Limiter (hardware) for recording purposes

[cptgone]

DAW user here, caught between my desire to keep everything in the box, and the desire to add something 'organic' to my music (be it guitar or vocals).

I've been spending a lot of time playing guitar lately, I even built a huge pedal board.
My chain:

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[acoustic] guitar [or vocals] => [pedalboard] => Focusrite audio interface with preamps

No amp (except perhaps an amp sim, to be added after the recording).

To avoid distorted peaks while recording, I'm considering adding a hardware brickwall limiter (or even a clipper, if that would work).
I'm not really looking for compression (I'd prefer to do that in the box, afterwards, to avoid overdoing it permanently).

A little research seems to show that most pedals aren't meant for such taming of peaks (they seem to be aimed at compression mainly, and not meant for DI recording, but usage with an amp).

Some options I found:
- EHX Platform compressor (a pedal that is claimed by its makers to be studio worthy)
- Keeley GC-2 Guitarist Limiting Amplifier (boutique pedal)
- FMR Audio RNLA 7239

Any ideas? How do you guys cope with peaks while recording?

[Aloysius]

Record at a suitable volume.

Control your voice and your playing naturally.

[kvaca]

How do you guys cope with peaks while recording?

AFAIK there are no brickwall hw limiters, only clippers or fast compressors,
but theres no need for limiter, just keep the gain as low as needed...
or - if youve got enough money - use bomber
https://burlaudio.com/products/b2-bomber-adc

[cptgone]

AFAIK there are no brickwall hw limiters, only clippers or fast compressors,
but theres no need for limiter, just keep the gain as low as needed...

Record at a suitable volume.

Control your voice and your playing naturally.

Easier said than done (esp. with all the effect pedals - and I'm planning to record both dry and treated signal, which makes it even harder to avoid bad peaks).
Moreover, I end up recording too silently that way, which makes me worried about the actual resolution of my recording.

[Jafo]

Google "gain staging."

Record at a higher bit depth. 24 bits allows you to hit 144 dB. You aren't Pete Townshend, perchance?

<b>Then</b> ask about a hardware solution. Unless you're shilling for a hardware company, of course.

[JCJR]

Tis hard to do transparent limiting without lookahead. There are some lookahead hardware limiters but most do not do that. HiFi lookahead limiter needs HiFi delay line which is no big deal nowadays but in the past just a HiFi digital delay line could cost thousands of dollars so not many analog lookahead limiters were made and sold before computer software lookahead limiters became the thang starting in the 1980's.

Without lookahead a limiter has to respond so drastically fast to over peaks that it has no choice but to clip the leading edge of such peaks. Such clipping can sound like distortion or intermittent clicks in the music.

Say if you hit a real loud note then the limiter compressor can lower the gain and be clean on everything except the peak leading edge. Quickly lowering the gain on the peak leading edge is the same thing as clipping the first leading edge halfwave. For some reason maybe Murphy's law, even if most such brief clips might be inaudible some of them will sound to the ear like nasty clicks which can ruin a track even if there are only a few of them.

In the Stone age were a few rare ultra expensive analog lookahead mastering limiters. Waves has made a couple models of hardware lookahead limiter that are expensive but not outrageously ridiculously expensive and maybe you could find one used.

I'm pulling a blank on the company name, that Scandinavian company that makes so many nice FX boxes-- They have sold several versions of "auto mastering" digital rackmounts over the years which purportedly have a nice enough limiter as one of the tools.

Behringer made somewhat clones of those automastering boxes.

Dbx, behringer and others make digital speaker processor boxes which include limiters in the toolkit. I have a Dbx driverack speaker processor I like a lot for the home studio monitor system but only barely tested the limiter a few minutes many years ago.

Maybe the limiters in speaker processors can be transparent but I wouldn't bet on it without a test because those limiters are included mainly to keep from blowing up concert speaker stacks. They don't put em in there necessarily for clean transparent sound.

Which is the same deal as the old vintage non lookahead analog limiters of yesteryear. They were more to avoid blowing speakers than for sounding pretty.

[cptgone]

@Jafo: thanks, I'll read up on gain staging.
24 bit may be the solution, but my PC has trouble coping with resource consumption peaks. I'll give it another try.

@JCJR: thank you very much for your very informative post. You made things much clearer for me.
The Scandinavian company that was on the tip of your tongue is prolly TC Electronics (love their pedals). I'll have a look at (that and) the cheaper Behringer options.

[vurt]

i have the platform.
although i tend to use it at the start of the chain to level stuff before the fx, when i first got my vfx klein bottle, due to the mental feedback loops the platform did spend a time as an end if chain limiter (it has a limiter mode)and worked well enough.
it's also very transparent, not to mention the overdrive is lovely and the swell sounds nice if you did decide to use it earlier in the chain at any point.

[cptgone]

@ vurt: thanks for your helpful feedback.
Speaking of which, that VFE Klein Bottle pedal looks like a monster

[BertKoor]

My chain:
[code
[acoustic] guitar [or vocals] => [pedalboard] => Focusrite audio interface with preamps
[/code]

Damnit, I thought you were going to share the whole pedal board chain. This here (source -> effects -> interface) goes without saying.

I think you think you need to record loud. That's a mistake...
Example: you record in 16bits. Add two such tracks, and the result is actually 17 bits. Add four and the result is 18 bits. Summing eight tracks results in 19 bits, sixteen tracks: 20 bits.
Since not all tracks will peak at the same time, you might get away with 18 bits.

