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

Ralf Mardorf ralf.mardorf at alice-dsl.net
Sun May 21 15:11:43 UTC 2017

On Sun, 21 May 2017 15:05:57 +0200 (CEST), Tim Goetze wrote:
>>Usually all direct inputs, if made for guitar or not, don't provide
>>the full mids and bass provided by a guitar amp and guitar speaker.  
>I'm not sure what "full mids" are supposed to be; in any case a
>passive guitar pickup connected to a low-Z input is a low-pass filter
>with reduced cutoff frequency and resonance.  It loses treble and what
>I would call "bite" or "sheen" or "character" if I wore my audiophile
>hat today.

It should be for "powerful middle frequencies and powerful bass
frequencies". In my more than 30 years recording electric guitars by a
mixing console, it more likely becomes an issue that high frequencies
sound too harsh. This doesn't mean that there might be no loss of high
frequencies, just that it does sound not "powerful" when recording a
guitar by line inputs or microphone inputs and even not when using
special guitar inputs, while the high frequencies aren't the real issue.
A guitar amp and 12" speaker for guitars bias the sound as well and
doesn't provide the neutral high frequencies. Usually, if you like the
guitar sound without "power" (punch), then just noise and/or the level
are an issue, not the frequency response. If noise and/or the level
should be an issue, than a DI box might help, but the same is provided
when connecting a stomp box between guitar and mixing console, resp.
audio interface, but often noise and/or level aren't really an issue. If
you really want to get closer to the sound of an amp with a 12" speaker,
only using a good guitar pre-amp does the job (even if you additionally
should use an amp and/or speaker simulation). Just using a special
guitar input or a DI box doesn't solve the underlying issue, that mixer
inputs and audio interface inputs can't compare to the bias caused by
an amp and a 12" speaker. A parametric EQ helps a lot, but can't do all
of the typically bias caused by a real amp and a real 12" speaker. If
possible, I even use a cheap transistor guitar amp with a guitar
speaker at low volume and a cheap dynamic microphone to record in a
rental flat. This still doesn't sound like a good guitar amp played at
reasonable volume, but still better than any direct recording without
guitar amp and guitar speaker. However, often even this would be too
loud, so recording directly connected to the mixer or audio interface
is required. YMMV!


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