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D. Tone has digital clipping

Below are step-by-step instructions to determine the exact source of the clipping and eliminate it. For more info on the types of clipping that can occur in the Pod, see the "clipping" section. This covers every area where the tone may be clipping, including input clipping, digital signal clipping, effect clipping, "digital clipping" on "full" amp models, and clipping external devices. Additionally, you may want to read the gain staging or the elusive clean tone sections

. Note, it might not sound like digital clipping if you are using a guitar amp and speaker cab, rather than running "direct". If something isn't right with your tone, you may want to give this section a read just to make sure this isn't your issue.

  1. Start by verifying all your cables and guitar electronics are not an issue. Plug them into something else and verify you get a solid, clean tone from them - no pops, cracks, grit, or filtering in the tone. once this is verified, only plug in one cable from guitar to pod guitar input. Use headphones to monitor the output. Keep the big knob labeled "Master" on the Pod at around 20-40% - most headphones will be plenty loud at this volume. If you have high ohm headphones, you may want to turn them up a bit more. Just don't push them to the point where they might be distorting as well. Finally, verify you are using the correct power supply - using the wrong one might get you a signal, but it can be all messed up tone-wise. This eliminates false positives for the tests below.
  2. Verify you do not have input clipping. Set the pod's signal chain to have all null effect blocks and "no amp" selected. Verify the mixer levels are 0 db and panned hard left/right for each channel. Set your pickup selector to your bridge pickup (unless you have a louder one) and strum the guitar about as loud as you'd want to play it. Lower the guitar's volume knob and try again. Repeat. See if reducing the guitar output level cleans up the signal.
    • If the clipping doesn't clean up and you are 100% sure the issue isn't your guitar's electronics or your cables and you're not driving the headphones too hard, something is wrong with the Pod. Try a factory reset, then re-update the firmware and try again. If the issue persists, there may be a physical issue with the Pod or with the power supply. Test with another power supply if possible. If that's the issue, replace the power supply. Otherwise, you probably have to have your Pod serviced.
    • If the clipping cleaned up as you lowered the guitar volume knob, you were overloading the pod's A/D converter. The best way to clean this up is to lower your pickups. You can also try using the pad switch, but i find it doesn't do very much and changes the tone in a bad way IMO. You can also change the input impedance settings to lower values, but this will likely change the tone, perhaps in a way you do not like. The final option is to get some kind of pedal that will allow you to lower the signal level before reaching the Pod. Any other tweaks in the Pod will do absolutely nothing to dial out input clipping. Tweaks such as changing Input 2 to Variax happen after the A/D converter, after the tone has reached clipping.
    • If you are using external effects in the Pod's effects loop, you should test whether you are overloading the effects loop return A/D converter the same way. While the Pod's software does provide receive level controls, I do not know if this control an analog attenuator that buffers the signal before reaching the A/D converter or if it is a digital algorithm implemented afterwards. If the latter, the clipping will be in the signal before reaching it, and the clipping cannot be dialed out at that point. The best way to eliminate this is to lower the final output of the last effect in the external chain.
  3. Verify you are not clipping external gear. If you have effects in your effects loop, try to send a rather weak signal back to the Pod by lowering the output of your last external effect to verify that you're not clipping the effects loop return input on the Pod. Then lower the effects loop send level on the Pod and see if any clipping present cleans up - this would indicate you were previously clipping external effects. Also try testing each external effect one at a time. This issue might be one of the external effects clipping another one, which has nothing to do with the Pod.
    • If you are connecting the Pod to a real amp using a 1/4" unbalanced cable and are running to the front input of the amp, you will likely get clipping unless you set the line/amp switch to amp and are conservative with the "Master" knob. If you are running into the amp's effects loop return/power amp in, you can give it more juice, but you can still clip a buffer for such inputs. If the tone becomes nasty when you move from the headphones to the real amp, try dialing back the Master knob to see if the tone improves. Same goes for running to a PA/mixer using XLR outputs.
    • If you are connecting to a DAW digitally (SPDIF, AES, USB), verify in your audio interface that the levels are not clipping the DAW. SPDIF has send level controls in the system menu. For USB, there is a control panel for the Pod HD driver you can pull up in your computer to adjust the USB volume. I think the default is +18 db which seems ridiculous - turn the boost off. Generally if your Pod isn't clipping, your DAW shouldn't either - they should have a matching digital signal resolution. Don't worry about sending the DAW a super strong signal - even if it's quite weak you're not losing any precision since it's a digital floating-point, signal. Boosting inside the DAW is the same thing as boosting inside the Pod.
  4. Start adding stuff to your signal chain while verifying you are not exceeding the Pod's internal digital resolution. Anything in the signal chain that affects volume has the potential to push the signal's amplitude beyond the precision of the Pod's digital circuitry. I believe this is 24 bits, which is quite large. The two obvious ones are the Amp/Channel Volume (Volume Knob) and the Mixer levels. But many other things will boost the signal as well. Delays and Reverbs can add a little volume. The Mid-Focus EQ's default settings heavily boost the signal, and any of the EQ's can boost the signal with certain settings.

