bass effect circuit help

[garethfriend]

I've been wanting to try modifying a few circuits for guitar effects recently to work with bass and build some pedals. A recurring thing that I am wanting to do with a lot of them is to have the low end of the signal bypass the effect-creating bit of the circuit and be blended in at the output. How do I go about doing this? from what I have read depending on the effect there can be phase issues. Anyone got any experience doing this? what should I be putting in before and after the effect part of the circuit?

Cheers

[LukeFRC]

some kinda of buffer, split the signal, one loop into effects and the other into a low pass filter (or even a good old passive tone control) and then another buffer.
alternatively you can play with the input and output caps on the guitar effects to let more bass through.

[garethfriend]

see my understanding was that playing with the input and output caps would change the amount of bass being filtered out, this would work fine if I wanted to send the bass frequencies through the effect rather than round it. The buffer idea sounds like where my thoughts were going but reading up on this was where I hit the conversations on phasing issues (albeit in an only vaugley related application hence the question). If anyone has actually done this for bass it would be good to hear if you encountered this problem or if it is only theoretical.

[paul_5]

You can alter the input cap, but you run the risk of introducing a big 'thump' when you turn the pedal on.

[bremen]

I'd start by splitting the signal thus:

en.m.wikipedia.org/wiki/Linkwitz–Riley_filter

then applying the effect to the hpf path. the outputs of the effect and the lpf could then be summed (you may or may not need to invert the phase of one path depending on the particular effect) or, better, bi-amped.

For component-level crossover designs, check Rod Elliot's excellent site.

sound.westhost.com/project09.htm

Whether you get the effect to work the way you want or not, active crossover and bi-amping can get great results. I use a 800Hz crossover and feed the lows to a 15" and the highs to a 6".

Edited May 27, 2012 by bremen

[Bigwan]

There's a blend circuit online that does exactly what you're after:
http://moosapotamus.net/paralooper.html

[garethfriend]

winner! cheers guys, some things to have a play with there I think.

[Pollinator95]

[quote name='Bigwan' timestamp='1338103713' post='1669522']
There's a blend circuit online that does exactly what you're after:
[url="http://moosapotamus.net/paralooper.html"]http://moosapotamus....paralooper.html[/url]
[/quote]

Yup, I can confirm that it works.