BIAS review – Positive Grid move iOS amp creation and modelling to a new level

Download from iTunes App Storebias logoAs regular readers here will be aware, as a guitar player, I’m a bit of a fan of iOS guitar amp sim apps such as Amplitube, AmpKit+, Mobile POD and JamUp Pro, all of which I’ve reviewed here on the Music App Blog. Like myself therefore, dedicated iOS guitarists will, of course, have been keenly waiting for BIAS after Positive Grid (the developers behind the excellent JamUp Pro) announced the app and fed us a short trailer for the app a few weeks ago.

The company have gradually released some further details since then but now launch day is here and BIAS (or, to give it its full title, ‘BIAS – Amps!’) is in the iTunes App Store. So, should you be heading over to iTunes, stumping up your UK£13.99, and getting hold of BIAS? I’ve played with both the first release of BIAS today, but also been lucky enough to spend some time with various beta versions over the last 10 days or so. Let’s find out if BIAS has been worth the wait….

The state of (guitar) play

Most iOS musicians are familiar with the guitar amp sim concept; essentially, a collection of virtual guitar amps, cabs, effects and, in some apps at least, microphones and ‘rooms’ that the user can combine in various ways to create their own guitar tones. The iOS apps mentioned above own their heritage to companies such as Roland, Zoom and Line 6 who were the leading pioneers of this technology, first in a dedicated hardware format and, more recently, in software on a desktop computer.

BIAS features 36 default amp models organised into a number of categories and covering a hugh range of tonal possibilities.

BIAS features 36 default amp models organised into a number of categories and covering a hugh range of tonal possibilities.

While the more limited power of earlier iOS devices meant that the original guitar amp sims, although still good, perhaps couldn’t compete in terms of the quality and realism of the modelling compared to the more established hardware and desktop formats, over the last 12 months, the leading apps have definitely been playing catch-up. As well as the increased processing power of newer iOS hardware, this has been assisted considerably by equivalent improvements in the compact audio interfaces available to guitar players. Devices such as the iRig HD, LiNK HD, Sonic Port and iRig PRO all provide very respectable audio quality into your iDevice and this means a better signal for the apps to work their modelling magic upon. Result? Better guitar tones as output.

What is BIAS?

So, given that we already have an excellent crop of iOS amp sim apps, and given that one of the best of them is Positive Grid’s own JamUp Pro, how is BIAS going to carve itself a distinct niche within the market? In short, what does BIAS – which is available as an iPad-only app – offer that we haven’t already got?

Within each of the main amp categories, you find a number of amp models that serve as excellent starting points for your own modifications.

Within each of the main amp categories, you find a number of amp models that serve as excellent starting points for your own modifications.

Let’s start with the two more obvious things. First, BIAS has a strong focus on amp modelling. Indeed, Positive Grid use the term ‘amp design’ in describing BIAS and, as discussed in more detail below, providing you add in the word ‘virtual’, this is an accurate way to think about the app. Yes, like other iOS amp sims, you get cab and microphone/room modelling as well, but there are no stomp-box style effects; the amp is the champ with BIAS.

However, before you start to think that Positive Grid have lost the plot, consider the second key point; BIAS is not so much a replacement for JamUp Pro as a compliment to it. Essentially, while BIAS will quite happily work on its own (and includes Audiobus and Inter App Audio (IAA) support so you can use it in a wider musical workflow), BIAS and JamUp are designed to work together. You can use all the detailed and powerful amp design features of BIAS and then pass your personalised amp design over to JamUp Pro to embed it into a JamUp preset with all your favourite stomp box effects.

Of course, Positive Grid are also keen to point out a third – and perhaps the most important – thing that BIAS brings to iOS amp modelling; a hike in the quality, flexibility and realism of the results. More on that in a minute or two.

Basic BIAS

How many components within your virtual amp do you want to tweak? Don't worry - BIAS lets you do as much or as little as you prefer.

How many components within your virtual amp do you want to tweak? Don’t worry – BIAS lets you do as much or as little as you prefer.

Positive Grid claim that BIAS offers ‘the most complete, accurate and versatile amp modelling available in the world’. That’s quite a statement but the basic spec of the app is most certainly impressive.  For example, unlike some iOS amp modellers, where you get a few amp models to start with but have to use IAPs to expand your choices, BIAS is supplied with 36 amp models straight out of the box. These cover an impressive range and are organised into small groups based on the general tonal properties. Categories such as Clean, Glassy, Blues, Crunch, Hi Gain, Metal and Insane might be expected but these are joined by Acoustic and (thankfully) Bass categories.

Want to change your virtual valves? Go on then....  and no danger of electrocution :-)

Want to change your virtual valves? Go on then…. and no danger of electrocution :-)

As indicated above, where BIAS brings something new to iOS amp modelling is in the level of control offered. Once you have picked a basic amp model as a starting point, you can go in and tweak all the individual components. The interface used here is similar in style to JamUp, with the whole signal chain shown along the top of the screen and more detailed controls for the currently selected element of that chain shown in the lower half.

