To check a buzzing and eliminate the GUITAR, is it ok to short the amp input to eliminate the guitar?
In all types of classes, SS, tube, Class D, and chip?
In all types of classes, SS, tube, Class D, and chip?
There are even 1/4" jacks intended for the instrument side of a cable that shorts when not plugged in (like the Neutric Silent series)
OK, but should not mater as the input should have a resistor, from 10K to 100K input to ground, a DC blocking cap and RF filter. SOP is not always based in science.
If SOP means "safe operating practice" it needs to be based in science, otherways it's not safe. And shorting the input is different from 10k or 100k to ground.
Yes it is, but in any half-decent amp it will not make any difference. Input shorting plugs are another mythology from someone who has never looked at a schematic or does not understand electronics. "Seems logical" and reality are not always the same. But as said, it won't hurt anything. Made a lot of money for snake oil salesman back in the day.
SOP is Standard Operating Procedure in English. You well could have a different translation in German.
SOP is Standard Operating Procedure in English. You well could have a different translation in German.
In circuits where the input referred noise is dominated by the bias resistor, or where input lead dress is less than optimal, shorting the input WILL reduce the amount of noise. Such would also be quieter driven from a k-follower or op amp as opposed to a 12AX7 with a 100k plate load. Sometimes it is noticeable.
Others: note we are talking about GUITAR.
And apparently unexpected noise (probably not the customary 34k).
The standard on-guitar volume knob shorts the guitar's output when on minimum.
Any stage amp which objects to this simple connection deserves to die.
Pissing all around the bush won't change that.
And apparently unexpected noise (probably not the customary 34k).
The standard on-guitar volume knob shorts the guitar's output when on minimum.
Any stage amp which objects to this simple connection deserves to die.
Pissing all around the bush won't change that.
Most guitar amps have input jacks that short the signal path to ground when no plug is inserted.
Where I come from SOP means standard operating procedure.
Amp type, as in SS, tube, Class D, and your others, refers to the OUTPUT to drive a speaker. It has nothing to do with the input.
Pardon me??? A shorting guitar plug is one that shorts across the cord when not plugged into a guitar. It thus simply prevents the free end of the cord touching something and sending a loud noise through the amp. Not for safety or anything so lofty, we just don't want to hear BRAAAAAAAH when we quick change guitars between songs. Nothing mythical about it. All those 10k-100k resistors, blocking caps, and what-not won't prevent an unterminated cord from making noises when touched at the tip.
Where I come from SOP means standard operating procedure.
Amp type, as in SS, tube, Class D, and your others, refers to the OUTPUT to drive a speaker. It has nothing to do with the input.
Pardon me??? A shorting guitar plug is one that shorts across the cord when not plugged into a guitar. It thus simply prevents the free end of the cord touching something and sending a loud noise through the amp. Not for safety or anything so lofty, we just don't want to hear BRAAAAAAAH when we quick change guitars between songs. Nothing mythical about it. All those 10k-100k resistors, blocking caps, and what-not won't prevent an unterminated cord from making noises when touched at the tip.
...da long as it is not happening frequently during the amp operating that I understand. The No Noise 1/4" jacks I know what they are, and that is a good point.
Thanks for the info.
Thanks for the info.
Too late now; but if you see your typo within a few (10?) minutes, you can click "Edit" under your mis-post and finish your thought.
Short straight answer is YES.
Plus all that Enzo said.
99.99% of guitar amps have a shorting jack at the input, so plain unplugging any cable will do it.
That said, sometimes a worn/dirty/broken input jack fails to short, or even worse, stepping on or yanking a guitar cable or amp falling on its face with a plug inserted (all common situations in the Brutal guitar amp world) cracks/breaks PCB tracks leading to jack, sometimes a loose nut cuses it to turn around and jacking internal wiring, all end in an amp "Hey Juan!!!! My amp buzzes horribly even with no guitar plugged" or worse:"buzzes loudly even with a shorted plug in".
PS: minimum acceptable Guitar Pre input impedance is 220k; 470k or 1M even better.
So 1M would be a safe recommendation. Unless it is just a guitar player trying to figure out the problem.
He took his new 100W KATANA back for a noise and thought his guitar caused it, and was worried it would do it again. I said I don't think it would unless it was doing it intermittently while the amp was on, but then you would know. The guitar is an LCR circuit anyway, just wasn't 100% sure about the short.
Thanks