Build a NAM modeler you can gig with for peanuts - it's as easy as Pi

[nevershouldhavesoldit]

After your ringing non-endorsement of the Valeton, I'm favoring building a PiPedal to experience NAM, and picking up an Alto TS410 as both my PA and a FRFR guitar cab. I've been playing with single board computers since the Beaglebone came out, and I have a few Pis on the shelf. So I'll set one up later today and get started on the PiPedal. Stay tuned!

...and here it is! Pipedal is a modeling program created to run on a Raspberry Pi. The Pi is a computer the size of a deck of cards, and it's been around for several years. I've created everything from 8 channel audio front ends to multichannel DAWs that run decent recording software and work well on location. I built one into the processor for our condo building's video displays. They're fantastic, easy to set up and use, and amazingly powerful. I thought there'd be at least one modeler out there for the Pi, figuring that I'd write the code myself if I couldn't find one. Thankfully, PiPedal is already well developed and ready for us to use.

The bottom line is simple - it really works!! The latest version uses A2 NAM models that you can download free from tone3000 - and there are hundreds and hundreds of great ones available. There's no audible latency, and it's remarkably quiet even with no balanced lines or I/O. You need a DAI to provide both an input for the guitar and an output for audio. Every Pi has a headphone jack that should also be accessible for audio out, but I haven't tried that yet so don't hold me to it. I'm using my little TASCAM digital recorder for I&O right now while waiting for an inexpensive DAI to arrive so I can make up a self contained unit in a little travel case. This sucker is definitely gigworthy.

It was designed to be run on the latest version (RPi 5), but it will run OK on a 4b if you only use a few models in a chain (e.g. amp head, one or two effects, and a speaker IR). It can be controlled with a USB MIDI pedal in addition to the screen of your phone, tablet, or computer. There's dual band Wifi built into the Pi, and it acts as a hub. So you can connect your phone or tablet directly to it on a gig or use it over your home Wifi network for home playing, recording etc. Here's the control interface (which looks the same on phone, tablet, and computer):



I first set it up running into one of my recording monitor systems. That's a JBL 305, and it sounds fantastic as a moderate volume FRFR system for guitar. It'd be a great setup for solo dates and low volume trio work.



And here it is with what will be my gigging setup. Modeling requires FRFR electronics and speaker, and a Toob Metro FRFR II is the best thing around for this. The amp shown is my TC BQ500, because my BAM200 is already packed as backup for tonight's gig. Relax, Markku - I won't unleash the full power of the 500 on it The mic sitting on it is there for recording the clips below - my SM58s are also already packed for tonight.



I only had time right now to make 3 examples for you. That's a very cheap mic, so sound quality is not the greatest - but I think you'll hear the virtues of this concept and my little system even so. I used my Les Paul 7 for these, since I was changing the strings for tonight's gig. It has an EMG in it, which has no personality of its own. Here's the Fender 5e3 clean model:



Here's the 5e3 model with full on gain, al la early Carlton. There's obviously no reverb, but I discovered after recording it that there was a graphic EQ model in the chain with a bit of low end boost. I gotta tweak this one for the tone he got on his Steely Dan stuff:



The last clip is a big clean Fender with a Danelectro DJ-9 Surf 'n Turf pedal model. As soon as I heard the first note, I thought of Sleepwalk. So here it is, with slide on the first chorus and the rest picked. I'm particularly impressed with the pick sensitivity of some of these models. LIsten to how well it brings out finger vibrato in this one.



I'm very impressed with how good the models are, even through a single driver Toob. Since I need a PA for my new gigs and vocalist, I'm planning to get an Alto TS410. It makes more sense than selling my Blu 6 to buy a Bud 10, and it should be powerful enough for any gig I'll ever play. I've tried models of an old GIbson amp, a Twin, a 5150, a Dumble ODS, a Bassman 4x10, and several effects - and everything really does sound so close to the original that it's astounding. NAM modeling really works well, and it's fun. I probably won't gig with this much once I've wrung it out and learned to get the most from it. But it's a great way to experience a lot of cool and expensive stuff without having to find or buy it.

