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Active Pickups and Buffer circuits

Posted: 22 Jun 2014, 19:09
by Hosebass57
Hi

I am in the process of building Seam M B Blender Image
and heard that when using Active Bass Pickups a buffer circuit is not necessary.

Can any one shed some light on this and help me with a circuit I can use with Active pickups?

Any insight would be appreciated

Hosebass

Re: Active Pickups and Buffer circuits

Posted: 22 Jun 2014, 20:22
by Nocentelli
Hosebass57 wrote:help me with a circuit I can use with Active pickups?
It should work fine.

The advice that with an active guitar, you don't *need* a buffer applies if someone was thinking about building a separate buffer to go at the start of a long cable and pedal chain to avoid treble loss from cable capacitance etc: An active guitar does this without the need for an extra standalone buffer. If you had any buffered bypass pedal early in the chain, it would have almost the same effect, but with a tiny loss in the cable from guitar->pedal 1.

However, buffers are often included within effects circuits to help "separate" different sections and help reduce unwanted interactivity. A very simple example might be a basic mixer with two separate buffered inputs, so that rolling the output volume pot down on instrument A doesn't silence the whole combined output. The buffers on the B.Blender prevent the pedals in the loop affecting the mixed-in, dry buffered guitar signal and allows a fairly low value blend pot to tightly mix the two signals with minimal "bleed-through" at extremes of the pot travel. I think. I wouldn't remove the buffers on that design.

Also, an "extra" buffer won't usually cause any problems, the exceptions to this that i have come across are usually when non-buffered, direct interaction with the volume pot is necessary e.g volume clean-up on a fuzzface type pedal.