Analyzing Joost Assink’s SRV Little Wing Patch

This is a brief analysis of the Ultimate Fender John Mayer Clean patch created by Joost Assink (JazzInc) and posted in the Line 6 Helix forum. I’d like to thank Joost for posting this patch and the included speaker impulse responses, and giving us the opportunity to analyze an interesting and different patch. Hopefully he’ll correct any mistakes I made in reconstructing the patch design and any of the included details.

There are three signal paths, two for parallel guitar amps and one for stereo playback through Return 1/2.

Path 1: Guitar with clean amp, delay and chorus

Path 1 starts with multi-input for guitar directly into a volume Pedal block. In this case, the volume pedal controls the drive into the amplifiers and can be pulled back just a little to eliminate the small amount of breakup you hear at full volume (especially with double coil pickups).

The Looper is next in the signal path meaning the raw guitar (after the volume control) is what is recorded in the loop. When overdubbing and playing along with the loop, all overdubs and the live guitar are going into the same amp and effects. Putting the looper at the end of the signal chain allows you to have different effects in different loop overdubs. In this configuration, its important to keep the amp pretty clean as any distortion created by the louder signal, either the loop or guitar, will tend to “duck” the other when the amp distorts. Note that the Looper is stereo, but should probably be mono since it is followed by mono blocks. This will increase the potential length of the loops.

There is a split following the looper to create two parallel paths, 1A and 1B. Path 1A has the Transistor Tape delay while Path 1B has 70s Chorus. Using this parallel path separates the delay and chorus so that the delay repeats are not modulated and retain their clarity.

The 1A and 1B paths come back together into the US Double Nrm amp model, the Normal channel of a Fender Twin Reverb. This is a pretty low gain amplifier and that helps keep it clean. The power amp is set to be as clean as possible, with Master on 10 to minimize preamp distortion from the Drive control. The Bias is set high and Bias X set low to make the amp even cleaner. Sag is set low to maintain articulation and tight response. Drive is set so the amp just barely starts to breakup when the guitar is played hard.

The ’63 Spring Reverb is chosen and placed between the amp and the speaker to better simulate the Fender Twin Reverb. Since the reverb is going into the speaker IR model, the brightness of the springs will be tamed by the speaker. This isn’t exactly the same as a Twin Reverb since the reverb unit is after, not before the power amp. However, this won’t make that much difference if the amp is mostly run clean. A Hall reverb would likely sound better after the speaker, to better simulate the speaker in a room.

Next is an Impulse Response block containing a speaker IR. I’m guessing what’s in the IR based on its name, and the file names in the Redwirez IRs. It looks like a G12M with a U67 condenser mic at CapEdge set at 50% blended with a Weber-Blue 12 with a Royer R121 ribbon mic at Cap set at 50%. This will be a pretty warm sounding speaker. Joost likes to close-mic the speakers, so these might be set at 0″.

The speaker is followed by a Studio Tube Pre Preamp set to be transparent. This is likely acting somewhat as a limiter using the Drive control to add some distortion to clip off the overly bright clean peaks.

The last thing in the signal chain is the LA Studio Comp compressor. I’m not sure exactly how the compressor is being used. The peak reduction is set to 0, so the compressor should not be applying any compression. The Mix is set to 54% meaning the compressor is being run essentially in parallel with the dry signal. This would provide some sustain as the compressor releases, by preserve pick attack which can get chopped of by a fast attack time, which the LA-2A has. I’m guessing the compressor is playing a similar role to the tube preamp, it just tames some of the harsh peaks that can come from a very clean guitar amp played loudly, but do it without adding any distortion.

Path 2: Guitar with slightly dirtier amp and distortion pedal

Path 2 receives the same multi-input and also starts with a Volume Pedal block. This block, and the one in Path 1 are both controlled by EXP Pedal 2 so that both amps are controlled together. Again, the volume pedal block is in front of the amp so it controls amp drive, similar to the volume control on a guitar, but without the high end loss from cable capacitance.

Next is a distortion block using the Scream 808 model, set reasonably hot and bright. Turning this pedal on provides distortion, but only in Path 2. Path 1 still has the clean sound, blending the clean and distorted sounds together. The Tube Screamer this model is based on also blends direct signal with the distorted signal, but this configuration provides greater control of the blending. Blending distorted and clean tones together can give the best of both. The distortion adds sustain and rich harmonics while the clean tone provides solid pick attack, articulationn and chord clarity.

The amp model in Path 2 is a US Deluxe Vib which will break up sooner than the US Double Nrm in Path 1. The amount of breakup is reduced a little by turning down the Master a little, and setting the Bias all the way up and Bias X all the way down. I’m not sure, but I think the US Deluxe Vib model has the bright switch on while the Nrm models don’t.

Again in Path 2 the reverb is between the amp and the cabinet IR. In this case a Plate reverb is used to provide a warmer, or different color reverb.

Next is the Impulse Response block for the speaker. Again I’m guessing, but it looks like a G12M with a U67 condenser mic set at 50% blended with a Weber-Blue 12 with a Royer R121 ribbon mic set at 40% followed by an EQ high-pass filter at 50 Hz and set at 40%. This will also be a pretty warm sounding speaker, but a little brighter than the other IR in Path 1.

A footswitch is configured for a minimum at 80 Hz and a maximum at 160 Hz. The same footswitch controls a 75 Hz and 180 Hz Low Cut on the IR in Path 1. These are probably to remove mud from the distorted tone. I prefer to use an EQ block to place the low cut before the distortion so that the low frequencies don’t create a lot of intermodulation artifacts with the mids. This clean up the mud and also makes the distortion smoother and sweeter. Both IRs also have High Cut set to 8 kHz to remove any fizz from the distortion without having much impact on the clean tone.

Path 2 has the same Studio Tube Pre block and LA Studio Comp after the speaker IR. The compressor has a small amount of peak reduction, and the Mix is set to 100% so there is no blending with the dry signal. This is likely to complement the compression in Path 1 and reflects the different role the amplifier plays in this path.

