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Not So Subtle Sag
Hi all you FireBottle lovers!

FireBottle... who came up with that name?

A long time ago I built a Sustainor Preamp.
Like I said so many times: this preamp rocks!

I tried new tubes in it, and they were doing a "new tube" thing.

They gave a sag that was *not* subtle!
The harder I hit the strings, the slower the sound came up.

It was fantastic!
After a while the effect was gone though.

As far as I have seen, the SUS kit works time based, there are a few resistors that set the time.
Can it do this kind of sag?

I have an EHX "Attack Decay", that one works by peaks.
When it detects a peak the preset attack and decay times are applied, so that is only based on preset times.

Fun Fact:
This thing can do something I have not seen anywhere else.
If you apply "poly mode" each note that you play gets its own attack and decay, even if you play multiple notes and let them ring!
I have no idea how they did this.
You would have to sample each note seperately as they are played and then play back a sample with the correct envelope.

But how can you extract the different notes?

Nice riddle to think about, but no solution available!

Hi Guys

Regarding the preamp and new tube "sag": My first impression is that there is a marginal grid-stop value that needs to be made higher. new tubes have a bit more gain, noise, and brightness than ones that are broken-in. That gain difference might be exposing the marginal grid-stop.

You might be able to set up SUS-2 to do this but it would take some tweaking and it might have to be wrapped around two stages, for example the input cascade.

Regarding your effects unit: Spectral compression has been around for a long time. The simplest way is to split the forward path into separate frequency ranges, then give each its own side-chain for control.

have fun
Hello Kevin!

It was magic, and it came and went like magic does.
It lasted about an hour.

A SUS-2 around two stages, that is worth experimenting!

Mesa used the Mike Soldano-stage (the one with the 50k in it) as a first stage in their DC3 and DC-5 amps, that gives some sort of sag too.

About the effect:
Hey, that is a nice angle to look at it!

Thanks for all the info!

(04-15-2021, 08:24 AM)Strelok Wrote: A long time ago I built a Sustainor Preamp.
Like I said so many times: this preamp rocks!


Hi Strelok.  Did you build this preamp from the schematics in TUT6?  I'm interested in incorporating the sustainor preamp into my gutted Traynor YRM-1 head.



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