MartinDorr

I can't say whether this applies to DeanDinosaurs use case, but the Studio EQ seemed to stay very clean and tone neutral on any dialed in gain level I ever used, except when its input or output level exceeds -12dBFS. Initially the Studio EQ just soft compresses a little but at around -6 to -3 dBFS and higher you will hear serious distortion creeping in. I suspect that Dean's experience with the Studio EQ after the Amp may have been at higher signal levels. Another thing with the Studio EQ is that it claims to add gain in 0.1dB units. Don't be fooled by the precision of the dial. It may be 2dB off from what you dialed in in the -9dB and +9dB ranges. ... and if your input or output is above -12dBFS it won't give you the dialed in gain either. The higher you go above the -12dBFS the less you will get even though you think you added clean gain. If you're just after a little clean boost both the Studio EQ and the Mid Focus EQ will do. Both of them don't stay clean if your input or output is above the -12dBFS signal level. Not sure about your reference to amp's gain. If you refer to Drive, boosting your input signal before the Amp does something very similar, but while the EQ's can provide a clean boost, the Amp model's gain via Drive will be colored to match the real Amp's Volume or similarly named dial. Don't get confused by the Amp's Channel Volume dial name. This thing does not model the Amp but is simply a clean AMP model output level adjust dial. Unless the Amp's output signal is above -12dFS (yes the magic -12dBFS is back) channel volume can be used to adjust the Amp's output signal by 60dB. If you half any Channel Volume % you get approximately 12dB less output, e.g., if you start with -24dBFS at 50% you can get -12dBFS at 100%.

I think the cleanest, most transparent, and highest boost you can get is using a Mid Focus EQ (+24dB max). For every 10% you get about +2.4dB, i.e., +12dB at 50%. Use HP Freq 0%, HP Q 55%, LP Freq 100%, LP Q 55%, Gain 0% for clean pass through But watch the resulting output level. Measure if you can (e.g., with USB and a DAW meter). You will get soft compression starting at -12dBFS and distortion if you approach -3dBFS or higher. It is generally a good idea to keep input and output levels between HD500 models below -9dbFS to avoid unintended distortion. If you want a high clean output level, put the mixer at the end and you use its gain (+12dB) for clean boost above -12dBFS. Obviously, the volume pedal is a better choice if you need to adjust on the fly.

In regard to Cab sims, you can view them as a combo of multi-band, hardwired parametric EQs and compressors. The same applies to mic sims. ER is a simple form of delay emulating the first reflection of sound in a room. My point was that you may want to try them and see what you like and possibly create room for other effects in your chain if they can replace them. It does not really matter what those sims where designed to do as long as you like what they do to your sound. Don't get limited by the fact that you have a real amp and a cab and that their presence excludes HD500 features that seem to do the same or something similar.

Also, while you stated that you do not want it, you can turn cab (ER and mic) sim on for preamps. I know it's a little counter intuitive, but it might be worth trying as a replacement for a dedicated EQ or a little delay source if you run out effects.

Thanks for all the tips. Current status is that I was able to break down the problem into 4 contributing factors: 1) Inexperience in how to play high gain sound melodies, e.g., sloppy tying of notes w/o significant re-triggering causes some wild effects (and gurgling) 2) There are naturally occuring (and modelled) sound effects of the selected amp (both good (if you know how to use them) and bad (if they surprise you)) 3) New strings and tighening loose lock nut pegs have an effect on tone ring out (surprised? not really - I should have checked). 4) There is still something going on in how my G string rings out (seems like a whole bunch of frequencies fade out quickly after about a second (not clear whether they should have been there in the first place) and this seems to increase the gurgly character of the G string sound. Overall it's definitely better, but because I can hear the ring out differences on both clean (no amp) and overdriven sounds I suspect there is still something yet to be fixed in my guitar mechanics though i have no clue of what else to check for looseness, dirt, or whatever. Everything feels solid and dampening anything I could think of did not change the outcome. The action is not low either. ... and I have a Korean JTV-69, HD-500, DT-25 Combo (someone asked earlier). Did not use the DT-25 for the experiments to minimize the variables. Maybe the Korean build quality is biting me ... Appreciate if you have any further tips on what to check.

