Send Block vs. Y-split

[bpugs]

I have been trying for days to get a Send and its Return block to imitate a y-split. In this case I use a small cable to connect the send and return however there is always a tone loss when compared to simply using a y-split. I have determined it is not the cable through isolation testing, so I am now wondering what settings I could possibly set to make these functions interchangeable. Pictures below for reference, the one with send and return blocks is much more brittle, however all settings are effects and settings are identical (the volume block is bypassed and is acting as a place holder to preserve the parallel path).

[Schmalle]

Phase cancellation due to time delay caused by DA->AD conversion in the loop.

[bpugs]

On 7/25/2023 at 8:02 PM, Schmalle said:

Phase cancellation due to time delay caused by DA->AD conversion in the loop.

This appears to be it! Is there any potential solution to this issue?

 

I noticed that adding a return block in path 1 fixes it, but I am really trying to keep my other return block clear to add another instrument. So are there any other work arounds?

[Schmalle]

On 7/26/2023 at 3:09 PM, bpugs said:

This appears to be it! Is there any potential solution to this issue?

 

I noticed that adding a return block in path 1 fixes it, but I am really trying to keep my other return block clear to add another instrument. So are there any other work arounds?

I attached an IR file that adds a delay of 72 samples which should perfectly compensate for the loop's delay.

Load it in an IR block with level set to zero in the non-return-block path.

 

(right-click -> save audio as...)

[bpugs]

On 7/26/2023 at 10:28 AM, Schmalle said:

I attached an IR file that adds a delay of 72 samples which should perfectly compensate for the loop's delay.

Load it in an IR block with level set to zero in the non-return-block path.

 

(right-click -> save audio as...)

 

You're awesome, I'll try this out when I get home. Thank you so much!

[Schmalle]

On 7/26/2023 at 4:32 PM, bpugs said:

You're awesome, I'll try this out when I get home. Thank you so much!

Forgot to mention: I did that with the HXStomp - not shure if the Helix's loop introduces the exact same delay.

 

If not feel free to record one note in stereo with both channels and post it as an mp3-attachment so that I can identify the delay and build a custom IR. Peace of cake in Audacity. 

[bpugs]

On 7/26/2023 at 10:45 AM, Schmalle said:

Forgot to mention: I did that with the HXStomp - not shure if the Helix's loop introduces the exact same delay.

 

If not feel free to record one note in stereo with both channels and post it as an mp3-attachment so that I can identify the delay and build a custom IR. Peace of cake in Audacity. 

Hey, so I uploaded the IR and it didn't work perfectly. But I looked it up and it seems that the helix lt has a conversion delay of 1.8ms. So I created a file like yours with a single notch at 1.8ms and I am getting pretty great results! I tried to get as close as I can to 1.8ms in audacity but it's not perfect, but let me know if you can do any better. Thanks!

[Schmalle]

On 7/27/2023 at 3:13 PM, bpugs said:

Hey, so I uploaded the IR and it didn't work perfectly. But I looked it up and it seems that the helix lt has a conversion delay of 1.8ms. So I created a file like yours with a single notch at 1.8ms and I am getting pretty great results! I tried to get as close as I can to 1.8ms in audacity but it's not perfect, but let me know if you can do any better. Thanks!

Nice. The file looks right. You can do it on your own then.

Tips:

• Measure the delay exactly by recording and comparing both channels simultaneously and play a note.
• Measure whether your IR works perfectly the same way (with the IR on of course). 
• Tweak (add or delete samples of silence before the impulse) and repeat if needed.

 

And: There *might* be a change in delay depending on the complexity of the patch - I didn't check that.

[brue58ski]

This is all good info I never would have figured out if I had come across it. Thank You!!!

[Schmalle]

There apparently is another way to do this:

 

Take a legacy PingPong Delay with Feedback 0%, Spread 0%, Mix 100%, Level 0dB. It is the least DSP-expensive flat sounding delay.

Save and export the preset. Open with text editor, find the line ' "Time" : ' and input i.e. '0.0018,' for 1.8ms = 0.0018s. 

Save and import the preset file. Unless you touch the time parameter you now have the desired compensating delay.

 

Test if it really aligns both phases and -if needed- repeat the process with more fitting delay time.

 

It's a good idea to save the delay as favorite.