DC Coupled Analog In/Outs

[tomylee]

Hi,

Do any of the h8000 series units have dc coupled analog ports or any other possibility to control external analog gear with dc control signals?

that – would be very nice…

if not, is it easy to remove the capacitors or somehow mod the analog circuitry to allow it?

greets
tomylee 

[nickrose]

The outputs of the H8000 series are DC-coupled, the inputs are not.

But, needless to say, the use of the H8000 for dc control applications is somewhat unsupported …

[tomylee]

thx for the tipp, im trying it out anyway when I got my first semimodular synth…;)

[DaveFX]

For a DC control voltage input to the H8000 series, take another look at the documentation of the Foot Pedal Jacks 1 and 2 in the manual.  For each TRS jack (Tip-Ring-Sleeve), the Sleeve is ground (as you'd expect), and the Tip accepts an analog control voltage (0 to +5VDC, relative to the Sleeve).  So I bet you could input your control voltages using the Tip and Sleeve.  The H8000 calibration procedure should also work.

WARNING — You would need to make sure your control voltage would stay within 0 to +5VDC.  You would want to confirm this firsthand with a multimeter (not just reading documentation).  The multimeter would not need to be fancy or expensive — the most important thing would be to see your voltages firsthand.  Be aware that you would be applying your own voltage directly into the Eventide.  If this feels a little scary, that’s good — that scary feeling is just telling you to think this through.  Applying voltage out of range can fry the H8000.

Of course, the H8000 series also supplies +5VDC to the TRS Ring as a convenience.  This gives us the more typical way to apply a control voltage to the Tip — by using a potentiometer as a voltage divider between the Ring (source) and the and the Sleeve (ground).  This is also the SAFEST way to apply a control voltage to the Tip, because it is naturally limited to the range 0 to +5VDC defined by Ring and Sleeve.

With that in mind, if your application is a modular analog synth setup with dedicated hardware knobs for tweaking in real time, then you might consider making your own dedicated hardware knobs for the H8000.  Instead of using a footpedal, you can buy your own potentiometers (with linear taper, not logarithmic audio taper), and run cables back to the TRS footpedal jacks.  I control my H8000FW output Post D/A Gain this way.

[tomylee]

hi dave, thx for the precious tipps, I dont know why I dont use my footpedal anymore with the h8000 but I think it was because it was too laggy and maybe the footpedal input was not handled at audio rate, resp. modrate.

But I will check this again now, maybe I was doing something wrong back then, I guess last time I tried this was 2 years ago..

[tomylee]

jep, that was it…the extrenal control module has a lousy control signal output, rather than a mod rate output which is a purely unecessary limitation that prevents me from feeding external envelopes, lfos etc to the eventide.

To Eventide: Maybe you can give us a module that reads the control voltages at the pedal ins at audio or mod rate, along with the fixed mod filter in the next update

I dont know if you know about the importance of such a module, as it seriously would connect the h8000 to any modular system multiplying the power of digital and analog to an incredible extent…just immagine using analog lfos and envelopes on your tide, or let some module trigger the rlfo of the tide, which in exchange would control anything else in the modular system, the uses would be incredible, dont sleep over this development…

damn I would program that module for myself if I had the h8000 sdk… 🙁

give me good news!

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