Quad Cortex: Why I’m Passing On It

Neural DSP’s Quad Cortex is finally shipping. As one of the early backers, I have the chance to get one of the first units, before they hit the shops.

I’ve decided not to.

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The Quad Cortex is a new profiling / modelling hardware unit from Neural DSP. I was one of the early (“Tier 1”) backers, when it was first announced. Now that it’s available to buy – and we’ve got early reviews from experienced YouTubers – I’ve decided it isn’t the right unit for me at this time.

  • My main interest in the Quad Cortex is for live gigging, and it’ll be 12-18 months before that’s likely to resume. If I bought a QC now, it wouldn’t get enough use to justify the purchase price.
  • The features I need for live gigging are either reported to be surprisingly weak (delays, reverbs, modulation effects) or completely missing (looper, ground lift for two fully-stereo paths through the unit).
  • The features I’d use in the mean time at home are either reported to be not quite there (profiling – although definitely better than what the Kemper can manage) or completely missing (desktop editor, ground lift on the send-to-amp output).
  • I’m concerned that some of the features I need (looper, the ground lifts on those outputs) may require a hardware revision and/or will need me to buy two Quad Core units to work around them.

On balance, I need to wait for a (hypothetical) Quad Core rack unit or mk2 revision that’s a little more mature. Or wait for Kemper to rise to the challenge and release a new unit that can compete with the Quad Cortex.

And, in the meantime, I can use that money to buy an actual tweed amp instead.

A Year Too Late For Me … Or Maybe A Year Too Early?

Thanks to both the production delays and how life has changed since the Quad Cortex was announced, the release has come at a time where I just don’t need it.

Last year, I was looking at the Quad Cortex as an all-in-one gigging solution. We’d done a gig in 2019 where the sound engineer had thrown some delay and reverb up on one of our cover songs, and I loved it. It made me realise that we should incorporate pre-planned effects into future gigs.

The Quad Cortex seemed like the perfect device for that role, thanks to its ability to support multiple, independent input paths. It supports phantom power for a mic, and (especially important) enough balanced outputs for two stereo outputs to a venue’s sound desk.

Unfortunately, it’s now been over a year since we were legally allowed to get together to rehearse. Realistically, I don’t think we’ll be able to start rehearsing again until 2022. Even if the restrictions get lifted this year, that doesn’t make it safe. And it probably won’t be safe to gig until we’ve all had boosters to address the more concerning mutations that are floating around.

That still leaves the possibility of home use, right? Well, not for me, to be honest.

This year, my focus is really on learning to record (and practicing with!) acoustic guitar. If I buy the Quad Cortex, no matter how good it is, it’s just not going to get enough use to justify buying it.

Once that’s out the way, and my old Phase 1 material is recorded, I’ll be moving on to focus on recording Phase 2 – and I’m already planning on using my Boss Katana 100 head for that. I wrote the Phase 2 music back in 96/97 going through one of those Boss multi-effect pedalboards direct into a Tascam 4-track. The Katana, with its solid state clean sound, gets me straight into that ballpark.

Based on my current rate of progress, that’s going to keep me focused deep into 2022.

So yeah … I just don’t need the Quad Cortex right now, and it’s going to be 12 months or more before I have a need for it. That might turn out to be a good thing, because right now, I’m not entirely sure that it’s ready.

The Initial YouTube Reviews Were A Mixed Bag For Me

Neural DSP sent units out to a bunch of YouTube channels to review (as you do, in this day and age). Those early reviews definitely dampened my enthusiasm for the Quad Cortex.

In particular, five concerns stood out:

  • Profile accuracy
  • The quality of the non-dirt effects
  • No desktop editor
  • No ground lift
  • No looper

It might seem a bit odd to call out the accuracy of the profiles. I mean, it’s clear that it does create captures that sound better than the Kemper does.

(We’re already seeing a knock-on effect of this: on the 2nd hand market, Kemper prices are starting to fall for the first time that I can remember.)

So what gives? While everyone says it feels great to play through, everyone’s also having to go into the captures and make adjustments to get them sounding close enough. That’s a concern for me. As a general rule of thumb, Kemper profiles start to break down pretty quickly when I make changes to them. It seems reasonable that the Quad Cortex captures are likely to have a similar limitation.

