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HPF Suggestions

@Kurt Foster @audiokid @Boswell @dvdhawk @kmetal @pcrecord, @Davedog, @paulears,
@bouldersound , et al'
Hi guys.... :)
I'm tracking an acoustic guitar today, it's a driving part, heavy strumming (think Bob Seger's "Night Moves" style).
I want to try using a newer AKG 414/XLS model. The mic has 3 HPF selections; 40, 80, and 160hz. Im assuming the slope is -12 ( I could be wrong about that, it might be -6 but at that point it would be more of a shelf than an actual HPF? I'm not as familiar with the newer 414 models )...
The space is treated ( it's the same space I mix in).
Which HP would you opt for on the mic, and/or would you choose to use an HPF on the channel input instead at a different value? I have a software based input mixer that has a variable HPF...
Thoughts?

Comments

Profile picture for user Davedog

Davedog Wed, 09/06/2017 - 07:31

It would actually depend on the characteristics of the guitars response to being "driven". My feeling on this kind of part is it all begins with the pick attack. What weight of pick would you be using to play this kind of part?

I have a huge collection of picks. All shapes,sizes,materials, weights,etc.....If you listen hard to the track mentioned (ie:Night Moves) you can hear the pick 'flipping' with the strum...which to me says light bendable plastic.

I use a large triangular pick in light gauge for something like this. It is a Tortex pick. So while it isn't something you can really dig into the strings with, it does keep its shape and a driving constant rhythm type of playing seems to keep the extreme low-end out of the box. Plus you get the percussive attack to emphasize the strum.

As for the HPF, I would set the mic @ 80hz to start and you probably wont need to move it unless your box is bassy. Once I get the mic's response to sit nice then and only then would I look at the channel HPF and only if needed. The voice of the mic will be the most important part of this capture. But before that its all about the amount of response from the box and how the strum is being approached.

I also have a big pick made of stainless spring steel. It's very flexible and imparts a curious strum sound that nothing else will even get close to. I can't confirm this but I can hear this sound on earlier Stones songs and it always made me wonder if Keef wasn't using a steel pick.....think Angie...

Profile picture for user DonnyThompson

DonnyThompson Wed, 09/06/2017 - 07:39

@Davedog
I hadn't even considered what you mentioned about picks, Dave. But it's certainly pertinent. I mostly use Fender Mediums, in fact I'm not sure I even have any other types of picks laying around here. I've just used them for so long now that they've become my go-to.
Also, I'm using a lighter gauge of strings, I think I've got 11's on my Washburn right now, although I know I've got at least one new set of 12's here somewhere.
Good suggestions Dave.
Thanks!

Profile picture for user Davedog

Davedog Wed, 09/06/2017 - 07:48

I record a lot of acoustic guitars. Pick attack is the most overlooked item of the list of 'shite to check on'......I recorded a fantastic finger picker once who had cultured his nails in order to get that sound he was looking for. As we moved through his repertoire I noticed a faint but definite "click" on the tracks. Turns out he was keeping time with his pinky by tapping it on the guitar top. He had done it for so long live that it wasn't really noticeable. It was CERTAINLY noticeable when he'd get a touch out of time. As we all know...In the studio, "Mic Don't Lie"

Profile picture for user Boswell

Boswell Wed, 09/06/2017 - 07:58

DonnyThompson, post: 452536, member: 46114 wrote: I want to try using a newer AKG 414/XLS model. The mic has 3 HPF selections; 40, 80, and 160hz. Im assuming the slope is -12 ( I could be wrong about that, it might be -6 but at that point it would be more of a shelf than an actual HPF? I'm not as familiar with the newer 414 models ).

This is the curve for the C414-XLS, showing the switchable HPF characteristics.


I've always mentally taken these HPF settings as being "instrument/male voice/female voice", with the no HPF setting being for piano, church organ or anything else that needs response to go below 50Hz.

The interesting thing is that the 160Hz cut is 6dB/octave, where the other two are 12dB/octave.

For acoustic guitar that has to sit in a mix with bass and drumkit, my instinct would be to track with the HPF set to 80Hz, and then sculpt further in the mix if need be.

Profile picture for user kmetal

kmetal Wed, 09/06/2017 - 08:04

That's the model 414 I have. 80hz is what I use on acoustic in general. Unless it was an exceptionally thin guitar, or solo acoustic performance, which I'd use none at all, or the 40hz.

80hz is the one I used most on acoustic by far.

Profile picture for user kmetal

kmetal Wed, 09/06/2017 - 08:10

Davedog, post: 452545, member: 4495 wrote: I record a lot of acoustic guitars. Pick attack is the most overlooked item of the list of 'shite to check on'......I recorded a fantastic finger picker once who had cultured his nails in order to get that sound he was looking for. As we moved through his repertoire I noticed a faint but definite "click" on the tracks. Turns out he was keeping time with his pinky by tapping it on the guitar top. He had done it for so long live that it wasn't really noticeable. It was CERTAINLY noticeable when he'd get a touch out of time. As we all know...In the studio, "Mic Don't Lie"

That's funny to me becuase pick attack is one of the main things I focus on beyond general tone and tuning. Pick attack is often the only sound you hear on a modern pop acoustic guitar in the mix. Usually it's a Taylor sounding guitar with a treble boost, and HPF, at least sonically to my ears anyway.