Combined Amps

Both amps are mono and centered on the output so that their tones are blended into a single cohesive whole. This is important since the effects in each amp are quite different. This is a great example of using different amplifier and effects for different purposes, and blending them together to combine the effects. This makes it easy to optimize each path for its intended purpose or contribution, then to blend them together, using their output volumes and panning to control the mix. This is an interesting patch that can help us learn more about how to use the Helix. Thanks Joost for the excellent contribution.

Here’s some final thoughts from Joost:

  • There is also a mid boost, which simulates the mid-cap bypasses you see on such amps. Can be handy for cutting through a dense mix.
  • The 35 impulse response adds some room sound and indeed is a little brighter on the darker amp
  • The LA2As just add a little something even when they’re not compressing, and they do take the edge off. Same goes for the tube preamp. Basically, I do what I would to in the studio: get some great speakers, great mics, a good preamp and a good compressor to capture the sound of the chain before it. I also really like the Emphasis control on the LA2A to tweak response. (same goes for the power amp characteristics on both amps to tweak feel and response.)
  • The double amp setup gives a lot of options. For instance, the treble on the Twin is a bit too much for me, so I like to tone that down and bring in the thicker, sweeter treble on the DeLuxe. Vice Versa for the Presence. For different applications these two amps can also be used to their strengths together.
  • I really feel you need very good IRs to get the best out of the Helix.
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Creating a Helix Electric Guitar Patch (updated)


The new Line 6 Helix amp modeler is an awesome device, capable of creating a wide range of really great tones for acoustic guitar, electric guitar, bass and vocals. However, it can be quite a challenge figuring out how to put all this capability to work for your particular needs. The factory presets are a good place to start, auditioning each one to get some ideas. But these factory presets are generally designed to demonstrate the device’s capabilities, and can be a bit over hyped and impractical for gig use.

In this post I’ll describe some different approaches to setting up electric guitar patches in Helix. Then I’ll go into some detail on my goto electric guitar parch, covering the reasoning behind what is placed where in the signal chain, and how each effect block is configured. Of course the tone that works for my playing style, guitar and FRFR amp may not be even close to what you are looking for. But the thought process might be useful in helping you come up with your own tone.

I decided to incorporate some of the things I learned Analyzing Joost Assink’s SRV Little Wing Patch into my Electric Guitar patch. This updated version makes the following changes:

  1. Use a Studio Tube Pre instead of a Low and High Cut EQ for controlling drive and as a mid-focus EQ. This not only provides a warmer tone, but adds the flexibility of getting some distortion from the Studio Tube Pre that isn’t possible with the Low and High Cut EQ.
  2. Moves the Amp and Impulse Response blocks to path 1B so that most of the mono blocks are in Path 1, and to make room for more stereo effects in Path 2.
  3. Added another Studio Tube Pre after the Amp and (speaker) Impulse Response blocks to warm the tone a bit.
  4. Added the LA Studio Comp at the end of the chain, just before the Looper to further warm the tone and add a tiny bit of compression on the final result.

Approaches to Patch Design

Most guitar players use a number of different guitars, pickup combinations, tones and effects in different songs or even in different parts of the same song. This adds interest and color to you playing that helps maintain the audience’s attention. You can do a lot with just the right pickup selection, and using the guitar volume and tone controls. But Helix gives a wealth of other choices for distortion levels, effects, amp models, and synth effects. How do we setup patches to organize all these capabilities so they are ready and easy to use in a live setting?

There are two broad approaches to designing patches: Stomp mode: get the most out of each patch, or Preset Mode: make each patch for a specific purpose. These two approaches correspond to the Helix Stomp Footswitch Mode and Preset Footswitch Mode respectively. In stomp footswitch mode the footswitches are used to control 8 or 10 (Stomp Mode Switches global setting) effect settings while in preset footswitch mode the footswitches are used to select between 8 different patches. The Preset Mode Switches global setting can be used to provide a combination of both with one row of stomp switches and another row of four presets.

Stomp Mode

Stomp mode minimizes the number of patches and reduces patch switching within and between songs. The idea is to design the patch to reflect your playing style and the range of tones you need. Then you use just one patch, getting different tones by turning effects blocks on and off within the patch. This is very similar to how you would setup a typical guitar amp and pedal board. You might have two speaker cabinets or two amps to get a range of tones, but that’s it. You would typically have one pedalboard that contains all your effects in a fixed order. Then you change tones primarily through bypassing or turning on effects in the pedalboard.

Helix can be used this way too. But there are some challenges to address:

  1. Although each main path has its own independent DSP, and can contain up to 16 blocks (not counting inputs, outputs, splits or merge blocks), its still pretty easy to run out of DSP in one of the main paths.
  2. There are at most only 10 stomp footswitches available within a patch. If you have more than 10 effect blocks in the patch, you’ll need some external MIDI controller to control bypass on some of the blocks
  3. Mono blocks sum their stereo inputs. So any stereo effect block before a mono block is lost.
  4. Helix doesn’t currently support scenes within a patch to support reusable configurations or to switch models within a patch

Use stomp mode if you have a signature tone that just uses different distortion levels and a fixed set of effects. Don’t use stomp mode if you’re playing a wide range of styles in a cover band, it will be too hard to make one patch do everything.

Preset Mode

Preset mode minimizes the number of blocks in each patch, and uses different patches to create different tones. Each patch is designed for a specific purpose either for a section within a song, or for different songs. Patches are often ordered in setlist and banks to allow fast switching from one tone to another. Once a patch has been selected, the Mode switch (FS12) can be used to temporarily switch to stomp footswitch mode to control the blocks within the patch. In this case you’re much less likely to run out of footswitches to control the blocks since the patch is designed for a specific purpose. You can also use the Preset Mode Switches global setting to have a row of four stomp switches and a row of four patches. This may be very convenient for Preset Mode since you can quickly switch between four presets in a bank for different sections of a song, control up to four effects blocks within the patch, and use the bank switches to select the next song in the setlist.

