Michael Thompson Micropitchshift on a DSP 7500

Discussion in 'The Rack Space' started by KennyM, Jan 13, 2018.

  1. swinginguitar

    swinginguitar Member

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    still working on it, @leonelh7

    thinking out loud here - the patch i've built lacks much in the movement department, being static detunes (aside from being able to modulate the pitch via lfo)...

    in my mind i'm picturing the chorus_delays algo set to have stereo mod delay in parallel to stereo chorus, all fed into this multishift+verb algo as sort of a caricature of the 80s rack thing...hmmm...lemme try that too...
     
  2. teofilrocks

    teofilrocks Supporting Member

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    I'm still looking at the algorithm block diagram for Multi-Shift (used in patch #519 MicroPitchShift) to see how it works.

    https://s3.amazonaws.com/com.eventi...nued+products/H3000_Series_Manual.pdf#page=95

    The first interesting thing about this algorithm is that it seems each side of the input gets split into parallel paths, one for pitch shift and one for delay, creating 4 outputs - each with it's own pan control. The next interesting thing is that each side gets two feedback paths, which can choose any of the 4 outputs as its source. Each output and each feedback path also has phase control.

    As I look over the pitch delay block diagrams from other processors (sorry, don't have a 7500) it's seems others have pitch and delay running in series. The PCM80 w/ PitchFX card, for example, has Quad and Dual algorithms, and they all run delay into pitch. The Axe FX III Plex Delay block does the same. And the Kemper Dual and Quad Chromatic Delays run pitch into delay. And they all do different things when it comes to feedback paths.

    Even though I don't have a 7500 or H3000, I'm still very interesting in understanding how this 519 patch works so I can try and emulate it in other boxes. I wonder if a quad delay that runs in series could be used. But voices 1 & 3 only utilize pitch, and voices 2 & 4 only utilize delay. And then do the best you can with what's available for feedback paths in your particular unit.

    I do wish I knew what the stock settings are for the whole 519 patch.
     
  3. swinginguitar

    swinginguitar Member

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    Keep it coming, brother.

    In the case of Eclipse, I dont think you'll get pitch (detune) AND delay in the same way configurations the big Eventides do - not quite that flexible

    correct me if i'm wrong

    but it looks like that H3000 structure is a little more self contained and designed to do this (IOW, you can fire up 2 blocks worth in Eclipse, but you'll never get that sophisticated with the feedback paths since you cant route back from block B to block A, etc)
     
  4. teofilrocks

    teofilrocks Supporting Member

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    Sometimes it helps to visualize, so here are clips of the block diagrams from various processors.

    H3000 : Multi-Shift
    [​IMG]

    Eclipse : Detune 4 Plex
    [​IMG]

    PCM80 PitchFX : Quad Hall
    [​IMG]

    Kemper : Quad Chromatic Delay
    [​IMG]

    Axe FX III : Plex Delay
    [​IMG]

    Perhaps these aren't all the best algorithms from their respective machines to capture the H3000 sound, but it's my best guess to start. The trick really seems to be in the feedback paths. But that's why I'd like to know what the stock #519 patch uses for feedback path settings. If it's on the simpler side, perhaps these other units can get by with something close.
     
  5. leonelh7

    leonelh7 Member

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    I been messing with the Lexicon, like @teofilrocks has mentioned and found some interesting sounds similar to the H3000. Need to find more time to polish the sound. In the Eclipse, it seems to struggle. Maybe I am doing something wrong. It’s also about the quality of the effects. I know the Kemper has some good sound and don’t have so much experience with the AXE FX III but I know the Lexicon can pull it out if you can sit down with it to do it.
     
  6. jaykay73

    jaykay73 Member

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    Are you sure #519 was built on Multi Shift? My H3500 manual says it's built on Layered Shift. I'm not near my machine right now so can't check - can someone check this please.

    JK
     
  7. teofilrocks

    teofilrocks Supporting Member

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    Page 179 of the H3000 manual says #519 uses Multi-Shift. Page 160 says #231 uses Layered Shift.
     
  8. jaykay73

    jaykay73 Member

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    Well that's weird. Page 158 of the H3500 manual says #519 uses Layered Shift. I'll check my machine next time it's on.

    JK
     
  9. teofilrocks

    teofilrocks Supporting Member

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    That’s interesting for sure.

    In this other thread post, it summarizes an HRI thread on the topic.

    https://www.thegearpage.net/board/i...thing-with-helix.1803061/page-2#post-23690297

    It’s suggested there that he might be using patch #531 Two Thickeners. The H3000 manual says that patch also uses Multi-Shift.

    A mystery that needs solving.
     
  10. jaykay73

    jaykay73 Member

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    From that post:

    - Michael is (likely) using preset 531, which is in the H3000 D/SE (and not in the original version)
    - Michael is also using preset 873 ("Rich Rhythm")

    1. How are we sure he is using #531 or #519? Which is it?
    2. How is he "also" using #873? Does he have two H3000s?

    JK
     
  11. swinginguitar

    swinginguitar Member

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    forget about Kemper FX - nothing notable in there mod/pitch wise (I only use the amps, ODs, and EQ blocks on kemper)

    I did some more work with the eclipse, and will hopefully post some patches at some point, for review and improvement from the community.

    In reality, they're not really the MT thing, but some nice heavily mod'd delays and detunes.

    Here's what I tried, after moving the multishift+verb to block B:

    1) put chorus_delays in block A for parallel chorus and delay feeding the detune and reverb structure. adds some nice movement and interaction; only downside is the delays are a little too strident (no hi cut in that algo)

    2) put delay_diffchorus in block A. Gets a nice smeared delay/chorus feeding the detune/verb. A bit more 'ambient'....but not much control over the chorus since it's wrapped up inside the diffusor.

    let's keep this discussion rolling - I"m learning!
     
  12. teofilrocks

    teofilrocks Supporting Member

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    I believe this is in the context of the YouTube video, where MT shows off a couple of his favorite patches to Tim and Pete.

    The video doesn’t show the patch #, but Italo says #519, so I’m good going by that. One this is for sure, whichever patch he’s using, it’s built off of Mutli-Shift, as opposed to Layered Shift. It’s confirmed in the video when they show a closeup of the H3000 screen while he’s setting the detune and delay. There’s a parameter on the screen that reads “l pdelay”. It stands for L Pitch Delay, as mentioned earlier in this thread. That parameter exists in the Multi-Shift algorithm, but not in Layered Shift.
     
  13. jaykay73

    jaykay73 Member

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    Thanks. When does he use Rich Rhythm? At the same time as #519 or independently?

    JK
     
  14. teofilrocks

    teofilrocks Supporting Member

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    He plays the first pitch delay patch, and then scrolls to another patch. Don’t know if it’s Rich Rhythm, he doesn’t call out the name IIRC. But you can see he’s only running one H3000.
     
  15. leonelh7

    leonelh7 Member

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    I think he says the patch is called Rich Rhythm. He uses an Echolution in the effects loop of the Mark to give him some Delay. Of course he is compressing the crap out of his tone.
     

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