Why Are Digital Pedals So Noisy? (at Least an Awful Lot of Them) 

This is an interesting subject. You asked "how can this happen? Aren't A/D converters better than this?" I have one possible explanation for you. I design chips for job, mostly digital. But the chips are "mixed signal" meaning there are analog and digital portions on the same chip. One of the products had a noise issue that roughly corresponds to what you're talking about. The A/D converter needed 1mV accuracy (it's DC for this case, not audio). The simulations showed 1mV accuracy. But when we got the chip back, it had occasional noise that blew away the 1mV accuracy. We searched high and low and finally find the noise happened only when the chip was communicating digitally with another chip in the system. Internally, the analog and digital were quite well isolated, but I/O buffers for communicating externally coupled noise onto the analog part of the chip. The product had to be cancelled. The manufacturing process didn't have digital and analog isolated well enough. Later on, I've worked on mixed signal chips which were isolated well enough. I don't know about guitar pedals, but it's safe to say that whatever microprocessor they're using will have A/D converters and digital on the same chip. An audiophile grade product would instead have a separate A/D converter chip and a separate D/A converter chip for the output. Costs more money, but it can be done. In theory any A/D or D/A chip could have this same problem, but in that case the converter chips will be specified quite well for noise performance. You know what you're getting.

One issue is the amount of headroom the designers use for the pedal. Although nominally 'guitar' pedals, a lot get used with synths or in send/return loops from mixing desks, so the design generally allows for a lot of input signal headroom compared to what would be required for just a guitar signal (though with distortion and boost pedals, that signal level itself could be quite high compared to a straight guitar signal from say a Strat. The Flint B has 24 bit A/D and D/A converters running at 96kHz. Strymon quote a 115dB S/N ratio for the Flint B. You certainly wouldn't hear that if that were the full picture. But they also quote a +8dBu maximum input signal level. So to get that 115dB S/N ratio, that's where your input signal level needs to be. As the input level goes down, the S/N ratio decreases. 8dBu equates to 1.95v rms. A vintage Strat output signal is around 0.1v. That equates to -17.8dBu. So immediately you are lowering the S/N ratio by 25.8dB, to about 90dB. Even that should be inaudible. To be able hear the noise over a general room background noise level, the actual S/N ratio is probably only 40-50dB. So something else must be happening. Today, even budget audio interfaces costing 1/3 the price of the Flint can manage a S/N ratio of around 117dB (equating to around 20 bits). I expect the quoted S/N ratio is a theoretical rather than measured value (otherwise the unit must be faulty). And with true bypass via relay switching, there shouldn't be any extra noise in the bypass signal. Of course in true bypass, you have got the extra guitar cable length added, which will reduce the amount of treble in the signal but will also allow extra noise to be picked up by the cable. As others have mentioned, layout issues are probably the cause. The jack, knob and footswitch layout defines how the signal will have to run around the circuit board, which is probably sub-optimal for noise pickup. It would be interesting to see how the bypass noise levels compared when using a separate FX loop switching pedal to switch the Flint in and out.

Excellent demonstration of your ability to create outstanding equipment. Thank you.

I have a Flint V1 "black knob" edition, the distinction made only because their supplier ran out of cream knobs, and it's the only pedal I use unless a wah is needed. I have it set to true bypass mode (even though it's almost always on) and I absolutely love it. The slower, deeper harmonic trem of the V2 is intriguing as even on the V1 I can use it as a substitute for a Univibe (think Machine Gun). I bought it because my amp doesn't have onboard reverb and never once have I missed the extra tubes and components of onboard reverb. I briefly had an AC15C1 and used the Flint instead of the onboard reverb. It was just better in every way. Being the only pedal in my chain (in an old house with dubious wiring) I have no noise issues at all related to the pedal. I've had no desire to go down the rabbit hole of reverb pedals. It's a keeper.

Thanks Lyle. Appreciate your efforts.

