SSS Step filters - Here's what I think

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martin manning
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SSS Step filters - Here's what I think

Post by martin manning »

The different versions of the step filters in SSS schematics published here don't seem to make functional sense. Attached is a version (or a correction?) that has a more reasonable and graduated response on the treble side. The key difference is the 0.003 cap going to ground is tied to the treble switch pole, which eliminates excessive treble that results when it is isolated.
Bombacaototal
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Re: SSS Step filters - Here's what I think

Post by Bombacaototal »

Hi Martin, just one question on the filter: What is the function of the 100K to ground. Is it impacting only the treble cut POLE or does it control the gain of the entire filter circuit by leaking signal to ground? What I am interested in understanding is what woud happen for example if one uses higher resistors like 200K or even 300K as ground or lower like 50k
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martin manning
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Re: SSS Step filters - Here's what I think

Post by martin manning »

Increasing that resistor will increase the bass.
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Re: SSS Step filters - Here's what I think

Post by Bombacaototal »

martin manning wrote: Mon Apr 24, 2017 6:54 am Increasing that resistor will increase the bass.
Thanks Martin. In my case I have it wired as Treble and Bass cut (so the other way around compared to your design). This would then mean that changing the resistor would decrease bass, or it does not really matter?

For some reason I thought it would impact more the high filter than the low
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martin manning
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Re: SSS Step filters - Here's what I think

Post by martin manning »

Some tweaking of resistor and cap values to even out the steps and make the response more symmetrical.
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dcribbs1412
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Re: SSS Step filters - Here's what I think

Post by dcribbs1412 »

Thanks Martin
Appreciate your time and work

D
Bombacaototal
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Re: SSS Step filters - Here's what I think

Post by Bombacaototal »

Thanks Martin! Great work. Just wondering if anyone tested this on a built and how did it compare to the previous?
fred.violleau
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Re: SSS Step filters - Here's what I think

Post by fred.violleau »

Hi Martin, is this filter corresponding to the one used on the dumbleland special?

I have found this video on YT and it sound awesome. The filtering seems to really expand the sonic capabilities.

https://youtu.be/zthE05CGFvY

Any schematics of such an amp on ampgarage?

Thanks.



Fred, learning everyday!

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martin manning
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Re: SSS Step filters - Here's what I think

Post by martin manning »

Nice demo of the step filters. Notice the full CCW setting of the High filter changes the sound dramatically, killing all the highs. In the circuit above I've tried to eliminate that and even out the effect of the steps. Here's a start on the Dumbleland http://ampgarage.com/forum/viewtopic.php?f=4&t=8043 , but I don't think a complete schematic or layout has been done here. Member dreric is working on a SSS with this revised filter circuit, and an established builder of SSS-type amps has confirmed to me that the relocation of the 0.003u cap to the treble switch pole sounds good.
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Re: SSS Step filters - Here's what I think

Post by dorrisant »

Insert "fist-bump" emoji here. :D
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martin manning
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Re: SSS Step filters - Here's what I think

Post by martin manning »

dorrisant wrote: Sat Jan 13, 2018 3:17 am Insert "fist-bump" emoji here. :D
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Re: SSS Step filters - Here's what I think

Post by Colossal »

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Re: SSS Step filters - Here's what I think

Post by dreric »

Eric
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Re: SSS Step filters - Here's what I think

Post by Colossal »

Sounds killer! Great job, all around! That is a real beast of an amp.
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Re: SSS Step filters - Here's what I think

Post by pompeiisneaks »

Sounds outstanding! Thanks for the demo! :)

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