I tried (a re-tried to be sure) * Variax piezo (worst) * Variax mags (better but still there) * Analog mags (better and better hidden by signal noise) I'd guess this means that its maybe some resonance effect most noticeable on the G string and most amplified with an overdriven amp model. There is a little bit of the effect on some notes on other strings, but the G string is just aggravatingly bad. So bad that you really don't want to hold a long note in the region where its worst. Damping? where to start? something else? Magic? Hoping for ideas

Good point, haven't done that yet. Should have thought a little more b4 posting ;-) Thanks

Looking for cause. When using mid to high gain sounds I noticed by G string notes starting on about fret 10 and higher have a strong 'gurling' sound effect. I am guessing at some resonance in the guitar mechanics or a faulty piezo as reasons, but really have no clue. Sorry if this was discussed before. Tried a couple searches but could not find a hit. Appreciate any advice on how to zero in what's broke or even better, a fix ;-)

I suspect that the POD does not have 2 sets of DA converters for balanced and unbalanced outs, which it would need if you want to deliver different digital signals to the 2 types of output. This is probably not a matter of 'just DSP SW'.

Depending on what kind of input signal you use (native guitar signal, a little boosted, or heavily overdriven) and the Drive setting on the amp, a 50% channel volume may not be low enough to keep you out of compression/distortion territory. If you have any way of measuring (e.g., via USB and DAW meter) my advice is to keep below -12dB input or output on any model except the mixer. As radatats described, the channel volume know of the amp is tone-independent, BUT only if you stay below the -12dB level. If you go higher you initially just get a little soft compression (which may not be bad for what you want tone wise anyway) but at about -6 to -3dB you will hit distortion, more or less hidden by the tone you're going for.

Thanks for feedback. Happy to see that your use experience is matches much of what I figured after playing around for a while. Found that the 100% threshold, 4% level setting is the closest to a fairly tone and level neutral pass through though you seem to get some secret souce coloring you really like. Personally I was a little disappointed by how little the tube compressor does tone- and compression-wise between 100-60% threshold. I had a hard time even hearing that there was a difference in that setting range for my Strat pos #2 loop I used in a blind test (predicting whether the compressor was on or not on) after I compensated for level differences. Will try your tube screamer and amp suggestions. Maybe the right 'post processing' makes it come out more. Other forum members reported that they mainly use the tube compressor around the 50-40% threshold setting. At that point it also gives you a nice 4-5dB boost even at a 0% level. Thanks agian, Martin

Just stumbled of those interesting posts ... Can you share a few tube compressor settings and describe in a few words what you use it for (material, guitar, Amp, compress or compressand + change level)? I just posted earlier today some questions I ran into using the tube compressor. I like the sound but the model seems to behave a little 'unexpected', i.e., it adds gain at 0% Level for Thresholds starting at <70% (about 13dB at 0% Threshold) Thanks, Martin

Started to dig a little deeper into how to best use the Tube Compressor. Found that conservative settings produce rather subtle and a bit surprising results in level changes. Have no idea how the real thing is used and how the controls translate. It seems the Level parameter is just an output gain makeup adjustment whereas the Threshold parameter is either the same or similar to the 'Gain Reduction' on the LA-2A. I noticed that I have to set Level at 4% for thresholds 100-70% to maintain my output level, which is surprising because I would have thought that the more i compress the more I need to raise the makeup gain level. Starting at 65% threshold and down at 0% Level the compressor output actually went up starting with about 1.3dB for every 5% Threshold change and ending with and increase of 0.5dB when Threshold is changed from 10% to 0%. I would have expected that I'd have to increase the Level to make up for Gain Reduction. I ended up being able to only compensate for output level increase till about 60% threshold. From 55%-0% my level went up by 13dB on extreme 0%Threshold setting. How are you using this effect, what settings work for you, any other interesting things you can share? Thanks Martin

Can't say whether it applies here but I found that all preamp models and the Studio EQ as well as the the Mid Focus EQ start to distort for any setting where the input or output is or gets significantly above -12dBFS (measured via USB with a DAW). I suspect that all HD models except the Mixer and possibly VolPan behave like that. A hot guitar input signal may already reach or exceed that level. With my JTV coming in as Variax (digital) I see levels at -12 to -18dBFS at Tone/Volume max depending on guitar model though I suspect the max levels have increased in the latest FW update for some guitar models.