Why does this happen? Each device only has a static snapshot of your signal chain to work from. They doesn’t know how your signal chain reacts when you adjust any of the knobs on your real amp, or on any pedals. They have to fall back to a best-guess approach, and the more you change the setting, the bigger the difference between that guess and the real world.

(As an aside, why has no-one made a profiler that doesn’t use a single static snapshot?)

I think I’ll be happier waiting a year or two, until the firmware has had an opportunity to mature a bit. And not just when it comes to captures …

It was a big surprise to consistently hear YouTube reviewers call out the non-dirt effects (the ones we can’t capture for ourselves) as being worse than the effects in the Kemper. That’s a pretty low bar to clear, in my opinion. While Kemper have put a lot of effort into improving the onboard effects in the last few years, they’re still hampered by the limitations of a decade-old hardware platform.

(Officially, Kemper haven’t updated their hardware platform since launch in 2011. Every Kemper firmware release has to be backwards compatible with those decade-old units.)

I’ve no doubt at all that it’ll get sorted in future firmware updates. The Quad Cortex has the underlying hardware to handle it. I mean, I don’t remember anyone ever raising concerns about the non-dirt effects in their desktop plugins. Neural DSP just need a bit more time to be able to address it, and I’d rather wait until they do.

The lack of a desktop editor (yet!) means that the Quad Cortex doesn’t suit me. Neural DSP have done fantastic work on the physical interface of the Quad Cortex. Making the foot switches double up as rotary controls? That’s game changing, it really is.

Unfortunately, here at home, the Quad Cortex is either going on the floor or on a shelf somewhere. It isn’t going to be sat on my desk, and that means that I need to be able to control it from my laptop.

Those are the shortcomings in the Quad Cortex that have put me off buying one today. The profile one is probably just disappointment about an oft-delayed unit not quite living up to the hype (and having lived with similar Kemper disappointments for several years). The other two? They’re complete deal-breakers for me and what I want to use the Quad Cortex for.

I’m not sure that all of my concerns can be addressed through firmware alone though …

Does The Mk1 Hardware Have Omissions?

Now, this one confused me at first, so bear with me while I get this straight. And my apologies in advance in any of the confusion has remained in this final draft of my post.

According to the early YouTube reviews, the Quad Cortex’s send-to-amp output (which is used for making captures) doesn’t have a ground lift support. Even in a studio setting, experienced folks like Pete Thorn have had to resort to using an external device to work around that.

At first, I was worried that this meant the Quad Cortex might not have any ground lift support at all. That’s a complete deal-breaker for live gigging.

Fortunately, there is some ground lift support in the device. The manual for the Quad Cortex shows software-control ground lifts on the two main inputs, and on some of the outputs.

I don’t think enough outputs have ground lift support to work for me in a live setting, though.

I’m trying to use one Quad Cortex for both Tess (vocals) and me (acoustic guitar). (Remember, Quad Cortex was originally marketed as being powerful enough to support four independent paths, so this is a very reasonable ask.)

To achieve that:

  • I need one set of stereo outputs for effects send / return. It looks likes these do have a ground lift.
  • I then need two more sets of stereo outputs (one for vocals, one for guitar) to go to the venue’s PA / sound board. It looks like only one set of these have a ground lift.

I think the only way that I can get two sets of stereo outputs with ground lift is to give up the effects send/return feature. I don’t want to do that,

Or, we have two Quad Cortex units (one for vocals, one for guitar). Not only is that twice the price, and twice the faff at a gig, using one unit also helps us eliminate mistakes live.

And then … why is there no looper? This omission has me a little nervous, because decent loopers need a little bit of hardware support.

  • They need somewhere to record the loops to, and enough storage to handle multiple layers at once.
  • They also need somewhere to store the loops when the power is disconnected. A looper that forgets all the loops between sessions is a bit limited for gigging with.

If the Quad Cortex has the physical hardware, then Neural DSP would have had to have created a looper feature just to test it. It’d be a brave soul who shipped the hardware first, and then wrote the tests for it post-launch, for sure. It could be that they have tested the necessary hardware, and just ran out of time to make the software side of it good enough to release. That is perfectly plausible.

Either way … at this price point, I don’t want to spend money on a device that may have hardware shortcomings that restrict my planned usage – especially as it looks like I might have to buy two Quad Cortex units for gigging with just to work around the hardware. I’m much better off waiting to see how others get on with it first.

So yeah, I’ve got plenty of misgivings for how I plan on using the Quad Cortex, and the longer I spend on writing up this post, the more I’m spotting.

