[TheoS53]

@skerry2006aj
 
this is the graph of H vs low gain
 
Red is L, black is H. (the reason H is lower than L on the graph is because I lowered the input volume to try and get them close to each other for comparison)
 

 
As for distortion, I'm having issues trying to use the X5 as a DAC, but here are some measurements of the E12, for what it's worth
 
E12 LG
 

E12 HG

 

[JaZZ]

  Thanks Theo
 
So it's essentially flat with no EQ, and rolls off at 30 Hz (steep) and 8-10kHz (slow) under EQ.
 
Given that there isn't a lot of audible sub-bass in most music below 30Hz, and the roll off is very slow (well under 0.5dB from 10-15kHz), and roll-off is going to be pretty much inaudible anyway (unless you're the type with golden ears who listens mostly to test tones 

 ) - then I see nothing to really worry about

 
But keep in mind that that's a rather unrealistic EQ setting. With more realistic scenarios you wouldn't get (such) a drop-off at the frequency extremes.

 

[Brooko]

Other way around Jazz
 
Theo was trying to follow the original unequalized frequency map after EQ had been applied.  So under EQ (and I guess it has something to do with filtering), the X5 has frequency drop off below 30Hz and above 8-10 kHz.
 
To compensate for the frequency drop he applied the EQ settings above 
 

 The settings for this eq was:

31 : 2 clicks below +6
62 - 8k : 3 clicks above +4
16k : all the way to the top

 
Without applying those settings the drop would be steeper (at least that is the way I understand it anyway)

 

[TheoS53]

  Other way around Jazz
 
Theo was trying to follow the original unequalized frequency map after EQ had been applied.  So under EQ (and I guess it has something to do with filtering), the X5 has frequency drop off below 30Hz and above 8-10 kHz.
 
To compensate for the frequency drop he applied the EQ settings above 
 
 
Without applying those settings the drop would be steeper (at least that is the way I understand it anyway)

absolutely right. Because we have no way of adjusting eq below 31hz or above 16kHz 

 

[Brooko]

  absolutely right. Because we have no way of adjusting eq below 31hz or above 16kHz 

 
And really speaking it won't matter anyway as below the 30 and above 16K is not really going to dramatically affect the audible spectrum.

 

[TheoS53]

   
And really speaking it won't matter anyway as below the 30 and above 16K is not really going to dramatically affect the audible spectrum.

Just to clarify...when going from the OFF eq, to an unaltered Custom, the FR is exactly the same but with a 6dB drop

 

[Lad27]

Yes, that how it works.

 

[Lad27]

  @skerry2006aj
 
this is the graph of H vs low gain
 
Red is L, black is H. (the reason H is lower than L on the graph is because I lowered the input volume to try and get them close to each other for comparison)
 
 

 
Do you remember, how much of the volume drop it was in numbers on the volume indicator? Just curious.

 

[nmatheis]

Some fellow head fi'ers were concerned that applying around +4dB to all EQS sliders would result in a lot of dips /spikes across the frequency range. Theo's FR graph helps answer that question very nicely.

Thanks again, Theo! Your measurements confirm what I'm hearing.

 

[TheoS53]

   
Do you remember, how much of the volume drop it was in numbers on the volume indicator? Just curious.

there is about 5.6dB difference between L and H, which translates to 11 volume steps

 

[Dobrescu George]

Thanks a lot for all the help and all the hard work! i really appreciate the resoults!

 

[JaZZ]

  Other way around Jazz
 
Theo was trying to follow the original unequalized frequency map after EQ had been applied.  So under EQ (and I guess it has something to do with filtering), the X5 has frequency drop off below 30Hz and above 8-10 kHz.
 
To compensate for the frequency drop he applied the EQ settings above 
 
Without applying those settings the drop would be steeper (at least that is the way I understand it anyway)

 
No, you're screwing it up. Here's Theo's initial statement:

  Gents,
 
I tested out the EQ to try and see what levels the sliders would have to be in order to match the volume of the OFF eq.......it's impossible.
 
Everything between 31 and 8kHz can be matched...but before 31 and after 8kHz is impossible to replicate

 
If you select the custom EQ or one of the preset EQs and set the sliders to flat (as a starting point), you get a flat curve identical to EQ off, but have to live with a 6 dB volume decrease. The drop-off at the extremes in Theo's example is the result of the outer bands being 31 Hz and 16 kHz instead of say 12 Hz and 36 kHz. This while trying to compensate for the 6 dB volume drop-off by increasing all frequency bands accordingly.
 
And while I'm at it: Theo, how is the resolution of your graphs? Are they smoothed in any way? They seem to consist of assembled straight lines of the length of one octave, with hinted corners at the joints. That's not what I would expect from a measuring graph.

 

[TheoS53]

   
No, you're screwing it up. Here's Theos initial statement:
 
If you select the custom EQ or one of the preset EQs and set the sliders to flat (as a starting point), you get a flat curve identical to EQ off, but have to live with a 6 dB volume decrease. The drop-off at the extremes in Theo's example is the result of the outer bands being 31 Hz and 16 kHz instead of say 12 Hz and 36 kHz. This while trying to compensate for the 6 dB volume drop-off by increasing all frequency bands accordingly.
 
And while I'm at it: Theo, how is the resolution of your graphs? Are they smoothed in any way? They seem to consist of assembled straight lines of the length of one octave, with hinted corners at the joints. That's not what I would expect from a measuring graph.

No smoothing...the reason you see lines like that is because it's not a linear scaled graph. 
 
Here's a new one on a linear scale
 

 

[Brooko]

OK - I understand you now Jazz - but if there are sliders at 8kHz and 16 kHz, and you apply the  approx +4 gain evenly through to 16 kHz, then wouldn't the drop off occur steeply at 16 kHz - not at the 8-10 that's indicated?  Just curious ......

 

[JaZZ]

...but if there are sliders at 8kHz and 16 kHz, and you apply the  approx +4 gain evenly through to 16 kHz, then wouldn't the drop off occur steeply at 16 kHz - not at the 8-10 that's indicated?

 
I'm just guessing: The ten EQ bands have no hard boundaries, but permeate and thus add to each other. So if you care for a flat response between as large as possible an aera, you necessarily end up with dropping-off extremes, since outside of them there are no frequency bands anymore which would add to the curve, compensating for the individual drop-offs outside of their center frequencies.