LinuxMusicians

Hello!

I need to change my old setting and I'm seeking advice regarding hardware (computer & audio interface). I haven't yet managed to reach a deciding state with the answers I could find on the forum, and as I think my situation my actually be quite common, I thought it could be useful to describe it and gather your answers here.

I'm happy to see that linux now is more than ready for audio production It was not the case (for me at least) when I bought my previous gear, more than 12 years ago. I seek to update my system, buying a desktop computer and an audio interface, dedicated to music (using AVLinux). Here is the foreseen use:

_ recording (reaper) with a reasonable amount of tracks (most likely at most 5 + a parent drum track); so there will be some plugins running but not an incredible amount;

_ guitar practicing : need to hear me in 'real time' (low latency) and with a couple of plugins if possible to get a decent enough sound (even if not super fancy); so far I've been using a toneport on my old 2008 mackbook and it was doing this just fine (toneport works out of the box nowadays on linux (say avlinux), but you can't use this line6 'tonedirect monitoring' which is part of gearbox/podfarm, and the connexion is usb 1.1 so I get too much latency or too many cracks if I use plugins :-/ )

I won't really mix/master (other than for personal use/small diffusion).

Any advice on the computer spec (cpu/ram/motherboard/hardrive) would be nice (I'm completely out of the current standards!).
I'll put a firewire PCI card (I have an external firewire HDD), so any advice on the chipset for linux compatibility is welcome.

This also means that I do not mind a firewire audio interface (actually, I tend to like it because it saves some cpu cycles compared to usb, but that may be irrelevant nowadays, and maybe I can get a good cheap second hand option).

To keep talking about the audio interface, I'd like at least 2 inputs (XLR & instrument, I'll be recording from jack at instrument level, from XLR microphone & out of a DI box with XLR cable), and midi IN/OUT (old school) could be good (I plan a small keyboard extension). A line in could be useful (and is usually there anyways I believe).
I've seen things like Berhinger U-Phoria UMC404HD although it seems they're usb only now (well, if it works well enough I don't insist on firewire but I'd like to keep latency under heavy control!), but again I'm at loss here.
I guess a PCI-E card with external pre-amps converters is a whole different budget (and I don't have a feedback regarding compatibility with (av)linux).
So here again, any help is welcome.

I apologise for this long post. I believe there might be a number of people wanting to build up a practicing/recording desktop under linux, in particular with instruments like (bass) guitars/microphones/midi keybards, so I think it might useful to others too.

Many thanks!

For your use (5 tracks in reaper with some plugins) even a raspi 3 would be enough. The built-in plugs are very efficient. If you miss something, take a look at the JS section as well.

For your guitar practicing: i use this sim: https://audio-assault.com/reampstudio.php on a Thinkpad T520 and a Behringer UMC204 (so not a lot of power). I can comfortably play at ~5ms without any xruns, or ~2ms with a few xruns every ~20-30 secs.
That said, there are good sounding outboard sims, too. I borrowed a 1. gen tech21 flyrig, it was really good for jcm800 sounds.

Hi,

Thanks for jumping in & providing info!

I meant 5 + all drum tracks, but it still means that I'm quite free as for the cpu choice: I probably can be a few generations late from the current rage, that's good. (By the way, in case I have a choice, is a higher number of cores useful for music or should less cores with more power each be more comfortable? Just ignore if not relevant.)

I had not thought of an external sim, but maybe it's a good idea, depending on what I can find.

Regarding latency, say with guitarix for now, any feedback on firewire vs usb2 versions of some interfaces?

And yes, the stock plugins in reaper do get you a long way, they're excellent!

Thanks!

I don't agree with the recommendations on USB audio interfaces for monitoring electric guitar direct on Linux. Admittedly, I have no experience of the few units that apparently have some sort of Linux drivers written for them, but with the generic USB audio interface driver (snd-usb-audio) there is a a lot of extra latency being added that's NOT reported by tools like QJackctl or Cadence. To get an idea how much latency is being added, you need to measure the extra roundtrip latency yourself via different means to find out the correct values - and the value for roundtrip latency is closer to what you are going to get when playing an electric guitar with an amp sim and effects anyway.