Like stomp mode, preset mode also has some challenges to address:

  1. It takes some time to switch patches, this has to be done carefully within a song
  2. Helix doesn’t support effects trails between patches, so synth, reverb, delay, and other effects might be cutoff abruptly depending on when you switch the patch

Use preset mode if you are playing in a cover band and have to reproduce very different guitar tones, possibly with a Variax, need to switch patches within or between songs, don’t need too many effects in each patch, and can deal with the patch switching delay.

The rest of this post explores a patch built using the stomp mode. This works well for me because I play three different instruments in our band: mandolin, acoustic guitar and electric guitar. I use a patch for each instrument and only change patches when changing instruments. Helix is great for this because of the I/O flexibility – I can leave all three instruments plugged in at the same time with only one instrument active in each patch.

Signal Path

Although there are no rules for establishing the order of amp and effect blocks in your signal chain, there are some guidelines that work well in practice. Here’s a few best practices that may be useful in guiding your tone setup:

  • The larger the room, and the louder you play, the less effects, especially reverb or delay you need.
  • Use delay instead of reverb for ambience, especially in a larger room, to avoid washing out the tone and to fit better in the overall mix.
  • Simple ambience can be achieved with a slap-back delay of 125 ms with no repeats. Blend to taste. This can often be left on all the time.
  • Smooth out the guitar sound, and blend into the mix better using 500 ms delay with a couple of repeats. Especially useful in a three-piece situation.
  • Most guitar players play in mono – but that’s changing with digital amplifiers. Before the amp effects are almost always in mono while after the amp effects (often in the recorded track) are usually stereo.
  • Overdrive, reverb and delay are timeless while chorus has an 80’s feel. Use sparingly and with caution.
  • Minimize cable length and use low-capaticence cables to get the most out of your guitar.
  • Use the minimum number of effects in the signal path that you need at any point in time to avoid killing tone.
  • Use the minimum amount of distortion needed for the song. Too much just washes out the guitar and has no articulation.
  • Use EQ before distortion to cut bass to reduce mud, and another EQ after distortion to cut treble to reduce ice-pick. Increase bass and treble cut with increased distortion.

A typical effect chain starts with tone shaping effects and ends with ambience effects.

Static Tone Shaping: Tone shaping comes first, including guitar tone, volume and pickup selection. This is followed by compression to control pick attack and sustain.

Dynamic Tone Shaping: Next comes variable tone shaping devices like Wah Wah, phase shifter, or Uni-vibe, possibly Flanger too. These are modulation devices, but modulate phase or tone more than frequency, and therefore can go in front of distortion. Of course in the old days, all effects were at the front of the amp, so we’re use to hearing them this way too.

Distortion and Overdrive: Overdrive, gain staged for different boost/distortion and voicing levels. One should be for controlling metal lead distortion, and another for creating the overall amp sound. The second should clean up well when turning down the guitar volume. This section can also be handled completely by the amp if it has sufficient gain staging options. Using overdrive pedals however can give more control over the amount of distortion and overdrive, as well as the tone shaping or voicing. Use a gain boost and/or EQ before distortion to control the distortion tone. Use a gain boost and/or EQ after distortion into a clean amp to do a simple volume boost for clean or distorted tones.

Amplifier: The guitar amplifier would typically come next, and usually includes the speaker cabinet and mic. This allows all the modulation and ambient effects to be “in the air” and not overly impacted by the amp itself.

Modulation Effects: Mod effects like flanger and chorus come next. These effects modulate frequency and usually work best after distortion. More classic tones came from pedals before the amp which provided most of the overdrive. This can result in a less articulate tone, and reduces the impact of the effect. In some cases, these effects were produced in the studio after the recording, especially flanger for a more pronounced effect that is operating on the distorted signal rather than being distorted by the overdrive.

Flanger might go before or after distortion depending on how pronounced the effect should be. Chorus would generally be after distortion in order to simulate doubling or Leslie effects.

Ambient effects: Delay and reverb effects go last. Usually Delay comes before reverb. Use a slap-back delay for clean ambience, and a longer delay with repeats to smooth out the overall tone.

Assigning Footswitches

Its a good idea if you are using multiple patches to organize the stomp footswitches as consistently as possible between patches. This makes it easier for you to remember where each effect footswitch is located. Helix has the scribble strips, which certainly help identify what a footswitch does. But you don’t want to have to look down at the pedalboard to find an effect switch in a live situation. Here’s a few guidelines:

  1. Put the footswitches in signal chain order from right to left. This corresponds to how many people organize their analog pedalboards, with the Wah at the far right.
  2. Use consistent footswitch assignments between patches to make it easy to find the right footswitch
  3. Name the footswitches with generic effect names, not the specific default Helix effect model names. Again this is to provide consistency between patches and make it easier to recognize the effect from the scribble script
  4. Put effects you change most often in the lower row, they’re easier to get to in a live situation
  5. If you use the Looper, put it on FS7 so its right next to the Record/Overdub footswitch after you switch to Looper mode.

Here’s my typical footswitch layout:


I use this same layout for mandolin and acoustic guitar, although the Overdrive and Distortion effects are very different.

Electric Guitar Patch

With the preliminaries finally out of the way, we can now get down to the actual patch details. This is my goto electric guitar patch. It designed primarily for Americana, Blues and lighter Rock styles, and using a Stratocaster (or single coil pickups). Its based on a Fender style amplifier, but takes liberties with the speaker model to get the desired warmth.


Path 1

Because of dynamic DSP limitations, and the number of effects in this patch, I have put the “before the amp effects”  and amp on Path 1 and the “after the amp effects” on Path 2. The output of Path 1A is sent to Path 2A which has no other input. The output of Path 2A is the Multi output, so the 1/4″, XLR, Digital, and USB 1/2 outputs are all active simultaneously.