I had the same thing with 'tapping for time' with a bassist who primarily played live. On the recording he kept tapping his bass in between pauses and breaks in the tune. We broke this habit in the studio.

Profile picture for user dvdhawk

dvdhawk Wed, 09/06/2017 - 08:33

The slope is 12 dB/octave at the 40Hz and 80Hz settings, but only 6dB/octave at the 160Hz setting.

Interestingly, the instructional part of the current English version of the C414XLS manual only mentions that it's 6dB @160Hz and completely omits the 40&80Hz info. However, you don't need a degree in German to translate "12 dB/Oktave bei den Eckfrequenzen 40 Hz und 80 Hz sowie 6 dB/Oktave bei der Eckfrequenz 160 Hz" from the German section, which is first in the manual. The English Tech Spec section does include the complete spec.

And none of them would result in a shelf, they keep attenuating xdB for the subesquent octaves until they hit - infinity. It's just a matter of how steep is the slope. "Slope" being one of those technical terms that means exactly what it says.

Anyway, having cleared that up, I feel like we've talked about this here before. ( Noteably, Boswell's comments about unintended filters and phasing when those slopes overlap or collide.) @Boswell will surely correct me if I'm wrong, but I don't think those filter/phasing issues occur, if for instance you record the acoustic with only a 40Hz HPF at the mic, and then dial in another HPF freq on that track at mixdown. My guess would be that bad phase stuff only happens when you've got multiple filters affecting the same signal going in and that once one pure filter is printed to "tape" the interaction doesn't happen when a second filter is applied to the recorded sound.

Bottom line, unless I was concerned the acoustic was going to overload the mic with some rogue bass frequencies, (or if there's a drummer bleeding in from an adjacent room) I'd be inclined to track it flat and leave myself as much, or as little, low-end as is appropriate at mix time. At mix time you may well roll-off below 160Hz (if the bass player is any good). Sometimes you just want the "jangly" part of the acoustic in the mix, sometimes it needs more body. Why handcuff yourself?

Profile picture for user kmetal

kmetal Wed, 09/06/2017 - 09:15

Certain mics also change/degrade in timbre to a noticeable degree, when the filters are engaged, beyond what the filters job is, so it's not always a pure technical choice. The XLS has doesn't exhibit this problem to my ears.

Also it should be noted there are two different XLS versions, one with a painted logo (pre Harmon) and one with a blue logo (post Harmon). I don't know what, if any, other differences are there but the pre Harmon ones were manufactured and tested completely in Austria, where the post Harmon its a bit unclear. You'll notice on the akg 240 headphones pre Harmon ones say made in Austria, the post say made in china. Since both reflect a drop in price tag after Harmon acquisition, I am suspect. One place where a manufacturer could slyly cut corners or increase tolerances would be the filters and swtiches.

I don't know this from fact or experience, but I do know the pre Harmon xls retailed for 1,099, and the post Harmon for 899.

Profile picture for user DonnyThompson

DonnyThompson Wed, 09/06/2017 - 09:22

dvdhawk, post: 452549, member: 36047 wrote: if the bass player is any good). Sometimes you just want the "jangly" part of the acoustic in the mix, sometimes it needs more body. Why handcuff yourself?

Well, the bass player was exceptional .. it so happens that the bass player was you. ;)
I'm looking at thickening up - or adding to - the acoustic DI track we did this past weekend with Scottie Stiert. I thought perhaps I would double his acoustic track, using one of your 414XLS mics. I'm not changing the performance, I'm simply doubling the chords that he played. The song relies a lot on the acoustic "drive", and the DI from his built in pickup is just a bit too thin sounding to have it be prominent.
BTW - all the other tracks sounded great in the first initial static mix I called up yesterday- and your bass track was indeed awesome. The only weak spot in the initial mix is Scott's guitar tone, although his playing was great.

Profile picture for user dvdhawk

dvdhawk Wed, 09/06/2017 - 12:00

Well, in the interest of full disclosure (so our friends and colleagues here don't get the impression your co-engineer was too lazy to mic up the acoustic) the DI track was only meant to augment the vintage 414 we used as the primary source for the guitar. Your EB around the 12th fret sounded beautiful and didn't need much help from the DI. The vocal and acoustic are really the centerpiece of the song, and given Scott's free-flowing style we made the deliberate decision to track the live band simultaneously with the live vocal mic and guitar mic to preserve the feel - at the expense of more bleed and knowing we'd need a great take from everybody in the same pass to get a 'keeper.' Of course we could have punched-in minor fixes for the DI'ed bass (Avalon U5) and keys (that's right, Kyle, call the cops! ... a Rapco stereo DI), and probably the fairly isolated electric guitar (SM57 & MXL 860 ribbon), but still needed a good feeling take from everyone. Scott's song was perfectly suited to his voice, and his tone was consistently great from the start of the session to the end, but his phrasing and melody were very fluid and freestyle which varied significantly from one take to the next. So I'm convinced tracking everyone together was the best approach to capture the natural feel of the song.