Same impression so far although I did not go back and try to refresh my memory ;-(. Don't have enough experience whether a little EQ-ing can fix it (or was the cause why they stood out for me in earlier FW). Martin

Assuming you are correct you could do a manual comparison (maybe via screenshots) whether the tone settings in the file (the binary encoding) are translating to the same parameter values (what shown in the SW editor or on the HD display) on the HD500 and HD500X user interfaces. You should be able to at least check and compare the 2 editors using both file versions of the 'same' tone if you do not have the HD500 anymore. Would be really interresting if you find a difference beyond it just sounding different. Besides that there could be more HW changes lurking that have not been dicovered by users opening the HD500X enclosure (and not pulished by Line 6), e.g., like a change in AD converters or just a later rev of the AD converters installed in the HD500X. Just wildly guessing ... Martin

You may want to check whether you are feeding an input signal to both signal paths, i.e., Input2=Same.

Thanks for digging this up. It's always good to come here and learn an extra thing or 2. Sorry for any confusion my earlier comments may have caused. Martin

I vaguely remeber having read that the external pedal can be calibrated just like the internal pedal. Unless you already did this you probably need to lookup the pedal calibration procedure or search for a member contribution. Good luck.

Thanks for the update and nice picture posts. Now everything is much clearer.<br /><br />Because you used USB I am not concerned about calibration. You may want to check into any SW driver default dB adjustments though to make sure you captured the 'real deal' and not some adjusted numbers (my OS-X drivers and DAW played that trick on me before I discovered weeks later). Compared to my JTV measurements your guitar input level experiment measurements seem low, but I have never measured using the analog guitar input on the HD and everything may be quite normal.<br /><br />I am just not so sure about the clipping you think to see. The screen shot shows levels in orange and red if they exceed -20 and -10 dBFS, respectively. I don't think this means that they are clipping in the digital domain. They are just exceeding some meter display thresholds. I don't know anything about your SW, but it may simply be a meter setup that causes the coloring and not a sign of real clipping. Whithout knowing more (e.g., cut-off level plateaus when looking at highly zoomed in waveforms) I would not have assumed that you ran into real clipping because you did not hit 0dBFS. On the other hand there are 2 peaks captured that exceed my assumed -12 dB threshold and I would thus assume you may have run into slight soft compression for those frequency bands (all assuming my threshold theory is true for all models).<br /><br />What might be interresting to check is what peak levels you get when you turn effects off, one by one from right to left if you are concerned about adverse tone impact due to compression. You could have somewhere in between a transfer that is higher level than the final output signal. If true, this model to model transition would have likely more impact on your tone than the final level you get. Not sure how much more time you want to sink in to this (I got kind of tired measuring rather than playing when i did this ;-), but if you do you might get some insight into how to keep the signals in a healthy range all the way through your amp and effects chain.<br /><br />I would not want to spend my life constantly checking sound changes via measuring, but it's nice to have a backup method to check if parameter changes just don't seem to sound right.<br /><br />Again, thanks for posting your results. Was very interresting (at least for me and apparently you ;-).<br />Martin

If I connect my JTV via VDI as input 1 and set input 2 to Aux with nothing else connected, no amp or effect models and mixer set to 0dB I can measure a noise floor of < -92dB via USB. Like Rewolf said, a lot depends on your input signal quality and level. I don't think the HD unit itself has any inherent noise level that would prevent you from getting very clean output. But having this out of the way, there are plenty of possibility to bring in or produce noise throught inputs, effects loop, or just bad amp and effect model parameter settings. Martin

Thanks for feedback. Couple questions to put this in perspective with my own measurements and possibly other member's situation if they do this experiment too. It looks like you did not mute one of the A / B channels in the mixer. If you do, you should see 6dB less output level. So dependent on what you do with mixer in your presets (and where the mixer is in your effects chain) you may not compress the tone as much as you may think when the output hit -3 to 0 dB. Can you confirm that you muted or not muted one of the channels in the mixer for the experiment and what your mixer does and where it is in the presets? You did not mention the input setting. If you did not follow my description (not to use Same for Input 2) let me/us know. No using Same should lower your guitar input signal by 6dB in the experiment. I assume from your description that you did not use USB and one of the analog output options to measure. I have no experience with that and can't tell how the DA conversion and line level conversion impacts volume levels. In other words, it is not clear at all whether you exceeded the internal digital threshold (e.g., my assumed -12dBFS) even though the analog signal you measured was peaking somewhere between -3 and 0dB. There is also the potential for measurement errors due to uncalibrated equipment and level miss-match problems. I am not saying you ran into these things, but it would help if you can be specific of what analyzer equipment you connected to what outputs, whether the equipment was calibrated and anything else you may have done to asure reliable results. Thanks again for digging in. It's always good to hear what others run into actualling repeating experiments with slightly different variables. I am a JTV user and will try to dig up what I found exactly when doing this and measuring via USB. Too bad I don't have anything reliable to measure what comes out on my analog outputs to compare with the USB results. Martin

