Amp Input Impedance- Opinions?

KingsXJJ

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I have a Fender TM Super Reverb loaded with CB’s. I am interested in the difference dramatic changes in input impedance have on guitar tone. I’ll include a screenshot of the specs of the different inputs as well as Fender’s brief description. But I’d love to hear your opinion and experiences regarding this on any amp.

Description (A.and F.):

IMG_0511.png


Specs, Input 1 (both channels) 1M Ohm and Input 2 (both channels) 136k Ohms:

IMG_0513.png


Dynamic, tone, effect on pedals, etc. Hit me with knowledge please!
 
As far as pedals are concerned, I have noticed that if you have a few pedals mostly from the same manufacturer (Boss, MXR, EQD, really anyone) it seems that the feel is consistent or "treble loss" in my opinion is negligible.

There must be some scientific reason for this which I am not aware of.
 

I know really nothing about electronics. But found this which may be of some help to you.
Thanks! Check out the AI

Amplifier input impedance affects guitar tone by interacting with the guitar pickup's output impedance and the cable's capacitance, potentially causing tonal changes like dullness, treble loss, or a lack of sustain. Lower input impedances load down pickups, potentially creating a duller sound, while higher impedances can accentuate the effects of cable capacitance, leading to a darker tone. [1, 2, 3, 4]

Elaboration: [2]
* Pickup Output Impedance: Guitar pickups have a certain output impedance, which varies with frequency. At higher frequencies, the impedance increases. [2]
* Amplifier Input Impedance: The amplifier's input impedance acts as a load on the pickup. [1, 3]
* Impedance Matching: When the amplifier's input impedance is too low, it loads the pickup, potentially leading to a reduction in treble response and a lack of sustain. [1, 3]
* Cable Capacitance: Longer cables have higher capacitance, which can interact with the amplifier's input impedance, especially at higher values, to roll off high frequencies and create a darker tone. [4]
* Ideal Input Impedance: A high input impedance, typically around 1 megohm, is generally considered optimal for guitar pickups, as it minimizes loading effects and preserves the pickup's tone. [3, 5]
* Impact on Tone: Mismatched impedances can result in a loss of high frequencies, a less responsive tone to volume and tone controls, and potentially a lack of sustain. [1, 3, 6]

Generative AI is experimental.
[1] https://www.sweetwater.com/insync/the-truth-about-guitar-connections/
[2] https://www.harmonycentral.com/arti...t-impedance-for-guitar-effects-and-amps-r428/
[3] https://www.guitarworld.com/features/how-impedance-affects-your-guitar-tone
[4]
[5] https://craiganderton.org/how-to-check-input-impedance/
[6] https://forum.pedalpcb.com/threads/whats-all-this-impedance-stuff-about.4903/
 
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