Blackstar Artisan 100 circuit PPIMV and FX Loop Mods

[henter2015]

Hi Folks,

I came across a Blackstar Artisan 100 for a good price and had to buy it, I think essentially is a SPL based circuit, Im planning to install a Metroamp FX loop and a PPIMV.

The loop shoudnt be an issue but Im starting to wonder if the PPIMV would be as easy as it should, from the videos of the amp seem sthat the ERA switch could be making some changes on the Phase inverter circuit, I cant find the schematic anywhere for this amp only a gut shot:

https://www.questmusicstore.com/wp-c...inside-big.jpg

Anyone familiar with this amp that can shed some light for me please?

Cheers,

Jero

[nickb]

Look at it - it's choc full of 10%, probably carbon comp resistors! eew!


I have a schematic for the Artisan 30 if you don't. It might help you to draw one out from looking at the chassis and then your question could be answered. In the 30, after the PI is a half power switch that does nothing other than kill the drive to one half of the output tubes. If the 100 is the same you could replace the two 220K resistors with a dual 220K log pot for a PPIMV.

[henter2015]

Hi, From what I heard the 30 is more on the AC30'ish style, and the 100 is more of a 59 SPL with the voice control switch...

"
10. Voice
The 4-position Voice control operates as a preamplifier tone control shift, while also
controlling the power amplifier damping and gain. In this way it allows the amplifier
to follow the evolution of 100W guitar amplifier design.
The four modes are described in the table below.
Mode Tone Control Character Power Amplifier Character Description
1 Early ’50s Hi Damping / Lo Gain Bright and clean. The tone is like
American Amp an early American amp
2 Late ’50s Hi Damping / Lo Gain Bright and clean. The tone is
American Amp more full like a later American amp
3 Early ’60s British Medium Damping / More power amp gain so the tone
100 Watt head Medium Gain is more crunchy. The tone is like
an early 100 Watt head
4 Late ’60s British Lo Damping / Power amplifier gain is at a
100 Watt head Higher Gain maximum so the amplifier is really
crunchy. The tone is like a later"

I think this is the part that could change the PI part while changing the position... I guess if there is no schematics there is nothing left than dive into it and follow the cables...

Should following the pin 1 and 6 of the PI tube lead me to the resistor I should replace for the PPIMV?

Reg, the carbon comp resistors, is this a bad thing composition/tolerance wise?, It sounds good to me, only thing is LOUD as hell

[nickb]

The right thing to do is dig in and get the complete picture. Then you stand a much better chance of finding a solution without any nasty surprises. I suspect that feedback network bears the brunt of the switching, but that's just a WAG. Sorry I couldn't be more help.