Thank you for the demonstration mike ehrmantraut

I will certainly look into getting the v2 of the Flint, just for the tremolo improvements. I've had a v1 for years and never been completely happy with the tremolo controls. It sounds great, but the v2 is an improvement. However, in my rig I've never had a problem with the noise floor on any Strymon pedals. Any noise they make is masked by the noise coming from the amp, other pedals or the environment. I will add that the only pedal I ever returned, because it was noisy, was a very recently designed analog delay. As another here comments, power supplies are likely to be a bigger concern with noise problems.

I have the same MXR reverb and it's last in my chain, on all the time. I've not noticed the noise however I haven't played out in years. I'm pretty much living room level these days.

I have a Strymon Iridium and BlueSky. With the Strymon supplied power supplies they are somewhat noisy (especially the Iridium). But with my Cioks DC7 power supply, they are virtually silent.

I have found the same. The JHS Packrat is like adding a satellite dish to my board. I made a 9v battery adapter because it was unusable even with a good power supply. Not a cheap pedal to have such a noise issue.

really good video lyle.

The strymon cases are cool uhhh remind me of the old bud boxes that proco used. But have that 1/2 inch radius.

I hear it here, but with the cymbals crashing, the bass banging away and the singers going off, the noise is negligible, if inaudible. I think, as with most things in life, it’s a trade off. If the noise is a deal breaker, that’s what a return policy is for. If it can be done better, at the same price point, let the free market dictate the fall of strymon. I get where you’re coming from, but in the end, as you said, it’s a tool in a toolbox (really for most of us a toy in a toy box) and used to make music and to inspire your playing. Don’t be sad. Life is too short.

Have you found any well designed and quiet digital reverbs? I have also been disappointed with many different brands.

I own the Mxr reverb and definitely noticed this. Looking to upgrade from this soon

Agreed. Puzzling that more reviewers don’t mention noise, it’s a go/no go issue for me. Would be nice to have a list of truly quiet pedals.

My Strymon Flint, Deco, and El Cap, add zero dB to the noise floor in my rig. Plugging both my amps and my pedalboard into a Furman SS-B makes a world of difference, that is especially noticeable when stacking dirt pedals.

Just returned an AC10C1 because I couldn't get past the level of noise with my digital pedals. I'm mainly into electronic stuff so I've a Zoia and Chase Bliss Habit, neither of which cause any significant issues going into my DAW, but the Vox hissed like bejesus to the point that it was basically unusable to me. Still planning on trying an AC15 to see if it works better with my pedals, but I was pretty shocked - I do feel like the AC10 exacerbated it badly, or at least it's been getting most of the blame, but it seems like it's not 100% the amp's fault either. Thanks for the videos, they're a cut above basically any other pedals/amps stuff on RU-vid.

As a player and recording artist, I share your frustration big time! I have tried all sorts of highly recommended pedals and then I often find the noise floor to be unacceptable. The worst offender so far for me is the Catalinbred Naga Viper. On or off, it is noisy. I tried it with multiple power supplies, battery power, with and without other pedals, and on an Orange, a Mesa, a Fender showman, and a Metropoulos. The Naga Viper is a complete disaster in every application. It's not cheap and the company has an excellent reputation. What gives? I also bought a Strymon El Capistan. It has nice sounds but it can be noisy on my pedal board. No idea why but for the rest of my pedals (the ones that made the cut) I can power them from the pedal board no problem. For the El Capistan, I use a separate power supply cable (not the one from Strymon). Then it is reasonably quiet.

You are right if course...but it doesnt matter on a noisy stage which is where you use pedals, unless you play some stand alone ambient music. Noise floors are important in PA/ studio environments.

