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ok heres the example:
threshold: 15db
ratio: 5:1
so does that mean every 5db the signal goes over 15 it allows 1db? so it would be 16db. right?

heres another:
threshold: 10db
ratio: 3:1
so every 3db the signal goes over 10 it allows 1db. so it would be 11db. right?

ok one more:
threshold: 15db
ratio: 3:1
so every 3db the signal goes over 15 it allows 1db. so it would 16db again. right?
thanx for ur time,
jal

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anonymous Wed, 11/07/2001 - 12:28

Hi Jal,
that's about right. It looks as follows:

Level In | Level out
example 1

13 | 13
14 | 14
15 | 15
20 | 16
25 | 17
30 | 18

example 2
8 | 8
9 | 9
10 | 10
13 | 11
16 | 12
19 | 13

example 3
13 | 13
14 | 14
15 | 15
18 | 16
21 | 17
24 | 18

PLEASE NOTE: Thresholds in reality are of course usually negative, i.e. the levels would rise like -14, -13, -12... etc.

Hope this clarifies,

Matthias

anonymous Wed, 11/07/2001 - 13:11

hey matthias,
it probably should clarify but it doesnt. im not sure which is ur threshold and what is ur ratio:
Level In Level out
example 1 13 13.... is it 1:13 ratio or what i dont get it.
Hi Jal,

Yeah, it's a bit difficult because it's hard to make a proper table with this interface.
OK, I was referring to your three examples, i.e. taking the threshold and ratio you were mentioning. And all I did was to draw up a table to show how the Out level relates to the increasing in level. you could draw a graph from it and would see how the compression curve flattens above the threshold.
But your thinking of the first post was right.

cheers

Matthias

BTW: I've edited my post - maybe it makes more sense now... ?

drumsound Wed, 11/07/2001 - 21:01

Originally posted by jal:
ok heres the example:
threshold: 15db
ratio: 5:1
so does that mean every 5db the signal goes over 15 it allows 1db? so it would be 16db. right?

heres another:
threshold: 10db
ratio: 3:1
so every 3db the signal goes over 10 it allows 1db. so it would be 11db. right?

ok one more:
threshold: 15db
ratio: 3:1
so every 3db the signal goes over 15 it allows 1db. so it would 16db again. right?
thanx for ur time,
jal

Jal,
By your definitions in your post I don't think you quite understand the relationship of Threshold and Ratio. The way it works is: if the input signal goes over the threshold, its level is reduced (compressed) by the ratio. Audio under the threshold will not be effected. I'm math--phobic so I won't try to give actual numbers, Matthias has done that for you.

anonymous Wed, 11/07/2001 - 21:08

no i did understand that part i was just trying to understand exactly what the ratio does, cause ive heard and read a couple different things. i couldve read them wrong.
but i just wanted to make sure and now i know.
thanx guys,
jal
anyways isnt it he ear thats always right in this game thats why i love recording soooo much.

Ang1970 Thu, 11/08/2001 - 01:08

Being negative, the dB number represents distance from the zero reference... in other words, when the signal is at -20, it is 20dB lower than 0dB. With that in mind, here is a new way of looking at the table.

Threshhold -15, Ratio 5:1
These settings mean that the compressor will pass 1dB for every 5dB above -15 that is fed into it.
INP=input level
OUT=output level
OVER=amount over threshhold
PASS=amount of signal passed over threshhold
REDUC=amount of reduction

[list]

  • INP | OUT | OVER | PASS | REDUC
  • -20 | -20.0 | 00.0 | 0.0 | -00.0
  • -17 | -17.0 | 00.0 | 0.0 | -00.0
  • -15 | -15.0 | 00.0 | 0.0 | -00.0
  • -12 | -14.4 | 03.0 | 0.6 | -02.6
  • -10 | -14.0 | 05.0 | 1.0 | -04.0
  • -07 | -13.4 | 08.0 | 1.6 | -05.4
  • -05 | -13.0 | 10.0 | 2.0 | -08.0
  • -02 | -12.4 | 13.0 | 2.6 | -10.4
  • -00 | -12.0 | 15.0 | 3.0 | -12.0
  • +01 | -11.8 | 16.0 | 3.2 | -12.8
  • +02 | -11.6 | 17.0 | 3.4 | -13.6
  • +03 | -11.4 | 18.0 | 3.6 | -14.4
  • +05 | -11.0 | 20.0 | 4.0 | -16.0
    class="xf-ul">When the signal is at -10, it is 5dB above the threshhold of -15. The compressor reduces the gain by 4dB, allowing the output level to be -14, or 1dB above the threshhold of -15.

    Hope that helps.

  • Ang1970 Thu, 11/08/2001 - 17:12

    Yes, I could have kept the table going into positive input values... I'll work on it in a bit... :)

    Threshhold +5, Ratio 5:1
    These settings mean that the compressor will pass 1dB for every 5dB above +5dB that is fed into it.
    INP=input level
    OUT=output level
    OVER=amount over threshhold
    PASS=amount of signal passed over threshhold
    REDUC=amount of reduction

    [list]

  • INP | OUT | OVER | PASS | REDUC
  • -20 | -20.0 | 00.0 | 0.0 | -00.0
  • -15 | -15.0 | 00.0 | 0.0 | -00.0
  • -10 | -10.0 | 00.0 | 0.0 | -00.0
  • -05 | -05.0 | 00.0 | 0.0 | -00.0
  • -00 | -00.0 | 00.0 | 0.0 | -00.0
  • +05 | +05.0 | 00.0 | 0.0 | -00.0
  • +06 | +05.2 | 01.0 | 0.2 | -00.8
  • +08 | +05.6 | 03.0 | 0.6 | -02.4
  • +10 | +06.0 | 05.0 | 1.0 | -04.0
  • +12 | +06.4 | 07.0 | 1.4 | -05.6
  • +15 | +07.0 | 10.0 | 2.0 | -08.0
  • +18 | +07.6 | 13.0 | 2.6 | -10.4
  • +22 | +08.4 | 17.0 | 3.4 | -13.6class="xf-ul">