Quad Cortex Captures lower gain and lack of dynamic response

I haven’t done that many captures yet, but have some observations on how to use the instrument and capture input 1 levels.

For pedals, you typically set the gain, tone and volume of the pedal in the context of a signal chain, getting it to do what you want it to do in terms of saturation, volume boost/cut (who ever cuts?) and tone. So when capturing the pedal, you likely want to keep the instrument and capture levels at 0dB so the resulting capture block behaves the same way as the real pedal did in the same signal chain. The capture will have the same gain/saturation and volume with the capture block parameters set at 0dB. Then you can tweak from there.

But capturing amps is different, they need to be set to have the right amount of headroom, and avoid digital clipping. I did a little testing, and found that QC clean amp models (like the Twin) have a default level of around -12dB and clip at around -6dB on the output when you turn them all the way up. That leaves 6dB of headroom on the output to avoid engaging the output limiters. A guitar with single coil pickups at input 1 (or return 1), is around -18dB or so. So to have your amp+cab capture normalized to be similar to a QC amp models, you’d might want a clean capture in level to be around -12dB and a distorted capture to be around -6dB. In most cases, you’d leave the instrument level at 0dB so that the capture block produces the same saturation as the amp.

In summary:

When capturing pedals:

  1. Set the pedal gain, tone and volume the way you want it in the signal chain
  2. Move the pedal into the capture loop
  3. Set instrument level to 0dB
  4. Set capture in level to 0dB
  5. Capture - the gain, and volume of the capture block will match the original pedal in the signal chain

When capturing amps:

  1. Put the amp+cab+mic into the capture loop
  2. Set the the gain, tone and volume on the amp way you want it
  3. Position the mic on the cabinet to get the tone you want
  4. Set instrument level to 0dB so the amp gain staging will be the same in the capture
  5. Set capture in level to get the level meter to show -12dB for a clean amp and -6dB for a distorted amp
  6. Capture - the gain/saturation, and volume of the capture block will match the original amp, and will have levels and headroom similar to the QC amps.
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My direct captures (using a WAZA Tube Amp Expander as DI/Load box) are pretty disappointing.

Missing gain, dynamic response and clarity.

Obviously my IRs are disabled on the WAZA.

I’ll try again tonight, following some of the advices mentioned here : such as increasing the input to the point where it clips.

UPDATE : I captured my amp where it was just on the border of triggering an error during the sanity check. The result was much more convincing : more alive, more dynamic, more gain.

The issue I had, is I got some kind of oscillating sound in the lows, primarily noticeable when palm muting power chords. Will lower the input and capture again.

I think it’s really a matter of finding the correct level and we cannot rely on the auto level.

I’ve had stellar results with captures. That being said, I will often tweak settings 4 or 5 times, making separate captures each time, then keeping whatever sounds the best. I have yet to use the AUTO SET and just pay attention to the meters. I have noticed a slight gain reduction in the captures, so I push it a little more in the amp.

I’m so impressed with the captures that I listed my OX on Reverb and put my ENGL amp on Craig’s List. :slight_smile:

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I have exactly the same problem. When I try to make a capture of H&K Tubeman DI, I always get noticeably less gain. Overall tone is similar, but slightly scooped. I tried different settings INSTR LEVEL and IN 1LEVEL, but I always get about 5 db less gain in a capture.

Has this been resolved?
I have this issue capturing treble boosters…
Thanks

No, it hasn’t been fixed yet. I am adding gain on my device before making a capture to fix this issue. David Maxim Micic told about this in this video at 10:22

This could be a really good solution if you have the possibility of increasing the gain however how about when you capture a vox ac30 with the volume 100%? or a treble booster in which you don’t have any controls and the gain is already set to max by default?

Hopefully they will fix this soon as makes life really hard if you just need an specific tone cloned