I also need to be honest with myself: there’s better things to spend that kind of money on, for me at least.

It’s Time For A Real Tweed Amp

Regular readers will know that the ‘tweed tone’ (whatever that might be) is my thing. Although I grew up on Strat knockoffs into Marshall-like amps, I’ve come to realise that a great vintage-voiced Les Paul into a tweed-like signal chain suits the musician that I am today.

But I don’t actually own a proper tweed amp. Heck, I’ve never even played through a proper tweed amp.

Well, I kinda do own one. I’ve got the Synergy BMan module, which will be based on Fender’s 5F6 circuit from the Bassman. Since I got it last year, it’s been my go-to Synergy module. It sounds great with the gain cranked up.

Sadly, there’s no sign of Synergy releasing a 5e3 (Fender’s Tweed Deluxe) module. They seem to have found their market down the modern metal / high-gain route, and they seem to be focused on that for now.

So … why don’t I use the money set aside for the Quad Cortex to get myself a modern reproduction tweed amp, based on the 5e3 circuit? (Assuming I can find one that won’t peel the paint off the walls …)

I think I’ll be much happier doing so, and that’s what it’s all about, right?

Will I Get A Quad Cortex In The Future?

I still want a multi-effects unit to gig with, and that unit needs to support both my acoustic guitar and Tess’s vocals simultaneously.

Last year, I thought Quad Cortex could be that unit. Small, lightweight, portable, with presets, it certainly had the potential.

That shortage of outputs with a ground lift though … looking at the manual, I can’t see how the current hardware will fit into our gigging needs. It really looks like we’ll be forced to buy two of them to do the job, just because of that small oversight.

And I’m reluctant to do that.

Final Thoughts

I think the Quad Cortex has suffered a bit from being birthed during these historic times.

In normal times, Neural DSP would have been able to seed prototype units out to working musicians. In turn, these musicians would have put them to the test in rehearsal, in the studio, and out at gigs. The feedback from this field testing would have helped to identify any missing hardware capabilities (like enough ground lift support for two fully-stereo paths) at the prototype stage … the kinds of things that can’t be fixed in firmware alone.

These aren’t normal times.

I’m sure the Quad Cortex will be a commercial success. It seems to have everything that Neural DSP’s plugin users would want in a hardware unit, and enough of what the home Kemper owners need to eat into that market.

I suspect that it’ll have its biggest impact on the wider market. After all, some of its competitors are starting to get a little long in the tooth.

The main competitors are the decade-old Kemper, the seven-year old Helix, and the three and a half-year old Axe FX 3. Of these, it’s the Kemper that it’ll inevitably draw the most comparison with, especially as they have both the most overlapping features and the most polar-opposite user experience going.

Surely, it’s now only a matter of time before Kemper is forced to up their game and release new hardware with much more accurate amp profiling. Who knows? Maybe we’ll see a new competitor enter the market too, especially if Kemper are slow to respond.

After all, there’s all those ageing Kemper units in studios around the world to replace. That is a sizeable market for someone to go after.

I wouldn’t be surprised to see that someone be a more pro-oriented Quad Cortex rack unit, with a little less tech bro attitude and a little more maturity. I don’t think it’s likely, but I think I’d enjoy that unit quite a bit if it ever happened.

9 Replies to “Quad Cortex: Why I’m Passing On It”

  1. i think its just too immature yet. they hiked the price $250 even bore its even really out to the majority which is a bad move. At 1850.00 us it needs a ways to go to get to where helix/kemper/fractal are.Maybe in a year or so it will be closer but by then line6/fractal and bluampx will likely have new stuff out so qc will be playing catchup for a while. I see on thegearpage buys who already have every top tier modeler getting one just to add to thier stable and flame anyone who questions its future which is so lame.

    1. I must agree: considering their wealth of experience with their plugin range, the Quad Cortex does look like it wasn’t really ready for release.

      Unfortunately, software is never going to fix my issues with it. Those missing ground lifts! Even the Kemper has those, and it’s a decade old device. That was a totally avoidable mistake. I just hope they fix it when the next hardware revision gets done.