[WilliamScott]

Very cool but can't you just download NAM models into your phone with a NAM app? I like your Sleepwalk version.

[nevershouldhavesoldit]

Very cool but can't you just download NAM models into your phone with a NAM app?

There are programs you can put on your phone that will load NAM and IR files. But you have to use both an ADC and a DAC to accept your guitar's signal and to deliver the modeled output signal to an amplifier. So you also need a device with an input for your guitar and an output to your amplifier that will convert your guitar's output into an audio signal suitable for amplification and reproduction. There are embedded DAC chips in smartphones, but they don't offer the audio quality and flexibility of the Pi or a dedicated NAM based effects device. The audio noise floor, distortion levels, etc are much better even from a $125 Focusrite than they are from most smartphones. If you're going for the fidelity of an amp model, you really want the most accurate systems you can get.

NAM models also require significant processing power to render them accurately and without artifacts. Especially for live performance, it doesn't take much latency, noise, etc to ruin a gig. Our iPhones and better Androids do have serious power. But it's not at the level of the best NAM processors (yet).

NAM XT and GiGFast Lite are examples of such programs for phones. But you also need a digital audio interface like an iRig. For Apple devices, you also need OTG USB or an Apple camera adapter. I've never done this on Android devices, but the principle is the same. Using a phone is more than a little complex, and I wouldn't want to bother with it on a gig. A simple pedal is the easiest way to go, but the better ones are rather costly right now. The simple ones use a 3 process version of NAM files (A2 Lite) that's not as accurate as the 8 process system used in the better ones.

[Spook410]

Thanks for taking the time to write this up. I've been spending time with my new Valeton GP-5. Crazy what you can get for cheap. It does the NAM A1 to Snaptone (Valetone proprietary) format. I'm not sure what differences I'll see when I can run NAM A2 Lite natively. So far my experience has been just OK but we're still at first steps.

I am a little disappointed in the free NAM capture library. While I have found a nice Super Reverb and a couple DeLuxe's, the library does not consider clean tones as much as I would want. And I thought there would be more boutique and vintage. Over time I suppose. In the meantime I am learning new things and enjoying the process.

[GuyBoden]

Excellent

[Spook410]

The Valeton GP-5 and free NAM files are becoming something of a surprise. Started as a simple experiment. New tech and all. And it continues to be that. However, it's already better than my main rig. A board with a Joyo American through an IR Cab Modeler. It's also better than my Roland Artist combo amp. Not by a vast amount in either case but certainly better. For now it appears this will be my primary on a small board with a proper looper and peterson tuner. Don't think that's long term. The inexpensive multi-fx market is rapidly evolving and within a few months I'll be able to get something with better outputs and overall features in the sub $500 range which is fine. But.. jeez.. this thing cost me $64 and it didn't take much to get several very good tones.

[sgosnell]

I may give this a try. I have an ex-chromebox lying around, with Debian installed on it. It used to be my home server, but I had a more capable NUC on hand that replaced it. I don't really need this, but it might be fun to play with it.

Good lord, it wants to install 137 dependencies. I downloaded pipedal and started the install on my home server, but I don't want to put that much cruft on it. I'll look into using the old chromebox, long since converted to Linux.

[nevershouldhavesoldit]

I may give this a try. I have an ex-chromebox lying around, with Debian installed on it. It used to be my home server, but I had a more capable NUC on hand that replaced it. I don't really need this, but it might be fun to play with it.

That’s supposed to work, although I haven’t tried it with a C’box. I converted one of the originals to Ubuntu years ago and Pipedal is supported for Ubuntu 24 and up, according to the website.

The limiting factor is processing power, so it depends on the CPU in your ‘box. Mine is a second gen with a 1.3 Celeron, which is probably not enough. PP doesn’t need much RAM, but it pushes my overclocked Pi 4b with SSD to its limits. I can give it a try when I have an hour to play with it.