I am afraid there is no general gain level that would make sense to know for a number of reasons: For one it is unknown what level range of your guitar input signal is. Second, any effect or amp model you select and dial parameters in will have a different input to ouput level transfer function at a neutral gain setting. In some cases even the default model parameters do not produce a 0 gain transfer function, e.g., Mid Focus EQ. For amps the gain transfer function depends on your guitar input signal level, drive, and channel volume even if there would be a magical 'neutral' tone stack setting (it is not known how the actual amps tone controls are modeled with the models tone controls, some controls are added some are left off). Even if you use a JTV and come in using the digital connection, different guitar models produce different output levels with same volume/tone settings. I think the best you can do (if you want to go about this 'scientifically') is to try and get a feeling of the guitar input level you produce while selecting your favorite pickup configuration and volume/tone controls. If you know that you come in low or high (relative to some choosen peak, e.g., -12dB) you can by default use a preferred first effect model (like a Mid Focus EQ) to raise or lower your signal to feed subsequent models while adjust frequency content (which is often something you'd want anyway) to get specific tones. A simple experiment w/o measuring would be to setup up a tone with no amp and no effects except a Studio EQ (to keep the sound uncolored) at 0 gain and the Mixer at 0dB, left or right channel centered, other channel muted and input 2 set to an unused source (if you use Variac select Aux, if you use guitar use Variax) to get the cleanest and least touched signal through the HD500. If you have a DAW or other measurement equipment see what level you get out and adjust the the Studio EQ's gain so that your hardest hit or strumming does not exceed your target dB level (I think slightly less than -12dB for peaks would be a good target). You should hear no distortion whatsoever. If you can't measure you need to trust your ears, add gain and listen for distortion. If your hear a hint of it I would back off at least 3 if not 6 dB. Obviously this whole process only matters if you want to maximise output and work with the healthiest undistorted guitar input signal you can produce within the HD. Once you have that 'optimal' signal I think you should do nothing in any subsequent model to raise the level. if the output gets louder you probably entered a models soft clipping, compression, distortion range. But remember there is nothing wrong doing that if you want this effect. Sorry to be of no more help. Good luck, and let us know how this works for you, Martin

Check your input assignment. If you have nothing in front of your 2 amps you need to select Same for input 2 so that your guitar signal gets routed to both amps. If you put a mono effect in front it will send its output to both paths and you should hear what you experience. If you put a stereo effect there you should have teh same problem. Hope this is it, Martin

Not sure whether your feedback is in addition to my comments or stating a diverging opinion. By the way, your measurements are extremely helpful understanding what's going on. I just wished I had them before I started looking closer at the preamps and some EQs. My comments where in regard to what the models appear to do in the digital domain. You can easily verify this by doing a few measurements around the -12dbFS input level for say the Studio EQ. If you dial in a +6dB gain on a -18dB input signal you'll get about -12dB output. I say about because the Studio EQ is pretty bad at matching the dialed in gain and it may be up to almost 2dB off depending on what gain you dialed in. But I think this does not matter because you measure some gain and that can be used as your baseline. Now if you increase the input level by say 6dB you will not get an increase of 6dB output but less (and compression as well as some distortion). If you go higher it gets worse. If go lower from the initial -18dB input and the +6dB gain the resulting output gain increase stays the same, i.e., the Studio EQ gets into non-linear model behavior (just like the real thing) when you go above the -12dB intput or output level. Not sure what really happens if you come in high and then lower the gain, but I'd gues the damage is already done by whatever is in front of the Studio EQ. I measured all preamps and a 2 EQ models. They all do this as far as I can tell. Just above the -12dB not much happens but once you push beyond -6dB the effect becomes pretty obvious. Thus my advice is stay below the -12dB on all internal signal paths unless you want that soft clipping / compression effect. If you need more output use the mixer as very last stage to raise your level higher than -12dBFS. Martin