In this configuration, Path 1 has most of the mono blocks including before the amp effects, the amp and the speaker IR block. Path 2A is mono for Studio Tube Pre, then stereo after that. This balances the DSP load between path 1 and 2, and provides extra DSP room on Path 2 for other expensive stereo effects like the 122 Rotary or 3 OSC Synth. The only issue is that there aren’t enough footswitches to control all the effect blocks in this patch. As far as I can tell, Patch Edit Mode, and MIDI CC messages do not currently support block bypass. I have raised this issue with Line 6. If Bypass was available as a mappable parameter, then you could use Patch Edit Mode to control seldom used blocks that aren’t assigned to a footswitch.

Guitar In

For this patch I have the Noise Gate on the input turned off since I generally use the patch with blues or clean tones. But its probably a good idea to leave the Noise Gate on with a minimum threshold in order to eliminate noise while still retaining the subtle dynamics of your guitar.

Wah: Fassel

The first effect in the signal chain is the Fassel Wah. Of all the Wah Wah pedals in Helix, this one sounds the most musical to me. I liked it in the HD500X too. Its before the compressor to deal with any odd peaks when using the Wah with a clean tone.

  • FcLow: 455 Hx
  • FcHigh: 2.2 kHz
  • Mix 100%
  • Level: 0.0dB
  • Controller: EXP Pedal 1
  • Footswitch: EXP Toe

Dynamics: Deluxe Comp

I like this compressor because it gives a lot of control that can be used to reproduce other compressors as needed. The compressor is mostly used on very clean tones just to even out the guitar dynamics a bit, and make clean tones stand out a bit more for solos. It’s placed before any EQ or distortion effects in the signal chain so it sees the dynamics of the guitar itself, not the output of most effect blocks. The compression ratio is set very high, which seems to work well on electric guitar. The Level is set for makeup gain and a tiny boost for clean leads.

  • Threshold: -40.0dB
  • Ratio: 6:1
  • Attack: 38 ms
  • Release: 200 ms
  • Mix: 100%
  • Level: +7.0dB
  • Knee: +6.0dB

Preamp: Studio Tube Pre

The Studio Tube Pre is designed to come before any distortion to provide low cut to control bass mud and high cut to control treble ice-pick. This block is tied to the Drive footswitch (along with the Amp Drive control).

The Studio Tube Pre sounds good and is a flexible means of adding some early distortion through its Drive control, and a mid-focus EQ using a combination of the Low Cut and High Cut parameters. By adjusting these two parameters, you can control the width of the mid-focus EQ and where it is positioned in the frequency spectrum.

In this case the high cut is kept pretty high because the block doesn’t add that much distortion and I want to preserve the guitar high frequency response then the amp is just breaking up. There’s just enough high cut to keep the drive-level distortion from getting fizzy. See the Amp block for more details.

  • Drive: 7.5
  • Polarity: Normal
  • Low Cut: 120 Hz
  • High Cut: 7.8 kHz
  • Level: 4.9dB
  • Sensitivity: Line

Distortion: Valve Driver

Before going into the details of this block, we have to consider gain staging. Since this patch is based on patch mode, and we want to get a wide range of tones out of the same patch, we use gain staging to control different levels of distortion. I like to have four gain levels in a patch like this one: Clean, Drive, Overdrive, and Distortion. Each of these gain levels increases distortion and uses various tone controls to control the distortion voicing.

  1. Clean: the amp master volume is set at 10.0 (all the way up) so that any initial distortion comes from the power amp section, not the preamp. For the Clean tone, the Amp Drive control is set just below any noticeable distortion
  2. Drive: this adds enough Amp Drive to just get the amp clipping. Its for typical Blues tones where the distortion is coming from the power amp and the sound is warm, full, expressive, and reacts dynamically to how hard you pick. Clean and Drive are controlled by the Drive footswitch where the Amp Drive switches from 4.2 to 6.0. Recall that when the drive is at 6.0, the Low Cut is increased to 160 Hz to reduce the bass going into the distorted amps. Fender amps really seem to need this base cut. Without it, the distortion gets muddy and a little nasty sounding.
  3. Overdrive: This adds the next level of distortion, usually for heavy blues leads. A distortion model is used for this additional distortion in order to control the voicing. Some treble cut will be needed at this distortion level to keep the tone aggressive, but still reasonably warm.
  4. Distortion: This is the most distorted tone in the patch and is used for heavier, closer to Metal leads. Again it uses a distortion model to control the distortion voicing.
  5. Insane: You can also combine any of the three Drive, Overdrive and Distortion tones to get increase distortion with different voicings. This is a lot of flexibility from three footswitches and one amp.

Some amp models (e.g., Soldano SLO-100 or the Solo Lead model) have clean, crunch and overdrive channels that support gain staging, distortion levels and voicings. However, these channels can’t be changed within a patch (no scenes in Helix). Using the distortion models gives more control of both the distortion and the voicing, so that works best when using patch mode.

Valve Driver is used to create the Overdrive tone, and is controlled by the Overdrive footswitch. Gain is set to provide additional distortion for blues leads while Bass and Treble are used to provide additional bass and treble cuts for higher gain distortion voicing.

  • Gain: 3.4
  • Bass: 5.5
  • Treble: 2.2
  • Level: 5.5

Distortion: Compulsive Drive

The Compulsive Drive distortion model is used to create the Distortion tone, and is controlled by the Distortion footswitch. Compulsive Drive is based on the Fulltone OCD. This is a very nice, and very flexible boutique distortion pedal that is a real Helix gem. This patch uses Compulsive Drive to get a nice creamy distortion that just sings. Combine it with the Drive footswitch to increase amp drive and low cut to get a bit more distortion with a slightly different voicing.

  • Gain: 3.1
  • Tone: 3.4
  • Peak Type: High
  • Version: V4
  • Level: 6

Scream 808 (Ibanez TS808 Sube Screamer), and Vermin Dist (Pro Co RAT) are also very good choices for this block. These have different distortion characteristics, and voicings.