The Pod uses digital algorithms and a digital signal. Unlike analog circuits, where you want to gain stage each piece to near clipping to get the best signal-to-noise ratio, the Pod can convert from low to high and high to low signal levels without losing precision or adding noise. So it's best to keep the signal level conservative, far away from digital clipping.



  1. Be aware that certain effects in the Pod will clip even if you aren't clipping the overall signal level. The Parametric EQ is particularly troublesome here. Try toggling effects on and off and see if the tone improves and if the problem is related to overall signal level or a particular effect.
  • Maximize the tone for analog outputs, if applicable.
    • You want the signal to be as loud as possible at the end of the signal chain (without clipping as mentioned above), before it is converted from digital to analog, in order to get the best signal-to-noise ratio. But if the patch has a Parametric EQ behind the amp, this means you have to keep the amp volume knob conservative to avoid clipping it. I do one of two things to work around this issue. For a mono single-amp tone, I put all my post-amp effects after the amp but before the Mixer. I use the Mixer to boost the signal level and pan to center for that channel, and I mute the other one. If I want a stereo tone or dual amp tone where that option isn't available, I try to put a Studio or Mid-Focus EQ as the last effect in my chain and boost with the Gain parameter (this has no effect on how much EQ'ing is happening). I get as close to clipping as possible, and I test it with a few different guitars and style of play to make sure no aggressive playing or certain notes don't push it into clipping.
    • You want the Master knob to be set as high as possible to achieve the best signal-to-noise ratio, but you have to balance this against clipping an external device. Follow the same guidelines as above - you definitely want to be below clipping but try to get it as high as possible.
  • Certain full amp models model crossover distortion in their power section such as the Blackface Dbl, AC15, and AC30 models - it sounds similar to digital clipping. I find the best way to dial this back without altering tone is to use the DEP (deep editing parameters). Turn Master down and Bias X up. Other methods to reduce the clipping is to reduce the amp Drive parameter, change Input 2 to Variax (or Mic or some other null input), or put a Studio EQ in front the amp model and turn down the Gain parameter. See here for more details.

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E. Tone is muffled

For a "direct" setup, most cab and mic combinations sound muffled for high gain. Simply turning up the treble might not do it. Use all your EQ options at your disposal to dial in the high end. (See "EQ" section)

Note that trying to dial in the high end for an amp/cab/mic combination that happens to be very muffled-sounding will just give you a very noisy high-end that sounds artificial or processed, or fizzy. Dialing in frequencies that were never there to begin with means you are just amplifying noise. Thus, cab and mic selection is important.

I usually use the SM 57 off axis mic, as it sounds the most natural to me, with rich mids and highs. But you may want to try the SM 57 on axis mic; it has the cleanest and brightest high end.

