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What is the crossover frequence for bass in AL-3


SpeedLimit

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10 minutes ago, SpeedLimit said:

ok ..

 

i first have put a 4,7 µF parallel to the 14µF. It is a little bit more than you said to me .. 14 + 4,7 = 18,7. I could put 3,3 µF to adjust

just making that, the meddle seem to be a little better but not enough level.

 

now i will try to change the resistors 15 ohms and 6,8 ohms .. if you think it will give me more level in the meddles

 

Ok it's Super :)

 

 

Attention !  µF et resistors are linked in this study, so if you listen to 18µF without 15 and 6.8ohm it will be slightly different than the simulation: everything is linked

 

18.7 and 3.3µF it's OK fort the test we will fine tune afterwards

 

9 minutes ago, SpeedLimit said:

and i do not want a high level tweeter .. not more than the meddles

OK >> we will fine tune afterwards. And then if we go back a little PD5VH we could perhaps leave it like that. Each change will influence the other, so let's take it slow

 

8 minutes ago, SpeedLimit said:

the atlas sound has a impedance of something like 13 ohms at the cutoff frequence

OK ! Yes I see >>> we will fine tune afterwards

 

 

>>>> If you want I can simulate the change of 18.7 and 3.3µF capacitors but without changing the resistors of the Lpad: this way you can visualize where you are.

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Here is the curve with the change of capacitors 18.7 and 3.3 µF: this is why the resistors must also be changed

 

9xla.jpg

 

 

 

 

To have fun and since it is Sunday and you cannot buy resistors: you can exchange the one you have on your filter: for example

 

ts0b.jpg

 

x8o1.jpg

 

😎

 

 

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i now have changed the 4,7 µF in parallel to the 14µF with a 3,3µF.

 

the resistor 15 ohms and 6,8 ohms for the meddle work not better than the 6,8 and the 10 ohms. The meedles was too low.

 

Now i will try to work on the tweeter .. i have a lpad (monacor pad) 8 ohms that i could use to make tests

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Super  😁

 

and the sound is better ?

 

And 10 series and 10 // you tried.

 

 

You will quickly think of letting your ear get used to it 😋

 

 

Edit A question to which you did not answer, please: are you in mono-amplification or in multi-amplification with volume control on each amp?

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1 hour ago, SpeedLimit said:

i stop making tests today ... my ears are bleeding !!

 

you have 3  options ----MINI DSP -------XILICA-------EV DX38  - to dial in the correct frequencies-

--networks alike the AL-3   are layouts of a set of configurations  -each change modifies the entire network ,  for an AL-3 - either you use it as is , or avoid it -

- I would  think the AA or A network /T-2A type  / 1-2-3-4  + or - 3db taps on both mids/tweeter , would be the simpler  solution  -

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3 hours ago, RandyH000 said:

 

you have 3  options ----MINI DSP -------XILICA-------EV DX38  - to dial in the correct frequencies-

--networks alike the AL-3   are layouts of a set of configurations  -each change modifies the entire network ,  for an AL-3 - either you use it as is , or avoid it -

- I would  think the AA or A network /T-2A type  / 1-2-3-4  + or - 3db taps on both mids/tweeter , would be the simpler  solution  -

 

He doesn't have an autoformer for his crossovers.

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11 hours ago, mustang_flht said:

I will answer here on the connection frequencies and on the reductions in db and the new impedences seen by the network

 

On PD5VH with 18µF (I remind you that to make 18µF, it suffices to add in // 4µF to the existing 14µF) and 15 in series and 6.8ohm in //

- connection frequency at -6db with 4mH and 136µF = ~ 330Hz
- reduction of 12.4db and impedence of 19.8ohm seen by the network for theoretical 16ohm.


On DE10 with 3µF and 2.2 in series and 6.8ohm in //

- connection frequency at -6db with PD5VH = ~ 4000Hz
- reduction of 4.1db and impedence of 5.9ohm seen by the network for theoretical 8ohm.

 

 

Be careful, this remains theoretical, there may be variations linked to the actual impedance curves (I could discuss more in detail later) and also linked to the response curves of the speakers.

 

That's why SpeedLimit needs to tell me what he likes and what bothers him, and then we'll adjust. Already the strong reduction in PD5VH risks disrupting his listening at the start, he will have to listen calmly, let his ear and his brain get used to it and tell me if he wants us to go back up. little or not the level of the PD5VH.

 

Ditto, same approach for the tweeter

 

OKAY ?

Regarding the 330 Hz: I forgot to specify that this setting is a plan B, because SpeedLimit lives on Reunion Island and he does not have easy access to component vendors. So the bias is to do the tests with what he has at hand and to preserve its 136µF and then to refine and make a connection to 450Hz K33 / K400-PD5VH for the final network.