  2. Unless you don’t know how to dial in an amp, the Fractal is still the best modeler you can get. Top tier effects. A plethora of amp models and cabs. Get an inexpensive amp pre, and be done with it. Lack of a desktop interface in the QC is huge. It is more like a Headrush Gigboard than it is a Kemper or Line 6. Except the Gigboard actually sounds good at this point with the current range of effects. Amplifire is another contender that sounds as good or better than the QC at this point, and has a mature desktop interface, no touchscreen display. We’re about 2 generations away from the major players having perfected the amp modeler.

  3. Neural DSP should have waited until NAMM 2021 to announce and Fall 2021 to ship. Instead, they have disappointed both the retail channel and the customer with the ridiculously long wait. Now the customer feels the one-two double-whammy combination gut-punch & roundhouse-kick to the noggin, given all of the reliability and noise issues. Then there is the ‘where’s-the-beef’ moment 21 months later
    as customers are still waiting on initial feature promises like a looper and plug-in support, the lackluster fx sound-quality notwithstanding. Meanwhile, Moore’s Law’ has a tendency to ravage manufacturers who wait to find their own shoelaces. As such, the QC hardware platform is already ‘last-gen’ and everybody who bought one is going to find themselves albatrossed with a rev-1 shell requiring hardware revisions for proper grounding, more looper memory and SPDIF, just to name a few. Few big-name multi-platinum artists use the Quad Cortex and any that do are ones that were given it for free to lend false appearances in order to entice the otherwise unwitting into the ultimate overhyping, if not a flat-out lie.

    1. I’m not sure I agree with all of that.

      The QC was announced in the before-times, and I don’t blame Neural DSP for manufacturing delays due to the pandemic. Supply chains around the world have been disrupted, and many other pre-announced products have struggled too.

      Is the QC hardware ‘last gen’? I’m not sure that’s the case either. All of its main competitors are using hardware platforms that are far older, and they continue to sell well. Moore’s Law has been dead for years for practical purposes, so I don’t buy that argument.

      Is the QC a little disappointing, especially given that Neural had 6+ extra months to improve on the concept? Yes, that I agree with. I definitely feel that, somewhere along the way, someone took their eye off the ball about the details of the hardware itself. No-one ever complains about their plugin software, so it’s a bit baffling that the launch firmware didn’t live up to that.

      I don’t think it’s fair to criticise Neural for sending free units out to artists and influencers. This is how the industry works, and they did nothing unusual there. Pretty much all the QC reviews I saw from influencers were clear that the QC was a mixed bag. I didn’t see anyone misleading their audience on that.

      – Stu

      1. Moore’s Law has not “been dead for years”, though it is approaching it’s end. QC hardware is clearly newer than the competition, but insufficient memory for looping isn’t a Moore’s Law problem.
        Standard Operating Procedure in all tech markets (and yes, this is one) is a rush to market to gain attention and thus market share as quickly as possible. Investors demand a return on their investment. This typically results in many product deficiencies or problems to be cleaned up in later releases or versions. Poorly implemented effects may be solved via download. Not so for insufficient memory, and with surface mount tech to keep manufacturing costs down, Neural may have backed themselves into a corner here.
        Most consumers don’t really care about the investors, older world events or the tech. They want the product to do what it says and the company to stand behind what they promise. The higher the price point, the higher the expectation.
        BTW, your ground lift issue is easily solved, by you. for about $20. Not really a reason to pass on an $1800 piece of gear that otherwise would meet your needs, or soon will via a simple software download/upload..
        Personally, I’m still an old analog person who prefers analog sound, warts and all. I found 5 or 6 great tones to be far superior to 1000’s of mediocre possibilities. I’d rather spend time creating and playing than messing with gear. Buy the Tweed, you’ll never regret it like you will in 5 years when some new digital piece repeats the above cycle.

  4. Looking on the QC forum tells the whole story.
    I was aying with the idea of getting one, but not with such a lame support. If you’re buying yourself into a game, your needs must be heard –
    or you somewhere else (to the competitors)

  5. Our studio has primarily used Kemper and Fractal gear which have been real workhorses but they aren’t keeping up with the needs and requirements of musicians. When new products come out there is always a huge amount of hype for the launch and the QC has been the top of the hype for over a year since launch but this time, the hype is warranted. Everything about this gear is state of the art, forward thinking and incorporates almost every feature found in existing modelers. You will see negative reviews for just about anything these days but from my perspective, the QC seems to defy and maintain strong positive reviews so we gambled on the hype, sold off some of the legacy Kemper/Fractal gear and migrated to the QC and never been happier.
    This is truly gear for the forward thinking musician.

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