Modulation: Script Mod Phase

Next in the signal path are modulation effects that change tone or phase of the signal. These can be placed before or after distortion. Their effect is a bit more pronounced after distortion, so I’ve placed them here, between the distortion pedals and the distortion created by the amp. That’s a compromise that attempts to get the benefits of both approaches. I keep the rate slow and the mix down to keep the phasor effect subtle. This make the effect usable in a wider range of situations.

  • Rate: 1.9
  • Mix: 39%
  • Level +1.0dB

Modulation: Ubiquitous Vibe

I use to own a UniVibe and loved the effect. Previous models in earlier Line 6 products weren’t that great, but the Helix Ubiquitous Vibe model seem dead on. This is just one of those effects you might need sometimes, especially for Hendrix tones. Its also useful when you want some tone modulation, but chorus is too much. The rate is controlled by EXP Pedal 2 with the min and max values set to mimic the typical speeds of a Leslie speaker. Lamp bias controls how the effect ramps up and down.

  • Rate: 0.7 – 7.6 (Controlled by EXP Pedal 2)
  • Intensity: 6
  • Mode: Chorus
  • Lamp Bias: 2.7
  • Mix: 50%
  • Level: 0.0dB

Distortion: Tycoctavia Fuzz

This is the odd effect that you might need for Hendrix tones. I don’t currently have this assigned to a footswitch, so it has to be controlled by selecting the block and pressing the Bypass switch. See for a great demonstration of a UniVibe and Octavia. You might also be interested in his Guitar Effects Survival Guide course. I found it very useful.

  • Fuzz: 7.5
  • Level: 6.7

Amp: US Deluxe Vib

I’ve been using Fender amps for many years and at one time owned a Deluxe Reverb. I should never have sold it, but there you go. This amp model has the bright switch on, and has a little extra gain compared to the normal channel of the same amp. It breaks up well at that critical junction where the power amp is just starting to clip.

There are a lot of choices on how to configure an amp and speaker model:

  1. Amp+Cab: automatically loads the matching cabinet for an amp, but allows the cabinet to be change. The lowest DSP load for an amp and a cabinet.
  2. Separate Amp and Cab models: allows the placement of effects between the power amp and cabinet, supports two cabinets in stereo. Uses more DSP.
  3. Amp and IR: lets you choose other cabinet models. Those from Redwirex, OwnHammer and Rosen Digital are very good and there are a lot of free cabinet IRs on the Web.
  4. Preamp: useful for input directly into a power amp connected to a guitar speaker cabinet

In this patch, I use the Amp model and no Cab model because I’m going to use an IR block for the speaker model.

The Amp Master volume is almost all the way up so that any initial distortion is created by the power amp, not the preamp stages. The Amp Drive control is controlled by the Drive footswitch to, along with the Studio Tube Pre early in the signal chain, support the Clean and Drive gain stages as described above. Recall that the Drive footswitch also controls the Studio Tube Pre to add some additional distortion and increase the bass cut when the Drive is increased. The tone controls are set for the desired clean tone using the Strat neck pickup. That often results in the bridge pickup being a bit too bright, but turning the guitar tone control down just a little fixes that and provides the overall clean tone. Distortion tone voicings are controlled by the distortion model controls and are set to sound good into this clean tone setting. These tones are pretty warm to suit my band’s particular needs. You might want to brighten them up a little. I raise the bias and lower the Bias X to provide a good clean tone. Reduce Sag to get a tighter tone.

  • Drive: 5.0 (Drive footswitch off), 6.0 (Drive on)
  • Bass: 4.7
  • Mid: 6.8
  • Treble: 5.3
  • Presence: 2.1
  • Ch Vol: 7.2
  • Master: 9.0
  • Sag: 4.0
  • Hum: 5.0
  • Ripple: 5.0
  • Bias: 8.3
  • Bias X: 3.2

Impulse Response

In an electric guitar setup, the things that touch the air often have a major impact on the overall tone. That starts with the guitar (including pick, strings, and pickups) and ends with the speaker cabinet. Helix provides a lot of cabinet options, including dual cabinet modes. But there are also a wealth of guitar speaker cabinet impulse responses (IRs) on the market and free on the Web that also sound wonderful. Support for IR blocks is one of the distinguishing features of Helix over the POD HD500X. Selecting the right cabinet (open or closed back), speaker, mic and mic position can really taylor the sound.

After trying a lot of Helix Cab models, and a number of my own Redwirez and Rosen Digital IRs, I finally settled on JOOSTALNICO-G12M-R121-U67 IR.wav from the Helix forum post My Two Rock/Fender clean tone, PRESET+IR by JazzInc. This is a very warm, low-end heavy model that uses a blend of two Redwirez models:

  • Basketweave G12M25s, with a Neumann U67 mic 0″ from the CapEdge
  • Celestion-blue 12, with a Royer R121 ribbon mic 0″ from the Cap

The warmth comes from the proximity effect of the close mic positions, the use of a ribbon mic, and the U67 which has extended low end. This combination of speakers and mics is still crisp and smooth. Distortion tones are thick because of the bass response of the speakers, but not muddy because of the bass cut before distortion. Those two speakers also provide a warm distorted tone since they aren’t overly bright.

  • IR Select: 33 (or the index were you loaded that IR)
  • Low Cut: off (the low cut is already included in the IR)
  • High Cut: off
  • Mix: 100%
  • Level: -18.0dB

Note that IR blocks are not stored with the patch, only the index to the IR block is stored. If you have the IR block loaded at a different index, then you’ll need to change the IR Select to the index where you loaded the JOOSTALNICO-G12M-R121-U67 IR.

Path 2

Path 2A has another Studio Tube Pre followed by all the after the amp stereo effects.

Preamp: Studio Tube Pre

This Studio Tube Pre is designed to come after the amp to warm the tone and provide after the amp low and high cut filters as needed. The effect is subtle, but does seem to improve the overall tone of the patch.

The Studio Tube Pre is set pretty flat and clean so that it does not produce any additional distortion. The low cut is set to minimize any sub harmonics created by the amp, while the high cut is used to control fizz and ice-pick from the gain stages and amp distortion.

