Gain Staging: The everlasting quest for "reasonable" acoustic tone.

[funkymonk#9]

I thought my acoustic amplified tone was getting better but did a Tascam stereo mic recording of (full band) and the guitar sounded dry. (of course my eq skills are hit and miss at best). Wondering about gain staging as I put the pieces together correctly in the chain.

Acoustic guitar with McIntyre Feather or Seymour Duncan bargain soundhole pickup.

Run into a Rane Ap-13: it has an input in front as well as a piezo input in the rear.
Rane Balanced XLR output to Soundcraft Mixer XLR Input
Soundcraft Balanced XLR output to Hafler 3000 Balanced XLR Input
Hafler 3000 to Daedalus W803.

1. I need to know the gains of each to get the cleanest headroom available.
And 2. If I need a little more boost or reduction, which should I take it from.

My tightrope is that I like clarity but when when it gets to raw like fingernails on a chalk board I would rather sound like a jazz guitar with all the highs rolled off. Looking for the sweet spot, but for now just the gain staging and save the eq tips for next time.

Thanks in advance if you know my gear and can tips for amplified acoustic bliss!!! Feel free to tell me I need more or less gear too, lol.

[stevecuss]

Hmmm, this is a tough one, because you're describing the guitar as 'dry' and saying you don't like the tone, but don't want to talk EQ at this time and want to address gain staging, but iff my guitar was dry and I didn't care for the tone, I would 'wet' it up with a touch of reverb and rolled off highs and I would pay very careful attention to the EQ spectrum and try to slice out any peaks.

Would you provide some specific info?

-- What guitar?

-- How would you describe the difference between your natural guitar tone and the tone you're hearing from the recording?

-- is the guitar 'distorting' or showing any red levels at the soundboard?

All things being equal, I'd gain it most at the Rane and least at the board.

[funkymonk#9]

Ok, I am not opposed to talking EQ, I wanted to make sure that the gain at different points wasn't effecting the tone I was experiencing.
I do have some reverb options in the mixer fx.
It's possible I also am not sure how the Rane: Trim, Output slider and Level Slider work in conjunction.

I have a '76 Guild D-40C, the natural tone sounds dry but sweet, the amplified tone starts to sound crispy, perhaps that mid-high quack.
Also for some reason I do not get levels on the mixer, unsure why, i have looked at the manual but see no reason why I get no sound levels. But there is no distortion.

[M Hayden]

Remember that the Rane input on the front panel is stereo, so you might want to use a stereo male to dual mono female cord to ensure you’re feeding the channel you are intending to feed. I do that and plug a Bartolini-equipped jazz box into the second channel and a passive PUTW-equipped acoustic into the first, and set levels and EQ separately.

Rick Turner has said he tries to ensure the first gain stage is set as hot as is reasonably possible as that affects tone throughout the chain, and fewer gain stages are often better than more. I’m paraphrasing; he’s written extensively about this and his writing is worth the search. Built the basic idea is pretty clear.

Since you’re using two very different pickups, the splitter cable becomes a better idea - the McIntyre will require the first (piezo) channel with high input impedence (it has something like a 10Mohm impedence) and the SD magnetic can use the second channel, which is used for mics or mags usually, with an input impedence in the 4KOhm range. That’s two entirely separate inputs for different instruments using the different pickups, which can certainly help optimize the sound.

Use the Rane’s EQ to basically dial in a sound you like for each pickup, and be careful cutting mids, as that’s where a lot of the beauty of the sound of an acoustic lies.

The Soundcraft is kind of a blunt instrument - you should be able to set it flat and use it as a second gain stage, really which may not even really be necessary. I’m not entirely certain the Soundcraft is needed unless you’re using it to mix in a vocal mike or are adding effects like reverb or delay from the board’s built-in FX or whatever. The Rane’s output is plenty hot and balanced and if you don’t need more channels or FX, it’s enough on its own.

If your signal is just a single XLR (or even stereo) from the Rane for both pickups’ signals, you probably don’t need the Soundcraft; just go straight from the Rane out(s) to the Hafler. Chances are good that the removal of an unnecessary gain stage will help.

Let us know what you find....

[sdelsolray]

The Rane AP13 output section has (i) balanced XLR mic level outputs and (ii) balanced TRS line level outputs. The level difference between these two different outputs is 40 dB, all other settings in the AP13 being equal. This is because the XLR outputs each have a -40 dB pad in front of them. The TRS outputs do not. If you use the line level outputs (the TRS output jacks) you will not need the Soundcraft mixer at all, in terms of gain staging. You can just connect the AP13 directly to the Hafler. If you use the Rane XLR mic level outputs you will need to use the Soundcraft mixer to get the signal back up to line level before connecting to the Hafler power amp.

On Edit: Since you are only using one W803 speaker, and as previously discussed in another of your threads, you should to set to Halfer to bridged operation. Working backwards from there (and assuming you are connected the AP13 directly to the Hafler), set the AP13 out stereo/mono switch to mono and run your output from the AP13's TRS jack designated as mono to the Hafler bridged (mono) input.

As to gain staging issue, and your comment, "It's possible I also am not sure how the Rane: Trim, Output slider and Level Slider work in conjunction":

a) Trim control: This is the main gain staging control, +6 dB to +60 dB. Read the manual. Use the overload light indicator as recommended.

b) Output slider: This only adjusts the level of the assigned piezo pickup channel to the piezo output jack on the back of the AP13. That output jack is usually used as a send to a monitor. The output slider is NOT in the direct signal path. Put another way, if you're not using the piezo output jack on the back of the AP13, the Output slider does nothing.

c) Level slider: This is a hybrid attenuator and 10 dB gain stage, post insert and post eq, but before the effects loop.

d) Main out level: This is a another hybrid attenuator and 10 dB gain stage, post every circuit except the headphone circuit. There is another overload light here to help with gain overload detection.

The Rane AP13 is capable of generating +86 dB of gain

[M Hayden]

Thanks for the correction - I forgot one xlr and two TRS. I usually just use the XLR....

[funkymonk#9]

Great Everyone, that helps immensely, also Sdelsolray you've cleared most of my confusion.

I have 2 clarifications. I understand that I don't need the soundcraft for gain but until I get a proper reverb unit, it has some options.

With the soundcraft, is it recommended to use the xlr or TSR output of the Rane? I know you and manual state the XLR needs soundcraft to get to a suitable level.
And also, the mono switch you referenced: the manual just says engaging it switches it from mono to stereo. I assume pushing it in makes it mono out.

Otherwise I feel much more confident with the controls, now onto EQ'ing.

[The Kid!]

You want the best signal to noise ratio. Make sure you're just under where it clips. Your mixer should have solo buttons.