which definitely sounds different than 6dB/octave. 

 

 

[mopardave]

35 minutes ago, Deang said:

You have different horns. A horn will change the stated sensitivity of the driver. Look at the difference in the Directivity Index on these horns. So, your numbers won’t necessarily align with his.

 

Aren’t you using an ALK? So, 12dB/octave on the midrange, which definitely sounds different than 6dB/octave. 

 

 

I’m using your ALK universal.    So would it be an issue to try a different mid horn with my current components?

[mopardave]

40 minutes ago, Deang said:

You have different horns. A horn will change the stated sensitivity of the driver. Look at the difference in the Directivity Index on these horns. So, your numbers won’t necessarily align with his.

 

Aren’t you using an ALK? So, 12dB/octave on the midrange, which definitely sounds different than 6dB/octave. 

 

 

Ok, I’m think I understand you now. A slotted horn has more air pressure or resistance causing more electrical resistance(ohm) in the driver?