Bias FX and JBL 305 Studio Monitors - Distortion

  • I am having a frustrating problem with my rig where I am experiencing pretty significant distortion, even at what I would consider relatively low volume levels. When strumming lower notes such as the open E or A strings, I hear a sort distorted/broken-up "residual" sound after the notes ring out. Because of the type of sound, it is most noticeable when playing clean tones. I can drive the speakers much louder with streaming music, the distortion is only with my guitar.

    My setup is: PRS SE Custom 24 (85/15S pickups), Focusrite 2i2 Interface (balanced 1/4" cables), MacBook running Bias FX, JBL LSR305 monitors.

    1. Over the weekend with some suggestions from more experienced people, I was able to dial out a decent amount of the distortion by adjusting the interface gain, guitar volume, input/output on Bias FX, etc. I now can get to a higher volume level than I was initially achieving, but it is still at what I would consider relatively low.

    2. I moved the speakers much closer to me, from about 8' to about 4’, and further away from the wall. This changed the overall sound and imaging, and also gave me additional volume by virtue of being closer.

    3. Using an SPL meter, very unscientifically, I am able to get my guitar level to about 80-82db comfortably. Once I get above that point, I am getting the distortion/buzzing.

    So my questions...

    1. Is 80-82db a realistic expectation for Bias FX using studio monitors for guitar? It is "loud enough", but I am having to play in a relatively confined space.

    2. Would I be better off with something like an Alto TS210 or TS210 monitor? And if so, would that type of speaker produce quality sound for backing music in addition to the guitar amplification? I don’t particularly want to get a traditional guitar amplifier as I really enjoy using Bias FX. But I could just go with something like a Yamaha THR10 and use the USB connection with Bias.

    Thoughts? Thanks a ton in advance!

  • A2


    if your gain input does not clip the audio interface or the input level on bias fx and you don't have such problem with any other audio source (keeping the same volume settings) the output level from bias fx may be too hot. if it's too hot you should hear distortion from the speakers regardless if the monitor level from the scarlett is set high or low...

    if it is the case, then you should set the output level on bias fx lower...until it doesn't clip anymore.

    so the first step is to fix the clip thing.

    maybe it is just the scarlett which can't handle that amount of gain..

    then, if you think that the volume you get is still too low you may want to increase volume from the speakers (your model results to be active) and from the scarlett (monitor output) that point is just a matter of power of the speaker and the scarlett

  • @salvatore-di-piazza

    Thanks, Salvatore.

    I've done those things, including adjusting the volume controls on the speakers themselves. I am not clipping the 2i2 input as it is always green, and the level indicators in the bottom left and right corners within Bias FX are never red.

    Still, the max I can get under the different scenarios is the 80-82db level. So it is quite possible that is the max these speakers can handle.

    Maybe my expectations are out of line for this type of speaker???

  • @johndagostino If I'm understanding you correctly, your basically using your monitor speakers to get loud playback volume of your guitar through Bias Fx? You could be pushing your powered monitors beyond they're capabilities, or your driving them with too hot of a signal from your interface trying to compensate for more volume...which your monitors are more than likely unable to produce at this point.

    If your output levels are maxed on the back of your powered monitors, and your feeding/adjusting your input signal to them using your interface, I think you are experiencing clipping distortion which is caused when your interface output signal is to Hot. If your monitors are already at max volume, turning up your output signal to its fullest on your interface will often only produce distortion after a certain point because your monitor's amplifiers are out of headroom. If your using an SPL meter, something tells me your trying to achieve some serious volume?

    The more powerful your monitors are, the less you will need to turn up your output signal from your interface to achieve louder volume levels.

    Because your meters in bias, and guitar input meter on your interface are in the green (no clipping), I'm betting your monitors are the culprit as they are underpowered for the playback volumes you are trying to achieve...and this is why your interface signal being fed into them is introducing distortion

  • @johndagostino If my above post is correct, try adjusting the input sensitivity switch on the back of your monitors. If the distortion is reduced or stops completely when you adjust the sensitivity (to say +4db using the switch), then it's your hot signal from your interface that is the culprit in conjunction with your monitor's limited headroom.