My favorite cabs are the Hiway, Treadplate, Greenbacks, Uber, and XXL 4x12's. Of these, the Treadplate is very bright, the Uber, Hiway, and Greenbacks are relatively balanced, and the XXL is very boomy. I like to use parametric EQ's to neutralize the extreme parts of the cabs, and/or dial in the mids. See cab and mic selection.

For a "live" setup, I like to use "no cab" as my cab. Even if you do not use "Studio/Direct" output mode, selecting a cab will use "live-voiced cabs" (see "output modes" section). These tend to reduce the high end. Also, the "pre" versions of the amps tend to have more mids and less high end, although I wouldn't consider them "muffled" - you just have to EQ them a bit differently. Just because you are using a real guitar power amp doesn't mean you're guaranteed to prefer using the pre-amp only model more than the full model (see full vs. pre).

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F. Distortion is muddy/fuzzy/farty

I have to wonder if Line 6 modeled these amps using a guitar with really bright pickups (or vintage pickups with low bass response). When you use what I consider "normal" or "full-range" pickups, the distortion tends to be a little dirtier and fuzzier than tight and djenty, even on the high gain amps. If you fall into this category, you can use a distortion effect as an overdrive or an EQ effect before the amp distortion to pre-eq the tone you send the amp, changing the way it distorts. See this section for more.

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G. Distortion is dirty/gritty

You may want to sculpt the tone before your distortion stage. See this section for more. Sometimes you want to send the amp more of a mid-range than high end peak frequency range to get a smoother distortion. This is particularly the case for power amp distortion with the Park 75 and JCM-800 models. If you turn up the presence control too much, you may notice the distortion seems to go splat or get real nasty, even on a single note high up on the fretboard that should be smooth and sing. I usually turn presence to 0% on the Park 75, because this is so bad. See the this whole page for more.

Also, note that the "pre" versions of the amps tend to be a little cleaner than the "full" version as far as their distortion character. While I prefer to use "full" amps and use EQ's and distortion sculpting to dial in my tone, it may yield better results for you to try out the "pre" amps. (see full vs. pre)

Or you can try turning down Master Volume or playing with the Bias DEP's on the full models. These can often reduce the dirtyness of an amp model's distortion and smooth it out.

You can also get some nasty distortion sounds if you try to chain multiple distortion phases. In the Pod, you can have a distortion effect distort, than the amp model's pre-amp, plus the amp model's power amp. If you're using a real amp and speakers, both of these can distort as well. Having serious distortion in more than one of these is likely going to create a nasty distortion tone. See layering distortions.

Similarly, if you are trying to use two distorted amps as a dual amp patch, and have them both panned to center (or both left or both right), they'll likely produce some kind of comb filter effect and sound pretty nasty. (see "dual amps" section).

Finally, you may be getting input clipping and your distortion is making it sound like a nasty amp distortion rather than digital clipping. See if your tone has clipping when you turn off the amp model and other effects. (see the "clipping" section)

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H. Tone is thin

I find the "pre" versions of the amps are a little "thinner" sounding than the "full" versions, and tend to use the "full" versions, even if I'm running my setup "live" (through an amp and guitar cab). They tend to have more bass and just sound a bit richer. (see "full vs. pre" section)

If that doesn't help, see I tried this and it doesn't sound good. You may have an unconventional setup, and you might want to try Studio/Direct output mode and cab+mic simulation, even though you're running through an amp and speakers.

For "direct" tones, I like to use the SM 57 on/off axis mic, but find this can leave the tone a little thin. I compensate mainly by boosting the bass and/or low mids with a parametric EQ effect (freq at 15-30%). If this creates too much "thump" or ultra-low bass, I will EQ that out with a Mid-Focus EQ effect. I find this works better than using a Dynamic mic, which already has lots of bass dialed in, but that's another option. See the mic selection.

I also developed a "dual cab" method to try get the best features of two cabs that excel at opposite sections of the frequency range. See Dual Cabs.

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Date: 2016-01-03; view: 669


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