If sending recorded guitar (or other instrument) out from a DAW and into Sparks or Ribbons would you recommend a reamp box before the pedal?
I use pedals as send effects from/to my DAW/interface all the time, but have never tried a reamp. Just wondering what your thoughts are on it.
@joefox If you really what to recreate the sound of your guitar passing trough let’s say a happy face fuzz, a wah, then and good tube amp or a good amp simulator using a ramp box is the way to go, By the way before all the ramp boxes a passive direct box reversed was used with fairly good results. But now there are so many pedals that work really good with line level inputs. So yes, distortion, whas, and amps are sensitive to the impedance and level; time fx not that much. But that doesn’t mean that some distortion pedals sound incredible at line levels.
Ribbons and Sparks are really good with line level
I can see that @jaakjensen is typing a long reply hahahahaha I’m sure he is going to give you a much better and much more accurate explanation than mine hahahahaha 
hahaha
In general, if you’re sending guitar tracks from an audio interface to a pedal chain and amp, and you want the end result to sound like you played through an amp from the start, I recommend using a reamp box.
For example, if you recorded some DI’d guitar tracks while on the road, when you return to the studio, you may want to reamp those takes. A reamp box will mimic the impedance of the pickup and provide the correct output level to the pedal chain, which is particularly important for fuzz pedals. Fuzz pedal input /output impedances don’t play nice with audio interface input / output impedances.
If you’re processing drums, mixes, or other instruments with a pedal chain and you’re not using a fuzz pedal at the beginning or end, you likely don’t need to worry too much. Both Sparks and Ribbons have high impedance inputs and low impedance outputs, allowing you to plug them directly into the line inputs and outputs of your audio interface without needing a reamp box. You may need to adjust the level you’re sending to the pedal and boost it using a preamp or add gain in your DAW afterward, but this approach is perfectly fine. I would say the same for many other modern pedals.
During development, both my Sparks and Ribbons are primarily connected to my MOTU M4 line inputs and outputs, and I switch to the amp for final testing and tweaking of settings.
Appreciate the responses @jaakjensen and @Cornelius!
I figured as much. For pedal send fx I’m primarily only using pedals I’m pretty sure are line level ready.
Most modern/digital pedals accept line levels fine. For some, you may need to configure a setting, such as in Meris’ pedals. There are some exceptions that don’t work well. I have all my instruments go into my mixer, and then I send them to the pedalboard through an aux ouput which is line level. Most of my pedals work fine, except for the EHX Platform compressor (which I plan to replace soon) and the OBNE Dark Light (likes to clip like crazy, but I’m running it on a channel in my matrix mixer, so I can lower the input to it anyway). I have to lower the aux out level, but other than that, it’s working fine. I’m still thinking on getting a reamp box to see if it’s helpful.