    If this helps with the distortion, but the overall volume is still not loud enough, you will need bigger more powerful least more powerful ones which will provide more headroom to achieve the output db levels your looking for...though larger speaker cones will certainly help increase SPL too with the increased low and mid frequencies)

    If your using near field monitors to replicate the volumes heard from real guitar amp/cabs, you are probably going to have issues...but the larger the speakers in the monitors and more power their internal amps have, the better off you'll be

  • A2


    I quote you entirely

  • I have these same monitors. It's worth noting that, while they can indeed get pretty loud, they are not designed for the same decibel levels as stage speakers and will not hold a candle to those in a war of loudness. Studio monitors are after all intended to be used at lower volumes; loudness is not beneficial to production.

    All that said, I have blasted BIAS and other media through my 305s at max volume and not noticed any distorting whatsoever. Granted, I use them with the 310 subwoofer, which could be assisting in that endeavor. Either way though, if you intend on competing with other guitarists with real amps, or just want to reach remotely the same region of loudness, studio monitors (especially smaller ones with 3-5" drivers) will not get you there. That's not what they're made for.

  • Turn the monitors off and plug a good set of headphones into the interface. Do you still hear the noise? If so, it is something in the interface, a ground loop, or other noise issue than levels at the speaker output. It should be easy to check. My house has noisy wiring for example. :frowning:

  • All of you have been very helpful...thanks!

    1st, to answer Elric's question, through headphones everything sounds amazing. The output to the studio monitors is my concern.

    With your guidance I was able to get higher volume and less distortion from the monitors. The change that had the most impact was the to the Bias FX input and output settings in the lower left and right corners of the interface.

    What is odd to me is that I have to set both to 1-2 "dots". I suppose if it works better it works better. But I was surprised to have to venture down so low.

    So while I do get more clean sound, the overall volume of the guitar is just OK. I'd say it is somewhere between normal TV viewing level and "hey, that's on the loud side, can you turn it down a little". It is certainly not "rocking out" level at all. And I completely understand that I am likely not using the right tools if I want more noise (trust guitar playing is noise!). I read about so many people using studio monitors that I made the assumption that they'd be loud enough for home use (no gigging needed).

    While I don't crank it up too often, I do like having some fun and blasting away when nobody's home. And I really love using my computer, interface, and Bias FX as my amp and effects solution. Primarily because I often play with backing music and online resources, and it's all easily controlled via my laptop.

    So, are there recommended alternatives to the JBL 305 monitors? I am guessing that any "consumer" monitor, without going to major expense, would have the same constraints. I could use a traditional amp, but as I said, I like the amp sim method. Would something like an Alto TS210 or TS212 be a better choice?

    Thanks, John

  • @johndagostino I should clarify: 305s most certainly are loud enough for bedroom/home jamming. You should totally be able to play through them, loud enough to not sit in front of comfortably, without them distorting. I was just noting that you shouldn't compare them to a real guitar amp+cab which can get way louder. If you can't even make them loud enough to enjoy playing through, perhaps something is indeed wrong somewhere.

  • @johndagostino Did you adjust the input sensitivity switch on the back of your monitors like I suggested? This really appears to be signal clipping into your monitors from your interface or something in your monitor's internal board is not working right. You should have no issues cranking that model of monitor to volume levels far beyond any tv I've ever heard...and without clipping distortion.

    If your having to adjust the output in bias to clear up distortion, even after the bias output during the distortion was in the green (no clipping), that's just another way of lowering the input signal that eventually goes into your monitors. Your just lowering it at the source instead of the interface. You should be able to achieve the same effect just by lowering your output signal/volume on your interface. This is NOT a software issue. I can Guarantee this to be true because you already proved that by doing the earphone test @Elric suggested. Matter a fact, your interface seems to be fine also based on that test.

    This test is important: Try setting the input sensitivity switch on the back of your monitors to +4db (if you haven't already) and then try turning the volume up again on the interface and listen for a difference. If it distorts again, and at only high tv volumes, I can only assume that your input stage or amplification circuit is messed up in your monitors. I think this because the distortion is being introduced at a much lower output volume than what those monitors are able to produce/handle.