In terms of that signal chain, the Custom Panel section allows you to customise the look of the main panel as well as adjust the amp’s actual settings (gain, bass, middle, etc.). Beyond that, however, things get a bit more interesting – and perhaps a whole lot more geeky in a ‘guitar amp technician’ sort of a way – as you can then dip into the Preamp, Tone Stack, Power Amp and Transformer sections of the amp and tweak all sorts of controls and settings.

For example, in the Preamp section, you get a whole host of controls to adjust and can even select the virtual tube types. The Power Amp and Transformer sections are an equal geek-fest for tone-hounds. Thankfully, each of these sections also has a preset system so, if you don’t want to dig too deeply, you are still offered a huge range of combinations to experiment with, without risking a virtual amp melt-down.

BIAS offers two EQ modules with plenty of additional tone shaping possibilities.

BIAS offers two EQ modules with plenty of additional tone shaping possibilities.

The signal chain also includes two EQ sections, each with up to eight EQ controls. This is enough to shape the tonality and, as you can place these two EQ units at any position in the signal chain, there is plenty of flexibility. Further tonal colour is available via the Tone Stack section. There is perhaps less detailed control here but some useful presets  – British Top Boost, American Tweed, etc. – that can help push your sound in the direction you are looking for.

The other section is the Cab modelling. There are some 20 different cab types to choose between including all the usual guitar suspects (1×12, 2×12, 4×12, etc.) and some acoustic and bass-friendly cab types. Aside from picking the cabinet type, you can also select between two different mic models and then position the mic relative to the speaker cabinet. This includes the option to move the mic closer to or further away from the speaker cab so you can change how much of the virtual ’room’ (ambience) you also get in the sound.

The global Room Control settings allow you to dial in a virtual room with a range of characteristics.

The global Room Control settings allow you to dial in a virtual room with a range of characteristics.

Aside from the input and output level LED meters and controls, the very bottom of the main display also provides access to the Noise Gate and Room Control options. The former obviously helps to keep things under control when you are using the higher gain amps while the latter combines with the mic type/position settings to give a sense of the virtual ‘space’ in which the amp is sitting. There is plenty of control here and it is possible to conjure a sense of both small or large and warm or bright rooms. Or, of course, just to have everything totally dry. The bottom panel also includes a Quick Snap section where you can easily save up to eight snapshots of your settings for easy recall and comparison.

There is, however, also a full preset system available via the disk icon located on the top-strip of controls. Equally, this top-strip also provies access to the apps key settings and help options, the ability to share your tone via Facebook and that all-important link to JamUp (the chicken-head knob icon).

Sound control

Of course, all this amp tweaking, tube changing and mic modelling isn’t worth diddly if the sounds themselves don’t cut the mustard. However, guitar tone is a very personal thing – one player’s sonic Nivana is another’s worst nightmare – so opinions here are always going to have an element of subjectivity.

BIAS includes an excellent selection of different cabinet models to choose from.

BIAS includes an excellent selection of different cabinet models to choose from.

That qualifier made, as someone who generally likes their neighbours and would prefer to preserve the sanity of my family, I’ve always been a fan of guitar amp modelling as a technology; most of the tone without so much of the aggravation and noise that owning and using multiple amps tends to bring. As a consequence, over the last 15 years or so, I’ve been lucky enough to try a huge number of products in this field, whether hardware-based (where I’m very attached to Line 6 but can also appreciate products from the likes of Roland, Zoom, Vox and others) or in software (NI’s Guitar Rig and Line 6’s Amp Farm for example) and, since getting addicted to iOS music apps, I’ve also used all the main iOS guitar amp sim apps.

So, with all this background experience, for pure sound, where does BIAS stand? In terms of the raw guitar tones that can be created (that is, without a slather of stomp box effects that can hide a multitude of amp modelling sins), I have to say that BIAS is undoubtedly the best guitar amp modelling I’ve yet heard from my iPad. For the diversity and quality of tones right out the box, I’d previously have given Mobile POD that nod (although you do, of course, have to buy a Sonic Port to use it) but BIAS I think BIAS has an edge and, in terms of sheer tweakability, it certainly has the upper hand.

It's not just the preamp you get to tweak; almost every component is available in each stage of the amp's signal flow.

It’s not just the preamp you get to tweak; almost every component is available in each stage of the amp’s signal flow.

However, I don’t just think BIAS competes well with other iOS guitar amp sims; I think it can also go up against some of the better of the desktop amp modelling software and hold its own. In terms of the basic tones, I’d have absolutely no problems using BIAS in my own recording projects. While I don’t think any modelling – quite yet anyway – competes with the experience of recording a top-notch valve amp in a good recording room, when it comes to listening back to the tone you have recorded without the hyped-up experience of the amp in your ear, BIAS is very close indeed. Indeed, close enough but without all the hassle, noise and expense of actually owning the real versions of the 36 amps that BIAS models. Oh, and when you want to tweak how those amps operate inside, you don’t risk electrocution :-)

Does BIAS sound good? No, it sounds great….  The clean amps go from squeaky to glassy with absolute ease. The blues amps are set to break up really nicely and, if you want to push them a little further, just dip into the Preamp settings and add some extra tubes stages or a little more distortion. The crunch models can give you almost any classic rock rhythm tone your AC/DC heart might desire, while if you want to break out the modern rock tones, the hi-gain and metal amps have it covered and, again, if you want to push things a little harder, just tweak the Preamp settings. Or, of course, dip into the insane options where you will find enough gain available for even the trashiest of thrash metal.

