Digital mixer for electronic instruments

[jvq]

Hello SOS Forum (first post!),

I make electronic music as a hobby using synths and drum machines. I mix on analog mixers (AH MixWizard as main mixer, with a Mackie VLZ4 as a drum submixer). I sometimes read about fancy digital mixing desks (AH Qu, SQ, Behringer X32, Soundcraft Si, Presonus Studiolive etc.) but I get the impression they are no suited for what I do, because (apart from the AH Qu) they tend to only have XLR inputs which I don't quite trust.

I should add this is more about me developing my general understanding of this gear than about solving an actual need. The analog desks I have now work fine. The only advantage of digital for me personally would be to have compression and a parametric EQ per channel, which opens up some mixing/production possibilities compared to how I work now. I am aware that "use a DAW" is a more obvious way to have more EQ's etc.

Back to digital mixers with line sources. I don't have an issue with soldering XLR conncetors onto my cables, but I don't like the thought that accidentally enabling 48V phantom power is even possible. On a mixer that only has XLR inputs I feel like I'm a button press away from frying one of my synths. One can work around that with DI but in my case that would be quite expensive - if I had a 16 channel digital mixer, I would need 16 DI's or isolators to make use of its full track count.

This leads me to the conclusion that these digital mixers are fundamentally unsuitable for my use case: a mixer fully populated with line level signals. My question is, am I right? Or am I perhaps too paranoid in my distrust of XLR inputs for synths?

[jvq]

A related but different question. Some professional gear has line level XLR outputs. One may end up plugging such outputs into a mixer with XLR inputs and mic preamps. Can one expect professional line level XLR outputs to be protected against exposure to 48V phantom power?

For example a digital mixer like the Soundcraft Si Expression 1 has only XLR outputs. Would those be safe when exposed to 48V?

My concern about 48V frying other gear might be overblown.

[Sam Spoons]

Behringer XR18 has 16 combi TRS/XLR inputs (plus one stereo input on TRS jacks), is an 18 x 18 USB audio interface and costs €379/£330. No faders though but control is available using iOS, Android, Mac OSX or Windows apps. Behringer's DAW controller, The X-Touch, gives you 9 motorised faders, loads of dedicated buttons and a Jog wheel plus LCD scribble strips, can control the XR18 as well as the DAW and costs €349/£300.

I have an X32 Compact and, as you say, the inputs are mostly on XLR so a bal/unbal XLR/TS lead could end up with 48V on the synth outputs. Is there a simple way to make leads that can protect against accidentally applied Phantom power? If not you'd need to budget for a SD16 stage box if you went the X32 route (€499/£426).

[Bob Bickerton]

The Zoom LiveTrak L-20 has 16 combo XLR/Jack inputs too, but the manual is unclear as to whether phantom is passed to the line inputs as well - something to check with combos....

Bob

[Sam Spoons]

I have checked that on my XR12 and can confirm the TRS input does not carry spook power when it is active on the XLR side of the combi socket. TBH I'd be surprised if any did, my Mackie DL1608 has four combi sockets which are designed to accept balanced or unbalanced ¼" jack leads, I'll check it next week.

[The Elf]

I'd say you're being too paranoid, but you do have some justification.

I have been using a couple of Zoom LiveTrack 12s with a rig of synths and now use a Behringer XR18. Both have combi sockets. I'll use an XLR-to-XLR whenever possible (a far better connection than jacks IMO), but if the synth has a jack I'll use a jack-to-jack. I use balanced cables throughout. I will not use jack-to-XLR cables.

I think that Behringer missed a trick not giving the X32 combi sockets. I know many synth players that have avoided the X32 range for this reason, and I'm now amongst them.

[James Perrett]

TBH I'd be surprised if any did

One of the items reviewed in last month's SOS magazine fed phantom power to its jack inputs so it isn't unknown although it should be rare. I don't have my copy handy so can't check to see exactly what it was.