I'm with Lyle on this. I've had manufacturers tell me it's a problem with my rig or that I am more sensitive to the noise than most. As a recording engineer, I beg to differ. As an example, the noise floor on the delay side of the Collider was so high that I had to use RX to get it out during the mix. That's a full mix, so even masking from the full band was not enough to cover up the hiss. My board is meticulously wired, powered with a Cioks DC7 and fronted by a switcher that lets me take pedals out of the signal path, so I can troubleshoot easily. Seems to come down to the quality of the AD/DA conversion and whether or not the designer has implemented filtering. For time based effects, I have settled on the UA pedals. They still raise the noise floor, but by an acceptable amount relative to any gain stages. Definitely a trade off when it comes to scale of function. Lyle, the only time I have had a buffer make a difference in noise was with the Wampler Terraform. Without a buffer inserted directly before it, the noise was hideous. Input impedance design flaw but yet again the manufacturer was quick to blame my setup.

Strymon Zuma Powering 12 pedals two are Strymon small box, the MXR M300, Neunaber inspire, DD-200 and drives Very slight increase in noise with them in the signal vs out

Exactly. I have an old mk1 boogie amp and a somewhat creative digital board, when I’m sitting on stage in a quiet show environment my pedal board noise is over the top. Turning it off is not an option as I’ve got to be ready for the next song at any in moment.

Can you recommend a quiet delay? Analog or digital. Thanks!

What kind of guitar was that? Sounds like some kind of Strat? Sounds great plugged into your Excalibre 15! Alao wanted to point out that with modern digital solutions like Line6 Helix, you can have an entirely digital signal chain all the way into your DAW, the only noise comes from your guitar + cable.

Even plugging into one stompbox while bypassed can change the sound. The way it is... Even using good buffers will change it. Not always for better or worse, I've seen it help the sound too.

PCB layout (large current loop area from poor grounding/routing, ground stubs, audio near clock signals), insufficient power supply filtering (especially in switching supplies), insufficient pre/post conversion filtering, insufficient bypassing… there is plenty to go wrong. And each point can influence others. Sometimes even a properly spec’ed ferrite might have made all the difference. Line 6 (Yamaha)/Music Group are definitely burning cycles with EMC testing. Surely harder for smaller operations, but there’s plenty of smart decisions you can make even if you lack other resources.

I recently put together a board powered using a Cioks DC7. Prior to the DC7 arriving I had everything powered using separate adapters (mostly the ones that the pedals came with). In theory things shouldn’t have been any noisier but they were.

One thing I have found is that the V1 Strymon pedals are basically silent but the V2 versions add hiss.

Sorry, perhaps a stupid question, but what do you mean with "trails mode"?

Man, there’s so many pedals that have noise issues, analog and digital. I’ve only tried one strymon pedal, the sunset overdrive/boost. Immediately hated it as soon as I plugged it in and returned it. Just didn’t sound right on any setting to me. Right now the only noisy pedal I have is he analog Mxr phase 95. Is a great phase, but man it’s noisy as hell on my pedal board with an isolated power supply…. Still really want to try out the strymon flint v2 though..

Do they put the bypass through the ADC/DAC I wonder? Aka everything is done digital....

With the amount of noise my Big Muff makes with the single coils in my Jazzmaster I don't think I would ever notice a little hiss from my reverb. Maybe in recording, but in that case I can't imagine why you wouldn't add time-based effects in post, especially because that would give you more options for blending the wet signal when you get into mixing. It's annoying for sure that digital pedals produce noise, but I have to think that it's a compromise for hitting a size and cost target. You could probably have a totally noise free reverb pedal, but the cost would probably be totally prohibitive for everyone besides studios and blues lawyers.

Interesting, as a small gig player, Ive never realy noticed noise increase apart for overdrives/fuzzes. To me its like having a fantastic boutique amp or a reissue / budget or even modelling amp, once the drums and bass and vocals kick in any extra 10% is instantly lost. If I was doing a recording however, I can see the concerns over extra noise.

What about something like a Revv G8? The G8 has 4-cable method capability.