[sgosnell]

I farted around with it today. I got pipedal installed, sort of configured, but I still haven't got around to actually trying to run anything. It has a Celeron 2955U CPU and 4GB RAM. The only reason I no longer use it as a file server is that the network speed isn't great, and my NUC is much faster in all areas. I'm sure it would do the job, but having a capable server is more important to me than playing with a semi-pedal. The SBUS and Toob sound good enough for my needs, and this is merely an academic exercise. It turned out the pipedal installation pulled in over 300 dependencies, which is perhaps the most I've ever had for just a package. An entire desktop environment such as gnome might install more, but not much. I'm not highly impressed yet.

[Spook410]

.., and this is merely an academic exercise. It turned out the pipedal installation pulled in over 300 dependencies

Thinking that those who pursue the most academic exercises over time end up with the better neural connectivity later on.

[GuyBoden]

This is great stuff and a very worth while endeavour. I was tempted to create a dedicated device with my ElectroSmith Daisy Seed board, but the Daisy Seed has processing limits, so can only process NAM lite.

But, you could just buy the Valeton GP-5 NAM file pedal for £60.

[Cunamara]

Yes, for most of us something like the Valeton would be the easiest solution; but if you have a Raspberry Pi lounging about and enjoy that sort of tinkering, it could be worth a try- and it is easily repurposed. I am unclear as to how Dave gets his guitar signal in and out of the Raspberry Pi. There are some hardware connectivity considerations, especially if it is going to be used in live performance.

[sgosnell]

With a Pi, like most any other computer, input and output is generally via USB, although some computers have other input and output devices. I have a couple of cheap USB DAC devices lying around, one of which is switchable from DAC to ADC, or between in and out. I plan to use one for input, and one for output. As for getting the guitar signal into RCA jacks, there are various adapters that can do that. I think I'll probably go from the guitar to the Boss GE-7 first, to get a buffered line-level signal. I'm not in a huge hurry, and other things have been taking my time lately, and will for several more days. Grandchildren always take priority over yet another method of producing noise.

[nevershouldhavesoldit]

I plan to use one for input, and one for output.

That won’t work with PiPedal. It doesn’t recognize separate DAIs or I/O converters - the details are in the documentation. It also doesn’t recognize every DAI. My TASCAM DR40x works great, but it doesn’t see my M-audio 2x2. At first, I thought it was because the M is several years old. But it’s still in production, still USB-C, and still the same 96/128 resolution. They added a second XLR input and MIDI, but it’s otherwise the same. I have no idea why it won’t work with PiPedal, since it works great with every other computer I have.

Check the PiPedal webpages for the list of known compatible DAIs. I’m using the headphone out jack on the TASCAM to drive the amplifier, because I don’t have a DAI with better quality audio output and a 1/4” jack. To get the best sound from it through a decent powered cab, a better DAI with a balanced XLR output is best.

[sgosnell]

A quick scan of the docs seemed to indicate that an external i/o might be necessary, but perhaps I misread it. The former chromebox has headphone out, as well as microphone in, so maybe those will work. I've tried nothing yet.

[nevershouldhavesoldit]

A quick scan of the docs seemed to indicate that an external i/o might be necessary, but perhaps I misread it. The former chromebox has headphone out, as well as microphone in, so maybe those will work. I've tried nothing yet.

You are correct. You do need an external I/O device. You could probably force the mic input and headphone output to work with a little command line alchemy to get them recognized by PiPedal. But the electronics on those analog routes are noisy, low quality, and possessed of demonic latency. You need a USB DAI for best results, and the same device must be used for I and O (again primarily to miminize latency).

Ideally, you want a 24 bit DAI with a 96 kHz or better sample rate. The main requirement here is wide dynamic range. A 16 bit system is limited to 96 dB, while a 24 bit system can achieve as high as 110 dB. The 192 spec is not as important, and you won't hear much (if any) degradation even at 44.1 kHz. But you will definitely hear a difference in the quality of modeling with a simple Scarlett or similar $100+ device comapared to a $50 Behringer.

[sgosnell]

Well, I'm not willing to spend any money on this project. If what I already have on hand won't work, then I'll abandon it.