AUDIO KITCHEN Fake Plastic Trees, Руководство пользователя

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What is the Fake Plastic Trees?
Honestly, I can't remember why the Fake Plastic Trees (FPT) project
started. Certainly, the idea of mimicking an EL84 output using a
transformer-coupled JFET got the cogs turning. At any rate, sometime
in 2018 I began to breadboard, and the circuit looked a little bit like
The Big Trees (TBT) with JFETs: I thought I was pretty close.
I was wrong.
Thus, I jumped down the rabbit hole of A/B-ing the circuit with TBT.
In the end, each stage of TBT was analysed and modelled very closely
with the EL84 grid-clipping (honourable mention here, for SPICE-
ninja Dr Damon McCartney’s help on this) also gaining its own stage.
This was crucial to sculpting just the right clipping profile and
compressive 'feel' to the circuit. It meant having almost 40V headroom
on the power supply and weeks of adjusting the time-constant or 'knee'
of the clipping circuit.
Another element which I had assumed would be simple was the output
transformer. This took months and months of trying different
laminations (we ended up with Mumetal) and winding patterns until
we got close. Again, A/B-ing transformers finally brough a Eureka
moment, only to find we couldn't get the laminations in any quantity.
Insert a few more months of wrangling here.
Throughout the development process, I have had TBT and various
prototypes on an A/B switcher in order better honestly to compare and
appraise how close to a genuine valve pedal 'feel' I had got.
Honestly, it’s as good as I can make it, in this moment.
And I think it's pretty good.
I hope you enjoy it too.
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