I was a huge mxr and DigiTech fanboy. My '82 distortion+ isn't crazy loud for where it's set, bought a newer one (which looks completely different inside) it's noisy. For whatever reason the fx loop fixes most the DigiTech noise. But I've sold several mxr pedals due to noise I have a Timmy, which is a good sounding box but has a defective input already.. and I don't even gig. Tc and ehx are great used pedals and I should've looked at them earlier. I mean ehx makes anything you might want ..

When you strum the guitar the 2nd time at 2:59, It sounds like that scene from The Doors movie, as Jim wakes up from sleeping on the table at the birthday party, just before leaving for Paris...

I found the new mxr Tremolo gave off microphonic noise , not hissing but actual high pitched when engaged, i have had similar problems with looper pedals RC 2 and RC 3 + Digitech Jam Man, all 3 were the worst and unusable in a gig situation.

Just curious, but what power supply are you using? I know you mentioned it’s isolated and provides enough current, but many digital pedals seem to be really picky about power supplies. We all know the little “OneSpot” style supplies are noisy (especially the ones that Strymon include for free), but even the toroid transformer style I’ve found to be less than ideal with high current digital pedals. I upgraded my trusty old VL Pedal Power 2+ to a Strymon Zuma a few years ago and it made a noticeable difference in the noise floor.

Your Trem comparison on the Flint(s) was done using different Trem types, '61 on the New pedal and '63 on the old one. My Flint has no noise issues in the FX loop of my amp.

Valid and accurate comparison!... So I believe that part of this noise problem is the quality of the semiconductor (active) components or resistors, capacitors (passive) components used in the manufacturing process (both discrete and integrated). Manufacturing = costs so either they chose cheaper components (higher internal noise) or the design used some components that were available at the time of production that had a higher internal noise. In short it comes down to money and/or what is available at the time of manufacturing. Did you use the best components for audio when u built yours? Cheers and thanks for the good work you put in your channel!

I suspect differences in their grounding schemes, between the different brand pedals.

In my experience, having tried dozens of digital and analog ones, most decent digital pedals are awfully quiet EXCEPT reverbs. And you'd be surprised how many pedals like one power supply and not others.

For this exact reason I run any and all digital pedals in the amp’s loop, which really helps obviate the noise floor by increasing SNR. All analog out front - digital stuff in front is just too hissy!

What power supply are you using, that noise floor in my experience is usually due to the power supply.

Seems like the V2 was set to harmonic trem while the V1 was set to tube trem in the comparison.

Digital signal processing can suffer from manifold artifact noises caused by numerous timing references more timing references, echoes and artifact noises made my those timing references and some weird incompatibilities with the DAC/ADC other CODEC converters. The Spin chip has that weird tick after a reverberation. They all have some odd Nyquist & Shot hissing & rushing noises going on.

Why are you comparing the harmonic trem on the v2 with the tube trem on the v1?

This is why I use an effects loop pedal. That way I can choose between playing straight into the amp or running through the loop w/ the pedals. I typically don't use pedals though. If you use pedals all the time this probably doesn't make much sense.

Yeah that MXR reverb never made it to my board because of how noisy it was. Funny you show that pedal in this video. I have hearing issues and hiss like noises really makes it hard for me to hear the details i need to hear in my playing. Its a reason i stick with my setup ive had just about the same for over a decade. When i try newer pedals, a lot of them add this type of noise. So when i try new pedals out, before i even really try the effect itself out to try the effect, im making sure the pedal isnt noisy first. Kinda funny your testing the hiss level in these digital pedals before your actually trying the effect the pedal offers. In this day and age i dont get it. My board is all analog other than my TU-2 Boss Tuner. But that pedal doesnt add any hiss to my sound. But everything else on my board is noise free compared to some of these digital pedals and some of these pedals cost a pretty penny.

Clean power does wonders, some pedals are just noisy. I’ve learned to run digital pedals on a separate power supply from analog pedals.