  • Drive: 4.5
  • Polarity: Normal
  • Low Cut: 60 Hz
  • High Cut: 12.0 kHz
  • Level: 7.7dB
  • Sensitivity: Line

Modulation: 60s Bias Trem

All the effects from here on to the output are stereo. The effect order is modulation, delay and then reverb. Tremelo is a nice vintage effect, and one that’s included in the old Fender amps. So I included it this patch and assigned it to the Tremelo footswitch. The settings use a moderate intensity so that the signal doesn’t pulse too much. Spread is set to provide a small amount of ping-pong effect into stereo speakers. Set Spread to 0 for mono or no ping-pong, set to 10 for full left right ping-pong.

  • Speed: 3.2
  • Intensity: 6.4
  • Mode: Tremelo
  • Spread: 1.1

Modulation: Chorus

Line 6 has created a very nice, general purpose chorus model that is very flexible. At one extreme, you can set Speed and Depth to 0 and just get a subtle stereo widening through headphones. At the other extreme you can get a rich 80’s chorus that will carry you away. I use chorus sparingly and with moderate settings. Use Predelay to avoid having the chorus kill pick attack and therefore articulation. Spread is set at 10 to give full stereo chorus.

  • Speed: 1.8
  • Depth: 6.0
  • Predelay: 3.2
  • WaveShape: Triangle
  • Tone: 5.0
  • Spread: 10.0
  • Mix: 50%
  • Level: 0.0dB

Delay: Simple Delay

This is the first of two delays. The Simple Delay model is used to create a slap-back delay to create ambience without loosing clarity and articulation that can sometimes happen with reverb. This effect block is on all the time and therefore isn’t assigned to a footswitch. The mix is set so that the delay is barely noticeable when it is turned on. Scale is set at 76% so the slap-back comes more out of the right speaker, giving better ambience in a stereo FRFR amp. Scale at 0% puts the delayed signal entirely in the left channel, 50% puts the delay equally in both channels, and 100% puts the delay entirely in the right channel. Trails can be off since there are no repeats for this delay.

  • Time: 125 ms
  • Feedback: 0%
  • Mix: 18%
  • Level: 0.0dB
  • Scale: 76%
  • Trails: off

Delay: Mod/Chorus Echo

This delay adds an obvious delay or echo effect intended to be more noticeable. The delay is longer, 1/2 sec, and there are repeats. This delay can be used to fill in softer, sparse phrases, or provide even more ambience in situations where there are fewer instruments and you need some fill. This is a delay setting that would often be used to thicken vocals. The Mod/Chorus Echo provides some modulation of the delays, giving a wider, richer overall tone without creating a wooshy chorus on the main tone. Low Cut and High Cut are set to push the delay into the background where it won’t conflict with the main signal.

The Scale and Spread controls can be confusing, especially since they are not documented in the Helix manual. The Mod/Chorus Echo, like the PingPong delay, has two separate channels of delay, with the output of each channel flowing into the other. The delay Time sets the time for the left channel delay. The Scale parameter sets the time offset for the right channel delay line, as a percentage of the left channel’s delay. Scale at 0% puts the delayed signal in the left channel. As the Scale is turned up, the delay is introduced into the right channel with a time offset. As you get closer and closer to 50%, the offset changes until at 50% the delay is ping-pong and even in both sides. As you continue to turn the Scale up towards 100%, the offset is re-introduced, but on the opposite side. The offset gets shorter and closer and closer to zero until at 100% the delay is equal and at the same time in both channels (i.e., mono). Spread appears to control the stereo spread of the modulation, and has no effect on the position of the delay repeats which are controlled by the Scale parameter. This is different with the PingPong delay where the spread determines the stereo spread of the ping-pong, from mono to full left/right. With Spread at 0, the modulation effect (chorus or vibrato) appears to be mono. With Spread at 10, the modulation effect bounces between channels and is in stereo.

I have set Scale high so there is just a little delay offset between the left and right channels. Mod Mode is set to Chorus in order to add a chorus on the delayed signal. Speed is set slow and Depth low to avoid over processing the delays so they appear to decay naturally. Spread is set to 10.0 so that the modulation on the delays is in stereo. Trails are on since there are repeats that fade out when the effect is bypassed.

  • Time: 500 ms
  • Feedback: 29%
  • Low Cut: 155 Hz
  • High Cut: 10.5 kHz
  • Mix: 18%
  • Level: 0.0dB
  • Scale: 94%
  • Mod Mode: Chorus
  • Speed: 1.0
  • Depth: 13%
  • Spread: 10.0
  • Trails: On

Reverb: Hall

Helix has lots of really nice reverbs. I personally like a very small amount of very natural reverb. So I choose the Hall model. I use a short decay to avoid having the reverb make the tone become indistinct. Predelay avoids having the reverb cover up pick attack. Low cut and high cut are adjusted to make sure the reverb doesn’t compete too much with the main dry signal. Mix sets the overall amount of reverb. Trails don’t matter because the reverb is left on all the time, and is not assigned to any footswitch.

  • Delay: 5.3
  • Predelay: 33 ms
  • Low Cut: 220 Hz
  • High Cut: 6.5 kHz
  • Mix: 27%
  • Level: 0.0dB
  • Trails: Off

Dynamics: LA Studio Comp

A LA Studio Comp compressor is placed at the end of the signal chain to take advantage of its unique contribution to the tone, even when its not compressing. This helps glue the effects together and provides a good controlled signal into the FRFR amp. Again, the effect is subtle, but does contribute to the overall tone. The use of the LA Studio Comp, and the Studio Tube Pre after the amp are intended to duplicate what would be typically be done in a studio when setting up for an electric guitar track.

Notice the mix is set at 50%. This provide parallel compression where the compressed signal is mixed with the try signal in order to get the advantages of compression while retaining the clarity and articulation of the dry signal.

