Treble loss with bypass?

[lbw]

Hi,

I've searched all the FAQs and the forum so I hope this newbie question is still appropriate.

I am building a pedal that has a pre-amp in it. I want to have two outputs on the pedal - one for the dry signal and one for the wet signal. I built my pedal and wired everything up but noticed significant treble loss on the dry signal. I've now taken everything out of the pedal to isolate the cause - all I have is an input stereo jack, an output mono jack, a jumper wire connecting the two and the enclosure used for ground (no ground wire connecting the two jacks). Pretty simple. Unfortunately, I still get the same treble loss.

I guess I must be missing something obvious here! Is this simply a case of the loss I would get with a 20ft lead (one 10ft lead on each end of the box when testing compared to one single 10ft lead) or is it a case of some sort of impedence mismatch with the box which actually requires more components for this circuit to be practical?

Any suggestions would be appreciated.

Thanks.

[blanik]

did you tried with a buffer before your pedal? maybe the "dry" channel lost some highs through the wire and the other channel is buffered through your effect? try it with any boss pedal before your effect, the boss will buffer your whole signal and maybe it'll come out the same in both channels?...

R.

[rockgardenlove]

You're gonna want a very high impedance on the wet input side too.  Otherwise the impedance will be significantly lower than it would be otherwise and the pickups will be loaded.  A buffer in front of the whole thing works too, as blanik said.

[lbw]

I haven't tried a buffer as don't have one to try with! Don't have any other pedals either (other than a GT-6 but that is not a valid test!). I thought I would be able to have a total pure clean signal path for the dry signal. This seems to be how most true-bypass pedals are wired?

I am still not sure why my piece of 5cm wire has such a big R - jwC behavior.. Anyone?

[Ronsonic]

I haven't tried a buffer as don't have one to try with! Don't have any other pedals either (other than a GT-6 but that is not a valid test!). I thought I would be able to have a total pure clean signal path for the dry signal. This seems to be how most true-bypass pedals are wired?

I am still not sure why my piece of 5cm wire has such a big R - jwC behavior.. Anyone?

It isn't the 5CM of wire. The dry signal is connected to the input of your booster, which depending on the design could be pulling it down. There is also the capacitance of your cord to and from the gadget. Depending on the quality of cable this could range anywhere from barely audible to substantial. One of the reasons most amps have a treble knob.

Ron

[blanik]

This seems to be how most true-bypass pedals are wired?

your true bypass wiring is probably correct, but it's a known fact that if all your pedals are true bypass you'll end up with some loss from the cable running from your guitar to your effects and to the amp... it's always better to have a buffered device at the begining of your pedal chain (and maybe one at the end...) a tuner (boss, beringher or korg) in front of the pedal chain is quite popular...

R.

[lbw]

It isn't the 5CM of wire. The dry signal is connected to the input of your booster, which depending on the design could be pulling it down. There is also the capacitance of your cord to and from the gadget. Depending on the quality of cable this could range anywhere from barely audible to substantial. One of the reasons most amps have a treble knob.

Except that it is because as I said in the earlier post, for debugging purposes, there is nothing in the box other than two jacks and one piece of wire.

Any suggestions for an input buffer schematic?

Thanks.

[lbw]

Found this, looks pretty good:

http://www.muzique.com/lab/buffers.htm

[blanik]

Except that it is because as I said in the earlier post, for debugging purposes, there is nothing in the box other than two jacks and one piece of wire.

the thing that sucking the tone is not in your effect box it's the cable going from your guitar to your effect and from your effect to your amp...

R