I've used RME Babyface Pro and a Yamaha mixer with a built-in USB interface on Linux and I haven't been happy at all. At 128 frames 2 periods the latency has been still in the 12-15 ms region (acceptable, although hardly optimal for faster runs). However, USB tends to work better with 3 buffers, and at 128/3 those two interfaces have had the roundtrip latency of 18-20ms. That's not acceptable for playing electric guitar, especially when using clean sounds. For that matter, with larger multitrack productions you'll need to increase the frame / buffer rates anyway, so that'll introduce more trouble when overdubbing.

more info:
https://www.alsa-project.org/pipermail/ ... 41201.html
https://forum.cockos.com/showthread.php?t=209729
(unfortunately, the fix mentioned above hasn't been made publicly available by any of the main distros AFAIK).

If these problems have been corrected with recent kernel changes (etc.), please correct me on this issue.

I got myself a second-hand RME HDSPe AIO PCIe card about a year ago and everything works well. It got to a point with the USB interfaces that I thought my playing technique was getting ruined due to the extra latency - I was constantly off with my timing. Playing an electric guitar with a real amp or an acoustic guitar felt just plain weird when the latency wasn't there.

With MIDI keyboards and sofsynths there are fewer noticeable issues with USB, although they are there and may bother some.

Hi,

Many thanks WforWoollyMammoth, that's a very useful input. I'll dig more but it probably means I need to reassess my views for practicing.
(I haven't made a measurement, but reaper does not give me a worse latency than what you wrote with my USB 1.1 Toneport…) I can definitely hear what you say about spoiling your timing. You'll get a little ahead when playing in 'normal' situations, where you'd need to be spot on for instance.

Do you know if things get better with a firewire interface? RME is out of my budget here.

For practicing, my aim was to avoid using my custom 15W / 5W all tube head on a daily basis. I like it a lot but it feels like a waste to run it at low volume every day. Based on what you say, maybe I would be better off getting a small (transistor) practice amp with a headphone (or line) out, and plug this into my toneport.

Anybody willing to share his workflow/solutions here?
[A two-notes torpedo something could be very useful for recording, but: quite a budget ; probably not useful under linux ; doesn't solve the waste feeling regarding practicing…]

erena wrote: ↑Mon Nov 23, 2020 7:46 am Hi,

Many thanks WforWoollyMammoth, that's a very useful input. I'll dig more but it probably means I need to reassess my views for practicing.
(I haven't made a measurement, but reaper does not give me a worse latency than what you wrote with my USB 1.1 Toneport…) I can definitely hear what you say about spoiling your timing. You'll get a little ahead when playing in 'normal' situations, where you'd need to be spot on for instance.

Do you know if things get better with a firewire interface? RME is out of my budget here.

For practicing, my aim was to avoid using my custom 15W / 5W all tube head on a daily basis. I like it a lot but it feels like a waste to run it at low volume every day. Based on what you say, maybe I would be better off getting a small (transistor) practice amp with a headphone (or line) out, and plug this into my toneport.

Anybody willing to share his workflow/solutions here?
[A two-notes torpedo something could be very useful for recording, but: quite a budget ; probably not useful under linux ; doesn't solve the waste feeling regarding practicing…]

Firewire interfaces were used for years on Linux and people were happy with them, as far as I can recall. These days they require an adapter with the available motherboards and, in all honesty, I had trouble figuring out what type of adapters actually work with Linux, so I gave up on the idea of going that route myself (and just got the RME PCIe card). I hope I'm not talking out of my a-- here, but I think several individuals that are actively developing stuff for Linux, and are guitarists themselves, are still using Firewire. Firewire should be an option, at least.

For the price of the RME card I've bought up, you should be able to get something like a Boss Katana, right? Many amp heads have a simulated output these days (I've actually never owned one that doesn't have a simulated output and the simulations are far better than in the past). Shouldn't be too hard to find something suitable from the 2nd hand market.

I should emphasize that with USB interfaces you CAN get good enough latency for practicing with software amp suites like Guitarix (or the commercial products by Audio Assault), but when it's time to record the guitars on your multitrack productions, you really can't keep the settings that way and have to increase the frame rate and buffers. The problem in practical terms with latency on Linux is that it goes from "this is okay" to "this is absolutely terrible" really quickly due to that additional buffer introduced by the ALSA USB driver. The difference on WIN / macOS is nowhere nearly as bad.