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Stereo vs Mono Chains & DSP Load

Am I correct in assuming that stereo chains automatically convert all units to stereo which in turn doubles CPU load compared to mono chains? Also does spreading units across two chains help with CPU load even if I’m running the ER-301 as a single stereo out? Thanks in advance.

Welcome. I don’t think a stereo chain is necessarily going to double CPU. You can try it out if you like. Create a mono chain. Check CPU. Then hold down that channel button and an adjacent one, and it will convert it to stereo.

I’m not sure I understand the second part of your question but I think the answer is no. Most units take a fixed amount of CPU regardless of whether there’s any signal to them or where they’re located. Some of the granular units are an exception due to polyphony (but still doesn’t matter where they are in a chain).

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Got it thanks.

you can also be a little crafty with CPU management depending on what you’re up to:

If all your sources are mono but you want to add some stereo thickening, there’s no need to run them stereo. You can keep them mono on ie: Ch 1 and 2 or Globals and process them in stereo at the end:

Link ch 3/4 for your master stereo bus, add some channel mixers (which will have pans) and also add Delays and Verb here as they’ll be in stereo.

Then route your mono Ch 1,2, globals (or the out of any mono process) to the input of one or more stereo channel mixers to add that last bit of stereo ‘sweetening’.


Right on Neil, so in your example you’re advising to put the bulk of the patch on mono chains 1 & 2 and then have the ganged 3&4 (stereo) be responsible for a few low CPU stereo FX right? and then do all of signal routing internally via locals?

it really depends on what you want to accomplish - but if your source audio files are mono, it’s a waste of CPU running it in stereo along with all stereo units throughout - when you can apply that stereo sprinkling right at the end.