[Hugh Robjohns]

You're probably thinking of the Golden Age Premiere preamp:

https://www.soundonsound.com/reviews/golden-age-premier-pre-73-preq-73

Although most equipment is designed such that phantom doesn't appear on the jack side of combi-XLRs, I've come across a distrurbing number that do... So I always test rather than assume!

I think the OP is right to be concerned about the potential for damage to synth's and other line-level equipment from phantom power. Some is robust and safe, but certainly not all and, once again, I'd never assume anything was phantom-safe (unless I knew it had output transformers!).

Having said that, I connect my synths to the XLR inputs of a Yamaha DM1000 without concern because I trust myself not to activate phantom on those channels. But if the desk was being used by someone else I'd consider connecting via passive DI boxes to be safe!

H

[jvq]

Thanks for all the replies everybody!

Nice to know that combi XLR can be safe.

While those new iPad-only mixers like the Behringer XR 18 have nice features the tablet experience is not my cup of tea.

It so happens that cats roam my studio and they can and will engage occasionally 48V on some of my MixWizard channel strips. Lucky for me the MixWizard has the luxury of TRS inputs.

I suppose some of these digital mixers are just strongly geared towards microphone-heavy use cases (live sound?). I think I'll stay with what I have for now.

[The Elf]

While those new iPad-only mixers like the Behringer XR 18 have nice features the tablet experience is not my cup of tea.

Not mine either. Happily the X32 (and X/XR derivatives) aren't iPad only! There's software for PC and Mac too.

I use an Ethernet cable safely connected to the same laptop for which it's providing a USB audio interface. I don't have much time for tablet devices, and I certainly wouldn't trust a WiFi connection for the stage.

So don't dismiss the X devices on the basis of requiring a tablet - that definitely isn't the case!

[Mike Stranks]

... and as Hugh says, if you used some DI boxes as 'buffers' and went into mic inputs you'd avoid potential phantom horrors.

Check-out Orchid Electronics for very good and remarkably priced DIs. They have a a big fan-base here!

FWIW, I've experienced phantom into line outputs before - several times. Sounded horrible, but no permanent damage. But better safe than sorry!

[OneWorld]

I think that Behringer missed a trick not giving the X32 combi sockets. I know many synth players that have avoided the X32 range for this reason, and I'm now amongst them.

I agree, I am ruminating over which digital mixer to get and the lack of combi sockets goes against the x32 which otherwise seems quite a capable mixer

[CS70]

It so happens that cats roam my studio and they can and will engage occasionally 48V on some of my MixWizard channel strips.

Cathom power!

Having a four years old child, I've found myself recently thinking why the 48v switches don't have a cap or something, like a "fire" button.. luckily one more year and I'll likely be out of danger.

[James Perrett]

Having a four years old child, I've found myself recently thinking why the 48v switches don't have a cap or something, like a "fire" button

Studiomaster had the right idea when they used recessed phantom power switches on their desks. You had to use a pen or some other small implement to switch them on (although maybe a 4 year old's finger might do it).

[jvq]

Thanks for all the responses everyone. I still haven't quite let go of this idea of buying an AH SQ5.

While I could solder up a bunch of unbalanced cables with male XLR connectors on one end, it does not really make sense to take the risk of damaging the equipment on either end (synths or mixer). While buying 16 channels of DI or transformer isolation is not cheap, I think it makes sense as a form of insurance against 48V lightning strikes.

Which leads to the question of what DI / isolator to get. I am currently considering the following options:

- 2x ART T8: nice and compact, at about €28 per channel
- 8x Orchid Dual Channel Micro DI: also about €28 per channel

I don't like the arrangement of inputs / outputs on the 8-channel Orchid passive rack DI, at €35 per channel. The unit also appears to be twice as deep as the Art. It would be awkward to have cables poking out both ways. Something like the Radial Pro-D8 has the same size / orientation problem at the even higher price of €122 per channel.

From a "cable mess" point of view, I think the ART T8 would work the best for me with TRS ins and outs on the same side. I would keep my existing cables up to the mixer (terminated in TS), plug them into the Art boxes, and use short TRS -> XLR male leads for the last stretch from the Art units to the mixer.

