[LAU] checking passive input frequencies on non Hi-Z connection

Len Ovens len at ovenwerks.net
Sat May 20 21:43:30 UTC 2017

  On 05/18/2017 07:15 PM, Wayne DePrince Jr. wrote:

> however, when i connect my electric guitar (Lace Sensors and Alumitone
> pickups) and electric bass, both passive, to the TRS connections on inputs
> 1 & 2 of the H5 with gain only at 5 of 10, i get a good sound and strong
> signal, seemingly the same as when they are connected to an interface (in
> this case a Zoom U-44) that supports Hi-Z connections.

> now while i do not yet have a good understanding of Lo vs. Hi-Z, i have
> read various posts about it. they seem to indicate that the passive guitar
> signal would lose some frequencies with this kind of connection and thus
> this setup is undesirable.

A Di guitar sound is an effect if it is through a Di box or not. If you 
like the effect, good stuff. (use your ears is always good advice)

Personally, I have found that I like the sound of an electric guitar 
better if there is a speaker somewhere in the chain.  Even for clean 
sound. Amp emulations can be quite good at rebuilding sound to sound like 
an amp, but then I add a speaker to the chain (even with a solid state 
amp) and there is some difference that I like the sound of.

In the same way, there will be a difference in sound from one preamp to 
any other. Either you like the sound or you don't.

However, electric guitars and electric guitar amps were designed together. 
There was no recording or Di, it was all live performance. The guitar does 
not have an impedance that is a number, it may have a DC resistance or 5k 
to to 15k or so, but it also has an inductance and capacitance (and the 
cable changes that too) and the matching amp has it's own input 
resistance, inductance and capacitance as well. The same guitar through 
any two amps will sound different because of this even if they have the 
same dc impedance. The inductance and capacitance will change the 
impedance with frequency. So any guitar/amp compination will already 
provide some filtering before the sound gets to the preamp.

The amp itself further changes the sound from input to output and of 
course the speaker/cabinet is tuned in the same way the body of an 
acoustic guitar is tuned. So the guitar/amp/speaker/cabinet combination 
providss a complete sound. The Di can't give the same sound though some 
modeling comes close.

This why I say, if you like the sound nothing else matters. Guitars and 
basses are different too, a Di is much more common for recording a bass 
than a guitar where high frequencies are in general not wanted, though as 
a bass player myself, I like the sound of at least some high end on a 
fretless as it accents some of the glides.

Piezo pickups are different again. I use them on both acoustic guitar and 
manolin. They sound just bad into my mixer or just about any Di box for 
that matter. 1 Meg is not enough. That is why so many of them have built 
in preamps.

I have used electric guitar plugged direct into a mixer and been happy 
with the result when looking for a "clean" sound. For anything with a bit 
of roughness or more, I prefer an amp.

Len Ovens

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