SSS/JM Sig amp/Overdrive reverb Hybrid idea

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dbeasley
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Re: SSS/JM Sig amp/Overdrive reverb Hybrid idea

Post by dbeasley »

Guy77 wrote:Sounds like a great idea valveandsounds. However you go about doing it ( and if your interested in retaining the original clean tone) I have discovered that the 4th tube in the JM Sig circuit adds a nice richness to its clean tone. I tried removing that and did not like the clean tone as much.

Cheers

Guy
Are you referring to the mixer tube for the wet/dry? That is more or less retained here I believe?

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Guy77
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Re: SSS/JM Sig amp/Overdrive reverb Hybrid idea

Post by Guy77 »

dbeasley wrote: Fri Feb 23, 2018 11:45 pm
Guy77 wrote:Sounds like a great idea valveandsounds. However you go about doing it ( and if your interested in retaining the original clean tone) I have discovered that the 4th tube in the JM Sig circuit adds a nice richness to its clean tone. I tried removing that and did not like the clean tone as much.

Cheers

Guy
Are you referring to the mixer tube for the wet/dry? That is more or less retained here I believe?

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Yes that is exactly it, the one half of the mixer tube for the clean (without reverb) signal.

Cheers

Guy
Bombacaototal
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Re: SSS/JM Sig amp/Overdrive reverb Hybrid idea

Post by Bombacaototal »

dbeasley wrote: Fri Feb 23, 2018 11:43 pm That idea is somewhat similar to ODSR#13 I believe. It's reverb is pre OD. It's an interesting idea, but I wasn't a huge fan of the pre OD reverb tone.

Martin, I've omitted the .012uF cap leading into the Filter network in lieu of the .02uF coupling cap coming from the clean channel/OD ratio out.

I've redrawn to replace the bypass toggle with a relay. Will make it easier to control should I decide to make the filters exclusive to the clean mode or OD.

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Not really similar to the #13. That amp first mixes the dry + wet and then overdrives both. In that case the Overdrive signal has reverb on it.

On my design the Overdrive is exactly the same of a ODS with the overdrive signal (dry without reverb and in this case pre-filter) coming right after the tonestack recovery tube.
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martin manning
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Re: SSS/JM Sig amp/Overdrive reverb Hybrid idea

Post by martin manning »

Aaron wrote: Fri Feb 23, 2018 3:10 pmMaybe bias tap it like #0121.
I'm not a fan of the HT-derived negative voltage and B+ string positive voltage for the CF. The negative voltage comes up slowly and the high positive voltage results in a very high potential from the anode to the bottom of the cathode resistor.
dbeasley wrote: Fri Feb 23, 2018 11:43 pmI've omitted the .012uF cap leading into the Filter network in lieu of the .02uF coupling cap coming from the clean channel/OD ratio out.
Then you'll have 0.02u in front of the filter from the clean and 0.005u in OD. The filter response won't be the same, with reduced bass in OD, or a treble boost, if you prefer. That is similar to what happens in an ODS, though.
dbeasley
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Re: SSS/JM Sig amp/Overdrive reverb Hybrid idea

Post by dbeasley »

Martin,

Good point. I might play around with the OD exit cap value a bit to compensate. Will make a note to do that.

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dorrisant
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Re: SSS/JM Sig amp/Overdrive reverb Hybrid idea

Post by dorrisant »

Just for the reference... I tapped the HT for the bias feed in my SSS/JMS. Maybe it will help.

http://ampgarage.com/forum/viewtopic.ph ... 2&start=15
"Education is what you're left with after you have forgotten what you have learned" - Enzo
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