The only reason I'm considering the Orchid dual channel boxes is that they have a good reputation and a low price. More so it seems than the Art T8 of which I get the internet vibe of "good enough for live use".

The other impression I'm getting is that from a cost perspective, a good transformer is more expensive than the parts needed for a no-thrills active DI such as the Orchid. So from that point of view I'm also expecting less from the Art T8.

But maybe I'm overthinking this and the Art T8 is just good enough? Even if the Orchid DI sounds better, I might not hear it...

[James Perrett]

Have you tried talking to the people at Orchid? They may well be able to make up exactly what you want in a single box.

[jvq]

Thanks James, that was a good suggestion. I have reached out to Orchid Electronics and they are being very helpful and responsive.

[Hugh Robjohns]

I don't like the arrangement of inputs / outputs on the 8-channel Orchid passive rack DI, at €35 per channel. The unit also appears to be twice as deep as the Art. It would be awkward to have cables poking out both ways. Something like the Radial Pro-D8 has the same size / orientation problem....

The normal configuration for multichannel rack DI boxes is to have the instrument inputs and link outputs on the front, and the balanced mic-level outputs at the rear -- these normally being permanently wired in a mixer rack or connected via a loom or snake, so easy access to those connectors isn't usually that important and so it makes sense to stick them around the back.

However, John at Orchid will do custom builds so if you want all the socketry at the front I'm sure he could accommodate your requirements.

The only reason I'm considering the Orchid dual channel boxes is that they have a good reputation and a low price. More so it seems than the Art T8 of which I get the internet vibe of "good enough for live use".

The technical performance of a passive DI/isolator, like the T8, is governed by the quality of the transformer. Those employed in the T8 are actually remarkably good for the money, but it's true that they're not in the same league as the best Jensens, Lundahls or Sowters. But then you're talking of £28 per channel and not £70+ per channel....

The difference is basically a slightly greater level of harmonic distortion, although few would ever notice or care. The real difference is less ability to cope with very high levels of deep bass -- or in other words, a very high quality transformer can pass higher levels of bass with a little less distortion. And if LF harmonic distortion does become an issue, just back the level off a bit...

But maybe I'm overthinking this and the Art T8 is just good enough? Even if the Orchid DI sounds better, I might not hear it...

Unless you are extremely picky I'd say the T8 is, indeed, good enough for 90% of applications... but the Orchid active DI does definitely sound more transparent. So whereas you might be aware that the T8 is in the signal path, you won't notice the Orchid, and for home studio applications I'd definitely go with the active Orchid solution in one form or another.

For live stage use, though, I'd be more tempted to go with a transformer-based isolator/DI box, just to provide an extra degree of electrical isolation and protection from the house PA system.

Just as an alternative idea to the centralised rack-mount multichannel DI box idea, you could consider purchasing a number of Orchid micro-DI's, and fix them next to or on the back of your individual keyboards, and then run standard XLR cables from there to your console. I do that sometimes with my keyboard setups and it works very nicely.

H

[jvq]

Thanks Hugh!

When I put the question (active transformerless DI vs passive transformer iso) to John at Orchid Electronics he suggested that transformers would be better for my use case. He also offered to build them into a more convenient custom 8-channel box for me, at a price that beats the ART T8. Needless to say I ordered 2x 8 channels from Orchid in a heartbeat.

Good to know that the likeliest source of trouble is the low end. I do have some sound sources which can be unruly there, which is one of the main reasons I want a digital mixer with sweepable HPF and good parametric EQ. They all have volume control so I can back them off if I have to, and re-amplify with the mixer pre-amps.

I may also still go the way of putting the iso boxes closer to the source; with the way my studio is laid out I could deploy one of them as a sort of stage box. That would save space on my desk behind the mixer. But at first I should be able to leave all my cables in place and just swap out my old MixWizard for the new mixer and the two 8-channel iso boxes.

[Hugh Robjohns]

Needless to say I ordered 2x 8 channels from Orchid in a heartbeat.

Fair enough. There won't be much in the sound either way, but going with transformer isolation is the safest solution without doubt.

H