Anyway, in the end result of a 16 bit cd just 14 of the original 16 bits you recorded are used. So you can record 12dB softer than totally maxxing out your practical dynamical range without affecting the outcome at all.

But your interface can do more than 16 bits. Doing so will double the size of stored recordings (24bit is often stored in 4 bytes.) Modern hard disks can keep up with that easily. And to the DAW processing it makes no difference at all. First thing it does with a 16 bit recording is make it 32bit floating point, since that is the native audio data format for VST.

So if your recordings have an average (VU, RMS) level of -22 to -18dBfs that's optimal. This is the sort of level your preamps an AD converters are built for. Plenty of headroom, no limiter required.

Ok, but you have these pedals, and some will boost the signal considerately. Well, be prepared for that. Turn the trim down. Or turn down volume on the pedal. It might even be less noisy at lower volume.
Are you switching that boosting pedal on & off during the take? Maybe better not and split the take. It requires different handling anyway.

[cptgone]

I think you think you need to record loud. That's a mistake...

Indeed I was (I started out in the analog era, my first DAW consisted of 2 portable tape recorders with built-in mic )

Turn the trim down. Or turn down volume on the pedal. It might even be less noisy at lower volume.

Ah, that's good to know, wouldn't have suspected that.

Are you switching that boosting pedal on & off during the take? Maybe better not and split the take. It requires different handling anyway.

Another tip to keep in mind. Thanks!

Damnit, I thought you were going to share the whole pedal board chain. This here (source -> effects -> interface) goes without saying.

It's a work in progress, apart from the 10-ish pedals that are yet to be delivered over the next few months I now have over 20 (mostly cheap) pedals with most bases covered (whammy, freqout, wah, overdrive, fuzz, distortion, modulation, delay). Delay feedback can quickly get out of hand...

Thank you very much indeed

[vurt]

@ vurt: thanks for your helpful feedback.
Speaking of which, that VFE Klein Bottle pedal looks like a monster

no probs, although i would agree with bertkoor, for the majority of things proper gain staging is much better than a limiter on recordings imo.
like i said, only pulled it in to use for the kb, which is indeed a monster.
you think your delay gets out of hand? imagine 3 delays in feedback loops
so yeah, limiter for my ears and speakers sake while i found the manageable sounds.

sadly i think the guy stopped making them but im sure they'll pop up here n there, hopefully not at massively inflated prices.
but if you are interested, check out the knobs channel video for it on youtube.
i saw that and was "instabuy"

[ShawnG]

https://www.google.com/shopping/product ... oC5bPw_wcB

Here's what I have used for that purpose. makes a decent preamp for bass and guitar, adds a bit of tube warmth for mics, is cheap and has an OPl button which tames the output. ART calls it an output protection limiter, but as for the reasons mentioned above it is not a true limiter in the strictest sense of the word, but it's probably kinda what you're looking for? They have a v3 version of this that is blue and has a settings knob for the "limiter" rather than a simple on/off button, but its a hundred bucks, this is fifty.

it's got a tube, and its not meant to be transparent, so if clinical cleanness or audiophile snobbery is what you're after, this ain't it.

[JCJR]

BertKoor covers the territory well.

Let's say you have a nice squeaky clean solid state line level analog device whose nominal 0 db operating level is +4 dBu (a sine at about 1.736 volts peak). If such a device can go clean up to 12 volts peak then the max clean output would be about 20 * log10(12 / 1.736) = about +16.8 dB louder than the nominal operating level, or (16.8 + 4) = 20.8 dBu max clean output level.

To somewhat emulate that ballpark of analog headroom, in digital-- Maybe because audio folk were already accustomed to working thataway-- Because 0 dB digital is as loud as digital can be clean, the usual nominal digital operating level tends to be around -18 dB for a similar headroom as analog, above nominal operating level.

This is not necessarily the case with audio processing after it is in the computer (opinions vary and I sometimes like to use somewhat hotter levels once in the digital domain). Also final mixes for distribution are sometimes boosted stupid loud close to 0 dB.

But at least for initial recording from the real world, if you set the nominal level around -18 dB or maybe sometimes even lower for very unruly sources, then it is usually enough headroom to avoid clipping.

[JCJR]

Maybe a simple old style non lookahead analog limiter wouldn't be so bad if one were recording around -18 dB and the only reason for the limiter is in case a track gets so out of hand that even 18dB is not enough headroom to avoid clipping. In that case you are expecting the limiter to never get hit at all, but in the unlikely case things go real weird maybe the limiter would sound better than digital clipping.

On the topic of lookahead hardware digital limiters-- They do have their uses but basically it just pushes back the proper level-setting by a layer. You have to set the input gain on the hardware digital limiter so it doesn't clip the digital audio in the hardware box, so if set wrong it offers no extra protection than just using conservative record levels direct into the computer.

For instance a lot of digital line level boxes like my dbx driverack have nominal level at +4 dBu and will go clean up to +20 dBu or higher. So basically if you feed the box what it expects (+4 dBu) then it is probably processing at about -18 dB below it's max digital resolution. If you feed it too hot a signal then it will probably clip the output. Just like a strictly analog device with similar specs.

Maybe one way to somewhat help keep gains in control if you are mostly using +4 dBu analog gear (mixers and rack boxes)-- You could set the gain on your audio interface input so that it requires maybe +20 dBu analog input to record up to 0 dB digital peak in the computer.

Maybe that would make it simpler because in that case your outboard analog gear will clip at about the same level as your digital audio inputs. So if you are accustomed to avoiding clipping in the analog gear, then it automatically also avoids clipping in the digital gear. At least somewhat.