    I have a set of PreSonus Eris E5 monitors that are capable of being so loud that my Neighbors have heard me playing guitar and playing back mixes (though I seldom ever use these volumes in everyday usage). Point is, they are crystal clear at these volumes and your model should be able to crank up without the issues your having. I can't insist enough to try the input sensitivity switch on the back of the monitors and to make sure your monitors output levels are maxed out on the back for this test. This will at least help you to further narrow down the issue.

  • @ash-wolford

    You say "loud enough to not sit in front of comfortably, without them distorting"...not by a long shot (when playing the guitar).

    I actually used an SPL meter, and admittedly very unscientifically, measured that I can only get to 80-82db before the distortion when playing guitar. Playing music via iTunes, Youtube, etc. sounds great and LOUD. I just measured from the same seating position at 98db and they sounded crystal clear.

    I was thinking it could be residual vibration from the guitar/fret buzz. But when using headphones, they sound great.

    I guess the only thing I haven't tried is the cables from the 2i2 to the speakers. I am using 1/4" balanced TRS cable. I did try different power outlets which I know to be on different circuits.

    Could it be cabling??????

  • This post is deleted!

  • @anthony-newcomb said in Bias FX and JBL 305 Studio Monitors - Distortion:

    @johndagostino said in Bias FX and JBL 305 Studio Monitors - Distortion:


    This bit of info right here changes everything...not sure why this wasn't mentioned earlier on.

    I'm scratching my head right now as I'm at a loss for words... If nothing is clipping on any of your metering (guitar input on interface all the way to your output of bias), and your monitors are functioning perfectly for iTunes, YouTube playback, then I am out of ideas...

    ME TOO!!!!!

  • @johndagostino
    Wait a second, I think I know why your YouTube and iTunes playback is distortion free, and why I'm almost positive it's the input sensitivity switch on your monitors that needs to be adjusted because your monitors appear to be fine!

    To test my theory, first turn your interface output volume down all the way, then turn all the volume sliders up to max in the music/video apps. Now turn your output volume on your interface up gradually and see what happens...any distortion occurring?

    If so, it's because (Now) your overall system volume is at the same output level for the music/video apps as say your standalone bias or daw (which bypasses your computer's system volume and only utilizes or depends on the interface...and those programs on average, are technically closer to -0db output most of the time and we use our interface's volume to adjust playback volume). We tend to rely more on the 'system' volume sliders in our music/video apps to adjust volume, or only turn them up part way before using our interface volume thereafter.

    If distortion was introduced after doing the steps above with your music apps, than I suggest that you keep your main computer 'system' volume maxed (YouTube, iTunes etc.) when using your interface for playback and (just before clipping) with guitar software volume, and turn the sensitivity on your monitors down to +4db as instructed in your manual as to eliminate distortion from hot input sources.

    This is the only thing I can think of that makes any sense to me. I'm no expert, but I've got a lot of experience with computer and software audio setups.

    Not trying to be preachy here or insulting, just trying to help.

  • @johndagostino

    IMPORTANT! I meant to say (+4db) on the sensitivity switch on the back of the monitors! Set it to +4db

    Sorry man, I corrected all my posts lol. Oh I feel silly as I just wasn't paying attention...really trying to help here, lots to type so I got ditzy lol

  • @anthony-newcomb

    Thanks,'ve been super helpful. And seems you are like me...obsessive. I am so committed to getting this solved! I am pretty sure it is "settings" based and not a defect in any of the hardware (except maybe my guitar??? See below.).

    In fact, I did dial in a bit of improvement this evening by lowering the global input and output dials in Bias FX and Bias Amp.

    However, I also plugged in my acoustic/electric and found that I was able to get substantially...very substantially...higher volume with no distortion as compared to my electric. With the electric, using the SPL meter, I am hearing the break up starting at about 83db. With the acoustic, I was able to get to about 91db before hearing it.

    Does this point to the issue maybe being related to my electric's pickups? String action? Possibly fret buzzing or feedback?

  • @johndagostino Does noise level change when you touch the metal on the bridge or jack of the instrument?

  • @johndagostino Well I hope you get it sorted of luck!

  • out of curiosity, and for comparison's sake, how are you testing your db levels? what distance are you placing your db meter from the speaker, etc, i'm curious to see how mine compares.