You can even customise the look of your amp to create your own 'amp branding'.

You can even customise the look of your amp to create your own ‘amp branding’.

The inclusion of the bass models is also most welcome and, while you only get four amps as a starting point, given the level of customisation that is possible, you can carve out a huge range of possible tones. Bass players ought to find BIAS just as interesting as most six- or seven-string players.

The ‘acoustic’ section is also worth a close look as, while it includes an amp suitable for an acoustic guitar, it also contains both keyboard and vocal amps. If you want to create an amp model to put your synths or vocal mic through, there are some interesting and useful possibilities here. The only one I haven’t yet worked out how to get the best from is the acoustic sim amp. I assume this is meant to allow you to create a simulated acoustic guitar tone from an electric guitar input but, if so, I wasn’t particularly convinced with the results during my own testing.

Amp swap shop

As well as BIAS being launched, JamUp (both the free and paid versions) has been updated to allow the integration with BIAS. While I’ve only been able to experiment briefly with this, the implementation does appear to be very slick. Having designed your amp within BIAS, you simply tap the JamUp icon in the top-bar and your custom amp from BIAS immediately appears within JamUp.

My first BIAS custom amp design ported over to JamUp Pro XT - how cool is that?

My first BIAS custom amp design ported over to JamUp Pro XT – how cool is that?

In addition to being able to then adjust the amp’s controls in the usual JamUp fashion, you can also add the various other elements to the signal chain such as your stomp box effects. Indeed, the amp model is then added to the amp model collection within JamUp so it becomes available to include in any JamUp editing that you might do; you don’t need BIAS running the the background to use the model in JamUp. When selecting a BIAS created amp within JamUp, you also get the option to ‘Edit in BIAS’, both during the selection process and via the small BIAS icon that appears in the top corner of the amp head graphic.

The way the two apps work together is very designed indeed and, as users can now create as many different amp variants as they are ever likely to need, the only downside I can see is for Positive Grid’s sales of amp model IAPs. For the user, it’s all positives.

BIAS appears as an IAA app within Auria.

BIAS appears as an IAA app within Auria.

As mentioned earlier, BIAS includes both Audiobus and IAA support straight out the box. I had no problems with either of these and could happily record into Cubasis via BIAS when using Audiobus. Equally, BIAS appeared as an IAA app within Auria so I could use it as an insert effect there without any issues. In both Audiobus and IAA modes, BIAS includes the usual buttons/icons that allow you to flip back to the host app for ease of workflow.

Am I BIASed?

The Audiobus support seems to be very well implemented.

The Audiobus support seems to be very well implemented.

For me, BIAS has three key strengths. First, included in the price, it offers a huge selection of virtual amps types that cater for almost any possible guitar tone you could possible imagine (and probably a few that you couldn’t) and also covers the basic needs of bass, acoustic, keyboard and vocal amplification. These serve as an excellent starting point for you to explore, edit and create your own designs from. Second, in terms of the detailed level of control it offers you to craft your virtual amp’s tonal character, BIAS is streets ahead of anything else under iOS.

These two things might be more than enough for most guitar and bass players to pay a visit to iTunes and cough up their UK£13.99 but it’s the third strength that is the killer; BIAS just sounds great. Whether you want clinical and clean, warm and overdriven or aggressive gain to shove in your listener’s face, BIAS can do it all. You might not give two hoots about all those virtual valves and tone stack settings you can tweak but you should care that Positive Grid have, to my ears at least, just raised the bar in terms of the sonic quality of iOS amp modelling. If you are an iOS guitarist who is really serious about their guitar tone, then BIAS is an app not to be missed. Highly recommended.

BIAS -Amps!

Video demo of BIAS from the Music App Blog

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    1. Very good review, really useful, thanks.

    2. Thanks for the review! I seen some comments on the web that BIAS can be a bit taxing on iOS resources. Some other people have noted that thing run better if you import the amps into JamUp XT. Is BIAS I should even bother trying on an iPad 2 (which runs JamUp and AmpKit just fine), or do you recommend one of the newer devices?

      Also, am I missing something – how does BIAS not completely break the pricing structure of JamUp XT? BIAS comes with 36 different amps, and they’re supposedly BETTER than the amps already in JamUp…and they cost $15 – $20 with one purchase of the app? The individual amps within JamUp cost $4.99, with bundles either $4.99 or $9.99. What’s the catch?

      • Hi Jeff, thanks for the comments. I ran BIAS on my iPad 3 OK before I upgraded to an Air. It worked OK but I’m sure you are right – BIAS is quite demanding in terms of processing requirements – although the sound is well worth it :-) And, yes, you would imagine that BIAS would probably mean the IAPs in JamUp Pro are not going to see as many sales…. but I guess that’s a problem for Positive Grid rather than us users and I’m sure one they have done the maths on….

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