Jcm800 sc20h hiss

[william vogel]

Thanks for the suggestion, just feels a bit odd to already tinker with a brand new amp.. I would expect it to just do it's work

It’s actually doing exactly what it was designed to do. It’s amplifying a low voltage signal from the guitar to a high voltage signal. The guitar signal is amplified enough in the early stages to surpass the level of the voltage rail and becomes clipped/compressed and it’s amplitude no longer rises but the noise voltage is low enough compared to the root guitar signal that it’s able to be amplified and it’s amplitude continues to rise and get more audible amongst the restrained amplitude of the guitar signal. A noise gate simply clips away this low level noise voltage and removes the initial low level signal. It mutes away the very small portion of the signal around the 0 volt line of the input voltage and unfortunately it’s not transparent but will make the amplifier noise floor much lower.

 

[Maxbrothman]

Here's a link to a youtu upload of it

I wish my hiss was as quiet as that sometimes, especially with all those pedals.

You need to test direct to amp first and bypass your pedal rig completely.

Then go back to the pedalboard and sort things out there.

 

[Chris-in-LA]

There seems to be a slight hiss on the video but when you turned everything on, the 60 cycle hum drowned it out. That pop/boom noise seems to be coming from your pedal board. The only problem I really heard was that screaming at the beginning of the video.

 

[daanromein]

I

There seems to be a slight hiss on the video but when you turned everything on, the 60 cycle hum drowned it out. That pop/boom noise seems to be coming from your pedal board. The only problem I really heard was that screaming at the beginning of the vi

There seems to be a slight hiss on the video but when you turned everything on, the 60 cycle hum drowned it out. That pop/boom noise seems to be coming from your pedal board. The only problem I really heard was that screaming at the beginning of the video.

Indeed, the scream is another issue in itself! With 4cm there is way less hiss, but that boom sound is odd. Someone mentioned I should just leave the loop in my multi effect on so the amp doesn't make that sound

 

[Chris-in-LA]

Indeed, the scream is another issue in itself! With 4cm there is way less hiss, but that boom sound is odd. Someone mentioned I should just leave the loop in my multi effect on so the amp doesn't make that sound

Maybe, I don’t mess with loops or boards that much. But, your hiss seemed pretty normal. I just turn my guitar down between songs at rehearsal if the hiss or hum is bothersome.

 

[daanromein]

Maybe, I don’t mess with loops or boards that much. But, your hiss seemed pretty normal. I just turn my guitar down between songs at rehearsal if the hiss or hum is bothersome.

I'll post a video of the hiss later on, when I plug the guitar directly in the amp, way more loud

 

[Hackingthestrings]

Similar hiss problems with my SC20H, cant wait to hear the solution.

 

[ACHIEVEIT]

Mine hisses quite a bit more than my SV20H, but so does my 2203X compared to my 1959SLP so I dismissed it as normal (albeit annoying). Already tried exchanging the whole tube set between SC20H and SV20H - no difference so I attributed it to the circuit. Curious to read the experience of other users.

 

[marshallmellowed]

The level of "hiss", or noise as I call it, in that video is normal. This is one reason I have to have a loop in all my amps, as the loop is the "optimal" location for a noise gate. Put a decent noise gate (Decimator...) in the loop and forget about it. That said, that pop when switching would annoy the hell out of me, which sounds like a time based effect location issue. Reverb, delay... FX should also be in the loop, after the noise gate..

 

[daanromein]

Similar hiss problems with my SC20H, cant wait to hear the solution.

The best solution I found is to use the 4 cable method with my multi effect. Then there is no more hiss

 

[saxon68]

Thanks for the suggestion, just feels a bit odd to already tinker with a brand new amp.. I would expect it to just do it's work

It does. You have no noise when there’s nothing plugged in.

Noise going in gets amplified.