How to mute a preamp.

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Hi
I just finished building an Alembic f2b clone. It sounds simply awesome. As I'm planning to use it live, I'd like to add some "modern gadgets" to it, like a tuner out, a balanced DI out, and a mute switch.
About the mute switch, I was checking the ampeg svt4 schematics. I saw it uses a FET to ground the input signal when muting is needed.
Is it worth doing it? A simple mechanical switch the ground the input signal won't do the job just the same? There'll be any popping\noise issue?
What is the best way to design a muting? I'm not interessed in simplicity, but in the best results.
Thanks!!!

[R.G.]

About the mute switch, I was checking the ampeg svt4 schematics. I saw it uses a FET to ground the input signal when muting is needed.
Is it worth doing it?

If you want a mute and will use it, yes. Up to you.

A simple mechanical switch the ground the input signal won't do the job just the same?

It will do the same job, but requires audio to run to and from the switch on wires. This may be a problem with the wiring or noise pickup. Maybe not. Depends on your mechanical setup.

There'll be any popping\noise issue?

If you switch a DC level, there will be popping. If you don't, there won't be much of one.

What is the best way to design a muting?

Define "best".

I'm not interessed in simplicity, but in the best results.

That's an expensive way to live.

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Hi RG thank you very much for you answer.
So it's possible to achieve a good result (in terms of absence of noise) with a mechanical switch.
I'm also having a look to the Gallien Krueger 700 rb schematics. I've owned that amp, and the muting was absoutely silent. Well, it's achieved with a mechanical switch that disconnects the signal from the input jack from the amp input and grounds the input of the amp.

If I'll decide to go for the mechanical switch, I'll put it just besides the input jack, to have the shortest possible wires. I should work fine. But in this case I won't be able to  have a "remote control", such as a footswitch.

I think I'll experiment with the FET anyway. Can anybody suggest me a schematic to begin from?

[WaveshapeIllusions]

Fender uses FET switching for quite a bit on their newer amps. A lot of it is pretty clever. Most of them have a few things in common. There is usually a diode in series with the gate and an actual mechanical switch that shifts a DC level. A few of them use CMOS chips for switching.

The Fender site has schematics and layouts of a lot of their amps. All are high-quality PDFs.

Alternatively, look at any Boss/Ibanez schematic. All of their pedals use FET bypass switching. RG's site has a good description of how they work.

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thanks, it helps a lot ! I'll check RG's site as well as fender's.

[bluebunny]

If it's of any help, the mute switch on Albert Kreuzer's bass preamp is a simple mechanical switch, grounding the gate of one of the FETs.