[John Buchanan]

Thought I'd bump this as I made a couple of changes.

 

[gilency]

Hi John: bumping your thread again. I have been able to reproduce the ED-1 frequency using my parametric equalizer. I wish I could compare an ED-1 with the Behringer settings. I wonder if anybody else has tried this.

 

[DolphinG]

Wow, such and old post and very helpful to know about ED series.
 
Well, if I can I wanna get one of these and listen to it with my Lambda Signature.

 

[soren_brix]

Very interesting post John, Thanks a lot for your contribution.
Inspired by your own listing of the fq rep. as a list of numbers in another thread, I put the numbers into Excel, and added the Lambda and Sigma fq rep. as well.
I was curious to see how the corrected Lambda compared to the Sigma, as the latter was design to include DF to some degree.
 

 
To some degree the ED'ed Lambda seems to simulate a moderate Sigma's fq response ...
 
My experience from trying to compensate the Sigma's was implementing a voicing that utilizes a simple shelf filter + a parametric filter for boos'ting the low bass. Compensating the roll off above 1kHz with 15dB to get flat response didn't sound right ... I ended up compensating approx +6dB in that region ...I guess that puts my correction somewhat a bit lower than the ED'ed Lambdas.
The Sigma seems to have some significant drops around 1,5-2,5kHz, again at 5-6kHz, or a boost of the 3kHz area that the ED corection seems to simulate. Is that where the added spatial experince stem from?
 
Makes me wonder if some ing. at Stax have balanced the fq response of Sigma with the Lambdas, balancing the amount of spatial experince with the tonal experience ...Anyways, I guess the ED box'es does a bit more than just making an Eq

 

[John Buchanan]

This is a reproduction of Stax' own frequency response chart of the Stax Lambda Professional, the earspeaker that the ED-1 was designed for. Feel like using that graph for the summing operation you used?
 
 

 

[soren_brix]

That is correct John! I have used graphs found at InnerFidelity as reference for plotting the Lambda and Sigma's, the ED-1 graph I found at Head-Fi.

 

[Jonathan66100]

Hi soren_brix : ) 
 
Believe that you can make a curve specially designed for the sigma with using rephase software ? http://sourceforge.net/projects/rephase/
 
Anyway Thank you Jhon and Soren for your previous post.