  • PeakReduc: 0.9
  • Gain: 6.2
  • Type: Compress
  • Emphasis: 4.0
  • Mix: 50%
  • Level: 0dB;


The Looper is placed at the end of the signal chain so that any effects that were on when the loop was recorded are include in the loop. Playback and Overdub are adjusted so that as overdubs are added, they are reduced in level, leaving headroom to play on top of the loop. If you don’t turn Playback and Overdub down, the loop will become saturated after a small number of overlaps, and won’t leave any room left to hear what you’re playing on top of the loop. See Using a Looper for Solo Gigs for some ideas on how best to use a Looper.

A note on the Helix Looper: the 1/2 FULL speed switch appears to be global. It is not saved with the patch, and remains at its last setting when switching patches. This can be quite surprising since a FULL loop in stereo is only 30 sec long. This may be shorter than most of your loops if they are a full verse or chorus of a song. So glance down when you first use the looper in a patch and make sure the looper is set to be able to accommodate the length of the loop. In 1/2 mode, the looper is twice as long, 60 sec for a stereo loop. This is often long enough for a verse or chorus of a song. But the fidelity of the tone is diminished in this mode. This often doesn’t matter that much because the loops are intended to be background and have their levels reduced anyway.

  • Playback: -2.6dB
  • Overdub: -4.0dB
  • Low Cut: 20 Hz
  • High Cut: 20.0 kHz


The output is set to Multi to feed the 1/4″, XLR, Digital (S/PDIF), and USB 1/2 outputs simultaneously.


This has been a long post to produce a pretty specific patch. This tone may be useful to you directly, or as a starting point for tweaking your own variant. Or it may not be useful at all. But hopefully the thought process for how the blocks were selected, configured and positioned in the signal chain will be useful. Its like the Scientific Method – its not so much what we discover and learn from the method that is important, after all, things change. What’s important is the process through which we explore and discover those new things. There’s always more to learn. Have fun with Helix, and I hope this helps create great tones for you.

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Creating an Acoustic Guitar Impulse Response for Line6 Helix

This post describes how to extract an Impulse Response (IR) from a Fishman Aura Spectrum (Aura) acoustic guitar body image that can be loaded into an IR block in the new Line6 Helix amp modeler. There are some free IRs on the Web that you can try with your guitar to see if this is something that might work for you. If you don’t have a Helix, you can still use the IRs by using a computer and programs like Apple MainStage and SpaceDesigner that support loading any IR in track plugins.


I’ve been trying for years to get a good live acoustic guitar tone. I started with K&K pickups that combined a piezo under the body pickup with a pencil condenser mic. That sounded OK. The piezo wasn’t as bright or quacky as typical under the saddle piezo pickup setups, and the mic sounded good. But it required an external preamp to power the mic and mix it with the piezo, and teneded to feedback a lot.

After seeing James Taylor use a Line6 Variax 700 Acoustic, I got one and used it for years. It sounded better than most under the saddle piezo pickups, had lots of useful instrument models, played nice, and was very convenient, predictable and consistent for live gigs. But it always seemed to have a somewhat “digital” tone that was a bit harsh. I tried to EQ that away, and that helped. But I could never get a sound that made me go wow, and found I was reluctant to play some songs that featured the guitar because the tone just wasn’t that satisfying.

Then I saw that James Taylor used an Aura to get his fantastic live acoustic guitar sound. So I got one and it changed everything. I could now use my small, light Martin 00C-15AE guitar and a nice Taylor 314cd – Neumann U87 body image to finally get the tone I was looking for. In summary, the Variax 700 Acoustic sounded better than the 00C-15AE with just the Fishman under the saddle pickup. But through the Aura, the 00C-15AE sounded a lot better than the Variax. And that little Martin guitar has a magic feel that’s hard to describe.

I play three different instruments in most of our live gigs: mandolin, acoustic guitar, and electric guitar. I use a Collings mandolin with a K&K pickup, the Martin 00C-15AE, and a Stratocaster Deluxe with Tom Anderson pickups for electric guitar. That’s a complicated set of instruments with very different amplification requirements. I’ve been using Line6 amp modelers for years to provide a single device that supports patches for all three instruments direct into the PA. I recently upgraded from a POD HD500X to the new Helix and it really improved the usability and tone of my setup.

The Helix has support for Impulse Response (IR) blocks. So it seemed like it should be possible to use an acoustic guitar body IR block to free up the Aura for other uses, and further simplify my live rig. The rest of this post describes how to extract a body image from the Aura that can be used in a Helix IR block that reproduces the body tone.

Picking the Fishman Aura Spectrum Image

The first step in the process is to pick the image you want to extract. Picking the image requires auditioning the available images to pick the ones that work best for you, your particular guitar and playing style. You could send your guitar to Fishman and get a custom image created, but that’s expensive and probably unnecessary.

Here’s some guidelines for picking the image:

  1. Start with a properly setup guitar with new strings
  2. Use the pick you will use most of the time – using thicker, rounder picks for warmer tone
  3. Either use your computer or Helix with the Aura in an effects loop so you can record a short acoustic guitar loop to simplify the auditioning process. This lets you listen to only the processed sound, and leaves your hands free to select different images.
  4. Take notes on the images you like so that you can narrow down a small set that meet your needs.
  5. Be sure to audition through the speaker system you’ll be using live. What sounds good through headphones might not sound good at all through a speaker system. For example, I really liked the Aura Martin body images through headphones. But through speakers they had a ring and tended to feedback very easily. I suspect this is because of an emphasis around 200Hz that’s what makes Martin guitars sound they way the do and cut through. They might work for you, but I found the Taylor images to more suitable for my needs.
  6. Audition with the guitar still plugged in (if you are using a looper) so that any feedback issues will still be detected. Verify your final selections playing live to make a final check for any feedback issues.
  7. Make sure the Aura has the tone controls set flat, has the blend control set to full body (all the way up), and the compressor is turned off. You want to only hear and capture the body sound. Tone controls, blending and compression will be done outside the IR block using other Helix blocks.
  8. Start with body models that match your guitar directly or at least the body style and wood. You may find that other body images sound better. Don’t get stuck on what’s suppose to be “right”. Experiment with other body styles and woods, and pick the one that sounds best to you, for your style application, and amplification system.
  9. Use the Aura Gallery III app to load additional images into the Aura User patches if needed.

