OT: Asistance with EQ Settings

[mr_es335]

Good day,

I have a query with potential remunerative prospects...

1. I require assistance with the configuration of EQ setting for a Nylon-Strung guitar [Link] using a KNA NG-1 pick system [Link]
2. I am employing SAC, using an RME HDSP9632 via ADAT [Link], an ART TubeOpt8 [Link] and a PRO48 DI [Link]
3. I have the the stock SAC chancel strip EQ, the native effects, EQ and the SoundSpot Paradox EQ [Link] [Manual]

Any assistance with at least a starting configuration would be appreciated!

We can discuss fees as well.

Thanks!

PS: I have a similar pickup system for a Steel-Strung guitar and have been able to obtain satisfactory results on my own...but NOT SO with the Nylon-Strung!

[cgrafx]

Hi Dell,

You've done a good job of describing the audio chain options, but haven't said what issue your having.

Feedback, tone, etc? Can you give a specific description of what your having an issue with.

Everything you need to do with EQ you should be able to do directly in SAC.

[mr_es335]

cgrafx,

What I would refer to as the "typical 'qwakie' sound of a piezo pickup".

When I appear to obtain a satisfactory output, there is no volume left.

I do remember someone stating "Cut rather than boost"...but this does not appear to be working here.

Also, I must state emphatically, that I would prefer not having to learn about EQ...but would prefer to have someone tell me what I need to do...even though I do understand that asking such a question may appear to be rather idiotic! I do hope that this makes sense?

PS: I have been able to obtain rather satisfactory results using TH-U and a 7 bank EQ [Link].

• As can be seen, I would also be employing the use of a reverb - either the Valhalla vRoom [Link], vPlate [Link] or vVerb [Link] offering...

[cgrafx]

There are DI's specifically designed to work with Piezo pickups. Radial makes one. (https://www.radialeng.com/product/pz-di).

You may find that the current DI your using is simply not optimized for your particular Guitar/Pickup combination.

The variable impedance control on the PZ-DI will affect the tone you get from the Piezo pickup which could help you get a more pleasing starting point. However you can still do the following procedure with the DI you have.

You might also try plugging the guitar directly into the guitar input on the Tube Opto.

As for gain, the Tube Opto only has 60db of gain which is not huge so keep in mind there is +20db of additional gain available at the top of the SAC input channel. Don't be afraid to use it.

The next issue is going to be specific to the guitar. It is after all an acoustic box with very specific resonant frequencies. The tone you get from the pickup is going to be affected by the location of the pickup on the guitar. Since you can't move the pickup because its fix-mounted at the bridge, your going to have to deal with whatever resonant frequencies are inherently boosted by the guitar body at that location.

If you wanted a direct way to see/measure those resonant frequencies you could mount a speaker on the guitar body, pump some white noise through it and look at the waveform you get back through the pickup.

That option is probably more complicated though, so the fastest way to do this manually is with controlled feedback.

Put a levelizer on the output of your system. Configure it as a brick-wall limiter so you can control how loud the system will get.

Turn up the gain on the channel until you start to get feedback and back off a tiny amount so you're just under the feedback threshold.

Turn on the channel EQ. Select any band, they are all adjustable across the entire frequency range. Set the Q/bandwidth to its narrowest setting. set the gain to Max, and then slowly sweep the frequency while you strum the guitar until you find the 1st resonant peak of the guitar. It will stand out like a sore thumb as you sweep past it.

Once you find the offending peak, set the Q to around 1 octave (or maybe a little less) and adjust the gain to -6 or so, to even out the resonance.

There will likely be 2-3 primary peaks so you will have to repeat this process using a 2nd/3rd band on the EQ. (just start your sweep from above where the previous peak was found).

This whole process can be done pretty quickly and should get rid of the "Honk" your talking about.

[John Ludlow]

(oops - Philip is back - do what he tells you)

This is obviously Philips bailiwick. But until he comes back, here are my thoughts:

I'm presuming that the SAC channel meter indicates that there is very little input signal in spite of the TubeOpto8 channel gain and output being at 12 o'clock. If so, you need to boost the signal before it gets to SAC, as follows:

Is the pad button on either the Pro48 or the TubeOpto8 (interesting box - what do you think of it?) channel pressed in? Un-press it.

If that doesn't work - leave them un-pressed, and try reversing the output level switch on the TubeOpto8 (it's on the back on the left side).

If that still doesn't work, try increasing the channel attenuator on the SAC channel until its channel meter indicates a good input level. It is the second from the top control on the SAC channel.

If that still doesn't work, try increasing the gain and output knobs on the TubeOpto8 channel - but you shouldn't have to do that.

If these still don't work - wait for Philip.

[mr_es335]

Philip and John,

Thanks to the both of you for your assistance! Much appreciated!

I was hoping for a more simplistic approach...which I know is "darn near impossible"...but I was hopeful.

So, I will contact my local guy here for assistance.

PS: The PZ-DI is $330.00 up here...so that one is out!

Thanks, again!

[TomyN]

Try to get a DI with an input impedace as high as possible. Any powered DI will improve the result.
The radial - stagebug SB-4 piezo could improve it further, but the most impressive result is gained by using an powered DI instead of an unpowered one or an default line input.
Some input impeance values
- Default line in: 47k ohms
- unpowered Di: approx 50k ohms
- powered Di: approx 500k ohms
- SB-4: approx 5.000k ohms

Tomy

[TomyN]

Try to get a DI with an input impedace as high as possible. Any powered DI will improve the result.
The radial - stagebug SB-4 piezo could improve it further, but the most impressive result is gained by using an powered DI instead of an unpowered one or an default line input.
Some input impeance values
- Default line in: 47k ohms
- unpowered Di: approx 50k ohms
- powered Di: approx 500k ohms
- SB-4: approx 5.000k ohms
And remember to keep the cable between guitar an DI as short as possible and to keep all possible sources for interference at distance.

Tomy

[cgrafx]

Philip and John,

Thanks to the both of you for your assistance! Much appreciated!

I was hoping for a more simplistic approach...which I know is "darn near impossible"...but I was hopeful.

So, I will contact my local guy here for assistance.

PS: The PZ-DI is $330.00 up here...so that one is out!

Thanks, again!

Actually the EQ approach is simple. It probably sounds more complicated than it is. The whole procedure can easily be done in under 10 minutes. You only have to do the EQ tuning once.

[TomyN]

'We'll fix it in the mix' will not always work, especial in live audio.