As you will recall, this relatively lackluster DI issue only arose because as we were tracking the vocal (SM7B) and Taylor acoustic (414EB + Countryman Type 85) some dude's outboard pre-amp started making staticky noises on the SM7 vocal track, rendering both of those mic'ed tracks on that otherwise flawless take unusable due to the unavoidable bleed between the two. *[Programming Note; Stay tuned for a thread called, Hey Bos, why do you suppose my pre-amp is making this noise?] We already had another flawless, noise-free, 100% live, 'keeper' take, so we thought we'd have him take a shot at overdubbing the vocal track over the noisy 'keeper' take just to see what he could do vocally without the distraction of playing guitar. Since everyone's performance was solid on the noise-free 'keeper' we had nothing to lose. There's no question that when we eliminated the mic-bleed factor of his guitar, by doing tracking a separate vocal track, that allowed us to swap out the SM7 in favor of the 414, and Scott's voice really shined on the overdub through the EB, (and a non-noisy pre). And the pickup/DI alone couldn't compare to the 414EB+DI combination, especially in the spots where it's just guitar and vocal. Net result though, the noisy pre-amp gave us a good reason to track his vocal separately, and once he got settled in to singing without a guitar as an extension of his body, we got some amazing vocal performances to choose from.

In the gaps where it's just guitar and no vocal you can use Scott's 414EB track, and then double just where it coincides with the vocal. The offending noise isn't on Scott's acoustic mic, it's just the bleed into it that won't match the overdubbed vocal that is the issue.

Profile picture for user kmetal

kmetal Wed, 09/06/2017 - 14:21

dvdhawk, post: 452559, member: 36047 wrote: Of course we could have punched-in minor fixes for the DI'ed bass (Avalon U5) and keys (that's right, Kyle, call the cops! ... a Rapco stereo DI),

I prefer to run from the cops...

Profile picture for user dvdhawk

dvdhawk Wed, 09/06/2017 - 15:27

kmetal, post: 452551, member: 37533 wrote: the pre Harmon ones were manufactured and tested completely in Austria, where the post Harmon its a bit unclear.

You're right, they're shaving off costs somewhere. Harman acquired AKG in '94 and the good stuff continued to be made in Austria (for the most part) until fairly recently. I can't be any more specific about what they've done in the last 5 years or so. I used to sell a lot of their wireless systems and stopped handling them once everything was cheap plastic. And now I'm sure they can still say many things are still "Made in Austria", with the only difference being, they're made in Austria using parts made way, way, waaaaaay east of Austria.

Profile picture for user kmetal

kmetal Wed, 09/06/2017 - 15:42

dvdhawk, post: 452574, member: 36047 wrote: You're right, they're shaving off costs somewhere. Harman acquired AKG in '94 and the good stuff continued to be made in Austria (for the most part) until fairly recently. I can't be any more specific about what they've done in the last 5 years or so. I used to sell a lot of their wireless systems and stopped handling them once everything was cheap plastic. And now I'm sure they can still say many things are still "Made in Austria", with the only difference being, they're made in Austria using parts made way, way, waaaaaay east of Austria.

Oh wow that's good info Dave. I was wrong in my thinking about when they were acquired by Harmon. My AKG stuff is from around '05, so I'm incorrect about the painted logo thing on the XLS deaming it "pre Harmon". I only noticed a difference (Harmon involvement) when they switched to the current made in China 240's and the blue logo on the XLS mics, as well as the addition of the 214/314 models.

If you take the ULS 414 there is a couple less pickup patterns, (features..) and a non-led, physically positioned, switch for the HPF and pickup patterns. (Instead of the led indicated, push button selector on the xls) Don't know what the technical name for those is. Their darker sounding as well, compared to the xls, at least the ones I've used.

That said I still think the xls, at least the painted logo one I've used, is a good mic, and prefer its brightness over the uls. And could only dream of the silky nirvana of the EB. I've always found any 414 to be solid, but not magical or with a lot of mojo. Just nice on most things. I call it the sm57 of condensers. Not always the best, but rarely a bad choice. I belive the EB is the Mojo mic model.

It seems perhaps brighter comes with cheaper? And certainly more features seem come with lesser quality or cheapening of things.

I'm sorta begrudgingly selling my xls but was touting it pre Harmon, I'm gonna have to check and see if it says made in Austria on it.

Thanks for the clarification.

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