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Projects => Tech Help - Projects Page => Topic started by: bcalla on August 14, 2013, 01:51:30 AM

Title: Zero Point SDX Slam Question
Post by: bcalla on August 14, 2013, 01:51:30 AM
I've seen this question asked in a couple of build reports, but I don't think it was ever answered:
Is there a way to tone down the effect of the slam switch? 

I'd like it to either oscillate a little less wildly, or get to that wild point a little slower or both.
Title: Re: Zero Point SDX Slam Question
Post by: LaceSensor on August 14, 2013, 09:27:57 AM
+1

mine goes fucking mental immediately.
Title: Re: Zero Point SDX Slam Question
Post by: kothoma on August 14, 2013, 10:44:15 AM
You could increase R41 a bit.
But this would also affect the possible maximum of the feedback knob.
But maybe that's OK with you.

(Another idea would be to use a resistor in series with the slam switch.
But the right value would depend on the setting of the feedback pot.)

Signal going from right to left:
Title: Re: Zero Point SDX Slam Question
Post by: kothoma on August 14, 2013, 11:08:52 AM
Almost forgot, of course you have read the following in the build doc:

Quote
Note that the Slam mod will behave differently depending where the Path switch is set. When the Path switch is set to the right, the Slam function will be nearly instant. When the Path is set to the left, the Slam will be a bit more gradual.
Title: Re: Zero Point SDX Slam Question
Post by: Matt on August 14, 2013, 11:33:50 AM
I think you could put a resistor in series with the slam switch to tone it down a bit.  But it will affect every mode, so if you use too high of a resistance, it may not oscillate in every mode.
Title: Re: Zero Point SDX Slam Question
Post by: bcalla on August 14, 2013, 02:16:51 PM
I'm away next weekend, so I'll tinker with this by the following weekend & report back what I learn.
Title: Re: Zero Point SDX Slam Question
Post by: bcalla on September 01, 2013, 01:50:46 PM
It took longer for me to get to this than I expected.  Yesterday I decided to try out the in-series suggestion.  I plugged in a bunch of values from 1k to 22k and decided that 18k worked best for me.  It really tames the slam switch, probably way too much for some of you.  But at the lower values, you can get control of it and still retain some of the insanity.
Title: Re: Zero Point SDX Slam Question
Post by: jkokura on September 01, 2013, 05:24:39 PM
Quote from: bcalla on September 01, 2013, 01:50:46 PM
It took longer for me to get to this than I expected.  Yesterday I decided to try out the in-series suggestion.  I plugged in a bunch of values from 1k to 22k and decided that 18k worked best for me.  It really tames the slam switch, probably way too much for some of you.  But at the lower values, you can get control of it and still retain some of the insanity.

I'm thinking I'm gonna install a 22 or 25K trimmer in series on a bit of perf on mine. I like the path switch set to the right, so I need something to tame that slam switch down a bit.

I also have to tweak the repeats values somewhat as well, as almost all modes goes into oscillation way to early.

Jacob
Title: Re: Zero Point SDX Slam Question
Post by: midwayfair on September 01, 2013, 05:43:19 PM
This might help:

Values referenced are in the Multiplex but they have analogies in the Zero Point.

QuoteI realized that I needed some resistance between pin 2 and ground for it to work, otherwise I was just grounding lug 3 [...]. So it was simply a matter of connecting to the far side of R21. This put 2K resistance between lug 2 and ground and voila, oscillation at all feedback pot settings. Whew! One weird thing about this, though: There's some extra filtering that never happens when oscillating via the switch. So the repeats from the switch sound different than the ones from the feedback pot.

http://www.madbeanpedals.com/forum/index.php?topic=7720.msg66656#msg66656
and more or less repeated in my ZP:
http://www.madbeanpedals.com/forum/index.php?topic=9314.msg81500#msg81500
Title: Re: Zero Point SDX Slam Question
Post by: madbean on September 01, 2013, 08:47:58 PM
I hope to show a little drop in circuit for more control over the Slam switch soon. I have a few things I've tinkered around with. It would be something small enough to build on perf (maybe three or four components).
Title: Re: Zero Point SDX Slam Question
Post by: LaceSensor on September 28, 2013, 08:29:10 PM
I added a 2K2 in series with a 20k resistor and can get a suitable level of slammage regardless of other settings

YMMV