What maketh me sad is that, as you have pointed out many times, certain amp makers have a design flaw/cost save that have continued for years upon years but they do nothing about it. And here we have a pedal design issue that could very likely be addressed. Would I pay a bit more for more silence? Yes. Period. Will the manufacturers listen? Um… Lyle, if only you ruled the world… ;))

I've noticed this! I have a terrible analogue pedal board with some awful wiring that I still have fix up, but it's as quiet as a mouse plugged into a valve amp, even at fairly loud volumes. But I was very keen to try the new Orange Terror Stamp pedal-amp, which sounds great, until I stop playing, and then emits this God awful digital noise racket! Unusable. Why is it so quiet plugged into, say, my Tiny Terror, but SO NOISY into a Stamp??

Were you using isolated power supply feeds for each pedal? If not the digital pedals inject their pulses onto the ground lines and they will never be quiet.

I thought this was normal and I never really cared, other band members didn't care either, the audience didn't care either - perhaps that may be a reason the manufacturers may not care to address this issue... fascinating topic though, I found the video interesting :)

I have the MXR M300 and dont have that issue, im using it with a Zuma and in stereo though

Boy they ARE noisy ,huh! The power adapter makes a difference but yeah. Kinda noisy. Although I DO only have a few crappy digital pedals other than my Keeley Vibrotrem which I LOVE. The rest are analog.Imma watch this!! 🙂

I have this problem but only when pedals are in the effects loop. Front of amp they are fine but it’s not where I want them. And it’s only some digital pedals. I’ll mention names: UAD and Strymon are ok. Walrus, Keeley and Eventide are not. How much of the responsibility goes to the amp maker and how much to the pedal maker? What is the incompatibility? I’d rather keep the pedals TBH and am at the point of switching amps. Advice?

Need a new delay; TC Flashback or Boss DD-8? Leaning towards DD-8...

Valid

I’v just returned the Fender Tre-Verb pedal for that same reason. Too noisy, even when not engaged…none of my other pedals do this. Very disappointed as the sounds themselves are cool, but the noise is still noticeable over the guitar…

I use a Boss noise gate. I can't stand noisy amps and pedals.... especially between songs, I've seen even Pro's have noisy amps. It wears on your ears and to me it seems kinda amatuer-ish.

i had one of those belle epochs and was shocked at the noise coming from it. even with a regulated PS the thing was so noisy

I had this problem with a 4 digital pedals on a board of 12 total. I got the Empress Buffer(input and output are buffered), which has a loop in and out, so I’m still running everything through the front of the amp. It’s made my amp nearly silent, even playing gigs at nearly 120db. One has to adjust the volume on everything to be right, but only a Uni Vibe and an Wah I have, that’s a tad scratchy(needs to be re-soldered), are the only pedals that cause any real noise. If I used a power supply like those Cioks ones, instead of the MXR Iso-Brick and a Pedal Power 2 Plus, it likely would be dead quiet, even at over 100 db. The only times I get noise that is loud enough to be distracting, it’s been a cable or a pedal that has a wiring issue. The guy from Vertex, has many videos on pedals that can work, or help, snd the buffers that he likes the best, as well as every step one can take to get the sound of the guitar into the amp, when all is bypassed, with long cable runs, and/or huge pedalboards, while having no noise issues. I use a 20 foot cable to the guitar input jack, a 15 foot cable out to the amp, with a pedalboard of usually 10-12 pedals. My amp sounds just like plugging straight in. Hope I helped. Really dig your videos.

You had the Flint v1 set to '63 tube in the Harmonic Tremolo comparison.. :) They sound extremely similar in fact!

what i don’t understand is why it’s called Flint??

also, when the switch sounds like gun going off....argh

My Strymon timeline is really noisy. All the sound guys notice this in my live shows.