Once you have a set of body images selected, you’re ready to capture and convert them to IRs.

Setup the Audio interface

Helix supports nearly all IRs in .WAV format. However, the Helix application may
automatically change its attributes before sending it to the Helix hardware:

  • Converts all .WAV IRs to 48kHz mono and 16bit.
  • On Mac OS X, as of version 1.04.3, Helix will not load or convert WAF files with sample size of 24 bit. These files need to be converted to 16 bit before loading into Helix.
  • When loading a stereo file, Helix Edit uses only the left side.
  • Shortens (or lengthens) the IR to 2,048 samples (about 43 msec).
  • The user may choose a 1,024-sample version to save DSP. This option simply fades out the IR halfway through.

Helix’s IR blocks only point to a specific IR number (1-128); they don’t include the IR
files themselves. People using your Helix patches will need the same IR file assigned to the same IR index number to perfectly recreate the preset. Otherwise they will need to edit the patch and change the IR index number to where they loaded the IR.

Set your audio interface sample rate to 48000Hz and set the sample size to 16 bits. If your audio interface won’t support this setup, you will need to use an audio utility app to convert the sample rate or sample size before loading into Helix.

Capture an IR for the selected Aura Image

To capture an IR from the Arua, you need to connect the Aura to you computer using your audio interface. Connect an output of your audio interface to the Aura input, and connect the Aura output to an input of your audio interface. You can of course use Helix as your audio interface, but use a large buffer size and long latency to be sure to avoid any clicks and pops. In the examples below, I used a Focusrite Saffire Pro 40, connecting Line Out 3 to the Aura input, and connecting the Aura output to Input 7.

Make sure the Aura is set as follows:

  • EQ on the pickup only and/or EQ controls are set flat
  • Set the blend at 100% (all body)
  • Turn the compressor all the way down
  • Adjust the Volume for good signal level and no clipping (-18dB is a good target level).

To capture the IR:

  1. Open Logic Pro X Impulse Response Utility
  2. Create a project with these settings:
    • Mono project
    • Sweep Channel – the audio interface output connected to the Aura input (3: Line 3)
    • Set the Input to the audio interface input connected to the Aura output (7: IP 7)
    • Set Sweep Length to 10 s.
    • Reverb time is not important in this case because there’s no reverb to capture after the sweep. So set it as low as possible.
    • Save the project using the same name as the Aura image you are capturing
  3. Click the Record button and then click Sweep
  4. Check the levels and make sure there is no clipping. The levels can be adjusted in the IR utility, using the Aura Volume control, or the audio interface input channel gain control
  5. Press Deconvolve
  6. Trim the beginning if the IR to remove any empty content – use the scroll bar to zoom in order to see the beginning or end clearly.
  7. Crop the IR to about 43 milliseconds. If you drag from the beginning, you can see the actual length in samples in the upper right corner. Drag so the length is 2048 and then press Crop to get just that sample.
  8. Add a short fade at the end to avoid any potential clicks.
  9. You can audition the IR using a .aif file that captures a recording of you guitar’s piezo pickup.
  10. Click Create Space Designer Setting… – use the project name as the IR name. This creates a file: ~/Music/Audio Music Apps/Impulse Responses/<project name>.SDIR that is the IR.

Convert the IR file as needed.

You may need to do some conversions of the IR before loading them into Helix. The Saffire Pro 40 cannot be set to 16bit sample depth (neither can Helix), so I had to convert the .wav file. I use felt tip Sound Studio for these conversions, but there are many audio utilities that will work.

  • Rename the .SDIR file to .wav so that it can be loaded into Helix
  • The file should have Sample rate 48,000 Hz and, Bits per sample 16.
    • If the sample size is 24 bits, use Sound Studio to load the IR and re-save it with sample size set to 16.

Load the IR into Helix

Use the Helix app to drag and drop the IR .wav file into an open slot in the IMPULSES pane.

Then add an IR block to your acoustic guitar patch and select the IR index number to the desired guitar body image. Add EQ, effects and preamp models as needed to get the range of tones you need. I’ll have another blog posting on my Helix acoustic guitar patch soon.

If you reconnect your Aura through a Helix effects loop and select the same body image in the Aura, you can compare the sound of your captured IR block with the sound through the effects loop. If everything was done correctly, you should not be able to hear any difference between the two.

Some final thoughts

Using body images as IRs in Helix really opens up the possibilities for using Helix as an effects processor for many instruments besides electric guitar and bass. Body images such as those in the Fishman Aura Spectrum really do turn a quacky piezo sound into the wonderful, complex fullness of a good acoustic guitar.

The Aura images are more than just the body IR. There are complex algorithms used to create them based on the difference between the pickup and body sounds along with phase corrections. How to create an acoustic guitar impulse response shows how to capture an IR for your guitar. Bodilizer is used to analyze the difference between the body and piezo impulse responses. Unfortunately, Bodilizer doesn’t currently provide any means of exporting an IR that can be loaded into Helix. And Bodilizer development seems to be stalled. There are a few acoustic guitar IRs available on the Web, and hopefully Line6 will decide to support some in future Helix updates. But for now, capturing them from a Fishman Aura is a very good option.

You can try blending the body response with the guitar pickup by adjusting the Mix control of the IR block. Adding a little piezo and add definition and attack to the tone without adding too much quack. Some compression can also help tame any piezo attack emphasis and make the guitar stand out better in the mix. You can also use Logic Pro X Match EQ to attempt to match the piezo pickup output to the sound of your mic’d guitar. That will create an EQ curve that you could replicate in a Helix EQ block to better blend between the pickup and body tones.

Good luck, and I hope this helps get even more out of your Helix investment.

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