Lexicon PCM70: Pan & Circular Delays + TC1210 Chorus

  • The diffusion in the Axe-Fx sounds quite different to the Lexicon. I've confirmed that the diffusion parameter in the PCM70 is not a mix control, but a time control. I measured the length of the diffusion on PCM70s Circular Delays preset, and then matched the length in the Axe-Fx. Finally, I tweaked it slightly by ear to find a value that was less metallic and more like the fluffy diffusion in the PCM70. The Axe-Fx diffusion is much harder sounding, and also has this kind of flanger-esque quality that changes the perceived pitch as the repeats goes on (think a ball rolling in a metal tube). I did my best with this. Want a more accurate diffusion? Stand on Cliffs lawn and yell at him! ;)
Vehemently disagree with this. Dug my PCM70 out of the closet and compared the diffusion to the Axe-Fx III. The Axe-Fx III is vastly superior. The PCM70 sounds metallic and comb-filtered. The Axe-Fx III sounds like a little reverb is added to each delay. You can stand on my lawn and yell all you want but I'm not changing this.
 
Vehemently disagree with this. Dug my PCM70 out of the closet and compared the diffusion to the Axe-Fx III. The Axe-Fx III is vastly superior. The PCM70 sounds metallic and comb-filtered. The Axe-Fx III sounds like a little reverb is added to each delay. You can stand on my lawn and yell all you want but I'm not changing this.
I don't know if you know, but the Axe Fx is the second part of the Circular Delays clip. I wouldn't describe the PCM70 as metallic or comb-filtered. That's how I would describe the Axe-Fx. Not meaning to argue, but I think the PCM70 sounds much better.

The funny thing is, if I change the diffusion time during the trailing repeats, the Axe sounds way more like the PCM70 all of a sudden. Even small changes bring out this behaviour.
 
I don't know if you know, but the Axe Fx is the second part of the Circular Delays clip. I wouldn't describe the PCM70 as metallic or comb-filtered. That's how I would describe the Axe-Fx. Not meaning to argue, but I think the PCM70 sounds much better.

The funny thing is, if I change the diffusion time during the trailing repeats, the Axe sounds way more like the PCM70 all of a sudden. Even small changes bring out this behaviour.
You're entitled to your opinion. I disagree. I'm not using an impulse to compare them, I'm putting audio through them and the Axe-Fx III sounds 100 times better. In my opinion.
 
I don't know if you know, but the Axe Fx is the second part of the Circular Delays clip. I wouldn't describe the PCM70 as metallic or comb-filtered. That's how I would describe the Axe-Fx. Not meaning to argue, but I think the PCM70 sounds much better.

The funny thing is, if I change the diffusion time during the trailing repeats, the Axe sounds way more like the PCM70 all of a sudden. Even small changes bring out this behaviour.
Not sure since it's just impulses... but to me the Axe-Fx's diffusion sounds like diffuse little reverbs while the PCM70's diffusion sounds like some low density simple stuff, and sounds crunchy not "fluffy."
 
Not sure since it's just impulses... but to me the Axe-Fx's diffusion sounds like diffuse little reverbs while the PCM70's diffusion sounds like some low density simple stuff, and sounds crunchy not "fluffy."
Agreed. I designed the Axe-Fx diffusers to sound like little reverbs. I like a little, 10-20%, which makes the echoes slowly turn into a wash. To me the PCM70 goes "brzzzzpppp" on the attack which I don't find pleasant at all.

I've experimented with diffusers for years. I hate all the examples in the literature (i.e. Schroeder allpass sections). I've implemented quite a few out of the papers and they all sound like crap IMO. I tried the allpass cascade in the JCRev algorithm again today and, yup, still sounds as bad as I remember.
 
Ok, update time!

The settings are now accurate to within 0.05 dB (used to be 0.10 dB).
Tweaked the diffusion a tiny bit.
On the PCM70, the diffusion causes the actual delay times to drift. I figured out a way to capture this.
 
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These sound great!!

Do you have any suggestions on how to retain the delay relationships relative to each other whilst taking advantage of the tap tempo feature?
 
These sound great!!

Do you have any suggestions on how to retain the delay relationships relative to each other whilst taking advantage of the tap tempo feature?
Well, the PCM70 couldn't do tap tempo. But, if you want to, look at my old Lukather X88R preset. I think the blocks were tap tempo compatible in it.

Copy those tempo numbers into these new blocks. Just remember to remove the feedback from feedback 4 in the Circular Delays block, and enter it into feedback 1 instead.

That "voice 4" is only there to capture the drifting of the times, which won't work with tap tempo. Don't worry to much about it. The accumulative difference will only be like 50 ms on the 6th round of repeats, which is over 5 seconds after the initial hit (assuming stock delay times).
 
Updated the blocks to take advantage of the new EQ section added in FW 14.01. The repeats now have a much more accurate frequency response in the high end roll off.
OP says lasted edited August 19, did you forget to upload the updated blocks?
 
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