I sort of dislike anything digital. (and yes, I am aware of the irony of decrying digital technology while using a computer). I like analogue things, where signals stay connected, and you can physically see where issues are and fix them when necessary. An example is my fairly expensive digital home stereo receiver/amp. For whatever reason, it often suddenly loses connection to my phone when streaming music, so I might have to play around with doing a reset on the amp, or restarting my phone, etc etc. Where back in the day, I physically plugged my tape deck or whatever into my amp, and it NEVER, EVER failed. Bah.

Not sure this is a fair comparison. On the on side you have an analog device with very little besides signal going on in the box. The only noise is the intrinsic transistor and op amp noise. On the other side, even in bypass, the processor is running along with any voltage regulation circuitry. Perhaps a better way to view it is that the digital pedals, if designed correctly, are as quiet as they are. The noise from clocks and other switching is far greater than that of a simple analog device. I don’t think it’s reasonable to expect any different. In a similar way a switching power supply will almost always be noisier than a linear one. Just the nature of the beast I think.

This video has unfortunately sent me down a rabbit hole. Three very expensive digital pedals at the end of my chain, everything else analog. Take the cable out of the amp, dead silent. Remove all digital pedals, almost just as quiet.

I recommend you use a simple looper pedal so both pedals sit nicely in their own loop instead of chained together with a cheap jumper cable. Another thing is that we have NO IDEA what kind of power supply or power supplies you are using. Have you tried Cioks or GigRig... or are you just running some wallwarts here? I think it would be good to know what kind of equipment there is being used besides taking your word for it.

As a 60 year old electronics noob, I have vaguely and apparently mistakenly thought analog equals tubes, and digital equals SS. Could you briefly clarify the difference between an analog pedal and a digital pedal? Im assuming a digital pedal has a processor of some sort, and the analog pedal does not. So how does the analog pedal process the signal? Thanks and cheers!

Interesting! I have an oposite experience. I had additional noises with analog pedals (noise gate, compressor, OD, dist, and fuzz in chain). No matter what power supply, isolated or not. But then I switched to Boss MS-3, where all those pedals are modeled, plus I add delay or reverb, and the chain is dead quiet. I compared to straight signal and I don't hear any difference.

My band uses 90% digital pedals and we've never had this problem. The only time we get unwanted noise is when the power fluctuates and the entire practice space powers down and back up in a split second.

Seriously! I sold my source audio pedal because it had a high pitched noise. I just got a zoom MS70 and It came back. I was thinking is this just me.

Life's too short for pedals.

I can barely notice noise when practicing with the flint. Playing live it’s not even a concern.

Cheap=hiss....but not always apparently. My Gibson guitar is quiet, regardless of volume. My noisy pedals are compressor and overdrive. Both cheap shit.

Ive stopped using valve amps. Too noisy..😎

Or you have INTENSITY, significantly decreased in the NEW ONE when testing "popping" noise!

If you like a pure, unadulterated sound, why the monster cable which rolls off all that top end? They’re dogshit.

I understand that the point of the video is show the high noise floor of some digital pedals, but comparing them to the Telos is apples to oranges. At around $500 US in todays money the Telos would be out of the range for most players. They would most likely settle for a Spark and a Klon clone from Amazon. These pedals are built to a margin price point. A slightly higher noise floor is obviously acceptable to them in order pack them full of the "features" that are going to sell it. None of the paid channels on YT are even going to consider a slightly raised noise floor in their reviews and the manufacturers know that.

Well you sort of come to the conclusion yourself, 'they pack a lot of stuff in here' it's mainly a layout and size problem, having design pedal for a major lable myself, getting the layout engineer to not flip his lid we had to do a lot of stuff differently then the prototypes I build, it's a lot of circuitry in a tiny space, shielding and physically isolation, digital and Analog circuits are not possible plus you need to conform to a form factor, I my designs I had caps that in a perfect world would sit just right next to the opamp, run through vias and halfway across the board, it's just the way the cookie crumbles.

My wife prefers the hiss than my playing. I dont blame her.