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14 minutes ago, mustang_flht said:

So the bias is to do the tests with what he has at hand and to preserve its 136µF and then to refine and make a connection to 450Hz K33 / K400-PD5VH for the final network.

 

That should work fine. You should only need about a 6db cut on the midrange driver. Otherwise, the mids might seem too scooped out.

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17 hours ago, mustang_flht said:

Regarding the 330 Hz: I forgot to specify that this setting is a plan B, because SpeedLimit lives on Reunion Island and he does not have easy access to component vendors. So the bias is to do the tests with what he has at hand and to preserve its 136µF and then to refine and make a connection to 450Hz K33 / K400-PD5VH for the final network.

 

I have 50µF oil capacitors .. and 27 µF mundorf MKP ones ..

so i could make 77 µF ...

 

I have tried without the 136 µF .. so it make a 6 dB crossover with only the 4 mH inductance .. on 4 ohms, i don't have calculate what cutoff it makes

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Hi,

77µF will be perfect, in this case you can iron your PD5VH with the 14µF.

you can try this filter and tell us if the sound is good.

 

First, test with your 4mH coil, if you find that there is a hole around 300 / 400Hz, you can try a 3 or 2.7mH.

 

Based on your remarks yesterday, I also rectified the resistors of PD5VH and DE10 and the capacitor from DE10 to 3.9 or 4µF

 

Tell us if the sound is OK and if the db levels of each speaker are good

 

hz4b.jpg

 

ktn9.png

 

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mustang_flht

 

do you think i will have more meddles by changing the resistors 15 ohms - 6,8 ohms  to 10 ohms and 12 ohms ?

 

as i think to know :

 

eminence kappa 15c is around 99 dB sensitivity and with the bass bin probably something like 102 dB

pd-5vh is given to have 110 dB sensitivity

b&c de10-8 ohms something near 107 dB

 

at 450-500 Hz / 4000 Hz the pd-5vh has approx 13,2 ohms ,

at 4000Hz , DE10 has about 6,2 ohms as good as i can detect on the diagram af this driver

 

how do you calculate the attenuation ?

 

i would say - no attenuation for the woofer, 6 or 7 dB for the atlas and 3 or 4 dB for the de10 .. am i right ?

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5 hours ago, SpeedLimit said:

mustang_flht

 

do you think i will have more meddles by changing the resistors 15 ohms - 6,8 ohms  to 10 ohms and 12 ohms ?

 

as i think to know :

 

eminence kappa 15c is around 99 dB sensitivity and with the bass bin probably something like 102 dB

pd-5vh is given to have 110 dB sensitivity

b&c de10-8 ohms something near 107 dB

 

at 450-500 Hz / 4000 Hz the pd-5vh has approx 13,2 ohms ,

at 4000Hz , DE10 has about 6,2 ohms as good as i can detect on the diagram af this driver

 

how do you calculate the attenuation ?

 

i would say - no attenuation for the woofer, 6 or 7 dB for the atlas and 3 or 4 dB for the de10 .. am i right ?

 

102db, This is the first calculation I did yesterday, but you told me the Pd5VH was too low. Maybe I had dropped too much towards 100/101 and not really 102db. so let's simulate at 105db and if it's too loud it's because the truth is in the middle.

 

At a distance it's more complicated, let's now do 105 db, let your ears get used to it and tell me if we lower it later. In fact as we do not measure, the good setting will perhaps be at 103 or 104db theoretical electric, to make a real suitable acoustics.

 

Yes, I simulated the cutoff around 450Hz with PD5VH and 13ohm on the software.

 

For attenuation, I am using Virtuix software, as it combines impedance seen by the filter and component values. If we start from the calculation of the LPad to have for example 16ohm theoretical, you will need components. here I try to start from the components you have at home and I play on the impedance with a virtually false LPad.

 

With a LPad calculator like http://www.mh-audio.nl/Calculators/att.html

 

- For example with 10ohm in series and 12 ohm in //: we find for a PD5VH impedance of 13ohm, an attenuation of 8.3db and an impedance seen by the filter of 16ohm.

 

- and for DE10, if we take 8ohm of theoretical impedance of the HP, with 1.2ohm in series and 12 // on at 1.94db reduction for an impedance seen by the filter of 6ohm.

 

But since there are so many other parameters: real hp curve, impedance curve, overvoltage, filter slope, ... and since we do not measure what we are doing (which is not good ) that it is better in our case to start from an electrical simulation on the Virtuix software and then to adjust to the listening >>> your opinion

 

The most logical for me is: I simulate on the software, you tell me if it's ok, whether to lower or raise the hp PD5VH and DE10, if the connections are in your ear or if it is necessary to modify: and little by little I adjust the software and you tell me if it's better or worse.

 

Give me your listening impressions, it's important to me.

 

OK for you?

 

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