Simple y-box schematic needed

[Pavezer]

Hi all!

I'm in a need of simple y-box schematic.
Just pure simple Y-box to drive two amplifiers with one guitar.

That's y-box without any extra hassle. No A/B -option or anything. No switches or anything.

Does it have to be active? I've heard that passive circuits do have a big problem with grounding hum. Is that true? Any experiences?
I would prefer passive box which eliminates the hum, but I'm also keen on simle-enough-active y-box if that's necessary. It should be driven with a battery, not adapter.

Just something simple. I'm not really professional with these, but i can handle basic stuff. That means the simplier the better.

Thank you fellow citizens!

Lale, Finland

[smoguzbenjamin]

You'll want to buffer it for impedance reasons and also to prevent losing signal when driving two amps. Use a buffer with two outputs and you should be OK. It's what I did for my 4-in-2-out mixer and it works fine.

[Pavezer]

You'll want to buffer it for impedance reasons and also to prevent losing signal when driving two amps. Use a buffer with two outputs and you should be OK. It's what I did for my 4-in-2-out mixer and it works fine.

Ok, that's a good idea, thanks.

BUT

It's not a good idea to go and buy a mixer for this purpose.
And not very handy to carry it among the other gear during the gigs. ;)

.:: Lale ::.

[smoguzbenjamin]

Well what you do is just remove the three other inputs and you have a 1-in-2-out splitter. That *is* what you need, right?

All you do is :

Code Select Expand

IN--->BUFFER---->OUT 1
            \--->OUT 2

That should work to feed two amps. But I'm not sure about ground loops. I use this in my bedroom, so I don't know if it'll behave or even be safe with different ground potentials in some venues... I think there's a ABY box schematic at www.geofex.com using two transformers, so all you do is hard-wire it for two outputs.

[Pavezer]

Thanks for the link!

Oh, i wasn't wise enough trying to check those A/B/Y boxes.
It should be quite easy drop extra sections out.

In this one specific schematic says that it deals greatly with ground hum under 7V. Can anyone tell what kind of ground differencies can two very different all tube guitar amplifer give. Does it go easily over that? Or does it not?

One friend told me that Y-splitter should work well with some mouser or so to eliminate the ground hum. But he couldn't help me that much further. Anyone?

I just noticed that "great" Y-boxes may cost around 130$.
Well, i'm tight on money and trying to achieve the best and the cheapest option...

.:: Lale ::.

[Peter Snowberg]

Your bigest problem is going to be ground loops so I would point you toward the same transformer design at GEO.

The difference between ground voltages will be much smaller if the amps are plugged into the same outlet. That will be your best bet to reduce the hum if you don't use an isolated (transformer style) splitter. I have seen some VERY high voltages between what should have been two grounds. Neil Young's sound guy has written about seeing 150 volts between "grounds". I would use the transformer design for sure.

You will find more info at the Jensen web site
http://www.jensen-transformers.com/
http://www.jensen-transformers.com/as/as013.pdf
http://www.jensen-transformers.com/as/as014.pdf
http://www.jensen-transformers.com/apps_sc.html

Good luck!

-Peter